Alexander A. Grabham, Krista van der Linde, Ximena J. Nelson
The photographic identification (photo-ID) of individual animals can be time-consuming and erroneous. Recent efforts to collect photographs of leopard seals (Hydrurga leptonyx) from across their range have necessitated the technological streamlining of photo-ID. We constructed a dataset containing 595 photographs of the head and body of individuals recorded in New Zealand between 2008 and 2022 to test the performance of semiautomated 3 photo-ID programs: HotSpotter, Interactive Individual Identification System's Pattern+ (I3S), and Wild-ID. We classified attributes of photographs (e.g., quality) and individuals (i.e., pelage patterns) to assess their effect on performance. We compared performance using Top20 and Top1 Accuracy, defined as the proportion of test photographs where the highest ranked correct identity was in the top 20 and top 1, respectively, matched reference photographs. HotSpotter outperformed I3S and Wild-ID in both Top20 and Top1 Accuracy of most assessed attributes. Maximizing HotSpotter's performance may be achieved through several methods, including increasing the number and variety of photographs of individuals in the dataset. HotSpotter will likely perform better with photographs without obstructions (e.g., debris from beaches), such as on the pack ice of their primary Antarctic range. We highlight the viability of HotSpotter in assisting the photo-ID of leopard seals, and more broadly, other species with similar markings.
{"title":"Evaluating the performance of semiautomated photographic identification programs for leopard seals","authors":"Alexander A. Grabham, Krista van der Linde, Ximena J. Nelson","doi":"10.1002/wsb.1520","DOIUrl":"https://doi.org/10.1002/wsb.1520","url":null,"abstract":"The photographic identification (photo-ID) of individual animals can be time-consuming and erroneous. Recent efforts to collect photographs of leopard seals (<i>Hydrurga leptonyx</i>) from across their range have necessitated the technological streamlining of photo-ID. We constructed a dataset containing 595 photographs of the head and body of individuals recorded in New Zealand between 2008 and 2022 to test the performance of semiautomated 3 photo-ID programs: HotSpotter, Interactive Individual Identification System's Pattern<sup>+</sup> (I<sup>3</sup>S), and Wild-ID. We classified attributes of photographs (e.g., quality) and individuals (i.e., pelage patterns) to assess their effect on performance. We compared performance using Top20 and Top1 Accuracy, defined as the proportion of test photographs where the highest ranked correct identity was in the top 20 and top 1, respectively, matched reference photographs. HotSpotter outperformed I<sup>3</sup>S and Wild-ID in both Top20 and Top1 Accuracy of most assessed attributes. Maximizing HotSpotter's performance may be achieved through several methods, including increasing the number and variety of photographs of individuals in the dataset. HotSpotter will likely perform better with photographs without obstructions (e.g., debris from beaches), such as on the pack ice of their primary Antarctic range. We highlight the viability of HotSpotter in assisting the photo-ID of leopard seals, and more broadly, other species with similar markings.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"45 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140325258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Janet E. Greenhorn, Carrie Sadowski, Jennifer A. Rodgers, Jeff Bowman
The muskrat (Ondatra zibethicus) is considered a ubiquitous inhabitant of wetlands across Canada and the United States, but recent studies indicate that muskrat populations in many parts of North America have experienced substantial declines over the last 40–60 years. Monitoring of muskrat abundance is therefore an important task for wildlife managers, but traditional methods such as house counts conducted during ground-based surveys can be labor-intensive and time-consuming. Poor conditions or a lack of access may limit how much of a wetland can be surveyed. Aerial imagery has previously been used to census a diverse array of wildlife populations but is not yet a common tool for muskrat surveys. To investigate the accuracy of this alternative survey method, we collected aerial imagery from coastal wetlands along the north shore of Lake Ontario during the winter of 2014 for examination in both 2D orthorectified and 3D stereoscopic formats. We compared muskrat house counts obtained from imagery to counts recorded by ground survey crews in the same wetlands during the same winter. We found no significant difference between mean muskrat house counts obtained by ground survey crews and orthoimagery observers. In contrast, stereoscopic imagery observers overestimated mean house counts compared to ground survey crews, which we interpret was due to an increase in false positives. Our results indicate that orthoimagery is a promising tool for assessing muskrat occupancy, provides comparable broad-scale results to traditional ground survey methods, and may be preferable to wildlife managers for a variety of reasons.
