Tilde Katrina Slotte Hjermann, Nikolai Antonsen Bilet, I. M. Rivrud, Erling L. Meisingset, P. Thorvaldsen, A. Mysterud
Grazing by wildlife on agricultural land is widespread across geographical regions, and can cause human–wildlife conflicts due to reduced crop yield when the grazing pressure is high. Growing red deer Cervus elaphus populations in Europe call for an increased understanding of their grazing patterns to mitigate damages. We quantified how red deer grazing pressure (grazing presence and grazing level) on agricultural grass meadows (n = 60) in Norway varied across multiple spatial scales. We used a nested, hierarchical study design transcending from a broad scale (meadows across the landscape) to intermediate (between nearby meadows) and local (within‐meadow) scales, allowing us to identify at which scale the variation in grazing pressure was strongest. We estimated how grazing was determined by broad‐scale factors influencing forage availability and quality through population density, distance to coastline, and differences between the first versus second harvest, by intermediate‐scale factors in terms of meadow management causing differences in botanical composition and quality, and by local‐scale factors in terms of perceived predation risk and disturbance. At a broad scale, higher population densities were associated with higher grazing pressure, and more grazing occurred before the first compared to the second harvest. Intermediate‐scale factors explained the most variation of grazing pressure from red deer, with higher grazing pressure on newly renewed meadows compared to other nearby meadows. On a local scale, more grazing occurred closer to the forest edge, providing cover, and further away from infrastructure, with increased risk and disturbance. Overall, our study highlights how drivers of grazing pressure on agricultural land vary across spatial scales. Population reductions on a broader scale may have some effect in reducing the grazing pressure, but renewed meadows will nevertheless attract red deer, causing higher grazing pressure compared to neighbouring meadows. This insight is crucial for determining effective mitigation strategies facing rising red deer populations across Europe.
{"title":"Red deer grazing pressure on agricultural grass meadows from broad to local scale","authors":"Tilde Katrina Slotte Hjermann, Nikolai Antonsen Bilet, I. M. Rivrud, Erling L. Meisingset, P. Thorvaldsen, A. Mysterud","doi":"10.1002/wlb3.01312","DOIUrl":"https://doi.org/10.1002/wlb3.01312","url":null,"abstract":"Grazing by wildlife on agricultural land is widespread across geographical regions, and can cause human–wildlife conflicts due to reduced crop yield when the grazing pressure is high. Growing red deer Cervus elaphus populations in Europe call for an increased understanding of their grazing patterns to mitigate damages. We quantified how red deer grazing pressure (grazing presence and grazing level) on agricultural grass meadows (n = 60) in Norway varied across multiple spatial scales. We used a nested, hierarchical study design transcending from a broad scale (meadows across the landscape) to intermediate (between nearby meadows) and local (within‐meadow) scales, allowing us to identify at which scale the variation in grazing pressure was strongest. We estimated how grazing was determined by broad‐scale factors influencing forage availability and quality through population density, distance to coastline, and differences between the first versus second harvest, by intermediate‐scale factors in terms of meadow management causing differences in botanical composition and quality, and by local‐scale factors in terms of perceived predation risk and disturbance. At a broad scale, higher population densities were associated with higher grazing pressure, and more grazing occurred before the first compared to the second harvest. Intermediate‐scale factors explained the most variation of grazing pressure from red deer, with higher grazing pressure on newly renewed meadows compared to other nearby meadows. On a local scale, more grazing occurred closer to the forest edge, providing cover, and further away from infrastructure, with increased risk and disturbance. Overall, our study highlights how drivers of grazing pressure on agricultural land vary across spatial scales. Population reductions on a broader scale may have some effect in reducing the grazing pressure, but renewed meadows will nevertheless attract red deer, causing higher grazing pressure compared to neighbouring meadows. This insight is crucial for determining effective mitigation strategies facing rising red deer populations across Europe.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141919866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sabina Nowak, Patrycja Tomczak, Aleksandra Kraśkiewicz, Jacek Więckowski, Katarzyna Tołkacz, Weronika Baranowska, Antoni Kasprzak, R. Mysłajek
We assessed the diet composition of wolves inhabiting Notecka Forest (ca 1400 km2) in western Poland based on the analysis of scats (n = 261) collected in 2008–2021. The study revealed that wolves in this large forest tract, consisting mainly of pine monocultures, consumed primarily wild ungulates (95.2% of consumed biomass). The roe deer was the essential food item (47.8%), followed by the red deer Cervus elaphus (25.1%) and the wild boar Sus scrofa) (18.4%). Wolves supplemented their diet with medium‐sized wild mammals, mainly the European hare Lepus europaeus (2.8%) and the Eurasian beaver Castor fiber (1.9%). The food niche was narrow (B = 1.1), and there was no difference in food composition between the spring–summer and autumn–winter seasons. We emphasize the significance of the smallest European wild ruminant, roe deer, in the diet of wolves inhabiting Central European Plains.
