Bait consumption by marine predators peaks at midlatitudes around the globe and is driven to a greater extent by predator type than by water temperature, a study finds. The geographic distribution of primary production and fishing is well documented, but a global map that links consumption within food webs to temperature and other ecological drivers is lacking. Matthew Whalen, J. Emmett Duffy, and colleagues deployed squid bait, which attracts many generalist marine predators such as fishes and crustaceans, at 42 shallow coastal sites spanning 105 degrees of latitude across four continents and multiple ocean basins. The authors found that feeding intensity declined near the equator in both hemispheres, both in seagrass and sediment habitats. Bait consumption was more strongly predicted by the taxonomic composition of the predator community than by water temperature, predator density, biomass, or species diversity. Additional analysis suggested that the effect of temperature on the rate of bait consumption is indirect. According to the authors, understanding consumption by midlevel predators is key to coastal conservation and restoration efforts. Moreover, the results suggest that changes in the composition and geographic ranges of predator communities in the world's oceans may have wide-ranging repercussions for marine ecosystems.
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Article #20-05255: "Climate drives the geography of marine consumption by changing predator communities," by Matthew Whalen et al.
MEDIA CONTACTS: Matthew Whalen, University of British Columbia, Vancouver, CANADA; tel: 703-909-5732; e-mail: < mawhal@gmail.com >; J. Emmett Duffy, Smithsonian Institution, Edgewater, MD; tel: 202-633-4037; e-mail: < DuffyE@si.edu >
Proceedings of the National Academy of Sciences