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This data set includes spatially explicit mark-recapture data of the Northern Spring Salamander (Gyrinophilus porphyriticus) collected via telemetry during the summer months (June – September) from 2019 - 2021 from eight reaches in multiple streams in the Hubbard Brook Experimental Forest. Salamanders were captured by hand and marked with PIT-tags. Telemetry surveys occurred weekly. 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 are being used to publish the following papers: Cochrane, M. M., B. R. Addis, L. K. Swartz, and W. H. Lowe. 2023. Individual and population growth rates decline with watershed area in a stream salamander. In review Ecology. Cochrane, M. M., and W. H. Lowe. 2023. Floods increase downstream movement of adult and larval life stages of a headwater stream salamander. In prep Freshwater Biology.
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This content will become publicly available on June 1, 2026
Headwater-stream salamander movements and home-range size increased under drought
Climate change is increasing the frequency and intensity of droughts and floods, which will likely have disproportionate effects on freshwater organisms. Stream salamanders are often top predators in small, fishless headwater streams that are highly responsive to hydrologic changes. Although these salamanders persist in dynamic stream environments, we lack the empirical understanding of how they respond to variable drought and flooding intensity that would allow us to predict future responses to climate-related changes in hydrology. We used 3 y (2019–2021) of data from passive integrated transponder (PIT)-tag surveys to characterize how movement distance, movement direction, and home-range size of the Northern Spring Salamander Gyrinophilus porphyriticus (Green, 1827) vary across a range of hydrologic conditions. Most notably, this PIT-tag data included a period of severe drought in the late summer of 2020. We found that total distance moved and home-range size increased with drought intensity. Total distance moved was not related to peak discharge at the range of flooding experienced across this study (<5-y flood recurrence intervals). Larval movements were skewed downstream after large floods but were skewed upstream across all other conditions. The direction of adult movements did not differ across extreme flood or drought conditions. Overall, adults moved greater distances and had larger home ranges than larvae (median movement = 1.9 m vs 1.6 m; median home range = 5 m2 vs 4 m2). We also found adults using moist terrestrial microhabitats for up to 14 consecutive days, even during moderate drought. Our results suggest that headwater salamanders will move more as drought intensity increases in the future. We interpret these movements as behavior used to find habitable, moist environments as stream reaches dry. These results suggest that adequate instream and riparian refuges will become more important for stream salamander survival as climate change progresses.
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- Award ID(s):
- 2224545
- PAR ID:
- 10650832
- Publisher / Repository:
- Freshwater Science
- Date Published:
- Journal Name:
- Freshwater Science
- Volume:
- 44
- Issue:
- 2
- ISSN:
- 2161-9549
- Page Range / eLocation ID:
- 159 to 169
- Format(s):
- Medium: X
- Associated Dataset(s):
- View Associated Dataset(s) >>
- Sponsoring Org:
- National Science Foundation
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We lack a strong understanding of how organisms with complex life histories respond to climate variation. Many stream-associated species have multi-stage life histories that are likely to influence the demographic consequences of floods and droughts. However, tracking stage specific demographic responses requires high-resolution, long-term data that are rare. We used eight years of capture-recapture data for the headwater stream salamander Gyrinophilus porphyriticus to quantify the effects of flooding and drying magnitude on stage-specific vital rates and population growth. Drying reduced larval recruitment but increased the probability of metamorphosis (i.e., adult recruitment). Flooding reduced adult recruitment but had no effect on larval recruitment. Larval and adult survival declined with flooding but were unaffected by drying. Annual population growth rates (lambda, ) declined with flooding and drying. Lambda also declined over the study period (2012 – 2021), although mean was 1.0 over this period. Our results indicate that G. porphyriticus populations are resilient to hydrologic variation due to compensatory effects on recruitment of larvae vs. adults (i.e., reproduction vs. metamorphosis). Complex life cycles may enable this resilience to climate variation by creating opportunities for compensatory demographic responses across stages. However, more frequent and intense hydrologic variation in the latter half of this study contributed to a decline in over time, suggesting that increasing environmental variability poses a threat even when demographic compensation occurs.more » « less
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{"Abstract":["This data set includes spatially explicit mark-recapture data of the\nNorthern Spring Salamander (Gyrinophilus porphyriticus) collected during\nthe summer months (June \u2013 August) from downstream and upstream reaches\nin multiple streams in the Hubbard Brook Experimental Forest. Downstream\nreaches begin at the confluence with the Main Hubbard and extend\nupstream 500 meters and upstream reaches begin at the weir and extend\ndownstream 500 meters. Downstream reaches contain brook trout and\nupstream reaches do not. We used a robust design framework with\napproximately 9 surveys per reach each summer (3 primary occasions with\n3 secondary occasions each). Salamanders were captured by hand and\nmarked with either Visual Implant Elastomer and/or a PIT tag.\n These data were gathered as part of the Hubbard Brook Ecosystem Study\n(HBES). The HBES is a collaborative effort at the Hubbard Brook\nExperimental Forest, which is operated and maintained by the USDA Forest\nService, Northern Research Station.\n These data have been published in the following papers: \n Lowe WH, Addis\nBR, Smith MR, Davenport JM. The spatial structure of variation in\nsalamander survival, body condition and morphology in a headwater stream\nnetwork. Freshwater Biol. 2018;63:1287\u20131299.\nhttps://doi.org/10.1111/fwb.13133\n Lowe, W. H., and Addis, B. R.. 2019. Matching habitat choice and plasticity contribute to phenotype\u2013environment covariation in a stream salamander. Ecology 100( 5):e02661. 10.1002/ecy.2661 \n 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.\n 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\n Addis, B.R., and W.H. Lowe. Environmentally associated variation in dispersal distance affects inbreeding risk in a stream salamander." The American Naturalist 2022."]}more » « less
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