Bucephala albeola) and Hooded Merganser (Lophodytes cucllatus) showing a slight yet significant upward trend during the course of our survey period. Nonmetric multidimensional scaling (NMDS) was used to examine the community structure of wintering waterfowl. The results of the NMDS indicate that there is a spatial structure to the waterfowl communities of Narragansett Bay and this structure has remained relatively stable since the survey began. Our NMDS analysis helps to solidify what is known anecdotally about the bay’s waterfowl ecology, and provides a formalized benchmark for long-term monitoring of Narragansett Bay’s waterfowl communities. Birds, including waterfowl, are preferred bioindicators and we propose using our multivariate approach to monitor the future health of the bay. While this research focuses on a specific area of New England, these methods can be easily applied to novel areas of concern and provide a straightforward nonparametric approach to community-level monitoring. The methods provide a statistic test to examine potential drivers of community turnover and well-suited visualization tools.In 2004, the Atlantic Ecology Division of the US Environmental Protection Agency’s Office of Research and Development began an annual winter waterfowl survey of Rhode Island’s Narragansett Bay. Herein, we explore the survey data gathered from 2004 to 2011 in order to establish a benchmark understanding of our waterfowl communities and to establish a statistical framework for future environmental monitoring. The abundance and diversity of wintering waterfowl were relatively stable during the initial years of this survey, except in 2010 when there was a large spike in abundance and a reciprocal fall in diversity. There was no significant change in ranked abundance of most waterfowl species, with only Bufflehead ( As modern environmental pressures continue to adversely impact natural habitats, global waterfowl populations are declining at accelerated rates. According to the Millennium Ecosystem Assessment, approximately 12% of all bird species are presently threatened with extinction, and 41% of all waterfowl populations are declining in abundance . NarragaIn 2004, the Atlantic Ecology Division (AED) of the US Environmental Protection Agency’s (EPA’s) Office of Research and Development, in collaboration with state wildlife agencies and local environmental groups, began an annual winter waterfowl survey of Rhode Island’s Narragansett Bay (hence forth referred to as the Bay). Every year in January, local wildlife biologists and environmental scientists conduct a comprehensive survey of the Bay’s waterfowl. The waterfowl survey was implemented in an attempt to fill critical gaps in our ecological knowledge about the Bay’s waterfowl communities. While there have been numerous waterfowl studies conducted in this area , we are To determine the underlying waterfowl community structure, we used a multivariate ordination technique, Nonmetric multidimensional scaling (NMDS) . AdditioBirds, especially waterfowl, are often the logical candidates for monitoring environmental health . Since wIt is nearly impossible to overstate the economic and environmental significance of Narragansett Bay to New England. Narragansett Bay contributes meaningfully to the economy through recreation, tourism, fishing, and shipping  taxonomic group due to the difficulty of distinguishing them.Counting is completed from a stationary point from which the entire area  is scanned with binoculars or a spotting scope. Every bird seen on the water surface or on the adjoining shoreline up to 50 m from the water is counted; when possible sex and age were also noted. Large flocks of greater than 100 birds are estimated by counting in groups of ten or one hundred. Observers take as much time as necessary to accurately count and record all waterfowl observed. Most locations require between 10–20 minutes to survey.We initially explored basic population trends for each waterfowl species. This included average abundance and standard deviations between years. We calculated ranked abundance for non-rare species and fitted regression trends and tested significance for each species. Ranked abundance allowed us to examine the relative dominance or rarity of a species given the current community. Furthermore, we assessed total waterfowl abundance and Shannon diversity index by year.We used nonmetric multidimensional scaling to identify the community level structure of wintering waterfowl in Narragansett Bay . NonmetrNonmetric multidimensional scaling was conducted using survey data collected from 2004 to 2011. A Wisconsin double transform, standardized by species percent abundance and by maximum for each species, was conducted on the species data, and Bray-Curtis distance was used to calculate community distance . Total wetland area was calculated from the US Fish and Wildlife Service (US FWS) National Wetland Inventory (http://www.fws.gov/wetlands). National Oceanic and Atmospheric Administration’s (NOAA) bathymetry data were also downloaded from RIGIS.Location was measured as the latitude and longitude of each site’s centroid. Delineated site boundaries were used to calculate area and site perimeter length . Degradeclimatedataguide.ucar.edu). We used the NAO index to investigate whether winter waterfowl habitat selection was impacted by the relative severity of the winter weather. Wind speed variables were calculated from data downloaded from the NOAA National Climatic Data Center (http://www.ncdc.noaa.gov).The North Atlantic Oscillation (NAO) is a large-scale climate index that measures the atmospheric pressure at sea level between the Icelandic low and Azores high, which captures information about the relative intensity of the winter . A stronEnvironmental dataAncillary variables: The abbreviation definitions can be found inClick here for additional data file.Copyright: © 2015 Kreakie BJ et al.2015Data associated with the article are available under the terms of the Creative Commons Zero "No rights reserved" data waiver (CC0 1.0 Public domain dedication).Winter waterfowl surveySpecies data: The abbreviation definitions can be found inClick here for additional data file.Copyright: © 2015 Kreakie BJ et al.2015Data associated with the article are available under the terms of the Creative Commons Zero "No rights reserved" data waiver (CC0 1.0 Public domain dedication).Bucephala albeola) and Hooded Merganser (Lophodytes cucullatus)  .Our final NMDS fit had four dimensions and a stress value of 0.1449 , and is Histrionicus histrionicus) and Common Eider (Somateria mollissima)) are also positioned in the upper left hand corner of the ordination. Northern sites in the Bay are more shallow and marsh-like (sections 2 and 3), with species indicative of this habitat type (e.g. Atlantic Brant (Branta bernicla) and Canada Goose (Branta canadensis)).Species location in the ordination space can approximate how species sort into habitat types along the spatial gradient in the Bay . The uppAfter the removal of correlated variables, ten ancillary variables were fit to the NMDS results . Only laMost sections’ locations in the ordination space did not change drastically between years; they remained in the same relative location of the ordination . The relOur community level analysis allowed us to establish the expected spatial and temporal structure of the Bay’s winter waterfowl communities which can be used to monitor future environmental changes. Spatially, the NMDS analysis formalized several aspects of the Bay’s waterfowl community that were previously understood only anecdotally, and provided a clear depiction of the community spatial structure across the Bay. NMDS as a monitoring tool in conjunction with the baseline conditions identified in this study could be particularly useful in identifying any future changes in waterfowl community structure in this region and change in the Bay’s overall health.Anas platyrhynchos) and American Black Duck (Anas rubripes) use salt-marsh sites at high tide for cover, protection from predators, and feeding, and as sites for roosting at low tide (Cygnus olor) also utilize these sites as they presumably provide ready access to submerged aquatic vegetation on which these species feed (In the upper portions of the Bay (sections 2 and 3), waterfowl habitat is characterized by shallow, salt-marsh dominated coves and sheltered coves and shorelines with ample freshwater inputs. These sites mapped predominantly on the right-side of the NMDS . Dabblinow tide . Severalow tide . Canada Mergus serrator), Common Goldeneye , Scoter species (Melanitta spp.), and Common Eider use this region of the Bay. These species have larger body sizes that enable them to dive in deeper water to take advantage of prey not found in shallow water areas , and of benthic prey such as crabs that migrate to deeper water during winter  or longer-term (weekly or monthly) movements of individuals among sites, or into and out of our study area. Because of this, our ability to detect change in community composition may require data collection over an extended time period. Yet despite these shortcomings, the ease of data collection and robustness of the NMDS method make it a viable long-term monitoring option.In this study we proposed an approach to analyzing long-term waterfowl monitoring data in order to establish baseline conditions against which future trends in community composition and habitat utilization can be compared. This approach provides a quantitative yet visual means to represent baseline community structure and observed patterns of waterfowl distribution, and provides an easily interpreted series of templates against which future observations or patterns of change can be evaluated. Our approach was developed for waterfowl Narragansett Bay, but can be applied to other estuaries and potentially other species, although environmental factors in the model may need to be modified to reflect those relevant to the species investigated. Overall, our approach will help facilitate the use of waterfowl populations, as well as other relevant species, to monitor the environmental health of a large bay.The data referenced by this article are under copyright with the following copyright statement: Copyright: © 2015 Kreakie BJ et al.Data associated with the article are available under the terms of the Creative Commons Zero "No rights reserved" data waiver (CC0 1.0 Public domain dedication).10.5256/f1000research.6080.d42953 . The work seems adequately conducted and is based on a sound dataset that extends along 8 years. I find therefore the work worthy to be indexed. However, I have some concerns about how the work is presented. Overall, it has a too local focus and should be put in a wider context, with clear aims. I hope the following comments, by sections, will help authors to improve the current version.Abstract This section is particularly too local it should give a wider view of the work and its potential contribution beyond the study area. The authors propose a methodological approach that could be extended to other areas, to solve similar questions . The last paragraph of the discussion is written under this philosophy, and part of it could be used here. Of course it’s also important to depict the results, but they need to be better contextualized.Another issue to address is the excess of repetitions (the same problem is applicable to other sections of the manuscript). For instance, Narragansett Bay is quoted eight times in the abstract alone, and the analytical tool "nonmetric multidimensional scaling" is written in full three times (worth introducing here the acronym NMDS).IntroductionAgain I find the text too local. Only the first two sentences of paragraph 1, plus paragraph 4 attempt to put the study in a wider context. I suggest to join (and slightly extend) these wider issues at the beginning, as well as introduce afterwards the proposed methodological approach, and leave the local considerations for the end of the introduction . The text in the current last paragraph related to the economic and environmental significance of Narrangansett Bay could be better suited (and slightly extended) in the discussion. On the other hand, some of the detailed information of the Bay could be moved to the Methods (study site/study method).Waterfowl respond to these stressors at the local up to the regional scale and their responses can be apparent nearly immediately and continue after substantial time lags (4th paragraph).As a last minor comment, it’d be appropriate to provide a reference for the statement thatMethodsStudy site Remove the first sentence from this section . Also consider, if necessary, to move some of the information provided in the introduction here, avoiding repetitions.Survey methodOverall, try to be consistent with the verb forms. Most of this section is written in present tense, but some sentences use the past simple tense.nd paragraph of this section, quote grebes along with ducks, geese and swans . Also in this paragraph, I suggest rewriting the last sentence, to start saying that in most cases birds were identified to species level. For instance: “All birds were identified to the species level, except Lesser and Greater Scaups, that were simple categorized into a single Scaup (Aythya spp.) taxonomic group due to the difficulty of distinguishing them.”In the 2Data analysisJust as a comment, I find that there are too many pre-selected ancillary variables, particularly NAO-related variables. I understand that this has a minor effect, however, as most of them were removed from the final model. On this regard, it’d be worth explaining why a threshold of r = 0.8 was adopted.  