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Abstract Lakeshore riparian habitats have undergone intensive residential development in many parts of the world. Lakeshore residential development (LRD) is associated with aquatic habitat loss/alteration, including altered macrophyte communities and reduced coarse woody habitat. Yet habitat‐mediated and other generalized effects of LRD on lake biotic communities are not well understood. We used two approaches to examine the relationships among LRD, habitat, and fish community in a set of 57 northern Wisconsin lakes. First, we examined how LRD affected aquatic habitat using mixed linear effects models. Second, we evaluated how LRD affected fish abundance and community structure at both whole‐lake and site‐level spatial scales using generalized linear mixed‐effects models. We found that LRD did not have a significant relationship with the total abundance (all species combined) of fish at either scale. However, there were significant species‐specific responses to LRD at the whole‐lake scale. Species abundances varied across the LRD gradient, with bluegill (Lepomis macrochirus) and mimic shiners (Notropis volucellus) responding positively along the gradient and walleye (Sander vitreus) having the most negative response. We also quantified site‐level habitat associations for each fish species. We found that habitat associations did not inform a species' overall response to LRD, as illustrated by species with similar responses to LRD having vastly different habitat associations. Finally, even with the inclusion of littoral habitat information in models, LRD still had significant effects on species abundances, reflecting a role of LRD in shaping littoral fish communities independent of our measure of littoral habitat alteration. Our results indicated that LRD altered littoral fish communities at the whole‐lake scale through both habitat and non‐habitat‐mediated drivers.
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Response of yellow perch to water level fluctuations in oligotrophic, north‐temperate inland lakes
Abstract Information on yellow perchPerca flavescenspopulation dynamics and responses to various abiotic and biotic factors in oligotrophic, north‐temperate inland lakes is limited. Water level fluctuations are known to influence available habitat and biological communities within the littoral zones of lakes, yet research is lacking for yellow perch in Wisconsin. The goal of our study was to characterize yellow perch population‐level responses to natural water level fluctuations in four northern Wisconsin lakes using a 39‐year time series. On average, increasing water level periods correlated with lower mean fyke net and gill net relative abundances (catch‐per‐unit‐effort), though generally not statistically significant. Yellow perch mean relative weight varied among lakes and was significantly greater during increasing water level periods for all lakes except one. The lack of statistically significant findings potentially suggests a buffering mechanism of north‐temperate oligotrophic lakes due to their small surface area to volume ratios, relative lack of nutrients, and(or) littoral structural habitat compared to other systems (e.g., shallow eutrophic lakes). Our results suggest that natural water level fluctuations may not be an environmental concern for yellow perch populations in some north‐temperate oligotrophic inland lakes.
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- Award ID(s):
- 2025982
- PAR ID:
- 10492688
- Publisher / Repository:
- Aquaculture, Fish and Fisheries
- Date Published:
- Journal Name:
- Aquaculture, Fish and Fisheries
- Volume:
- 4
- Issue:
- 1
- ISSN:
- 2693-8847
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/aff2.148