{"title":"Wolf diet in the Notecka Forest, western Poland","authors":"Sabina Nowak, Patrycja Tomczak, Aleksandra Kraśkiewicz, Jacek Więckowski, Katarzyna Tołkacz, Weronika Baranowska, Antoni Kasprzak, R. Mysłajek","doi":"10.1002/wlb3.01224","DOIUrl":"https://doi.org/10.1002/wlb3.01224","url":null,"abstract":"We assessed the diet composition of wolves inhabiting Notecka Forest (ca 1400 km2) in western Poland based on the analysis of scats (n = 261) collected in 2008–2021. The study revealed that wolves in this large forest tract, consisting mainly of pine monocultures, consumed primarily wild ungulates (95.2% of consumed biomass). The roe deer was the essential food item (47.8%), followed by the red deer Cervus elaphus (25.1%) and the wild boar Sus scrofa) (18.4%). Wolves supplemented their diet with medium‐sized wild mammals, mainly the European hare Lepus europaeus (2.8%) and the Eurasian beaver Castor fiber (1.9%). The food niche was narrow (B = 1.1), and there was no difference in food composition between the spring–summer and autumn–winter seasons. We emphasize the significance of the smallest European wild ruminant, roe deer, in the diet of wolves inhabiting Central European Plains.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Statistical population reconstruction (SPR) models have emerged as a robust and versatile framework for estimating the demographic dynamics of harvested wildlife populations using commonly collected age‐at‐harvest and catch‐effort data. Although numerous studies have suggested that higher interannual variability in catch effort may improve the accuracy and precision of reconstructed estimates, particularly in the absence of auxiliary data on annual abundance or survival, the extent and magnitude of these effects has not been explored. We examined the influence of catch‐effort variability, as measured by the ratio between years of highest and lowest effort, on the relative absolute deviation of reconstructed estimates of population abundance, as well as on the actual percent coverage and width of the corresponding confidence intervals. We used a Monte Carlo simulation to generate catch‐effort data with different levels of variability for populations experiencing a wide range of demographic and harvest conditions. For similar amounts of age‐at‐harvest data, using catch‐effort data with higher interannual variability resulted in reconstructed estimates of annual abundance that had significantly lower deviations from reality, better coverage, and narrower confidence intervals (as measured by the margin of error). These improvements were consistent and linear at low to medium levels of catch‐effort variability, but leveled off and became substantially less pronounced at higher levels. We found that the inclusion of auxiliary data largely mediated this relationship, although higher catch‐effort variability still resulted in more accurate and precise estimates of annual abundance even when these data were included. Our research highlights the need to include a thorough investigation of the available catch‐effort data alongside the established practices of assessing the number of years of available data, the average number of animals harvested each year, and the availability of auxiliary data from radio‐telemetry studies or other sources.
