Seth M. Harju, Scott M. Cambrin, Stefanie Ferrazzano
{"title":"莫哈韦沙漠象龟(Gopherus agassizii)占用动态的短期植被驱动力","authors":"Seth M. Harju, Scott M. Cambrin, Stefanie Ferrazzano","doi":"10.1002/ecs2.70381","DOIUrl":null,"url":null,"abstract":"<p>Understanding the factors associated with the probability of a species occurring across the landscape has become a foundational component of wildlife management and monitoring. Static factors (e.g., plot characteristics that are consistent across time, such as topography or permanent woody vegetation) are often investigated, but changing vegetation factors may also drive apparent occupancy dynamics as energy-minimizing species respond to ephemeral changes in food resources. We analyzed the role of ephemeral forbs and grasses in the occupancy dynamics of Mojave desert tortoises (<i>Gopherus agassizii</i>), expecting higher occupancy when food plants (forbs) were abundant and lower occupancy when non-food plants (grasses) were widespread. We found that none of the static plot-level factors explained initial occupancy in the first year, but vegetation factors did influence interannual occupancy dynamics. Plots that were unoccupied in a given year were 14.4% less likely to become occupied in the following year for every 1% point increase in grass cover within the plot (i.e., a negative effect of grass cover on annual plot occupancy). Conversely, occupied plots were 72.5% less likely to become unoccupied in the subsequent year for every 1% point increase in the cover of forbs, and we unexpectedly found that occupied plots were 76.9% less likely to become unoccupied for every additional grass species present in the plot. However, credible intervals were wide, indicating strong but inconsistent patterns of ephemeral vegetation driving occupancy dynamics of Mojave desert tortoises.</p>","PeriodicalId":48930,"journal":{"name":"Ecosphere","volume":"16 8","pages":""},"PeriodicalIF":2.9000,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70381","citationCount":"0","resultStr":"{\"title\":\"Ephemeral vegetation drivers of occupancy dynamics of Mojave desert tortoises (Gopherus agassizii)\",\"authors\":\"Seth M. Harju, Scott M. Cambrin, Stefanie Ferrazzano\",\"doi\":\"10.1002/ecs2.70381\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Understanding the factors associated with the probability of a species occurring across the landscape has become a foundational component of wildlife management and monitoring. Static factors (e.g., plot characteristics that are consistent across time, such as topography or permanent woody vegetation) are often investigated, but changing vegetation factors may also drive apparent occupancy dynamics as energy-minimizing species respond to ephemeral changes in food resources. We analyzed the role of ephemeral forbs and grasses in the occupancy dynamics of Mojave desert tortoises (<i>Gopherus agassizii</i>), expecting higher occupancy when food plants (forbs) were abundant and lower occupancy when non-food plants (grasses) were widespread. We found that none of the static plot-level factors explained initial occupancy in the first year, but vegetation factors did influence interannual occupancy dynamics. Plots that were unoccupied in a given year were 14.4% less likely to become occupied in the following year for every 1% point increase in grass cover within the plot (i.e., a negative effect of grass cover on annual plot occupancy). Conversely, occupied plots were 72.5% less likely to become unoccupied in the subsequent year for every 1% point increase in the cover of forbs, and we unexpectedly found that occupied plots were 76.9% less likely to become unoccupied for every additional grass species present in the plot. However, credible intervals were wide, indicating strong but inconsistent patterns of ephemeral vegetation driving occupancy dynamics of Mojave desert tortoises.</p>\",\"PeriodicalId\":48930,\"journal\":{\"name\":\"Ecosphere\",\"volume\":\"16 8\",\"pages\":\"\"},\"PeriodicalIF\":2.9000,\"publicationDate\":\"2025-08-12\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/ecs2.70381\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Ecosphere\",\"FirstCategoryId\":\"93\",\"ListUrlMain\":\"https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.70381\",\"RegionNum\":3,\"RegionCategory\":\"环境科学与生态学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ECOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ecosphere","FirstCategoryId":"93","ListUrlMain":"https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.70381","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ECOLOGY","Score":null,"Total":0}
Ephemeral vegetation drivers of occupancy dynamics of Mojave desert tortoises (Gopherus agassizii)
Understanding the factors associated with the probability of a species occurring across the landscape has become a foundational component of wildlife management and monitoring. Static factors (e.g., plot characteristics that are consistent across time, such as topography or permanent woody vegetation) are often investigated, but changing vegetation factors may also drive apparent occupancy dynamics as energy-minimizing species respond to ephemeral changes in food resources. We analyzed the role of ephemeral forbs and grasses in the occupancy dynamics of Mojave desert tortoises (Gopherus agassizii), expecting higher occupancy when food plants (forbs) were abundant and lower occupancy when non-food plants (grasses) were widespread. We found that none of the static plot-level factors explained initial occupancy in the first year, but vegetation factors did influence interannual occupancy dynamics. Plots that were unoccupied in a given year were 14.4% less likely to become occupied in the following year for every 1% point increase in grass cover within the plot (i.e., a negative effect of grass cover on annual plot occupancy). Conversely, occupied plots were 72.5% less likely to become unoccupied in the subsequent year for every 1% point increase in the cover of forbs, and we unexpectedly found that occupied plots were 76.9% less likely to become unoccupied for every additional grass species present in the plot. However, credible intervals were wide, indicating strong but inconsistent patterns of ephemeral vegetation driving occupancy dynamics of Mojave desert tortoises.
期刊介绍:
The scope of Ecosphere is as broad as the science of ecology itself. The journal welcomes submissions from all sub-disciplines of ecological science, as well as interdisciplinary studies relating to ecology. The journal''s goal is to provide a rapid-publication, online-only, open-access alternative to ESA''s other journals, while maintaining the rigorous standards of peer review for which ESA publications are renowned.