{"title":"The use of orthoimagery and stereoscopic aerial imagery to identify muskrat (Ondatra zibethicus) houses","authors":"Janet E. Greenhorn, Carrie Sadowski, Jennifer A. Rodgers, Jeff Bowman","doi":"10.1002/wsb.1519","DOIUrl":"https://doi.org/10.1002/wsb.1519","url":null,"abstract":"The muskrat (<i>Ondatra zibethicus</i>) is considered a ubiquitous inhabitant of wetlands across Canada and the United States, but recent studies indicate that muskrat populations in many parts of North America have experienced substantial declines over the last 40–60 years. Monitoring of muskrat abundance is therefore an important task for wildlife managers, but traditional methods such as house counts conducted during ground-based surveys can be labor-intensive and time-consuming. Poor conditions or a lack of access may limit how much of a wetland can be surveyed. Aerial imagery has previously been used to census a diverse array of wildlife populations but is not yet a common tool for muskrat surveys. To investigate the accuracy of this alternative survey method, we collected aerial imagery from coastal wetlands along the north shore of Lake Ontario during the winter of 2014 for examination in both 2D orthorectified and 3D stereoscopic formats. We compared muskrat house counts obtained from imagery to counts recorded by ground survey crews in the same wetlands during the same winter. We found no significant difference between mean muskrat house counts obtained by ground survey crews and orthoimagery observers. In contrast, stereoscopic imagery observers overestimated mean house counts compared to ground survey crews, which we interpret was due to an increase in false positives. Our results indicate that orthoimagery is a promising tool for assessing muskrat occupancy, provides comparable broad-scale results to traditional ground survey methods, and may be preferable to wildlife managers for a variety of reasons.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"3 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140324915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nonnative, invasive ants, and especially the red imported fire ant, Solenopsis invicta, are a widespread threat to ground-nesting wildlife. In this paper I describe a method of controlling fire ants using hot water. The hot water approach was applied to reduce fire ant impacts on sea turtles and ground-nesting songbirds and to demonstrate its utility in protection of different ground-nesting species in different habitats. Fire ant controls using hot water provided 90% or greater control, significantly improving survival of both turtle and bird hatchlings, without the use of pesticides. The success of the method and the availability of necessary equipment shows that hot water control of fire ant populations should be considered as a tool for wildlife affected by fire ants and is useful for a wide variety of scenarios where fire ant controls are desirable or necessary. The method does require that 1) wildlife nest locations are known and that 2) nearby fire ant colonies can be found and treated with hot water. The method can be used as a complement to broadcast or bait-station baiting strategies or as a stand-alone method for managing fire ants.