In the third paragraph of this section, I’d suggest to change “for in-depth discussion of methods see ” to “”. Also change “All analysis was conducted in R” to “All analyses were conducted in R”ResultsTable 2. Check wording. For instance, at the end of the table caption, change “were not be conducted” to “were not conducted”. I’d suggest changing the last column of the table to %, as this would be more visual for the reader.The last two sentences of the results’ section seem more appropriate for the discussion. This issue, on the other hand (stability of most sections/changes in section 2 over time) deserve some further attention in the discussion.DiscussionAgain I’d slightly change the structure, and try to avoid excessive description. I’d condensate the description of the waterfowl community site by site, trying to avoid references to conservation issues (e.g. implications of highly urbanized areas) here (see below).I feel a bit uneasy with the sentence “In addition to species’ life history strategies, environmental factors can potentially influence waterfowl distribution in estuaries”. I understand that some environmental factors (such as habitat features) are closely related to life history. So maybe change “environmental” to “climatic”/”meteorological”?I’d add a paragraph regarding conservation-related issues, including coastal-development issues (i.e. the higher pressure in the inner Bay), as well as other relevant local considerations, plus references to climate change.Regarding the increase of Hooded Merganser and Bufflehead, why only the latter is discussed? I miss an explanation for the increase of Hooded Merganser too. On the other hand, I miss some more precision regarding the dates of eventsw regarding Bufflehead (e.g. when –roughly- protection measures started to be in place?). And last regarding this issue, I don’t understand why increased protection to buffleheads provides them a competitive advantage in the Bay. They increase in relative numbers, and therefore their rank position changes, but is this an actual advantage in the wintering area?I appreciate the considerations on the limitations of the study, as described in the penultimate paragraph.I have read this submission. I believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above. Thank you so much for taking the time to give us such a thoughtful review. It is clear that your recommendations have greatly improved the text. Below we can included point-by-point responses to your review and have posted a new version based on your comments to F1000Research. Hopefully, this version of the manuscript will be met with your approval. Please let us know if you have any additional concerns or questions. This section is particularly too local it should give a wider view of the work and its potential contribution beyond the study area. The authors propose a methodological approach that could be extended to other areas, to solve similar questions . The last paragraph of the discussion is written under this philosophy, and part of it could be used here. Of course it’s also important to depict the results, but they need to be better contextualized.Response:  We completely agree with this statement.  n fact, early drafts of the manuscript were more focused on developing this method for wide use in environmental monitoring. However, previous reviewers and co-authors felt that we were overreaching and felt it was more interesting to just focus on this particular study area. To compromise, we have added back some text about the broad application of this method.Another issue to address is the excess of repetitions (the same problem is applicable to other sections of the manuscript). For instance, Narragansett Bay is quoted eight times in the abstract alone, and the analytical tool "nonmetric multidimensional scaling" is written in full three times (worth introducing here the acronym NMDS).Response: Thank you for pointing this out. We have rework the abstract (and the remaining text) to remove several of the redundancies and introduced the NMDS acronym to the abstract.Again I find the text too local. Only the first two sentences of paragraph 1, plus paragraph 4 attempt to put the study in a wider context. I suggest to join (and slightly extend) these wider issues at the beginning, as well as introduce afterwards the proposed methodological approach, and leave the local considerations for the end of the introduction . The text in the current last paragraph related to the economic and environmental significance of Narragansett Bay could be better suited (and slightly extended) in the discussion. On the other hand, some of the detailed information of the Bay could be moved to the Methods (study site/study method).Response: We agree that the previous version of manuscript appears to be very local. As noted in the responses to comment #1, we have added and edited to manuscript to broaden the scope and present the application of the methods. Hopefully the reviewer will feel that we accomplished the goal of broaden the manuscripts scope. Yet coauthors and previous reviewer still feel that this research is in essence simple an analysis of bird communities in Narragansett Bay. We feel that their concern of overreaching is valid. Hopefully with these edits, we have found a balance.Waterfowl respond to these stressors at the local up to the regional scale and their responses can be apparent nearly immediately and continue after substantial time lags (4th paragraph).As a last minor comment, it’d be appropriate to provide a reference for the statement that Response: This error has been corrected.Remove the first sentence from this section . Also consider, if necessary, to move some of the information provided in the introduction here, avoiding repetitions.Response: This edited has been included into the recent version. Due to convention, we have decided to leave some of material about the study area in this section.Overall, try to be consistent with the verb forms. Most of this section is written in present tense, but some sentences use the past simple tense.Response: We have reread this section and made edits as needed.  However, this section does require the both the past and present tense.  Since this survey is ongoing and yet the survey design was completed at the beginning of the study, we used verb tense to indicate which decision were made historically and which still are being used.nd paragraph of this section, quote grebes along with ducks, geese and swans . Also in this paragraph, I suggest rewriting the last sentence, to start saying that in most cases birds were identified to species level. For instance: “All birds were identified to the species level, except Lesser and Greater Scaups, that were simple categorized into a single Scaup (Aythya spp.) taxonomic group due to the difficulty of distinguishing them.”In the 2Response: Both of these suggestions have been incorporated. Just as a comment, I find that there are too many pre-selected ancillary variables, particularly NAO-related variables. I understand that this has a minor effect, however, as most of them were removed from the final model. On this regard, it’d be worth explaining why a threshold of r = 0.8 was adopted.Response: We agree that there were a lot of pre-selected ancillary variables.  We knew that we wanted examine the correlations between climatic and other variables and our NMDS structure, but there was not enough literature on the subject to reduce those variablesa priori. Since these variables were computational easy to derived, we decided to error on the side of caution. We also change the wording to thresholding to reflect more accurately how we selected variables.In the third paragraph of this section, I’d suggest to change “for in-depth discussion of methods see ” to “”. Also change “All analysis was conducted in R” to “All analyses were conducted in R”Response: We have corrected both of these errors.Table 2. Check wording. For instance, at the end of the table caption, change “were not be conducted” to “were not conducted”. I’d suggest changing the last column of the table to %, as this would be more visual for the reader.Response: This error has been corrected and proportions have been converted to percentages.The last two sentences of the results’ section seem more appropriate for the discussion. This issue, on the other hand (stability of most sections/changes in section 2 over time) deserve some further attention in the discussion.Response: This comment had been completely incorporated into the text. We have deleted the last two sentences from results. This text has been added the discussion along with additional explanation.Again I’d slightly change the structure, and try to avoid excessive description. I’d condensate the description of the waterfowl community site by site, trying to avoid references to conservation issues (e.g. implications of highly urbanized areas) here (see below).Response: This concern has been addressed through the edits to other comments. I feel a bit uneasy with the sentence “In addition to species’ life history strategies, environmental factors can potentially influence waterfowl distribution in estuaries”. I understand that some environmental factors (such as habitat features) are closely related to life history. So maybe change “environmental” to “climatic”/”meteorological”?Response: We have incorporated this suggestion into the text.I’d add a paragraph regarding conservation-related issues, including coastal-development issues (i.e. the higher pressure in the inner Bay), as well as other relevant local considerations, plus references to climate change.Response:  This concern has been addressed through the additional paragraph in the discussion.Regarding the increase of Hooded Merganser and Bufflehead, why only the latter is discussed? I miss an explanation for the increase of Hooded Merganser too. On the other hand, I miss some more precision regarding the dates of eventsw regarding Bufflehead (e.g. when –roughly- protection measures started to be in place?). And last regarding this issue, I don’t understand why increased protection to buffleheads provides them a competitive advantage in the Bay. They increase in relative numbers, and therefore their rank position changes, but is this an actual advantage in the wintering area?Response:  This paragraph is only intended to speculative about possible reason behind these shifts. We did not explicitly test. It was an interest discovery and we did not want to simply ignore it. We have add some text to this paragraph to it clear that we simply presenting some thoughts about what might be behind this pattern. Clearly more research is needed on this.  