{"title":"The effects of variability in catch effort on the precision of statistical population reconstruction","authors":"Sergey S. Berg, John D. Erb, Abby K. Westphal","doi":"10.1002/wlb3.01288","DOIUrl":"https://doi.org/10.1002/wlb3.01288","url":null,"abstract":"Statistical population reconstruction (SPR) models have emerged as a robust and versatile framework for estimating the demographic dynamics of harvested wildlife populations using commonly collected age‐at‐harvest and catch‐effort data. Although numerous studies have suggested that higher interannual variability in catch effort may improve the accuracy and precision of reconstructed estimates, particularly in the absence of auxiliary data on annual abundance or survival, the extent and magnitude of these effects has not been explored. We examined the influence of catch‐effort variability, as measured by the ratio between years of highest and lowest effort, on the relative absolute deviation of reconstructed estimates of population abundance, as well as on the actual percent coverage and width of the corresponding confidence intervals. We used a Monte Carlo simulation to generate catch‐effort data with different levels of variability for populations experiencing a wide range of demographic and harvest conditions. For similar amounts of age‐at‐harvest data, using catch‐effort data with higher interannual variability resulted in reconstructed estimates of annual abundance that had significantly lower deviations from reality, better coverage, and narrower confidence intervals (as measured by the margin of error). These improvements were consistent and linear at low to medium levels of catch‐effort variability, but leveled off and became substantially less pronounced at higher levels. We found that the inclusion of auxiliary data largely mediated this relationship, although higher catch‐effort variability still resulted in more accurate and precise estimates of annual abundance even when these data were included. Our research highlights the need to include a thorough investigation of the available catch‐effort data alongside the established practices of assessing the number of years of available data, the average number of animals harvested each year, and the availability of auxiliary data from radio‐telemetry studies or other sources.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141816668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marina Cracco, A. H. Michel, Franziska Komossa, Inhye Kong, Norman Backhaus, Lucia Thaler, Timo Oliveri, Gretchen Walters
This article presents our recent experience studying public perceptions, discourses, and social values in Park Beverin, a Regional Nature Park in Switzerland. We applied four social research methods (news media analysis, survey with micro‐narratives, go‐along interviews, and focus groups), and delved into the subject of wolf Canis lupus adapting a triangulation protocol and systematic process from the health sciences. We observed the recurring perceptions of ‘wolf' throughout three of the four methods; however, depictions, values, prominence, and presence varied by method. Social values of the wolf were mostly silent when compared to other topics, and ‘wolf amplification' and ‘wolf fatigue' point to the need to rethink the social aspects in wolf management, conservation, and policy. The findings also show the need for diverse research methods for revealing social values and perceptions on sensitive topics that otherwise the use of one method may be masking or amplifying.
{"title":"Where is the wolf? A multi‐method comparison of social values and perceptions in a Swiss park","authors":"Marina Cracco, A. H. Michel, Franziska Komossa, Inhye Kong, Norman Backhaus, Lucia Thaler, Timo Oliveri, Gretchen Walters","doi":"10.1002/wlb3.01267","DOIUrl":"https://doi.org/10.1002/wlb3.01267","url":null,"abstract":"This article presents our recent experience studying public perceptions, discourses, and social values in Park Beverin, a Regional Nature Park in Switzerland. We applied four social research methods (news media analysis, survey with micro‐narratives, go‐along interviews, and focus groups), and delved into the subject of wolf Canis lupus adapting a triangulation protocol and systematic process from the health sciences. We observed the recurring perceptions of ‘wolf' throughout three of the four methods; however, depictions, values, prominence, and presence varied by method. Social values of the wolf were mostly silent when compared to other topics, and ‘wolf amplification' and ‘wolf fatigue' point to the need to rethink the social aspects in wolf management, conservation, and policy. The findings also show the need for diverse research methods for revealing social values and perceptions on sensitive topics that otherwise the use of one method may be masking or amplifying.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141814736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent decades have seen a dramatic increase in research publications in wildlife biology, the results add or subtract weights for a particular claim. However, we propose that there is an acute need for a post‐publication evaluation of research beyond peer review. The number of publications, not their content, has long been the most important index of scientific competence, and the pursuit of high publication rates has greatly affected how we teach, conduct research, and engage in the process of knowledge transfer. It is time to move away from publication metrics and embrace a more holistic assessment to remain relevant and deliver on societal needs. Extensive field experience is required to understand the limitations of different methods, study designs, and data collection. Unfortunately, publications based on fieldwork are declining, whereas those based on modelling and data analyses are increasing. The focus on publication rates and pressure to complete degrees within stipulated time has made fieldwork‐based studies nearly impossible. We firmly believe that this is a dangerous development, and we argue for increased attention to fieldwork and empirical training. Students should enter the environments in which they are studying, collect and analyse real data, and apply ecological inference. We see a risk that research questions become restricted by the way research projects and PhD projects are organised, often one researcher ‐ one project, typically funded for three years. We propose that funding agencies should embrace larger projects to undertake longer‐term and wider geographic scale studies and better support interdisciplinary research to address many of the more complex applied problems. Publishers, funders, and promotion boards should credit researcher input that engages in knowledge transfer to practitioners. In Europe, there are agencies and NGOs that should have an interest in supporting the process to collate and implement the best available knowledge.