{"title":"Pesticide-free management of invasive ants impacting ground-nesting wildlife populations","authors":"Joshua R. King","doi":"10.1002/wsb.1516","DOIUrl":"https://doi.org/10.1002/wsb.1516","url":null,"abstract":"Nonnative, invasive ants, and especially the red imported fire ant, <i>Solenopsis invicta</i>, are a widespread threat to ground-nesting wildlife. In this paper I describe a method of controlling fire ants using hot water. The hot water approach was applied to reduce fire ant impacts on sea turtles and ground-nesting songbirds and to demonstrate its utility in protection of different ground-nesting species in different habitats. Fire ant controls using hot water provided 90% or greater control, significantly improving survival of both turtle and bird hatchlings, without the use of pesticides. The success of the method and the availability of necessary equipment shows that hot water control of fire ant populations should be considered as a tool for wildlife affected by fire ants and is useful for a wide variety of scenarios where fire ant controls are desirable or necessary. The method does require that 1) wildlife nest locations are known and that 2) nearby fire ant colonies can be found and treated with hot water. The method can be used as a complement to broadcast or bait-station baiting strategies or as a stand-alone method for managing fire ants.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"101 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140182221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We tested the influence of on-shore avian predators on the at-sea distribution and abundance of marbled murrelets (Brachyramphus marmoratus) during their breeding season in Haida Gwaii, British Columbia, Canada. We conducted a field experiment using deterrent predator decoy kites that mimicked flying bald eagles (Haliaeetus leucocephalus). In the summers of 2018 and 2019, we conducted at-sea surveys of murrelet distributions along inshore and offshore transects with and without kites flying, and tallied real eagles along the shoreline and fish schools encountered. Kites negatively influenced overall murrelet counts (estimate = −1.19, 95% CI = −1.88 to −0.51), but we did not detect inshore to offshore movements within the study site. Our results indicate murrelet movement out of the study area in response to the kites. Overall murrelet counts were also lower when real eagle counts were higher (estimate = −0.22, 95% CI = −0.35 to −0.09). When kites were flying, a higher proportion of the murrelets remaining along inshore transects were found between rather than adjacent to kite locations (estimate = −1.61, 95% CI = −2.67 to −0.54), indicating avoidance of kites. Since avian predator populations have steadily increased in the past 30 years throughout the murrelet's breeding range, these avoidance effects could create a negative bias in long-term shoreline count trends. Our findings highlight the importance of considering non-lethal predator effects on murrelets when conducting at-sea censuses and constructing conservation plans.
我们测试了在加拿大不列颠哥伦比亚省海达瓜伊（Haida Gwaii）的繁殖季节，岸上鸟类捕食者对大理石斑海雀（Brachyramphus marmoratus）海上分布和数量的影响。我们使用模仿飞行的秃鹰（Haliaeetus leucocephalus）的威慑性捕食诱饵风筝进行了一项野外实验。在 2018 年和 2019 年夏季，我们沿着放飞和不放飞风筝的近岸和离岸横断面对小椋鸟的分布进行了海上调查，并统计了沿海岸线的真鹰和遇到的鱼群。风筝会对小红 murrelet 的总体数量产生负面影响（估计值 = -1.19, 95% CI = -1.88 to -0.51），但我们并没有在研究地点内发现小红 murrelet 从近海向远海的移动。我们的结果表明，小红嘴鸻在风筝的影响下离开了研究区域。当真正的老鹰数量较多时，小红 murrelet 的总体数量也较低（估计值 = -0.22，95% CI = -0.35 至 -0.09）。当风筝飞舞时，沿岸横断面上的小红 murrelet 在风筝位置之间而不是相邻位置停留的比例较高（估计值 = -1.61, 95% CI = -2.67 to -0.54），这表明小红 murrelet 会躲避风筝。由于鸟类捕食者的数量在过去 30 年中在整个小红嘴雉的繁殖地稳步增加，这些回避效应可能会对长期海岸线计数趋势造成负面偏差。我们的研究结果突出表明，在进行海上普查和制定保护计划时，考虑捕食者对红嘴琵鹭的非致命性影响非常重要。
{"title":"Considerations for a threatened seabird: The impact of shoreline avian predators on at-sea marbled murrelets","authors":"Sonya A. Pastran, David B. Lank","doi":"10.1002/wsb.1514","DOIUrl":"https://doi.org/10.1002/wsb.1514","url":null,"abstract":"We tested the influence of on-shore avian predators on the at-sea distribution and abundance of marbled murrelets (<i>Brachyramphus marmoratus</i>) during their breeding season in Haida Gwaii, British Columbia, Canada. We conducted a field experiment using deterrent predator decoy kites that mimicked flying bald eagles (<i>Haliaeetus leucocephalus</i>). In the summers of 2018 and 2019, we conducted at-sea surveys of murrelet distributions along inshore and offshore transects with and without kites flying, and tallied real eagles along the shoreline and fish schools encountered. Kites negatively influenced overall murrelet counts (estimate = −1.19, 95% CI = −1.88 to −0.51), but we did not detect inshore to offshore movements within the study site. Our results indicate murrelet movement out of the study area in response to the kites. Overall murrelet counts were also lower when real eagle counts were higher (estimate = −0.22, 95% CI = −0.35 to −0.09). When kites were flying, a higher proportion of the murrelets remaining along inshore transects were found between rather than adjacent to kite locations (estimate = −1.61, 95% CI = −2.67 to −0.54), indicating avoidance of kites. Since avian predator populations have steadily increased in the past 30 years throughout the murrelet's breeding range, these avoidance effects could create a negative bias in long-term shoreline count trends. Our findings highlight the importance of considering non-lethal predator effects on murrelets when conducting at-sea censuses and constructing conservation plans.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140172960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aaron N. Facka, Robert C. Lonsinger, Gary W. Roemer