I now realize that I should have waited to post the response after the new version was published.  Version 2, which addresses your concerns, is now published.  Sorry for any confusion that this may have caused. General commentset al. 2010 for a related discussion). Many environmental monitoring programs, however, do not have such underlying hypotheses, and are often characterized as being more of the surveillance type (see Nichols and Williams 2006). The main goal is to identify changes – other than due to the stochastic variability of the system. This paper falls in this category – the main purpose is to describe waterfowl communities in a given area, the Narragansett Bay, and identify possible changes . Variables that could drive these changes, and with a relevance for local or regional management, are not included in the analyses – environmental data used refer either to site variables which are unlikely to change  or that rather reflect short-term temporal variation . That in fact identifying the causes of observed changes in waterfowl communities will be hard without having more explicit hypotheses is made clear in some parts of the discussion. How can we know for example if an observed increase in a wintering duck population is due to 1) improved reproductive success on the breeding grounds, 2) lower hunting pressure in the fall, and 3) change in wintering areas . Monitoring environmental systems should, in my opinion, aim at characterizing the state of the system but also the drivers of changes . Doing this without formulating hypotheses (and if possible quantitative models) is difficult. Even if the paper focuses on developing a baseline for environmental monitoring, it also proposes “a statistical framework for future environmental monitoring”. I do not see how the proposed framework will allow for such a quantitative evaluation of hypotheses.Environmental monitoring means different things to different people. It always involves a long-term commitment – that is, a given system is followed up over time, years to decades – but how much this is driven by hypotheses about what drive the changes of the system, and/or about the consequences of these changes, vary. One could use one of the most famous examples of environmental monitoring – the monitoring of CO2 concentrations initiated by Charles David Keeling in 1958 at Hawaii’s Mauna Loa observatory. Keeling was expecting a rise as a consequence of the combustion of fossil fuels, and there were different hypotheses regarding the rate of increase depending on in particular exchange between atmosphere and ocean . Keeling concluded for example in 1960 “At the South Pole the observed rate of increase is nearly that to be expected from the combustion of fossil fuel (1.4 p.p.m.), if no removal from the atmosphere takes place” . This was therefore a strongly hypothesis-driven monitoring – but that did not exclude surprises, in particular the large seasonal variations due to photosynthetic activity. But such surprises often came because there are rather precise expectations about possible changes  or negatively. Taking those years as a baseline might lead to what Pauly (1995) in the context of fisheries call the “syndrome of shifting baselines” (see Clavero 2014 for an example with non-native species). What we see as a baseline is already very different from historical conditions – irrespective of the reference time used to define “historical”. Monitoring requires we determine the state of the system, but calling it a baseline may be rather misleading without at least a comment.A final general comment relates to waterfowl as “logical candidates for monitoring environmental health” (p. 2) because they respond to “a wide array of environmental stressors [...] at the local up to the regional scale”. Clearly, what we monitor should reflect the changes we expect, but they should also allow for disentangling causes of change – for example if managers want to act on these causes. Knowing if for example causes are local or regional will determine where policy decisions should be made. Monitoring system variables, such as waterfowl communities, that are influenced by a large number of drivers at very different scales may make them too “integrative” for management (or scientific) purposes. Of course, it may be that there will be a main driver of change (think of DDT and birds of prey) but that seems to be unlikely in this case. I personally think we should aim at monitoring directly state variables and rely less on indicators, but I understand also the practical  difficulties. But if one relies upon indicators, or surrogates, at least simple conceptual models linking indicators and state variables would help. It would also make transparent assumptions regarding the stability of the links.To conclude, the authors have done a great job organizing and synthesizing a waterfowl survey over nearly 10 years. The nest step – “future environmental monitoring” – should go further and provides us with a conceptual model of expected changes in the waterfowl community as stressors change at different spatial scales, and if one has the necessary information to assess the relative impact of these stressors.Specific comments:NMDS is one among many multivariate methods that can be used for analyzing spatio-temporal community data (see Legendre and Gauthier 2014 for a recent review). These methods do not make assumptions about the distribution of the data (p.2), but they all make assumptions about what is a “good” measure of e.g. community similarity . If one wants to make inference , most analyses rely upon permutation tests which do not rely upon distribution of the data but may be sensitive to dependence among samples. Particularly to identify relationships with environmental variables, alternative approaches to NMDS such as Canonical Correspondence Analysis, would have been interesting to use .p. 4, it is written that the choice of ancillary  variables was “hypothesis driven”. It would have helped to be more explicit about which component of the variation could be explained by these variables, and in what way it was related to the stressors described e.g. p.2. Clearly the first 10 variables (latitude to wetland area) are unlikely to change during the 8 years of the survey, so they would explain the spatial variation only. Wind speed the day of the survey might explain the day to day variation , whereas NAO.fall might reflect weather conditions during migration and early winter.Table 2, p. 5: for counts with skewed distributions, the standard deviation (SD) might be a poor descriptor of the variability . It might be useful to give the range and median in addition to mean and SD.Table 3: what is meant by “results”? Correlations? How are P-values calculated?Bucephalap. 7:p. 8: species’ life history strategies: use traits rather, you do not really investigate strategies here.I have read this submission. I believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above. General CommentsThis study provides an excellent contribution to our knowledge of baseline species diversity and abundance for the waterfowl community in Narragansett Bay, Rhode Island. The authors analyze longitudinal survey data from the Narragansett Bay Winter Waterfowl Survey (NBWWS) in order to detect shifts in the species composition of the water waterfowl community and to explore if environmental drivers might be driving any change. On a regional scale the study covers almost the entire bay, and considering the general paucity of such monitoring programs, this study is important in that it documents baseline knowledge of the species diversity and abundance of the areas waterfowl and seabird species.Specific CommentsIntroduction:F1000Research (I looked these up but failed to find the citation/reference guidelines), but I think a generally accepted rule of thumb is to not list more than three references per citation .  Nevertheless, when excessive references and citations are used it distracts the reader from the written message and disrupts the flow of the paragraph. I understand that you have to cite certain statements, but I would advice the authors to go through their citations and only cite essential sources. Doing so along with moving the information from the second and third paragraphs to the methods would help streamline the introduction.The main purpose of the introduction was to argue the need for baseline monitoring data for waterfowl communities. The authors do achieve this objective in first and fourth paragraphs, leading to the purpose of study in the last sentence of the fifth paragraph of the introduction. However, I did not find all the information in the introduction leading directly to the statement of purpose of the study, with this statement no matching what was stated in the abstract. The second and third paragraphs for example, include information that would be better suited for the methods. Also, while the authors do a great job in explaining why waterfowl are logical candidates for monitoring environmental health, I found the excessive references of the citations in the fourth paragraph a bit distracting. I am not certain of the editorial guidelines ofMethods:A general comment on the survey technique: As written, the survey methodology explains that complete counts are made in each of the areas corresponding to the site locations. It is not clear however, how observers would delineate the off shore boundaries of the survey areas, particularly those facing each other or off shore boundaries in general. How were these distances discerned? I am curious to how the observers gauged the distance from shore so that birds in the survey area from the opposite shoreline were not recounted. Did they use range finders? Adding some text explaining this would benefit the methods.F1000Research website and found that in the data set describing the winter waterfowl survey (10.5256/f1000research.6080.d42954) the column corresponding to buffleheads is missing. Was a different dataset used for this study? If not, why are buffleheads not included in the dataset but in the result of the study?I downloaded the data that is made available with this study via theFirst paragraph: In the fourth sentence the authors refer to “This area”. I would suggest clearing up what 'area' is being referred to. Also, in the fifth sentence the authors state that the southern portion of the bay is deeper. However, they did not mention deeper ‘than what’. Typically the reader expects to see the full comparison. I know these are nit picky grammar and style comments, but clearing these two minor points would make the paragraph read much better.Fourth paragraph: In the first sentence the authors start by saying “Counting is completed” when the rest of the verbs in the paper are in the past tense. I think changing this to ‘counting was completed’ would be better. In the second sentence, the authors explain: “Every bird seen on the water surface or on the adjoining shoreline up to 50 m from the water is counted; when possible sex and age were also noted”. Is this vertically or horizontally from the water? I am assuming that they mean 50 meters from the waters edge or shoreline – or along the coast.  