Translator Disclaimer
1 September 2016 Food Habits of Sculpin Spp. in Small Idaho Streams: No Evidence of Predation on Newly Emerged Steelhead Alevins
Author Affiliations +
Abstract

Recent declines of anadromous salmonids in the Pacific Northwest have prompted a need to understand the factors limiting populations across habitats and life stages. In the weeks following emergence from the spawning gravel, juvenile salmonids have limited swimming capacity and can be particularly vulnerable to predation by piscivores, such as sculpins (Cottus sp.) which are widespread in Pacific Northwest streams. The objective of this study was to investigate the extent to which sculpin prey on newly emerged steelhead (Oncorhynchus mykiss) in a threatened population in Idaho. Three species of sculpin were present in the watershed, including Paiute (C. beldingii), mottled (C. bairdii), and torrent (C. rhotheus) sculpin. Gut content analyses of 360 sculpin showed that invertebrates were the dominant food source (> 85% of all sculpin preyed mainly on invertebrates), and piscivory was rare (< 2%). None of the samples contained steelhead alevins. We conclude that there was no indication of predation during emergence in our study system, but note that future studies should incorporate stable isotope analyses or directly investigate the extent to which sculpin prey on salmonid eggs.

© 2016 by the Northwest Scientific Association. All rights reserved.
Timothy N. Taylor, Knut Marius Myrvold, and Brian P. Kennedy "Food Habits of Sculpin Spp. in Small Idaho Streams: No Evidence of Predation on Newly Emerged Steelhead Alevins," Northwest Science 90(4), 484-490, (1 September 2016). https://doi.org/10.3955/046.090.0408
Received: 1 June 2015; Accepted: 1 June 2016; Published: 1 September 2016
JOURNAL ARTICLE
7 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top