Reliable estimates of prairie dog (Cynomys spp.) population size and distribution are critical for assessing the status of prairie dogs and for selecting sites to reintroduce black-footed ferrets (Mustela nigripes). The density of active prairie dog burrows has commonly been used as an index of prairie dog abundance. Indices derived from active burrow counts were developed for black-tailed (C. ludovicianus) and white-tailed (C. leucurus) prairie dogs, but their efficacy has not been evaluated for all prairie dog species and studies affirming their validity with robust abundance estimators are few. We indexed or estimated the abundance of Gunnison's prairie dogs (C. gunnisoni) in the Aubrey Valley, Arizona, USA, in 2006 at 2 different time periods using 4 different methods—maximum above ground counts (MAGC), minimum number known alive (MNKA), capture-mark-recapture (CMR), and mark-resight—and compared these estimates to active burrow counts in 2005 and 2006. We found no positive relationship between active burrow counts and any abundance estimators. Mark-resight estimates of abundance were greater than the MNKA and were positively correlated with both the MNKA (r2 = 0.30) and CMR estimates (r2 = 0.49). Both CMR estimates and MAGC were typically below the MNKA and therefore biased low. Our results indicated that more rigorous estimation methods may be necessary to accurately estimate prairie dog abundance and assess habitat quality for ferret conservation.
{"title":"Abundance estimates of Gunnison's prairie dogs compared to the number of active burrows","authors":"Aaron N. Facka, Robert C. Lonsinger, Gary W. Roemer","doi":"10.1002/wsb.1513","DOIUrl":"https://doi.org/10.1002/wsb.1513","url":null,"abstract":"Reliable estimates of prairie dog (<i>Cynomys</i> spp.) population size and distribution are critical for assessing the status of prairie dogs and for selecting sites to reintroduce black-footed ferrets (<i>Mustela nigripes</i>). The density of active prairie dog burrows has commonly been used as an index of prairie dog abundance. Indices derived from active burrow counts were developed for black-tailed (<i>C. ludovicianus</i>) and white-tailed (<i>C. leucurus</i>) prairie dogs, but their efficacy has not been evaluated for all prairie dog species and studies affirming their validity with robust abundance estimators are few. We indexed or estimated the abundance of Gunnison's prairie dogs (<i>C. gunnisoni</i>) in the Aubrey Valley, Arizona, USA, in 2006 at 2 different time periods using 4 different methods—maximum above ground counts (MAGC), minimum number known alive (MNKA), capture-mark-recapture (CMR), and mark-resight—and compared these estimates to active burrow counts in 2005 and 2006. We found no positive relationship between active burrow counts and any abundance estimators. Mark-resight estimates of abundance were greater than the MNKA and were positively correlated with both the MNKA (<i>r</i><sup>2</sup> = 0.30) and CMR estimates (<i>r</i><sup>2</sup> = 0.49). Both CMR estimates and MAGC were typically below the MNKA and therefore biased low. Our results indicated that more rigorous estimation methods may be necessary to accurately estimate prairie dog abundance and assess habitat quality for ferret conservation.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"295 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139978821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nathan B. Alexander, Douglas Knutson, Loren Lynch, Madeleine Spellman, Michael Rivera, Leslie K. Morrow, Maxine Scherz, Thea E. Clarkberg, Lucas T. Allen-Custodio, Kal Fountain, Isaac Klimasmith, Emmett M. Smith, Jaime J. Coon
Science has a history of excluding marginalized groups, including people who are lesbian, gay, bisexual, trans, queer, and other marginalized gender and sexual identities (LGBTQ+), and recent calls urge the wildlife sciences to address disparities. Literature on inclusion in the life sciences generally has focused on personal affirmation and has neglected comprehensive discussion of barriers rooted in historical, structural, and sociocultural context. In our literature review, we construct a narrative highlighting the intersections between historic LGBTQ+ exclusion in society and wildlife science due to current policy trends, pressures of cis-heteronormativity, and survival barriers on LGBTQ+ people in wildlife sciences in the United States. Wildlife scientists must have competency on LGBTQ+ marginalization topics to advance inclusion in our discipline, and this should include comprehension of historic and current legislation and social perceptions. To bolster inclusion efforts, we recommend thoughtful data collection on experiences of LGBTQ+ people within the wildlife sciences. To address root causes of exclusion, institutions and organizations should address disparities in financial support, housing, and physical and mental health resources as part of LGBTQ+ advocacy, in addition to interpersonal efforts.
