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Marine species worldwide are responding to ocean warming by shifting their ranges to new latitudes and, for intertidal species, elevations. Demographic traits can vary across populations spanning latitudinal and elevational ranges, with impacts on population growth. Understanding how demography varies across gradients from range center to edge could help us predict future shifts, species assemblages, and extinction risks. We investigated demographic traits for 2 range-expanding whelk species:Acanthinucella spirataandMexacanthina lugubris.We measured reproductive output across environmental (latitudinal and shore elevation) gradients along the coast of California, USA. We also conducted intensive measurements of offspring condition (survival and thermal tolerance) across shore elevation forM. lugubrisat one site. We found no difference in reproductive output, body size, or larval survival across shore heights forM. lugubris,suggesting that egg-laying behavior buffers developing stages from the relatively high level of thermal variation experienced due to daily tidal emersion. However, across latitudes, reproductive output increased toward the leading range edge forA. spirata, and body size increased for both species. Increased vital rates at the leading range edge could increase whelk population growth and expansion, allowing species to persist under climate change even if contractions occur at trailing edges.
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Climate‐driven range shifts of montane species vary with elevation
Abstract AimIn response to warming, species are shifting their ranges towards higher elevations. These elevational range shifts have been documented in a variety of taxonomic groups across latitude. However, the rate and direction of species range shifts in response to warming vary, potentially as a consequence of variation in species traits across elevation. Specifically, diurnal and seasonal climates are often more variable at higher elevations, which results in high‐elevation species that have broader thermal physiologies relative to low‐elevation species. High‐elevation species that are thermal generalists might not need to move as far to track their thermal niche as low‐elevation thermal specialists. We investigated whether rates of range shifts varied systematically with increasing elevation across taxa and regions. LocationSixteen montane regions world‐wide. Time period1850–2013. TaxonNine hundred and eighty‐seven species of plants and animals. MethodsWe gathered published data on elevational range shifts from 20 transect studies comparing historical and recent distributions and examined how rates of range shifts changed across elevation. Specifically, we performed a meta‐analysis to calculate the pooled effect of elevation on species range shifts. ResultsWe found that rates of range shifts show a negative relationship with elevation such that low‐elevation species have moved upslope farther than high‐elevation species on the same transect. This finding was primarily a result of shifts in the upper range limits. We also found that 28% of species shifted downslope against predictions, but elevation did not show a relationship with downslope range shifts. Main conclusionsIdiosyncratic range shifts will significantly alter montane ecological communities, which are home to some of the greatest biodiversity on Earth. Our results demonstrate that species range shifts vary with elevation and might be a consequence of differences in species traits that also vary along montane gradients.
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- Award ID(s):
- 1930829
- PAR ID:
- 10452479
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Ecology and Biogeography
- Volume:
- 30
- Issue:
- 4
- ISSN:
- 1466-822X
- Page Range / eLocation ID:
- p. 784-794
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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