Please state this more clearly. Seventh paragraph: Please explain why the data was transformed and why the Wisconsin double transformation was chosen. Because non-metric multidimensional scaling uses rank orders, it is not clear why the transformation was used. Stating this more clearly in the text would benefit the paper.Eighth paragraph. In the last sentence, I would suggest using ‘>’ instead of ‘greater than’.Results:It is not obvious to the reader why the data presented in figures 1 & 2 show survey data up to 2012, while the ordination only used data up to 2011. Stating this reason more clearly in the methods would benefit the paper.The legend of Table 2 is not clear. Changing the wording could help clear up the message of the legend. For example, the last two sentences state: “*Species making up less than 1% of the community, and considered rare. Trend analysis  were not be conducted on these rare species.” The tense is wrong here, please change analysis to analyses. Also I would suggest saying this a bit clearer using fewer words, with perhaps something like this? “Species with overall species compositions < 1% were considered rare and excluded from trend analysis”. On this note, if I understand correctly, the legend states that trend analyses were not conducted on rare species and then refers to Figure 3. Figure 3 however shows trends in rank abundance of all 23 species listed in Table 2. This is confusing. Clearing this up in the legend or text would benefit the paper.Regarding the non-metric multidimensional scaling (NMDS), why were four dimensions chosen over two or three? Did solutions with fewer dimensions have too large stress value? Was this assessed with a scree plot?  Stating these details would benefit the paper and help the reader understand why four dimensions were the best choice for the NMDS analysis. Furthermore, in Figure 4, where the results of the NMDS are first shown, it is not clear why are king eiders and long-tailed ducks not shown in the plot. I am assuming from table two that this is because these two species have proportions of the total waterfowl community abundance that are close to zero. Using this logic however, barrow’s goldeneyes should also be excluded from the plot—but they are not. As the NMDS analysis is the central component of the study, the authors should either include all 23 species or clearly state why only 20 were used. As is, the results are somewhat confusing and distract the reader from the overall message of the study.The authors use Figure 5 to detect shifts in the waterfowl community structure of Narragansett Bay during the 8-yr period of the study (2004 and 2011). It is confusing why the NMDS plots in Figure 5 are different to those in Figure 4. I might be missing something, but should not the ordination plots in Figure 5 have the same points and axes as in Figure 4? Are these plots showing the other two dimensions of the ordination?  The details of Figure 5 should be made more elaborate explanation in the text. I am assuming the plots in Figure 5 show the average ordination positions for each section-year combination, with these being color coded for each year. Instead of this exercise, I would suggest authors use analysis of similarity (ANOSIM) to tests hypotheses of community change in each of the sections or the entire bay throughout the 8-yr study period.  In this way the authors could obtain an objective measure indicating if there has been community change (or no change) in the waterfowl of Narragansett Bay during the 8-yr study period. Using ANOSIM here would be analogous to using ANOVAs to assess before and after changes at certain breaks in the 8-yr study period.  ANOSIM however, uses the same similarity matrices imputed into NMDS and is philosophically allied with NMDS ordination. The functions need to perform this analysis are included in the R vegan package, which the authors have shown to have an excellent handle on using. Including ANOSIM in the study to objectively assess temporal changes in the beta diversity of the Narragansett Bay waterfowl community would therefore fit in nicely in the study as as it complements NMDS.In the last paragraph of the results the authors state: “it is thought that waterfowl communities in this part of the Bay vary greatly according to the intensity of winter and amount of ice”. This statement should have a citation referring to the reference thinking or hypothesizing this mechanism. Discussion:First paragraph. In the first sentence, I would suggest replacing “expected” for “baseline”. In the third sentence the authors refer to NMDS as a monitoring tool. NMDS is an ordination analysis used to interpret ecological data, and not a monitoring tool. I think this statement could be reworded better saying for example: “Using NMDS to analyzing monitoring data is a valuable approach to assess…”Sixth paragraph: Again, NMDS is not an approach—it is an analytical tool. Using this ordination technique is the approach the authors took to assess the community structure of the Narragansett Bay waterfowl community. Addressing and fixing this accordingly, will benefit the flow of the text.The second objective of the of the study was to explore if environmental drivers that might be driving changes in the species composition of the waterfowl species composition. I think this objective needs to be addressed a bit more in the discussion. It is only touched upon lightly. Furthermore, what do the authors think is the reason why they found strong correlations of the average wind speed for the three days prior to survey, area, mean bathymetry of site and latitude with the ordination, and yet the wintering waterfowl species composition of the bay seemed to remain stable through time.I have read this submission. I believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above. We greatly appreciate your feedback on our manuscript.  Your thorough and thoughtful review has allowed us to significantly improve the manuscript.  Below are point-by-point responses to your comments.  Your concerns will be reflected in version 3 of the manuscript.  Thank you again for all your help.  Please let us know if you have any additional concerns. 1. The main purpose of the introduction was to argue the need for baseline monitoring data for waterfowl communities. The authors do achieve this objective in first and fourth paragraphs, leading to the purpose of study in the last sentence of the fifth paragraph of the introduction. However, I did not find all the information in the introduction leading directly to the statement of purpose of the study, with this statement no matching what was stated in the abstract. The second and third paragraphs for example, include information that would be better suited for the methods. Response: This concern was also expressed by the first reviewer of the manuscript.  For version 2, we added considerable text to the introduction about how this method could have broader application.  In the first version, you are correct in suggesting this text should be moved to the Methods section.  However, the second version expands the statement of purpose.  Hopefully these edits will address your concern. F1000Research (I looked these up but failed to find the citation/reference guidelines), but I think a generally accepted rule of thumb is to not list more than three references per citation .  Nevertheless, when excessive references and citations are used it distracts the reader from the written message and disrupts the flow of the paragraph. I understand that you have to cite certain statements, but I would advice the authors to go through their citations and only cite essential sources. Doing so along with moving the information from the second and third paragraphs to the methods would help streamline the introduction.2. Also, while the authors do a great job in explaining why waterfowl are logical candidates for monitoring environmental health, I found the excessive references of the citations in the fourth paragraph a bit distracting. I am not certain of the editorial guidelines ofResponse: We completely agree that the amount of references were distracting. We have selectively reduced the number of citations in this part.  Specifically, we removed several of the older citations. Most of the material from the older works was more comprehensively covered in the more recent work. 3. As written, the survey methodology explains that complete counts are made in each of the areas corresponding to the site locations. It is not clear however, how observers would delineate the off shore boundaries of the survey areas, particularly those facing each other or off shore boundaries in general. How were these distances discerned? I am curious to how the observers gauged the distance from shore so that birds in the survey area from the opposite shoreline were not recounted. Did they use range finders? Adding some text explaining this would benefit the methods.Response: To clarify this issue, we added text the first paragraph of the Survey Method subsection of the Methods.F1000Research website and found that in the data set describing the winter waterfowl survey (4. I downloaded the data that is made available with this study via the 10.5256/f1000research.6080.d42954) the column corresponding to buffleheads is missing. Was a different dataset used for this study? If not, why are buffleheads not included in the dataset but in the result of the study?Response:  The wrong data set did get uploaded to the F1000Research page.  Thank you for pointing out this mistake. The correct data are now available.5. First paragraph: In the fourth sentence the authors refer to “This area”. I would suggest clearing up what 'area' is being referred to.Response: We have changed to this test to “The land surrounding the northern portion of Narragansett Bay.”6. Also, in the fifth sentence the authors state that the southern portion of the bay isdeeper. However, they did not mention deeper ‘than what’. Typically the reader expects to see the full comparison. I know these are nit picky grammar and style comments, but clearing these two minor points would make the paragraph read much better.Response: We have added ”than the portion near Providence, Rhode Island.”  Also, we completely agree that this paragraph now reads much better.7. In the first sentence the authors start by saying “Counting is completed” when the rest of the verbs in the paper are in the past tense. I think changing this to ‘counting was completed’ would be better.Response: This error has been corrected.8. In the second sentence, the authors explain: “Every bird seen on the water surface or on the adjoining shoreline up to 50 m from the water is counted; when possible sex and age were also noted”. Is this vertically or horizontally from the water? I am assuming that they mean 50 meters from the waters edge or shoreline – or along the coast.  Please state this more clearly. Response: We have incorporated this recommendation into the text.9. Please explain why the data was transformed and why the Wisconsin double transformation was chosen. Because non-metric multidimensional scaling uses rank orders, it is not clear why the transformation was used. Stating this more clearly in the text would benefit the paper.Response: We have added text to clarify why this transformation was performed.10.  In the last sentence, I would suggest using ‘>’ instead of ‘greater than’.Response: This change was added to the text.11. It is not obvious to the reader why the data presented in figures 1 & 2 show survey data up to 2012, while the ordination only used data up to 2011. Stating this reason more clearly in the methods would benefit the paper.Response:  At the time of the analysis, all the environmental variables were not available through 2012.  The waterfowl survey for 2012 was available and had gone through our QA/QC process.  We decided to include another year into the population, since we were specifically looking for significant trends.  