{"title":"Increasing LGBTQ+ inclusion & competency in wildlife sciences: intersections of sociocultural, structural, and historic barriers to inclusion","authors":"Nathan B. Alexander, Douglas Knutson, Loren Lynch, Madeleine Spellman, Michael Rivera, Leslie K. Morrow, Maxine Scherz, Thea E. Clarkberg, Lucas T. Allen-Custodio, Kal Fountain, Isaac Klimasmith, Emmett M. Smith, Jaime J. Coon","doi":"10.1002/wsb.1511","DOIUrl":"https://doi.org/10.1002/wsb.1511","url":null,"abstract":"Science has a history of excluding marginalized groups, including people who are lesbian, gay, bisexual, trans, queer, and other marginalized gender and sexual identities (LGBTQ+), and recent calls urge the wildlife sciences to address disparities. Literature on inclusion in the life sciences generally has focused on personal affirmation and has neglected comprehensive discussion of barriers rooted in historical, structural, and sociocultural context. In our literature review, we construct a narrative highlighting the intersections between historic LGBTQ+ exclusion in society and wildlife science due to current policy trends, pressures of cis-heteronormativity, and survival barriers on LGBTQ+ people in wildlife sciences in the United States. Wildlife scientists must have competency on LGBTQ+ marginalization topics to advance inclusion in our discipline, and this should include comprehension of historic and current legislation and social perceptions. To bolster inclusion efforts, we recommend thoughtful data collection on experiences of LGBTQ+ people within the wildlife sciences. To address root causes of exclusion, institutions and organizations should address disparities in financial support, housing, and physical and mental health resources as part of LGBTQ+ advocacy, in addition to interpersonal efforts.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"145 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139956549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
John D. Stuhler, Carlos Portillo-Quintero, Jim R. Goetze, Richard D. Stevens
Effective management of rare species requires an understanding of spatial variation in abundance, which is challenging to estimate. We tested the efficacy of high-resolution imagery to detect burrows of the Texas kangaroo rat (TKR; Dipodomys elator) as a means of estimating abundance across its geographic range. Specifically, we estimated burrow counts using an Unmanned Aerial System (UAS) to collect data from very high-resolution Red–Green–Blue (RGB) imagery and estimate digital elevation (2.5-mm pixel resolution) over active and inactive burrows located on mesquite mounds and anthropogenic features (roadsides, fences, etc.). In 2018, we identified 26 burrow locations on a private ranch in Wichita County, Texas, USA, and characterized burrows based on topography and vegetation density. We found that TKR burrows can only be identified with data of <5 cm pixel resolution, thus eliminating the possibility of using high-resolution imagery data currently available for Texas. Alternatively, we propose that the use of National Agriculture Imagery Program (NAIP) imagery at 0.5- and 0.6-m pixel resolution, in combination with resampled digital elevation data, can provide an effective means for identifying potential TKR burrow locations at the county level. We present 3 different approaches at the county and local scale that combine topographic and vegetation fractional cover information using a weighted overlay approach. The modeling approaches have strong predictive capabilities and can be integrated with UAS data for visual confirmation of active and inactive burrows. We concluded that very high-resolution imagery and topographic information at pixel resolutions <5 cm collected by airborne systems can effectively help locate active TKR burrows. However, to remain cost effective, upscaling to the county level will require reducing the sampling area to the most suitable habitat. Modeling approaches, such as those proposed in this study, can help effectively locate these sampling areas.
