'Whales eat fish'? Demystifying the myth in the Caribbean marine ecosystem

Lyne Morissette, Kristin Kaschner, Leah Gerber

Research output: Contribution to journalArticle

11 Scopus citations

Abstract

There has been much recent discussion about the idea that large whales are potential competitors with fisheries for available marine resources. Based on this idea, often referred to as the 'whales eat fish' conflict, culling whales has been proposed as a way to increase resources available for human consumption and thereby ensuring global food security. However, the scientific basis for such arguments remains unclear, especially in the Caribbean waters where baleen whales generally do not feed. In this article, we (i) develop an ecosystem model describing the trophic interactions between whales, fish and fisheries in the Caribbean waters, (ii) calculate the level of overlap between cetaceans and fisheries for food resources, and (iii) simulate the removal of cetaceans from the Caribbean waters in order to quantify the potential increase in available biomass of commercially important fish. Ten groups of cetaceans are considered in the model, including baleen whales, toothed whales and small cetaceans. Our results suggest that baleen whales are not a threat to fisheries in Caribbean waters, while toothed cetaceans seem to be more impacted by fisheries than they actually impacting them. Whales target different types of food resources and consume significantly less than what is taken by fisheries. Moreover, simulated reductions in large whale abundance do not produce any appreciable increase in biomass of the commercially important fish species. In some cases, the presence of some whales actually improves fishery yield as a result of indirect predation effects.

Original languageEnglish (US)
Pages (from-to)388-404
Number of pages17
JournalFish and Fisheries
Volume11
Issue number4
DOIs
StatePublished - Dec 1 2010

    Fingerprint

Keywords

  • Cetacean ecology
  • Ecosystem modelling
  • Fisheries management
  • Marine mammal-fisheries interactions
  • Trophic impacts
  • Whaling

ASJC Scopus subject areas

  • Oceanography
  • Ecology, Evolution, Behavior and Systematics
  • Aquatic Science
  • Management, Monitoring, Policy and Law

Cite this