We have added clarification to the text about this issue.12. The legend of Table 2 is not clear. Changing the wording could help clear up the message of the legend. For example, the last two sentences state: “*Species making up less than 1% of the community, and considered rare. Trend analysis  were not be conducted on these rare species.” The tense is wrong here, please change analysis to analyses. Also I would suggest saying this a bit clearer using fewer words, with perhaps something like this? “Species with overall species compositions < 1% were considered rare and excluded from trend analysis”. On this note, if I understand correctly, the legend states that trend analyses were not conducted on rare species and then refers to Figure 3. Figure 3 however shows trends in rank abundance of all 23 species listed in Table 2. This is confusing. Clearing this up in the legend or text would benefit the paper.Response:  We apologize for the confusion.  These was a change in approach that obviously did not get corrected in all parts of the final manuscript.  Previous reviewers request that all species be presented in Figure 3 and therefor that figure was edited accordingly.  The manuscript has been corrected to reflect the presented data.13. Regarding the non-metric multidimensional scaling (NMDS), why were four dimensions chosen over two or three? Did solutions with fewer dimensions have too large stress value? Was this assessed with a scree plot?  Stating these details would benefit the paper and help the reader understand why four dimensions were the best choice for the NMDS analysis. Response:  We explained our process for selecting the number of dimensions in the Methods .  In addition, we added text to the Results (second paragraph). 14. Furthermore, in Figure 4, where the results of the NMDS are first shown, it is not clear why are king eiders and long-tailed ducks not shown in the plot. I am assuming from table two that this is because these two species have proportions of the total waterfowl community abundance that are close to zero. Using this logic however, barrow’s goldeneyes should also be excluded from the plot—but they are not. As the NMDS analysis is the central component of the study, the authors should either include all 23 species or clearly state why only 20 were used. As is, the results are somewhat confusing and distract the reader from the overall message of the study.Response: All 23 species were indeed used to construct the plot.  Both long-tailed duck and king eider plot very low on the y-axis.  Since this is a very complicated plot, we decided to zoom in slightly to have a better view of the main cluster.  This also allowed us to make our labels more legible.  However, we failed to explain this in text.  We have added text to the figure capture to explain this decision and to report values for long-tailed duck and king eider.15. The authors use Figure 5 to detect shifts in the waterfowl community structure of Narragansett Bay during the 8-yr period of the study (2004 and 2011). It is confusing why the NMDS plots in Figure 5 are different to those in Figure 4. I might be missing something, but should not the ordination plots in Figure 5 have the same points and axes as in Figure 4? Are these plots showing the other two dimensions of the ordination?  The details of Figure 5 should be made more elaborate explanation in the text.Response:  The subplots in figure 5 are the same plots as in figure 4.  For figure 5 we greyed out the site locations, and added the average section location with a square symbol.  However, as you pointed out, this is not intuitively clear.  We added text in the figure caption to clarify this issue.16. I am assuming the plots in Figure 5 show the average ordination positions for each section-year combination, with these being color coded for each year. Instead of this exercise, I would suggest authors use analysis of similarity (ANOSIM) to tests hypotheses of community change in each of the sections or the entire bay throughout the 8-yr study period.  In this way the authors could obtain an objective measure indicating if there has been community change (or no change) in the waterfowl of Narragansett Bay during the 8-yr study period. Using ANOSIM here would be analogous to using ANOVAs to assess before and after changes at certain breaks in the 8-yr study period.  ANOSIM however, uses the same similarity matrices imputed into NMDS and is philosophically allied with NMDS ordination. The functions need to perform this analysis are included in the R vegan package, which the authors have shown to have an excellent handle on using. Including ANOSIM in the study to objectively assess temporal changes in the beta diversity of the Narragansett Bay waterfowl community would therefore fit in nicely in the study as it complements NMDS.Response: We agree that ANOSIM would tell us if the groups are different and different by year.  In figure 5 we are trying to show how the sections change through the years in context to the of the entire Bay waterfowl community.  Hopefully, the additional text will clarify our intent to the audience.  Additional, we added considerable text to the discussion in version 2 that adds to the interpretation of this figure. 17. In the last paragraph of the results the authors state: “it is thought that waterfowl communities in this part of the Bay vary greatly according to the intensity of winter and amount of ice”. This statement should have a citation referring to the reference thinking or hypothesizing this mechanism. Response: This material was moved to the Discussion in version 2.  We have added a citationto this state.18.  In the first sentence, I would suggest replacing “expected” for “baseline”.Response: This concern was corrected in version 2.19.  In the third sentence the authors refer to NMDS as a monitoring tool. NMDS is an ordination analysis used to interpret ecological data, and not a monitoring tool. I think this statement could be reworded better saying for example: “Using NMDS to analyzing monitoring data is a valuable approach to assess…”Response: In version 2, we added text to clarify how we feel that this method could have broader appeal.  However, we do agree that the NMDS is an ordination analysis.  We have edited the text to address this concern.20.  Again, NMDS is not an approach—it is an analytical tool. Using this ordination technique is the approach the authors took to assess the community structure of the Narragansett Bay waterfowl community. Addressing and fixing this accordingly, will benefit the flow of the text.Response: See above for explanation about how this issue was corrected.21. The second objective of the study was to explore if environmental drivers that might be driving changes in the species composition of the waterfowl species composition. I think this objective needs to be addressed a bit more in the discussion. It is only touched upon lightly.Response:  The first reviewer of the manuscript agreed with your concern.  Therefore we add material to the Discussion in the second version to further explore our interpretation on the environmental drivers.22. Furthermore, what do the authors think is the reason why they found strong correlations of the average wind speed for the three days prior to survey, area, mean bathymetry of site and latitude with the ordination, and yet the wintering waterfowlspecies composition of the bay seemed to remain stable through time.Response: As mentioned above, we did add text to Discussion about these issues.


Covert contraceptive use (CCU) in sub-Saharan Africa is an indication of women’s inability to exercise autonomy in their reproductive choices. The aim of this study was to assess the prevalence and determinants of CCU among a sample of FP clients in a municipality of Ghana.We conducted a mixed method study among women attending a public reproductive health clinic in Sunyani, a city of over 250,000 inhabitants in Ghana. An initial survey inquired into sociodemographic characteristics, use of family planning (FP) methods and partner awareness of contraceptive use. The predictors of CCU were explored using logistic regressions. We used the findings to develop a guide which we applied in-depth interviews and focus group discussions with attendants at the same facility. Qualitative data analysis was conducted using a framework approach.We interviewed 300 women, 48 % of whom were aged between 26–33 years. The injectable was the most widely used method (56 %). The prevalence of CCU was 34 %. In multivariate analysis, single women were more likely to practice CCU than married or co-habiting women . Muslim and traditionalist women were similarly more likely to practice CCU than non-Muslim, non-traditionalist . Women who preferred to have their first or next child in 4 or more years from the time of the interview were more likely to be in CCU than women who intended to have children within 4 years of the interview . Single women saw in covert use a statement of their social autonomy. To succeed in CCU, women wished that clinic attendance cards would not be given to them to keep at home. Though many participants saw in CCU a source of anxiety, they expected health workers to consider it and uphold confidentiality in the provision of services.Covert contraceptive use was high in this municipality and being single was the strongest predictor of the practice. Providers of FP services should reflect on how to adequately address the challenges faced by women who practice CCU. Covert contraceptive use (CCU) is the practice of using a family planning (FP) method without the knowledge of the partner , 2. In cThe practice of CCU has been studied in different sociocultural settings in SSA. The prevalence is found to be high among women in male-dominated, rural societies. Estimates of between 6 % and over 50 % have been reported , 7–9. AmThe desire of women to use contraceptive covertly is said to reflect in their choice of FP methods –21. MethGhana was one of the first countries in SSA to adopt an explicit comprehensive population policy in 1969. Among the key provisions of the policy is the promotion of FP as an important part of the country’s development agenda. Evidence from the Ghana Demographic and Health Survey (GDHS) 2008 indicates that 98 % of all women and 99 % of all men know of at least one method of contraception. The use of modern FP methods has increased more than threefold (from 5 to 17 %) between 1988 and 2008. In the same period, total fertility rate (TFR) dropped from 6.4 to 4.0, putting Ghana among countries with the lowest TFRs in SSA . In spitVery little is known about current practices regarding CCU in Ghana. This is particularly the case of single women as they have been excluded in most previous studies. Very little is known about how the experience of single women compares with that of women in presumably stable relationships. An improved understanding of the practice of CCU is needed to inform the design of interventions that will promote the ability of women to exercise their contraceptive choices with autonomy, and without strain on their relationships. In the case of single women, it is also needed to inform the design of interventions to reduce unwanted pregnancies and unsafe abortions , 30. We A cross-sectional mixed-method study was conducted at the Reproductive Health Clinic (RHC) at the Sunyani Municipal Hospital, in the Brong Ahafo Region of Ghana. This RHC is part of the public health unit of the Sunyani Municipal Health Directorate and offers comprehensive reproductive health services that include counselling and provision of a wide range of FP methods. The RHC serves an urban population of about 250,000 people, 25 % of whom are women of child-bearing age. The majority of women in Sunyani are petty traders, peasant farmers and workers in the formal sector. Over 90 % of women in the municipality earn less than three hundred Cedis a month  .All women who were using at least one modern FP method and attended the RHC between March and April 2012 were targeted to be interviewed with a questionnaire that inquired into