{"title":"Efficacy of remote sensing technologies for burrow count estimates of a rare kangaroo rat","authors":"John D. Stuhler, Carlos Portillo-Quintero, Jim R. Goetze, Richard D. Stevens","doi":"10.1002/wsb.1510","DOIUrl":"https://doi.org/10.1002/wsb.1510","url":null,"abstract":"Effective management of rare species requires an understanding of spatial variation in abundance, which is challenging to estimate. We tested the efficacy of high-resolution imagery to detect burrows of the Texas kangaroo rat (TKR; <i>Dipodomys elator</i>) as a means of estimating abundance across its geographic range. Specifically, we estimated burrow counts using an Unmanned Aerial System (UAS) to collect data from very high-resolution Red–Green–Blue (RGB) imagery and estimate digital elevation (2.5-mm pixel resolution) over active and inactive burrows located on mesquite mounds and anthropogenic features (roadsides, fences, etc.). In 2018, we identified 26 burrow locations on a private ranch in Wichita County, Texas, USA, and characterized burrows based on topography and vegetation density. We found that TKR burrows can only be identified with data of <5 cm pixel resolution, thus eliminating the possibility of using high-resolution imagery data currently available for Texas. Alternatively, we propose that the use of National Agriculture Imagery Program (NAIP) imagery at 0.5- and 0.6-m pixel resolution, in combination with resampled digital elevation data, can provide an effective means for identifying potential TKR burrow locations at the county level. We present 3 different approaches at the county and local scale that combine topographic and vegetation fractional cover information using a weighted overlay approach. The modeling approaches have strong predictive capabilities and can be integrated with UAS data for visual confirmation of active and inactive burrows. We concluded that very high-resolution imagery and topographic information at pixel resolutions <5 cm collected by airborne systems can effectively help locate active TKR burrows. However, to remain cost effective, upscaling to the county level will require reducing the sampling area to the most suitable habitat. Modeling approaches, such as those proposed in this study, can help effectively locate these sampling areas.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"94 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139761984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrew J. Dinges, Jay A. VonBank, Aaron T. Pearse, David A. Brandt
Midcontinent sandhill cranes (Antigone canadensis) are managed as a single population, but hunting regulations are structured so harvest is targeted towards the more numerous lesser sandhill cranes (A. c. canadensis). However, research indicates that greater sandhill cranes (A. c. tabida) have been disproportionally exposed to harvest at a rate exceeding their proportion within the midcontinent population. In addition, harvest has increased 22% per year in the U.S. Central Flyway states. The midcontinent population appears to be growing in recent years, but variability in annual abundance estimates has increased substantially. With limited resources and harvest management uncertainty increasing, we developed methods for a citizen science, photography-based harvest survey to estimate age and subspecies composition of harvested midcontinent sandhill cranes. To develop survey methods, we collected physical parts from 284 sandhill cranes in North Dakota in 2019 and 2020. We manually measured the culmen and tarsus using calipers, and digitally measured these parts using photographs and computer software. All digitally derived measurements were 2.5% to 5.9% larger than manual measurements; therefore, we developed linear models that adjusted digital measurements, facilitating subspecies prediction using an existing morphometric-based technique. In 2021, we requested an equal number of hunters to participate using 2 data collection methods to test if hunters could reliably take photographs suitable for digital measurement. Collection method 1 involved photographing the head and leg simultaneously, and Collection method 2 involved photographing the head only. Hunters submitted a total of 239 photographs. Only 80 of these photographs were submitted using Collection method 1, and 72% were suitable for digital measurement. Conversely, hunters submitted twice as many photographs using Collection method 2, and 88% of these photographs were deemed suitable. Although obtaining the tarsus measurement slightly improved subspecies predictability, Collection method 2 increased participation and usable data. We believe our results could be used to develop an operational survey of age and subspecies composition of midcontinent sandhill cranes, wherein a sample of crane hunters throughout the midcontinent population range would be asked to electronically submit a photograph of the head of each bird they harvest. A time series of age and subspecies composition of this population would provide managers with valuable information and improve harvest management at minimal additional cost and burden, compared to a traditional parts collection survey administered by mail.
