It's time to rethink how we classify species in marine ecosystems, say two University of Windsor ecologists in the University of Windsor's Great Lakes Institute for Environmental Research.
Nigel Hussey and Aaron Fisk, ecologists in the university's Great Lakes Institute for Environmental Research, are two co-authors on a new paper published in the journal Ecology Letters that challenges the standards used to assign various species numeric trophic positions within food webs. Trophic levels correspond to positions on a food chain. This means that producers always belong to the first trophic level and decomposers to the last trophic level, consumers that directly eat the producers belong to the second trophic level and so on. With a food web, food webs (or food cycle) depicts feeding connections (what-eats-what) in an ecological community.
To reach their alternative view, the ecologists examined information collected from such various marine organisms as sharks and manta rays from as far away as the Canadian Arctic and off the southeast coast of Africa.
Hussey and Fisk are of the view that their work has important implications for the ecology. Given that those numbers are used to develop population estimates by conservation managers who do everything from set fishing quotas to determining whether certain species should be listed as endangered or threatened.
Based on their findings they argue that it is time to reconsider the various standards used for fishing or assigning which species are actually endangered and which are not. The paper is titled "Rescaling the trophic structure of marine food webs."
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