Ecological Research

, Volume 24, Issue 5, pp 1091–1100 | Cite as

The ecology of terrestrial invertebrates on Pacific salmon carcasses

  • Morgan D. HockingEmail author
  • Richard A. Ring
  • Thomas E. Reimchen
Original Article


In coastal streams throughout the north Pacific region, spawning salmon (Oncorhynchus spp.) subsidize terrestrial communities with their nutrients and carcasses. We document the previously unreported composition and ecology of terrestrial invertebrates using salmon carcasses in forest habitats from two high salmon density watersheds in coastal British Columbia. From experimental placement of 186 carcasses, terrestrial Diptera-dominated salmon carcass decay (85.5% of carcasses). Overall, we recorded over 60 species from salmon carcasses, including saprophagous Diptera and Coleoptera (15 spp.), dipteran predators (eight spp.) and parasitoids (four spp.), and opportunistic predators, scavengers, and detritivores (24 spp.). Using stable isotopes of nitrogen and carbon, we reconstruct the dietary niches of select species relative to salmon muscle tissue and previously sampled non-salmon feeding invertebrate species. From comparisons across seasons, sampling locations and larval and adult life stages, we find evidence for a diet of salmon tissue in flies (Calliphora terraenovae and Dryomyza anilis), and beetles (Nicrophorus investigator and Anthobium fimetarium). The parasitic wasps Alysia alticola and Atractodes sp. had the highest levels of enrichment of all species, representing their larval diet of fly larvae that have fed on salmon carcasses 1 year prior to adult wasp sampling. Temporal and spatial isotopic variation in insect indicator species varies by species mobility and the pathway of salmon nutrient uptake. Cataloguing these associations may be useful for developing indices of intact salmon runs, bear foraging, and subsequent nutrient transfer in coastal watersheds.


Salmon ecosystems Stable isotopes Invertebrate assemblage Spatial and temporal variation Ecological role 



Thanks to C. Brinkmeier, K. Christie, C. Darimont, B. Foster, T. Gladstone, R. Hocking, S. Hocking, R. Johnson, L. Jorgenson, K. Petkau, C. Wilkinson, B. Windsor, D. Windsor, and M. Windsor, as well as the Raincoast Conservation Society and the Heiltsuk First Nations for field support. Thanks to all invertebrate taxonomists for identifications, M. Durban and J. Wray from Blue Fjord Charters, E. Darling, W. Palen and Z. Lindo for review comments, B. Hawkins at the University of Victoria, J. Reynolds at Simon Fraser University, and M. Stocki for stable isotope analysis at the University of Saskatchewan. Financial support was provided by grants to T. Reimchen from the David Suzuki Foundation and the Natural Sciences and Engineering Research Council of Canada (NSERC), and from Industrial Postgraduate scholarships to M. Hocking.


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Copyright information

© The Ecological Society of Japan 2009

Authors and Affiliations

  • Morgan D. Hocking
    • 1
    • 3
    Email author
  • Richard A. Ring
    • 1
    • 2
  • Thomas E. Reimchen
    • 1
  1. 1.Department of BiologyUniversity of VictoriaVictoriaCanada
  2. 2.Royal British Columbia MuseumVictoriaCanada
  3. 3.Department of Biological SciencesSimon Fraser UniversityBurnabyCanada

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