{"title":"Reaching and implementing the best available knowledge in wildlife biology","authors":"Tomas Willebrand, Scott Newey","doi":"10.1002/wlb3.01307","DOIUrl":"https://doi.org/10.1002/wlb3.01307","url":null,"abstract":"Recent decades have seen a dramatic increase in research publications in wildlife biology, the results add or subtract weights for a particular claim. However, we propose that there is an acute need for a post‐publication evaluation of research beyond peer review. The number of publications, not their content, has long been the most important index of scientific competence, and the pursuit of high publication rates has greatly affected how we teach, conduct research, and engage in the process of knowledge transfer. It is time to move away from publication metrics and embrace a more holistic assessment to remain relevant and deliver on societal needs. Extensive field experience is required to understand the limitations of different methods, study designs, and data collection. Unfortunately, publications based on fieldwork are declining, whereas those based on modelling and data analyses are increasing. The focus on publication rates and pressure to complete degrees within stipulated time has made fieldwork‐based studies nearly impossible. We firmly believe that this is a dangerous development, and we argue for increased attention to fieldwork and empirical training. Students should enter the environments in which they are studying, collect and analyse real data, and apply ecological inference. We see a risk that research questions become restricted by the way research projects and PhD projects are organised, often one researcher ‐ one project, typically funded for three years. We propose that funding agencies should embrace larger projects to undertake longer‐term and wider geographic scale studies and better support interdisciplinary research to address many of the more complex applied problems. Publishers, funders, and promotion boards should credit researcher input that engages in knowledge transfer to practitioners. In Europe, there are agencies and NGOs that should have an interest in supporting the process to collate and implement the best available knowledge.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141824163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Elena Iannino, J. Linnell, Olivier Devineau, J. Odden, J. Mattisson, Neri Horntvedt Thorsen
The diel activity patterns of animals convey information about physiology, ecological niches and animal behaviour relevant for both applied conservation and more theoretical research. However, these patterns are challenging to study in the field. The current gold‐standard approach to quantify movements and activity patterns of medium to large wildlife species is to use global positioning systems (GPS) collars equipped with activity sensors (e.g. accelerometers). A more recent approach consists of inferring activity patterns from the time‐stamped pictures of wildlife obtained from camera traps now routinely used in wildlife monitoring projects. However, few studies have attempted to validate estimates of activity patterns obtained from camera traps against those obtained from activity sensors. In this study, we compared the diel activity pattern of the Eurasian lynx Lynx lynx inferred from detections by a network of over 300 camera traps active between 2010 and 2020, to activity patterns obtained from 18 GPS‐collared lynx (8 females, 10 males) equipped with 2‐axis accelerometer sensors, in the same area of southern Norway. Our results suggest that camera traps can be used to estimate diel activity curves that are comparable to those obtained from accelerometers. In our study, 75 detections were sufficient to approximate the diel activity pattern obtained from accelerometer. Subsampling indicated that a low number of detections results in a coarser approximation of the diel activity pattern.
{"title":"Assessing the potential of camera traps for estimating activity pattern compared to collar‐mounted activity sensors: a case study on Eurasian lynx Lynx lynx in south‐eastern Norway","authors":"Elena Iannino, J. Linnell, Olivier Devineau, J. Odden, J. Mattisson, Neri Horntvedt Thorsen","doi":"10.1002/wlb3.01263","DOIUrl":"https://doi.org/10.1002/wlb3.01263","url":null,"abstract":"The diel activity patterns of animals convey information about physiology, ecological niches and animal behaviour relevant for both applied conservation and more theoretical research. However, these patterns are challenging to study in the field. The current gold‐standard approach to quantify movements and activity patterns of medium to large wildlife species is to use global positioning systems (GPS) collars equipped with activity sensors (e.g. accelerometers). A more recent approach consists of inferring activity patterns from the time‐stamped pictures of wildlife obtained from camera traps now routinely used in wildlife monitoring projects. However, few studies have attempted to validate estimates of activity patterns obtained from camera traps against those obtained from activity sensors. In this study, we compared the diel activity pattern of the Eurasian lynx Lynx lynx inferred from detections by a network of over 300 camera traps active between 2010 and 2020, to activity patterns obtained from 18 GPS‐collared lynx (8 females, 10 males) equipped with 2‐axis accelerometer sensors, in the same area of southern Norway. Our results suggest that camera traps can be used to estimate diel activity curves that are comparable to those obtained from accelerometers. In our study, 75 detections were sufficient to approximate the diel activity pattern obtained from accelerometer. Subsampling indicated that a low number of detections results in a coarser approximation of the diel activity pattern.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141640438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katie L. Anderson, D. E. Spalinger, William B. Collins
The Nelchina Basin, located west of Glenallen, AK provides important moose Alces alces habitat throughout the year. However, previous research in this area has shown that the moose populations appear to be nutritionally limited by the available forage. The Nelchina Basin was deemed an intensive management unit to increase moose populations through predator control efforts and prescribed fires to increase the amount of available forage, including the 2004 Alphabet Hills fire. We quantified the available digestible energy (DE) and digestible protein (DP) during the summer of 2018 and 2019, as well as the winter in between, and availability of forages for moose within the burn perimeter and the adjacent unburned forest during the summer of 2019. We found that total canopy cover of the primary forage species was lower in the burned areas than in the adjacent unburned forest habitats, but only by 1%. Summer DP was significantly impacted by burn/unburn, caused by a 6% difference between the burn (avg = 2.58%) and the forest (avg = 2.43%). We also found a significant difference in DE and DP across the two sampling years. Although others have shown a positive effect of wildfire for herbivore populations, we found that the Alphabet Hills fire may not have made as much of a positive impact as in other systems. This project highlights the importance of research that quantifies both the availability of and the quantity of available food resources for herbivores.
