Endemic Guadalupe bass (Micropterus treculii) are supported by isotopically distinct resources in tributary versus mainstem river food webs

Allison A. Pease; Jessica E. Pease; Preston T. Bean; Timothy B. Grabowski

doi:10.1002/rra.4015

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Endemic Guadalupe bass (Micropterus treculii) are supported by isotopically distinct resources in tributary versus mainstem river food webs

Allison A. Pease·Jessica E. Pease·Preston T. Bean·Timothy B. Grabowski

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Abstract

We used stable isotope analysis to investigate differences in Guadalupe bass ( Micropterus treculii ) resource use that might be associated with population-level variation in mainstem river versus tributary stream habitats. Guadalupe bass from mainstem sites had higher δ 13 C and δ 15 N values compared to those collected in tributaries, likely reflecting greater importance of algae as a basal resource and influences of urban wastewater in mainstem habitats. Documenting ecological variation across ecosystem types is important to inform fish conservation efforts, especially for species that occupy a range of stream sizes.

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Source-reported bounding extent: 29.252813907860016° to 32.59867803901426° latitude; -100.68408983430999° to -96.36083026967026° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Allison A. Pease, Jessica E. Pease, Preston T. Bean, Timothy B. Grabowski. 2022-06-23. Endemic Guadalupe bass (Micropterus treculii) are supported by isotopically distinct resources in tributary versus mainstem river food webs. https://doi.org/10.1002/rra.4015

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