{"title":"Developing a photography-based harvest survey to estimate age and subspecies composition of midcontinent sandhill cranes","authors":"Andrew J. Dinges, Jay A. VonBank, Aaron T. Pearse, David A. Brandt","doi":"10.1002/wsb.1512","DOIUrl":"https://doi.org/10.1002/wsb.1512","url":null,"abstract":"Midcontinent sandhill cranes (<i>Antigone canadensis</i>) are managed as a single population, but hunting regulations are structured so harvest is targeted towards the more numerous lesser sandhill cranes (<i>A. c. canadensis</i>). However, research indicates that greater sandhill cranes (<i>A. c. tabida</i>) have been disproportionally exposed to harvest at a rate exceeding their proportion within the midcontinent population. In addition, harvest has increased 22% per year in the U.S. Central Flyway states. The midcontinent population appears to be growing in recent years, but variability in annual abundance estimates has increased substantially. With limited resources and harvest management uncertainty increasing, we developed methods for a citizen science, photography-based harvest survey to estimate age and subspecies composition of harvested midcontinent sandhill cranes. To develop survey methods, we collected physical parts from 284 sandhill cranes in North Dakota in 2019 and 2020. We manually measured the culmen and tarsus using calipers, and digitally measured these parts using photographs and computer software. All digitally derived measurements were 2.5% to 5.9% larger than manual measurements; therefore, we developed linear models that adjusted digital measurements, facilitating subspecies prediction using an existing morphometric-based technique. In 2021, we requested an equal number of hunters to participate using 2 data collection methods to test if hunters could reliably take photographs suitable for digital measurement. Collection method 1 involved photographing the head and leg simultaneously, and Collection method 2 involved photographing the head only. Hunters submitted a total of 239 photographs. Only 80 of these photographs were submitted using Collection method 1, and 72% were suitable for digital measurement. Conversely, hunters submitted twice as many photographs using Collection method 2, and 88% of these photographs were deemed suitable. Although obtaining the tarsus measurement slightly improved subspecies predictability, Collection method 2 increased participation and usable data. We believe our results could be used to develop an operational survey of age and subspecies composition of midcontinent sandhill cranes, wherein a sample of crane hunters throughout the midcontinent population range would be asked to electronically submit a photograph of the head of each bird they harvest. A time series of age and subspecies composition of this population would provide managers with valuable information and improve harvest management at minimal additional cost and burden, compared to a traditional parts collection survey administered by mail.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"5 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139761997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mute swans (Cygnus olor) have increased in New Jersey at ~7%/yr since the mid-1980s with the population peaking at 1,890 mute swans by 2005. Wildlife agencies have implemented management programs to reduce mute swan numbers to population objectives; however, evaluation of these programs is lacking. Given the detrimental impacts of mute swans on wetland habitats, we implemented a cull program in 2007 in New Jersey through shooting, mostly during mid-summer, and focused cull efforts on key molting sites. Our primary objective was to measure the impact of culls on mute swan population trends. We also examined population response of mute swans at key molting sites over time after culls began. We conducted 61 field operations at 21 sites and culled 2,038 mute swans over 11 years. We achieved a mean annual statewide cull rate of 0.15 and reduced the 2005 mute swan population 56% by 2017. The statewide mute swan population declined (P = 0.038) at nearly 8%/yr following commencement of culls. Four heavily used molting sites comprised 79% of the mute swans culled and population response varied across the 4 key cull sites. We fit a linear model using a derived annual cull rate and mute swan abundance data to describe the effect of culls on population growth (λ) and determined that a cull rate >0.09 was required to reduce (λ < 1) the mute swan population in New Jersey. Our work should benefit wildlife agencies who are considering implementing mute swan management programs.
