Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix
Abstract Habitat loss and fragmentation are the leading causes of species range contraction and extirpation, worldwide. Factors that predict sensitivity to fragmentation include high trophic level, large body size, and extensive spatial requirements. Pumas (Puma concolor) exemplify these qualities,...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Wiley
2023-08-01
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| Series: | Ecology and Evolution |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ece3.10381 |
| _version_ | 1797732748272599040 |
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| author | David C. Stoner Zara McDonald Courtney A. C. Coon |
| author_facet | David C. Stoner Zara McDonald Courtney A. C. Coon |
| author_sort | David C. Stoner |
| collection | DOAJ |
| description | Abstract Habitat loss and fragmentation are the leading causes of species range contraction and extirpation, worldwide. Factors that predict sensitivity to fragmentation include high trophic level, large body size, and extensive spatial requirements. Pumas (Puma concolor) exemplify these qualities, making them particularly susceptible to fragmentation and subsequent reductions in demographic connectivity. The chaparral‐dominated ecosystems surrounding the greater San Francisco Bay Area encompass over 10,000 km2 of suitable puma habitat, but inland waterways, croplands, urban land uses, and extensive transportation infrastructure have resulted in widespread habitat fragmentation. Pumas in this region now exist as a metapopulation marked by loss of genetic diversity, collisions with vehicles, and extensive human–puma conflict. Given these trends, we conducted a photo survey from 2017 to 2021 across 19 patches of predicted habitat and compiled a dataset of >6584 puma images. We used a logistic regression analytical framework to evaluate the hypothesis that puma patch occupancy would exhibit a threshold response explained by patch size, isolation, and habitat quality. Contrary to predictions, only variables related to patch size demonstrated any power to explain occupancy. On average, occupied patches were 18× larger than those where they were not detected (825 ± 1238 vs. 46 ± 101 km2). Although we observed pumas in patches as small as 1 km2, logistic regression models indicated a threshold occupancy probability between 300 and 400 km2, which is remarkably close to the mean male puma home range size in coastal California (~381 km2). Puma populations dependent on habitats below this value may be susceptible to inbreeding depression and human–wildlife conflict, and therefore vulnerable to extirpation. For species conservation, we suggest conflicts might be ameliorated by identifying the largest, isolated patches for public education campaigns with respect to management of domestic animals, and remaining connective parcels be identified, mapped, and prioritized for targeted mitigation. |
| first_indexed | 2024-03-12T12:19:04Z |
| format | Article |
| id | doaj.art-be1877b0af9444f9952b97b9a8c8f700 |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-03-12T12:19:04Z |
| publishDate | 2023-08-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-be1877b0af9444f9952b97b9a8c8f7002023-08-30T06:50:40ZengWileyEcology and Evolution2045-77582023-08-01138n/an/a10.1002/ece3.10381Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrixDavid C. Stoner0Zara McDonald1Courtney A. C. Coon2Department of Wildland Resources Utah State University Logan Utah USAFelidae Conservation Fund Mill Valley California USAFelidae Conservation Fund Mill Valley California USAAbstract Habitat loss and fragmentation are the leading causes of species range contraction and extirpation, worldwide. Factors that predict sensitivity to fragmentation include high trophic level, large body size, and extensive spatial requirements. Pumas (Puma concolor) exemplify these qualities, making them particularly susceptible to fragmentation and subsequent reductions in demographic connectivity. The chaparral‐dominated ecosystems surrounding the greater San Francisco Bay Area encompass over 10,000 km2 of suitable puma habitat, but inland waterways, croplands, urban land uses, and extensive transportation infrastructure have resulted in widespread habitat fragmentation. Pumas in this region now exist as a metapopulation marked by loss of genetic diversity, collisions with vehicles, and extensive human–puma conflict. Given these trends, we conducted a photo survey from 2017 to 2021 across 19 patches of predicted habitat and compiled a dataset of >6584 puma images. We used a logistic regression analytical framework to evaluate the hypothesis that puma patch occupancy would exhibit a threshold response explained by patch size, isolation, and habitat quality. Contrary to predictions, only variables related to patch size demonstrated any power to explain occupancy. On average, occupied patches were 18× larger than those where they were not detected (825 ± 1238 vs. 46 ± 101 km2). Although we observed pumas in patches as small as 1 km2, logistic regression models indicated a threshold occupancy probability between 300 and 400 km2, which is remarkably close to the mean male puma home range size in coastal California (~381 km2). Puma populations dependent on habitats below this value may be susceptible to inbreeding depression and human–wildlife conflict, and therefore vulnerable to extirpation. For species conservation, we suggest conflicts might be ameliorated by identifying the largest, isolated patches for public education campaigns with respect to management of domestic animals, and remaining connective parcels be identified, mapped, and prioritized for targeted mitigation.https://doi.org/10.1002/ece3.10381Californiaconnectivitycougarextirpationfragmentationoccupancy |
| spellingShingle | David C. Stoner Zara McDonald Courtney A. C. Coon Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix Ecology and Evolution California connectivity cougar extirpation fragmentation occupancy |
| title | Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix |
| title_full | Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix |
| title_fullStr | Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix |
| title_full_unstemmed | Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix |
| title_short | Stepping stones to extirpation: Puma patch occupancy thresholds in an urban‐wildland matrix |
| title_sort | stepping stones to extirpation puma patch occupancy thresholds in an urban wildland matrix |
| topic | California connectivity cougar extirpation fragmentation occupancy |
| url | https://doi.org/10.1002/ece3.10381 |
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