Spatiotemporal Variation and Size‐Selective Predation on Hatchery‐ and Wild‐Born Juvenile Chum Salmon at Marine Entry by Nearshore Fishes in Southeast Alaska
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Spatiotemporal Variation and Size‐Selective Predation on Hatchery‐ and Wild‐Born Juvenile Chum Salmon at Marine Entry by Nearshore Fishes in Southeast Alaska

Filetype[PDF-637.57 KB]



Details:

  • Journal Title:
    Marine and Coastal Fisheries
  • Personal Author:
  • NOAA Program & Office:
  • Description:
    Juvenile Pacific salmon Oncorhynchus spp. experience high mortality at marine entry, yet our quantitative understanding of predation during this critical period is limited. We evaluated spatial, temporal, and size‐based patterns of predation on hatchery‐ and wild‐born juvenile Chum Salmon O. keta by two abundant predators in Southeast Alaska estuaries: the Pacific Staghorn Sculpin Leptocottus armatus and Dolly Varden Salvelinus malma. For the predators we sampled, Chum Salmon comprised 4.5% of the diet by weight for Pacific Staghorn Sculpin (n = 937) and 19.6% of the diet by weight for Dolly Varden (n = 448), with 88% of the individual Chum Salmon consumed originating from hatcheries. Variation in occurrence of Chum Salmon in diets was driven by date, site, and local Chum Salmon density. The quantity of Chum Salmon consumed by Pacific Staghorn Sculpin varied with predator length, Chum Salmon density, and the proportion of hatchery fish present; however, date was the only important predictor for Dolly Varden. The mean length of Chum Salmon in the diets of both predators was significantly shorter than that of concurrent hatchery releases or seine catches, suggesting size‐selective predation on smaller individuals. This pattern indicates that hatchery strategies of releasing larger individuals may reduce the initial vulnerability of hatchery salmon to estuarine predators.
  • Keywords:
  • Source:
    Marine and Coastal Fisheries, 11(5), 372-390
  • DOI:
  • ISSN:
    1942-5120;1942-5120;
  • Format:
  • Publisher:
  • Document Type:
  • Funding:
  • License:
  • Rights Information:
    CC BY
  • Compliance:
    Library
  • Main Document Checksum:
  • Download URL:
  • File Type:

You May Also Like

Checkout today's featured content at repository.library.noaa.gov

Version 3.26.1