sociodemographic characteristics, type and duration of use of the method and male partner awareness of the use of a method. The question to elicit CCU was posed as “Is your partner aware that you are using a modern FP method?” The questionnaire was administered by a trained research assistant who was a non-health worker. To assess the extent to which women were economically-empowered, a question was asked about the proportion of their total household cost that was supported by their income. Respondents were also asked about their willingness to recommend the use of modern family planning methods to their friends, and whether their own use of modern FP methods conflicted with their religious beliefs. The interviews were conducted in the respondent’s preferred language. Although they were conducted within the premises of the RHC, privacy was ensured with the use of a private room within the facility. A target sample size of 300 women was set to afford 95 % confidence level in estimating the prevalence of CCU within a margin of error of 5 %, assuming a covert use prevalence of 26 %.P-value was less than 0.05. Only variables that were statistically significant in the bivariate analysis  and multivariate (adjusted) logistic regression analysis was performed to identify predictors of CCU. At both bivariate and multivariate levels, an association was considered to be significant if the two-tailed The findings of the survey were used to develop a guide for conducting in-depth interviews (IDIs) and focus group discussions (FGDs) to further explore the practice of CCU and contextualize the findings of the survey. The guide explored the concept of autonomy among single women, the influence of religion, birth spacing and spousal communication and how they affect CCU. A research assistant with experience in qualitative data collection conducted the IDIs and FGDs. A purposive sample of 36 clients at the same facility were asked to participate in 8 IDIs and 4 FGDs between January and February 2015. The participants were selected based on the fact that they were clients to the facility. We actively sought to include women who were current users of a modern FP method. However a few (less than 10 %) of the participants in the FGDs were women who were not on any method but were at the clinic to discuss the various options with the FP counsellors. All the participants however needed to willingly volunteer to participate in the IDIs and FGDs. The number of IDIs and FGDs was dictated by resource availability and time limitation. No woman participated in both IDIs and FGDs.Except in the case of IDIs with two women who declined, all IDIs and FGDs were tape-recorded, transcribed and typed into computer. Both women who declined tape-recording were Muslims who feared they could be heard on tape by a third party who might compromise their CCU. They were however agreeable to notes being taken and reported. We used a framework approach to analyse the data. The framework was based on the findings of the survey and the guide we used in the IDIs and FGDs. The objective was to obtain information that will help to contextualize the findings. Emergent themes were also sought and noted. The analysis, including coding were performed by two researchers who worked independently but later compared and reconciled their findings.We interviewed 300 women in the survey. This represented 99 % of the women we approached. The only woman who refused to be interviewed gave no reason for her refusal. About 97 % of the respondents were aged between 18 and 41 years, and nearly half (48 %) were between the ages of 26 and 33 years. The majority (74 %) were either married (58 %) or co-habiting (16 %). About 26 % of women interviewed were single (including divorced or separated). While a fifth (20 %) of women had no children, 42 % had two or more. Of those who were single, divorced or separated, 45 % had at least one child. Only 26 % of respondents had had education beyond high school. About 9 % of them had had no formal education. The majority (75 %) were Christian. Muslims and traditionalists (worshippers of other deities) constituted the remaining 25 %. The majority (76 %) of women lived within the Sunyani metropolis. Only 14 % of women indicated that they made financial contributions that met at least 50 % of their total household costs. The FP methods used by participants included the injectable (56 %), oral contraceptive pill (18 %) implant (12 %) and intrauterine device (8 %). Overall about a third (34 %) of women admitted to CCU. This however varied according to the type of FP method being used Fig. n = 6) was the strongest independent predictor of CCU. Single women were more likely to be in CCU than married or co-habiting women . Table Being single, including being divorced or separated  and the number of children they had  did not significantly predict CCU in multivariate analysis. This was not particularly surprising to participants in the IDIs and FGDs. A few participants opined however that they expected younger women and women who had about four children or more to be more likely to practice CCU. This was linked to the findings regarding singles and disagreement with spouse over the desired target number of children respectively.Among the factors related to FP intentions and practices that were explored, only the desired length of time to a next (or first) pregnancy was found in multivariate analysis to be significantly associated with the likelihood of CCU Table . Women w“The side effect of the injection is minimal compared to the other methods”“Yes, I use the injectable not because I wish to hide it from my husband, but because I want to avoid the risk of forgetting.”“The nurse told me it was the best”“I was told the nurse who could put the IUD was not around. So I opted for what was available”Although the use of the COC was associated with CCU in bivariate analysis, this was not found to be an independent predictor in multivariate analysis. The practice of CCU was not found to be significantly associated with the use of any particular FP method Table . DiscussIt was generally felt however that methods such as the injectable, implant and intrauterine device were easier to use covertly than the oral contraceptive pill.“I am not ok with using contraceptive without the knowledge of the my partner but I do not want my husband to take another wife”Overall, women did not consider CCU to be an ideal practice since, among other reasons it denied them the support of their partners. Such support included reminders of dates of clinic appointments, compassion and understanding when hormonal contraceptives caused disruption to menstrual flow and interfered with sexual pleasure. It also put them at considerable risk of the loss of trust in case the partner found out. Women appeared to be compelled into CCU by the circumstances of their relationships which may it difficult for them to bring up issues about contraceptives use with their partners. Underlying this concern was a fear that they could be suspected of infidelity. The fact that they could not anticipate partner support also constrained women in their choice of methods as they had to choose methods that were least likely to disrupt the pattern of menstrual flow or sexual pleasure. From both personal and non-personal experiences, participants mentioned some of the consequences of unsuccessful CCU to be physical abuse, extramarital affairs, withdrawal of financial support and threats of divorce.In order to achieve covert contraceptive use, women appeared to go to great lengths. A participant recounted how she travels nearly 40 km to come to the RHC just so his husband does not find out that she is visiting a FP clinic. Another women recounts how after each visit to the clinic she passed by her mother’s house to drop her RHC attendance card before proceeding to where she lives with the husband.“They should assist us by keeping the folders in the hospital instead of giving to us to take home”“They should have a high sense of confidentiality, because some of them are staying in our areas and may come into contact with relatives of ours”On what women wanted the attitude of health workers to be towards CCU, there was unanimity about the expectation that FP nurses and counsellors need to appreciate the challenge clients faced in this regard. They felt that nurses and counsellors needed to consider it a duty to support them to achieve their intention of covert use. Some went further to suggest ways through which health workers could assist. It included the clinic making a policy to keep all patients cards at the facility and not giving any materials to clients to send home.This study has used a mixed-methods approach to explore the practice of CCU among women attending a reproductive health clinic in a municipality in Ghana. The CCU prevalence of 34 % found in this population compares with 7 % in urban Zambia , 31 % inFrom the sentiments expressed by women in this study, it appears CCU is not a practice that women readily admit to. It is thus probable that the CCU prevalence of 34 % found in this study may well be an underestimation of the true extent of the practice. In any case, such a high level of CCU cannot be ignored by the health system and needs to be taken into account in the planning of reproductive health services in this and similar health facilities in Ghana. There is the need for more in-depth studies into the practice with the view to developing interventions that will assist women who are uncomfortable with covert use and need assistance to engage their spouses to be supported while women who wish to maintain covert use are assisted to do so. Currently reproductive health services in Ghana maintain no routine records on the extent of covert use. Women distressed by spousal disapproval of contraceptive use have no formal avenue for seeking assistance within the health service. Greater advocacy is needed to bring the issue of CCU to the fore. Interventions need to be developed to respond directly to the challenge that it poses to the right of women to have unfretted access to the full range of options in FP methods, and to be open about it if they wish to do so. The other attributes of the practice of CCU such as the influence of religion and birth spacing intentions are consistent with established knowledge about the adoption of FP methods by women in Ghana , 27, 32.Although CCU has rarely been mentioned in relation to single women, it has been anticipated that the problems associated with communication and reproductive decision-making could still apply , 40. In P-value = 0.0004) [In this study, although women were of the view that using the injectable, IUD and implants better facilitated covert use than the pills, we did not find a significant association between the type of methods women used and whether they used them covertly or otherwise. This finding is in contrast with that of a study in urban Ndola in Zambia where users of the injectable were 4 times likely to be in covert use than users of the OCP  , 41. In  0.0004) , 42, 43.This findings of this study have highlighted the well-reported disconnect in attitude towards contraceptive use between partners , 44. It In this urban sample, we found that mass media was the dominant source of information on FP. We consider this to offer leverage for the FP program in Ghana as it creates the possibility for sending messages that are targeted at overcoming specific challenges to FP access and unfretted use. Promotional messages that are designed on the basis of evidence from research into the practice of CCU need to be developed. They should be targeted at increasing knowledge and countering the many myths and misinformation that persist in Ghana about FP . InterveOur study has a number of important limitations. The sample size was not adequate enough to enable in-depth exploratory analysis of the factors that were found to be independently associated with CCU. The inadequacy in the size of the sample also manifested in the wide confidence intervals around some of the estimates in the multivariate model. It also affected analysis of the data on the effect of the main sources of FP information. Interpretation of views expressed in the FGDs should also take into account the fact that some participants were not on any modern FP method at the time of the study. Another limitation was the lack of data on provider and health system factors that may have affected the type of FP methods women ultimately used. The analysis in this regards would have enhanced by the availability of data on the quality of FP services and the availability of the different types of FP methods. An inadvertent error in pre-categorising the ages of respondents at the time of questionnaire design also limited the amount of information that could be generated in that analysis.Covert contraceptive use is a sign that providers must continue to take into account women’s rights to confidentiality in FP services . The praCCU, covert contraceptive use; FGDs, focus group discussions; IDIs, in-depth interviews; OCP, oral contraceptive pills; SSA, Sub-Saharan Africa; TFR, total fertility rate