{"title":"Prescribed fire in the Nelchina Basin: a case study for managing moose population","authors":"Katie L. Anderson, D. E. Spalinger, William B. Collins","doi":"10.1002/wlb3.01315","DOIUrl":"https://doi.org/10.1002/wlb3.01315","url":null,"abstract":"The Nelchina Basin, located west of Glenallen, AK provides important moose Alces alces habitat throughout the year. However, previous research in this area has shown that the moose populations appear to be nutritionally limited by the available forage. The Nelchina Basin was deemed an intensive management unit to increase moose populations through predator control efforts and prescribed fires to increase the amount of available forage, including the 2004 Alphabet Hills fire. We quantified the available digestible energy (DE) and digestible protein (DP) during the summer of 2018 and 2019, as well as the winter in between, and availability of forages for moose within the burn perimeter and the adjacent unburned forest during the summer of 2019. We found that total canopy cover of the primary forage species was lower in the burned areas than in the adjacent unburned forest habitats, but only by 1%. Summer DP was significantly impacted by burn/unburn, caused by a 6% difference between the burn (avg = 2.58%) and the forest (avg = 2.43%). We also found a significant difference in DE and DP across the two sampling years. Although others have shown a positive effect of wildfire for herbivore populations, we found that the Alphabet Hills fire may not have made as much of a positive impact as in other systems. This project highlights the importance of research that quantifies both the availability of and the quantity of available food resources for herbivores.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141655230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jacob Mueti Ngwava, F. Xiao, P. Malonza, Beryl A. Bwong, Hai‐Tao Shi
Reproduction of the pancake tortoise in the wild has remained poorly known over the decades. This study fills the knowledge gap by investigating the reproductive ecology of the species in its natural habitats in Kenya. Data were collected using the time‐constrained search‐and‐seize method, group‐level scan sampling, radio tracking, and camera‐trapping. Our observations revealed a total of 19 mating events that occurred between December and April, predominantly during the rainy seasons. Mating duration averaged 15.2 ± 2.4 min. Male–male aggression was observed during the mating season, with the dominant male keeping off all other males and mating with the resident females. Nest preparation events occurred between April and June. Nine nesting events were recorded, but in only five of them was an egg deposited. The nests were dug in loose soil, appeared almost circular, and measured 8.4 ± 0.9 cm wide and 7.0 ± 0.1 cm deep (n = 7). The average clutch size was one egg. The eggs were white, hard‐shelled, oval, and elongated measuring 4.4 ± 0.4 cm long, 2.7 ± 0.04 cm wide and weighed 17 ± 0.6 g (n = 3). Incubation period lasted 177 ± 5.7 days (n = 2), and hatching coincided with the onset of the short rainy season in November, aligned with the availability of abundant food for the tortoises. The hatchlings were minimally wider than long, having an average straight carapace length of 4.5 ± 0.6 cm, an average width of 4.5 ± 0.4 cm, and on average weighed 14.7 ± 3.7g, (n = 9). They remained near the nest site for 4–5 days before relocating to tiny rock crevices away from the adult tortoise crevices. Egg and hatchling predation was high, with four of the total of six eggs, observed after they were laid, being destroyed. Three juveniles, out of nine, were also eaten by predators. These findings contribute useful information for the formulation of effective conservation and management strategies for this critically endangered species.
