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Abstract Because foundation species create structure in a community, understanding their ecological and evolutionary responses to global change is critical for predicting the ecological and economic management of species and communities that rely on them. Giant kelp (Macrocystis pyrifera) is a globally distributed foundation species with seasonal fluctuations in abundance in response to local nutrient levels, storm intensity, and ocean temperatures. Here we examine genetic variation in individual and population‐level responses of early life history stages (zoospore settlement, survival, and gametogenesis) to increased temperatures to determine the potential for natural selection on temperature‐tolerant individuals that would allow adaptation to a changing climate. We collected fertileM. pyriferasporophyll blades from three sites along the California coast (Los Angeles, Santa Barbara, Monterey Bay) and induced zoospore release in the lab. Spores settled on microscope slides at three treatment temperatures (16, 20, and 22°C), matured for 21 days, and were imaged weekly to determine settlement, survival, and maturation success. On average, individuals from all sites showed lower rates of settlement and maturation in response to increasing temperature. However, the magnitude of the responses to temperature varied among populations. Survival tended to increase with temperature in Los Angeles and Santa Barbara populations but decreased with increasing temperature for the Monterey Bay population. We observed little genetic variation in temperature responses among individuals within sites, suggesting little scope for evolution within populations to increase the resilience ofM. pyriferapopulations to warming ocean temperatures and predicted declines in kelp abundance. Yet sufficient dispersal among populations could allow for adaptation of early life history traits among populations via evolutionary rescue of declining populations.
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This content will become publicly available on July 7, 2026
Post‐release settlement and resource selection by reintroduced Swift fox
Monitoring post‐release dispersal of reintroduced wildlife informs management strategies to improve outcomes. In previous Swift fox (Vulpes velox) reintroductions, post‐release movements corresponded with survival and have been a metric for success of release strategies, but settlement patterns and resource selection by individuals from different source locations have not been compared. We fit piecewise regression models and resource selection functions to Global Positioning System collar data from Swift fox translocated to the Fort Belknap Reservation from Colorado and Wyoming. We found that 76% of studied Swift fox settled, most within 20 km of their release site. Contrary to our predictions, rates of settlement, distance and time to settlement, and resource selection did not differ by cohort or release strategy. Where Swift fox settled, we observed consistent selection of areas with high percentage cover by grass, low terrain ruggedness, intermediate clay soil content, and high Black‐tailed prairie dog suitability. Collectively, our study suggests that Swift fox are adaptable to a range of conditions within grassland ecosystems when high quality habitat is available and when pre‐release husbandry protocols are followed. However, we observed variability in post‐release behavior unexplained by the factors we assessed, possibly attributable to individual personality differences that are well documented in small canids. Swift fox are the most intensively reintroduced canid in the world, and our study highlights how science‐based advances in reintroduction practices can enhance success over time. These advances are particularly effective on Indigenous Peoples' Land, where high ecological and social suitability is present for large‐scale restoration initiatives.
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- Award ID(s):
- 2054877
- PAR ID:
- 10621463
- Publisher / Repository:
- Wiley Periodicals LLC
- Date Published:
- Journal Name:
- Restoration Ecology
- ISSN:
- 1061-2971
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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