The effects of temperature and predator densities on the consumption of walleye pollock (Gadus chalcogrammus) by three groundfish in the Gulf of Alaska Public Deposited

http://ir.library.oregonstate.edu/concern/articles/b5644t129

To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by NRC Research Press and can be found at:  http://www.nrcresearchpress.com/journal/cjfas.

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • Many multispecies models have assumed that prey density determines per-capita predator consumption rates, following a functional response relationship. However, empirical evidence suggests that a predator’s diet can also be influenced by a variety of environmental factors, including interactions with other predators. We used diet and abundance data from National Marine Fisheries Service (NMFS) bottom trawl surveys for three groundfish predators (Pacific cod (Gadus macrocephalus), Pacific halibut (Hippoglossus stenolepis), and sablefish (Anoplopoma fimbria)) in the Gulf of Alaska (GOA) to determine whether temperature or other species influence the consumption of walleye pollock (Gadus chalcogrammus). Using an information-theoretic approach, we tested for relationships between walleye pollock observed in predator stomachs and predator length, bottom temperature, prey availability (walleye pollock catch per unit effort (CPUE) scaled by observed prey lengths), and CPUE of the three predators and arrowtooth flounder (Atheresthes stomias). Predator length was positively related to walleye pollock presence and proportion of total diet mass in all predators. Increased temperatures negatively affected consumption of walleye pollock by Pacific halibut, but not the other predators. We found evidence for a number of interpredator effects of co-occurring predators, both positive (facultative) and negative (competitive). Surprisingly, observed prey density was not statistically significant with respect to consumption for these predators, suggesting that trawls sample the environment far differently than walleye pollock predators or species interactions are more complex than those used in previous multispecies models. These factors should be considered for future models contributing to ecosystem-based management.
Resource Type
DOI
Date Available
Date Issued
Citation
  • Thompson, K. A., Heppell, S. S., & Thompson, G. G. (2014). The effects of temperature and predator densities on the consumption of walleye pollock (Gadus chalcogrammus) by three groundfish in the Gulf of Alaska. Canadian Journal of Fisheries and Aquatic Sciences, 71(8), 1123-1133. doi:10.1139/cjfas-2013-0260
Series
Rights Statement
Funding Statement (additional comments about funding)
Publisher
Peer Reviewed
Language
Replaces
Additional Information
  • description.provenance : Made available in DSpace on 2014-10-09T16:53:02Z (GMT). No. of bitstreams: 1 ThompsonKevinFisheriesWildlifeEffectsTemperaturePredator.pdf: 1287746 bytes, checksum: 9fac1f141a4e5e9e3eac281e4b9ef586 (MD5) Previous issue date: 2014-08
  • description.provenance : Approved for entry into archive by Erin Clark(erin.clark@oregonstate.edu) on 2014-10-09T16:53:02Z (GMT) No. of bitstreams: 1 ThompsonKevinFisheriesWildlifeEffectsTemperaturePredator.pdf: 1287746 bytes, checksum: 9fac1f141a4e5e9e3eac281e4b9ef586 (MD5)
  • description.provenance : Submitted by Erin Clark (erin.clark@oregonstate.edu) on 2014-10-09T16:52:51Z No. of bitstreams: 1 ThompsonKevinFisheriesWildlifeEffectsTemperaturePredator.pdf: 1287746 bytes, checksum: 9fac1f141a4e5e9e3eac281e4b9ef586 (MD5)

Relationships

In Administrative Set:
Last modified: 07/26/2017

Downloadable Content

Download PDF
Citations:

EndNote | Zotero | Mendeley

Items