{"title":"Reproductive ecology of the critically endangered pancake tortoise (Malacochersus tornieri) in the wild","authors":"Jacob Mueti Ngwava, F. Xiao, P. Malonza, Beryl A. Bwong, Hai‐Tao Shi","doi":"10.1002/wlb3.01181","DOIUrl":"https://doi.org/10.1002/wlb3.01181","url":null,"abstract":"Reproduction of the pancake tortoise in the wild has remained poorly known over the decades. This study fills the knowledge gap by investigating the reproductive ecology of the species in its natural habitats in Kenya. Data were collected using the time‐constrained search‐and‐seize method, group‐level scan sampling, radio tracking, and camera‐trapping. Our observations revealed a total of 19 mating events that occurred between December and April, predominantly during the rainy seasons. Mating duration averaged 15.2 ± 2.4 min. Male–male aggression was observed during the mating season, with the dominant male keeping off all other males and mating with the resident females. Nest preparation events occurred between April and June. Nine nesting events were recorded, but in only five of them was an egg deposited. The nests were dug in loose soil, appeared almost circular, and measured 8.4 ± 0.9 cm wide and 7.0 ± 0.1 cm deep (n = 7). The average clutch size was one egg. The eggs were white, hard‐shelled, oval, and elongated measuring 4.4 ± 0.4 cm long, 2.7 ± 0.04 cm wide and weighed 17 ± 0.6 g (n = 3). Incubation period lasted 177 ± 5.7 days (n = 2), and hatching coincided with the onset of the short rainy season in November, aligned with the availability of abundant food for the tortoises. The hatchlings were minimally wider than long, having an average straight carapace length of 4.5 ± 0.6 cm, an average width of 4.5 ± 0.4 cm, and on average weighed 14.7 ± 3.7g, (n = 9). They remained near the nest site for 4–5 days before relocating to tiny rock crevices away from the adult tortoise crevices. Egg and hatchling predation was high, with four of the total of six eggs, observed after they were laid, being destroyed. Three juveniles, out of nine, were also eaten by predators. These findings contribute useful information for the formulation of effective conservation and management strategies for this critically endangered species.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141658177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Holly Gamblin, David Green, Jesse Maestas, Andrew S. Bridges, D. Garcelon
On San Clemente Island (SCI), the island fox subspecies Urocyon littoralis clementae has been monitored annually since 1988 to track long‐term population trends. Annual density estimates in most habitat types across the island range from 2 to 13 foxes/km2, yet unusually high estimates have repeatedly approached 50 foxes/km2 in a unique sand dune habitat area. Although sand dune habitat is restricted to one small area on the island, these estimates suggest sand dune habitat supports one of the highest population densities of any fox species in the world, and it may support > 5% of the SCI fox population. This finding prompted our investigation to determine if SCI foxes captured in the sand dunes habitat area maintained home ranges within this habitat type. Between January and July 2018, we used global positioning system (GPS) collars to track the movements of 12 island foxes captured in the sand dune habitat area. Contrary to our initial predictions, we found that island foxes captured in the sand dune habitat area do maintain home ranges and core areas centralized in sand dune habitat. All 12 island fox home ranges estimated contained > 50% sand dune habitat in either their 50% or 95% fixed kernel density estimate (KDE) home range, and island foxes were 3.14 times more likely to use active sand dune habitat when compared to the second most abundant habitat type, maritime desert scrub (Adjusted β = 3.14, 95% CI = 3.07–3.12). We also found that island foxes in sand dune habitat maintained much smaller home ranges than reported estimates in other habitat types, with an average 95% KDE home range size of 0.42 km2 (95% CI = 0.20–0.63 km2). Although sand dune habitat comprises just 2% of available habitat on SCI, our research highlights the importance of this unique habitat area for island foxes.