{"title":"Culls effective for reducing mute swans in New Jersey","authors":"Theodore C. Nichols, Lisa A. Clark","doi":"10.1002/wsb.1507","DOIUrl":"https://doi.org/10.1002/wsb.1507","url":null,"abstract":"Mute swans (<i>Cygnus olor</i>) have increased in New Jersey at ~7%/yr since the mid-1980s with the population peaking at 1,890 mute swans by 2005. Wildlife agencies have implemented management programs to reduce mute swan numbers to population objectives; however, evaluation of these programs is lacking. Given the detrimental impacts of mute swans on wetland habitats, we implemented a cull program in 2007 in New Jersey through shooting, mostly during mid-summer, and focused cull efforts on key molting sites. Our primary objective was to measure the impact of culls on mute swan population trends. We also examined population response of mute swans at key molting sites over time after culls began. We conducted 61 field operations at 21 sites and culled 2,038 mute swans over 11 years. We achieved a mean annual statewide cull rate of 0.15 and reduced the 2005 mute swan population 56% by 2017. The statewide mute swan population declined (<i>P</i> = 0.038) at nearly 8%/yr following commencement of culls. Four heavily used molting sites comprised 79% of the mute swans culled and population response varied across the 4 key cull sites. We fit a linear model using a derived annual cull rate and mute swan abundance data to describe the effect of culls on population growth (λ) and determined that a cull rate >0.09 was required to reduce (λ < 1) the mute swan population in New Jersey. Our work should benefit wildlife agencies who are considering implementing mute swan management programs.","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"7 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael A. Powell, Sarah A. Brown, Robin M. Rotman, Sonja A. Wilhelm Stanis
In a response to our article, Brown, et al. (2023), Bennett and Brammer (2023) questioned our recommendation to increase the usage of affirmative language in conservation easements, enumerating their 4 concerns with affirmative clauses in easement language, and recommending habitat leasing as a better alternative. We are in full agreement with the potential value of habitat leasing for biodiversity protection; however, we disagree with its utility as a replacement for affirmative language, as well as the logic underpinning that assertion. Instead, we suggest an approach integrating both tools to minimize cost concerns and maximize the benefits of effective habitat management for biodiversity.
Brown 等人（2023 年）、Bennett 和 Brammer（2023 年）在对我们文章的回复中质疑我们关于在保护地役权中增加肯定性语言使用的建议，列举了他们对地役权语言中肯定性条款的 4 点担忧，并建议将生境租赁作为更好的替代方案。我们完全同意栖息地租赁对保护生物多样性的潜在价值；但我们不同意用栖息地租赁来替代肯定性语言，也不同意这种说法所依据的逻辑。相反，我们建议采用一种将两种工具结合起来的方法，以最大限度地减少成本问题，并最大限度地提高有效生境管理对生物多样性的益处。
{"title":"Supplement to conservation easements, not replacement, is the appropriate role of habitat leasing","authors":"Michael A. Powell, Sarah A. Brown, Robin M. Rotman, Sonja A. Wilhelm Stanis","doi":"10.1002/wsb.1508","DOIUrl":"https://doi.org/10.1002/wsb.1508","url":null,"abstract":"<p>In a response to our article, Brown, et al. (<span>2023</span>), Bennett and Brammer (<span>2023</span>) questioned our recommendation to increase the usage of affirmative language in conservation easements, enumerating their 4 concerns with affirmative clauses in easement language, and recommending habitat leasing as a better alternative. We are in full agreement with the potential value of habitat leasing for biodiversity protection; however, we disagree with its utility as a replacement for affirmative language, as well as the logic underpinning that assertion. Instead, we suggest an approach integrating both tools to minimize cost concerns and maximize the benefits of effective habitat management for biodiversity.</p>","PeriodicalId":23845,"journal":{"name":"Wildlife Society Bulletin","volume":"08 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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