This data set includes spatially explicit mark-recapture data of the Northern Spring Salamander (Gyrinophilus porphyriticus) collected during the summer months (June – August) from downstream and upstream reaches in multiple streams in the Hubbard Brook Experimental Forest. Downstream reaches begin at the confluence with the Main Hubbard and extend upstream 500 meters and upstream reaches begin at the weir and extend downstream 500 meters. Downstream reaches contain brook trout and upstream reaches do not. We used a robust design framework with approximately 9 surveys per reach each summer (3 primary occasions with 3 secondary occasions each). Salamanders were captured by hand and marked with either Visual Implant Elastomer and/or a PIT tag. These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station. These data have been published in the following papers: Lowe WH, Addis BR, Smith MR, Davenport JM. The spatial structure of variation in salamander survival, body condition and morphology in a headwater stream network. Freshwater Biol. 2018;63:1287–1299. https://doi.org/10.1111/fwb.13133 Lowe, W. H., and Addis, B. R.. 2019. Matching habitat choice and plasticity contribute to phenotype–environment covariation in a stream salamander. Ecology 100( 5):e02661. 10.1002/ecy.2661 Lowe, W.H., et al. Hydrologic variability contributes to reduced survival through metamorphosis in a stream salamander. Proceedings of the National Academy of Sciences 2019; 116.39: 19563-19570. Bryant, A.R., Gabor, C.R., Swartz, L.K., Wagner, R., Cochrane, M.M., Lowe, W.H. Differences in corticosterone release rates of larval Spring Salamanders (Gyrinophilus porphyriticus) in response to native fish presence. Biology 2022; 11.484. https://doi.org/10.3390/biology11040484 Addis, B.R., and W.H. Lowe. Environmentally associated variation in dispersal distance affects inbreeding risk in a stream salamander." The American Naturalist 2022.
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Long‐term survival probability, not current habitat quality, predicts dispersal distance in a stream salamander
Dispersal evolves as an adaptive mechanism to optimize individual fitness across the landscape. Specifically, dispersal represents a mechanism to escape fitness costs resulting from changes in environmental conditions. Decades of empirical work suggest that individuals use local habitat cues to make movement decisions, but theory predicts that dispersal can also evolve as a fixed trait, independent of local conditions, in environments characterized by a history of stochastic spatiotemporal variation. Until now, however, both conditional and fixed models of dispersal evolution have primarily been evaluated using emigration data (stay vs. leave), and not dispersal distances: a more comprehensive measure of dispersal. Our goal was to test whether conditional or fixed models of dispersal evolution predict variation in dispersal distance in the stream salamander
- Award ID(s):
- 1655653
- NSF-PAR ID:
- 10456589
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology
- Volume:
- 101
- Issue:
- 4
- ISSN:
- 0012-9658
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Across taxa, individuals vary in how far they disperse, with most individuals staying close to their origin and fewer dispersing long distances. Costs associated with dispersal (e.g., energy, risk) are widely believed to trade off with benefits (e.g., reduced competition, increased reproductive success) to influence dispersal propensity. However, this framework has not been applied to understand variation in dispersal distance, which is instead generally attributed to extrinsic environmental factors. We alternatively hypothesized that variation in dispersal distances results from trade‐offs associated with other aspects of locomotor performance. We tested this hypothesis in the stream salamander
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We found that average seed dispersal distance was lowest in the species that occupies the most spatiotemporally variable habitat, contradicting our predictions; however, inter‐seed spread was lowest in the species from the least variable habitat, which aligned with our expectations.
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