During the extraction, a portion of oil remains trapped inside the cells and its release requires the degradation of the walls and cell membranes, especially when the fruits have not reached a maximum maturity which is likely to cause an optimal embrittlement of the parietal structures and cell membrane. This can be done by specific enzymes necessary for the degradation of various cellular barriers. Three different enzyme treatments proteolytic, pectolytic or both are applied on the Moroccan Picholine olives from veraison to maturity of the fruit. The effect of these treatments is evaluated by olive oil diffusion, its phenolic content (PC) and cellular embrittlement determination of olives during ripening. The pectolytic activities lead to a significant increase in both the oil extractability (76 % at veraison and 14 % at maturity) and the PC (up to 50 % of gain compared to the control at veraison and 27 % at maturity). The proteolytic activities applied alone have no significant effect on the extractability and the polyphenols levels of oils. Furthermore, when these proteolytic activities are added in combination with the pectolytic activities, the oil extractability is doubled at veraison and its flowing up to 99 % at maturity that barely 84 % in the control in addition to a richness of polyphenols which can reach 84 % more compared to the control. This increase in polyphenols wealth is probably due to the degradation of cell walls, cellular and vacuolar membranes by enzyme activities releasing PCs that were previously associated with these structures in the drupe. The beneficial effects of olive oil on human health are due to both its high content of monounsaturated fatty acids and antioxidants  and the pericarp (the skin) contain 96–98 % of the olive oil and only 2–4 % is in the endocarp (pit). During extraction, a portion of oil remains trapped inside the cells and release requires the degradation of the walls and cell membranes, especially when the fruits have not reached an optimal fragility. This can be done by specific enzymes necessary for degradation of various cellular barriers. Enzymes present in the fruit of the olive are generally made ineffective during the process of extracting oil or grinding step because of their inhibition by phenolics compounds present in the cells. Furthermore, many studies have been conducted on the effects of exogenous enzymes on the extraction and the characteristics of the olive oil , fruit with small reddish spots (second sample), fruit turning colors and purple fruits (3rd and 4th samples) and completely black fruit (5th sampling).For each sample, three enzymatic treatments are performed on pitted olives: (1) Treatment with a proteolytic enzyme [4 grams/hectoliter (g/hl)] (2) Treatment with a pectolytic enzyme (4 g/hl) (3) Treatment that combines the previous two enzymes (4 g/hl for each enzyme). These enzymes are commercial preparations containing a number of specific activities for the degradation of the membrane proteins and polysaccharides which ensure the rigidity of the cell wall. Pitted olives under the same experimental conditions without the addition of enzyme activities constitute the control.Sample moisture was determined by drying olive fruits in an olive stove at 105 °C according to the UNE Standard Spanish Method Aenor . A 40 g-The extraction of the total oil content is carried out using hexane in a Soxhlet extractor for 4 h from the dryer used for the determination of humidity content material Aenor . After tThe procedure of phenolic compounds extraction from olive fruit is based on the method of Brenes et al. , with soThe assay of total polyphenols is based on the reduction of acid phoshomolybdique of Folin-Ciocalteu agent by polyphenols in alkaline medium  with 0.2 g of Triton X-100 using a Polytron homogenizer. 25 mg Polyvinylpyrrolidone (PVPP) were added and the suspension was centrifuged at 4 °C for 15 min at 13,000 rpm. The supernatant is filtered through glass wool and used as a source of crude enzyme  by the method of Nelson .The pectinestérases enzymes (PE) are assayed by the method of Baron .An analysis of variance was performed for each parameter studied. The multiple comparison test averages Tukey post hoc is used to test for significant differences between treatments (at 5 %). Univariate analysis was used to test for significant differences in treatment, their interaction for a single parameter. All statistical analyzes were performed with IBM. SPSS statistics, version19. The results of each experiment are made of triplets.During ripening olives, fat content increased on a regular basis since veraison until full maturity Table . This inThe quantities of oil extracted undergo a steady increase during ripening Table , reachinMoreover, in the industrial extraction phases, olives do not release all of their oil, much remains locked inside the pomace cells. Table The contents of total polyphenols in oils are quite high during ripening and then decrease during the ripening and this whatever the enzyme used Table . MoreoveAt veraison, the pectins component of the cell walls of olives consist mainly insoluble protopectins. Soluble pectin extracted by water and by sodium oxalate represents a small portion from the whole pectins Table . During Furthermore, Fig. Whatever the enzymatic treatment used, there is still a decline in protopectins content and increased in the contents of soluble pectins during ripening with decrease of the gap between these two types of pectins maturity. This affects the total contents of pectin since protopectins represent almost all pectins at veraison Fig. . In addiPectocellulosics cell walls isolated by ethanol precipitation (MIA) were found to contain significant amounts of polyphenols that may be released during the extraction of oil. The enzymatic hydrolysis of the MIA obtained from olives harvested at full maturity with the proteolytic and pectolytic activities used for the extraction of fat Table  shows thThe ripening of Moroccan Picholine olives variety is accompanied by increased in oil content. These contents do not exceed 15 % at maturity and are quite low compared to the Moroccan varieties that can reach 19, 22 and 23 % respectively of the fresh material for varieties Dahbia, Haouzia and Menara , is directly related to high values of the activity of PE in fruits and low activity in PG. This may promote calcium bridges formation in pectin chains and therefore smaller losses of the total pectin content (Mínguez-Mosquera At the end of ripening, the PG activity peaks and degradation of the pectic material increases but at a lesser level than that detect early ripening since the fruit reaches its full maturity. Heredia et al.  proposedThe application of proteolytic activities does not have any significant role in the degradation of cell walls and this whatever the harvest date. Contrariwise, the application of pectolytic activities on olives allow a very significant degradation of olives tissue structures with a decrease in protopectins levels from veraison to maturity and these levels are lower than those of the control mainly when these pectolytic activities act in combination with the proteolytic activities. Under these conditions, the use of these activities results in a weakening of the parietal cell and membrane structures allowing the release of a larger amount of the cell contents. These observations are also confirmed by the liberation and enrichment of oil with phenolic compounds. In fact, in the absence of any enzymatic activity, the contents of phenolic compounds in oils decrease about 68 % during the maturation, while the contents in olives only decreased by 10–20 % which confirms the hypothesis of the presence of a physical barrier preventing their release. This hypothesis, which states a bond of polyphenols with polysaccharides of the cell walls and the component proteins of vacuolar membranes, is confirmed by the use of pectolytic and proteolytic activities: If the proteolytic activities alone have no influence on the release of phenolic compounds from olives, the pectolytic activities alone and especially in combination with the proteolytic activities allow to enrich the oils with these compounds and this from veraison. The levels of oils enrichment with phenolic compounds by the combination of exogenous proteolytic and pectolytic activities increase during the first stages of ripening when the cell walls of olives are not completely weakened by endogenous activities then these levels decrease towards the end of ripening when the parietal structures are naturally degraded by endogenous activities. Under these conditions, the hypothesis of the presence of a mechanical barrier which opposes the release of phenolic compounds in the oils is verified: we can conclude that the pectolytic activities degrade the parietal structures releasing the polyphenols related to parietal structures but also the polyphenols that are released by the degradation of the component proteins of vacuolar membranes. The use of proteolytic and pectolytic activities on the insoluble material alcohol consisting mainly of pectocellulosic structures of olives cell walls confirms the hypothesis of the presence of polyphenols bound to the cell walls of the fruit, but also to the vacuolar membranes making their release difficult during the extraction of oil. The release of these polyphenols in the medium is made possible by the degradation of the parietal and membrane structures of the cells by enzymatic activities. These results are in agreement with those of Vierhuis et al.  who haveThe role of the proteolytic activities in combination with pectolytic activity was studied on the release of the fat and phenolic compounds during the extraction of olive oil. In this study, we were able to highlight the presence of phenolic compounds linked to difficult releasable parietal structures during oil extraction. Furthermore, we showed that the application of proteolytic activities alone are ineffective on extractability of the cell contents, while their use with the presence of pectolytic activity causes an increase in the diffusion of the fat and it is wealthy on phenolic compounds mainly when olives have not reached sufficient maturity. The action of these activities lies in the fact that firstly the proteolytic activities degrade the component proteins of membrane structures releasing the polyphenols associated with these structures and promotes the diffusion of the oil, on the other hand, the pectolytic activities degrade the parietal structures allowing the passage of the cell contents and releasing the same time the polyphenols associated with cell walls that can enrich the phenolic content of oil.