{"title":"Patterns of island fox habitat use in sand dune habitat on San Clemente Island","authors":"Holly Gamblin, David Green, Jesse Maestas, Andrew S. Bridges, D. Garcelon","doi":"10.1002/wlb3.01330","DOIUrl":"https://doi.org/10.1002/wlb3.01330","url":null,"abstract":"On San Clemente Island (SCI), the island fox subspecies Urocyon littoralis clementae has been monitored annually since 1988 to track long‐term population trends. Annual density estimates in most habitat types across the island range from 2 to 13 foxes/km2, yet unusually high estimates have repeatedly approached 50 foxes/km2 in a unique sand dune habitat area. Although sand dune habitat is restricted to one small area on the island, these estimates suggest sand dune habitat supports one of the highest population densities of any fox species in the world, and it may support > 5% of the SCI fox population. This finding prompted our investigation to determine if SCI foxes captured in the sand dunes habitat area maintained home ranges within this habitat type. Between January and July 2018, we used global positioning system (GPS) collars to track the movements of 12 island foxes captured in the sand dune habitat area. Contrary to our initial predictions, we found that island foxes captured in the sand dune habitat area do maintain home ranges and core areas centralized in sand dune habitat. All 12 island fox home ranges estimated contained > 50% sand dune habitat in either their 50% or 95% fixed kernel density estimate (KDE) home range, and island foxes were 3.14 times more likely to use active sand dune habitat when compared to the second most abundant habitat type, maritime desert scrub (Adjusted β = 3.14, 95% CI = 3.07–3.12). We also found that island foxes in sand dune habitat maintained much smaller home ranges than reported estimates in other habitat types, with an average 95% KDE home range size of 0.42 km2 (95% CI = 0.20–0.63 km2). Although sand dune habitat comprises just 2% of available habitat on SCI, our research highlights the importance of this unique habitat area for island foxes.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141662321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Tiller, Tatyana Humle, Rajan Amin, Amie Humphries, Dave J. I. Seaman, Noah Sitati, Robert Smith
Habitat loss and fragmentation are two of the biggest threats facing wildlife today. Understanding the role of wildlife pathways in connecting resource areas is key for maintaining landscape connectivity, reducing the impacts of habitat loss and helping address human–wildlife conflict. In this study, we used sign surveys and camera trapping to understand the fine scale movement of elephants moving between a protected area and agricultural zone in the Masai Mara, Kenya. We used generalised linear models to determine factors driving high frequency of pathway use by elephants. Our results showed strong seasonal trends in pathway use, with peaks coinciding with the dry season. However, no correlations between rainfall and pathway use were found. Temporal patterns of pathway use indicate that elephants use risk avoidance strategies by moving between the two areas at times of low human disturbance. Spatial analysis revealed that the most frequently used pathways were closer to farms, saltlicks and forest and those that had a higher percentage of forest cover. Our models also showed a positive relationship between pathway use and the number of elephant crop raiding incidents, highlighting that pathways can play a role in human–elephant conflict. As habitat loss continues, pathways may become more important for linking resources. However, they are also likely to facilitate movement into farmland. The results from this study provide an opportunity for planned management activities to ensure connectivity and to mitigated conflict.
{"title":"Elephant pathway use in a human‐dominated landscape","authors":"L. Tiller, Tatyana Humle, Rajan Amin, Amie Humphries, Dave J. I. Seaman, Noah Sitati, Robert Smith","doi":"10.1002/wlb3.01204","DOIUrl":"https://doi.org/10.1002/wlb3.01204","url":null,"abstract":"Habitat loss and fragmentation are two of the biggest threats facing wildlife today. Understanding the role of wildlife pathways in connecting resource areas is key for maintaining landscape connectivity, reducing the impacts of habitat loss and helping address human–wildlife conflict. In this study, we used sign surveys and camera trapping to understand the fine scale movement of elephants moving between a protected area and agricultural zone in the Masai Mara, Kenya. We used generalised linear models to determine factors driving high frequency of pathway use by elephants. Our results showed strong seasonal trends in pathway use, with peaks coinciding with the dry season. However, no correlations between rainfall and pathway use were found. Temporal patterns of pathway use indicate that elephants use risk avoidance strategies by moving between the two areas at times of low human disturbance. Spatial analysis revealed that the most frequently used pathways were closer to farms, saltlicks and forest and those that had a higher percentage of forest cover. Our models also showed a positive relationship between pathway use and the number of elephant crop raiding incidents, highlighting that pathways can play a role in human–elephant conflict. As habitat loss continues, pathways may become more important for linking resources. However, they are also likely to facilitate movement into farmland. The results from this study provide an opportunity for planned management activities to ensure connectivity and to mitigated conflict.","PeriodicalId":54405,"journal":{"name":"Wildlife Biology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141846386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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