This modification eliminates inconsistencies in greenhouse gas reporting by recognizing the role of the forest and timber sector in the global carbon cycle. Any additional CO2-effects related to wood usage are not considered by this modification. This results in a downward bias when the contribution of the forest and timber sector to climate change mitigation is assessed. The following article analyses the overall contribution to climate protection made by the forest management and wood utilization through CO2-emissions reduction using an example from the German state of North Rhine-Westphalia. Based on long term study periods . Various alternative scenarios for forest management and wood usage are presented.At the 15In the mid- to long-term  the net climate protection function of scenarios with varying levels of wood usage is higher than in scenarios without any wood usage. This is not observed for all scenarios on short and mid term evaluations.The advantages of wood usage are evident although the simulations resulted in high values for forest storage in the C pools. Even the carbon sink effect due to temporal accumulation of deadwood during the period from 2011 to 2100 is outbalanced by the potential of wood usage effects.2-effects of the forest management requires an assessment of the forest supplemented with an assessment of the effects of wood usage. CO2-emission reductions through both fuel and material substitution as well as CO2 sink in wood products need to be considered.A full assessment of the COAn integrated assessment of the climate protection function based on the analysis of the study’s scenarios provides decision parameters for a strategic approach to climate protection with regard to forest management and wood use at regional and national levels.The short-term evaluation of subsystems can be misleading, rendering long-term evaluations  more effective. This is also consistent with the inherently long-term perspective of forest management decisions and measures. In the philosophy of UN-FCCC the act of increasing a forest’s carbon stock by increasing levels of standing biomass volumes is recognized as an emissions reduction measure. Stored carbon is released through biological decomposition in the forest back into the atmosphere mainly in the form of CO2; only a smaller fraction of the carbon is ultimately stored in the soil.Forests play a significant role in the global carbon cycle. They sequester CO2 emissions occur )The scenarios are based on simple assumptions, for example:The carbon sink capacity of the forest and the annual timber harvest amounts were calculated for each management strategy scenario. Harvested timber amounts were assigned to tree species or wood categories by means of a utilization code. The wood utilization code was regionalized by developing an idealized material-flow model starting with the timber harvest data (based on harvest statistics from 2002–2010) all the way to the final product. The development of the material-flow model was based on national studies on wood usage, e.g., , and wasChanges in the harvested wood products’ carbon stock are calculated by determining the net input of the carbon in the wood products to the overall HWP carbon pool according to , 52.emission reduction through material and fuel substitution is taken into account at the time the substitution occurs. The calculation of the emission reduction of wood used as fuel is recorded as a credit at the time when the wood is  burned. For wood residues from wood product manufacturing this occurs immediately, for old wood this happens at the time of the End of Life of the respective wood product (recycling is considered).The emission reduction through material substitution is defined using the approach presented by Sathre and O'Connor [2 emissions (expressed as C) of competing products is set in ratio to their carbon content. Sathre and O'Connor [2 emissions. Sathre and O'Connor's approach, however, only applies to the comparison of two specific products, therefore the mean value of 2.1 tC/tC calculated by them is not always applicable or suitable, it is rather arbitrary based on the studies they selected in their analysis. For a specific case, where a wood market as a whole  is being analyzed, it is necessary to compare the overall product mix in its whole structure (product types and quantities) as well as the mix of competing products.The O'Connor , wherebyO'Connor  describeMa for material substitution was determined as follows . The prThe 16 product areas were classified taking into account the quantity distribution of wood usage from the material flow analysis by Mantau and Bilitewski  for GermMa = 1,50 tC/tC. This factor is valid for Germany.Based on those four product groups, specific substitution factors and the respective quantitative distribution between those four product groups, a single substitution factor comprising all four product groups was then established/determined to be SFIn this case the substitution factor SFsee also ):InitialMa = 1,50 tC/tC reflects wood usage in Germany; it was not possible to determine a region-specific substitution factor for NRW due to a lack of precise data on material flow and wood usage and a high degree of variability of those data due to the small market size. It can be assumed, though, that the structure of wood usage in North Rhine-Westphalia does not significantly differ from the structure of wood usage nationwide, based on the comparison of several wood-market parameters between NRW and Germany [Ma = 1,50 tC/tC is, therefore, used as an overall average substitution factor for this study; it was applied for the whole study period until 2100.In contrary to the typical wood products from mechanical processing a material substitution factor for paper products is not considered because adequate comparative LCA or EPD are not available.The substitution factor for material substitution of SF Germany . The subThe emission reduction through fuel substitution (substitution factor SFFuel) can be calculated based on the difference between the emissions from a defined energy mix of fossil fuels and the emissions from wood, based on its C-content.2-emissions from burning fossil fuels are based on the specific amount of energy ; the CO2-emissions from burning wood for energy, on the other hand, only take into account the CO2-emissions of fossil fuel used in the earlier parts of the value chain  and burning of the wood (CO2-source) offset each other. The fact that the wood removed from the forests through harvest is assessed as CO2 emission (excluding the wood which transfers to the harvested wood products pool), makes this approach consistent with the international guidelines of the Kyoto-Protocol [The COort; see ). Besideort; see ), using Protocol .Fuel = 0.67 tC/tC for fuel substitution. Rüter [2/m3, which corresponds to roughly 0.65 tC/tC. Calculating the substitution factor based on an energy mix of various forms of fossil fuel which would have been burned instead of wood, also confirms a substitution factor of SFFuel = 0.67 tC/tC [2 emissions which are less or equal to the substitution effect through the emission reduction through the use of wood (cf. [The study uses a substitution factor of SFn. Rüter  derives n. Rüter  determin67 tC/tC . This meood (cf. ). It is For the usage of old and used wood it is assumed that only 80 % of the wood is being used for material or fuel use. The remaining 20 % is left unused, as a result for example of decomposition or of being used in open fires without utilization of its thermal energy. It is further assumed that 20 % of the waste wood volume that is being reused, i.e., the amount of wood available at the “end of life stage” is used only once for the production of particleboard, i.e., products with a medium-term life spans.Fuel = 0.67 tC/tC is assumed at the end of life of the paper products.For pulpwood 85 % energy recovery with a substitution factor of SF


Recently, the master equations for the interaction of two-mode photons with a three-level Λ-type atom are exactly solved for the coherence terms. In this paper the exact absorption spectrum is applied for the presentation of a non-demolition photon counting method, for a few number of coupling photons, and its benefits are discussed. The exact scheme is also applied where the coupling photons are squeezed and the photon counting method is also developed for the measurement of the squeezing parameter of the coupling photons. Electromagnetically induced transparency (EIT) has been theoretically introduced by Kocharovskaya and Khanin  and expeMoreover, profile of the absorption and dispersion spectra are shown to depend on the number of coupling photons so that the number of coupling photons could be measured using the absorption spectrum of the probe photons. This scheme is applied for the presentation of a non-demolition photon counting method. The present method is applied to the squeezed coupling photons. Straightforwardly, it is shown that the exact absorption and dispersion spectra drastically depended on squeezing parameter of the coupling photons. This scheme is also applied for presenting measurement of the squeezing parameter.In “In this section a review on the exact model of a three-level Λ-type atom interacting with two quantized electromagnetic field  interact with a three-level Λ-type atom see Fig. a. The inAssume the system is initially in the ground state entclass1pt{minimaAn ensemble of cold three-level atoms is prepared by an optical pumping initially in the state entclass1pt{minimaThe master Eqs. –7) are  are 7) aThe real and imaginary parts of entclass1pt{minimaIn the next section, a photon counting method based on the exact form of absorption spectrum of the probe field, which is derived from Eq. , is presΛ-type atoms.In this section, a non-demolition photon counting method is presented for measuring the number of coupling photons which are trapped in a quantum cavity and interact with an ensemble of three-level It is worthwhile to estimate the number of probe photons which is required to determine the probe absorption peak. As an example, the cavity field decay rate can be estimated as It is clear in Eqs. –17) and and17) aAlthough Fig. A considerable difference between the plots in Fig. r and Another application of the full-quantum interaction of two-mode photons with three-level Λ-type atoms is in measurement of squeezing parameter of coupling photons. Supposed the trapped coupling photons are squeezed In this case, the interaction Hamiltonian in the interaction picture is given by “” 19\docuEquation  is similentclass1pt{minima in Eqs.  and, aftr, which leads to applying the photon counting method for a squeezing measurement by measuring the DAPs or DDPs.The real and imaginary parts of the probe coherence term  correspor. Furthermore, they are more sensitive to the squeezing parameter for a larger number of photons. Of course, it is important to note that n2 is not the average of coupling photons; but, it can be easily derived by r. Therefore, number of coupling photons and their squeezing parameter can be obtained by measuring DAP and DDP of the absorption and dispersion spectra simultaneously. Some typical values of DAP and DDP are shown in Table By taking a derivative of the imaginary and real part of Eq.  and settmentclass2pt{minimmentclass2pt{minimIn this paper, the master equations of Λ-type three-level atom interacting with two-mode quantized electromagnetic field and its exact coherence term are applied to obtain the squeezed and non-squeezed coupling photons. The following results were obtained: (1) The method was applied for presenting a photon counting and a squeezing measurement method by measuring the absorption spectrum of the probe photons. (2) The difference between the exact and WFA photon counting methods and benefits of the exact method  were demonstrated. This sensitivity increased for the larger number of coupling photons by increasing the squeezing parameter. (3) It was shown that the photon counting method was more sensitive for the smaller number of coupling photons. (4) The present method for the measurement of squeezing was more sensitive for larger values of squeezing parameters. (5) The number of coupling photons and their squeezing parameter can be obtained simultaneously by measuring the DAP and DDP. (6) The photon counting method was non-demolition for the strong coupling photons.