one publication added to basket [61735] | Changes in the spatial structure of Grand Bank yellowtail flounder: testing MacCall's basin hypothesis
In: Journal of Sea Research. Elsevier/Netherlands Institute for Sea Research: Amsterdam; Den Burg. ISSN 1385-1101; e-ISSN 1873-1414, more Also appears in:Geffen, A.J.; Nash, R.D.M.; van der Veer, H.W. (Ed.) (2004). Proceedings of the Fifth International Symposium on Flatfish Ecology, Part II. Port Erin, Isle of Man, 3-7 November 2002. Journal of Sea Research, 51(3-4). Elsevier: Amsterdam. 167-338 pp., more | |
Keywords | Aquatic organisms > Marine organisms > Fish > Marine fish Distribution > Geographical distribution Range Spatial variations Limanda ferruginea (Storer, 1839) [WoRMS] ANW, Grand Banks [Marine Regions] Marine/Coastal | Author keywords | yellowtail flounder; flatfish; MacCall; basin; range; Grand Bank |
Abstract | MacCall's basin model postulates that the geographic range of marine fish will co-vary with population density as a function of habitat selection. Therefore the geographic range of a stock will increase with increasing abundance, while the opposite is true of declining stocks. In this paper we investigated range contraction, and expansion, in the distribution of yellowtail flounder on the Grand Banks in relation to sediment type, temperature and depth. Yellowtail flounder were mainly distributed on gravely sand, sand-shell hash, rock-sandy sediments an to a lesser extent on rocky bottoms. As well, yellowtail flounder are highly associated with shallow, warmer waters more frequently than expected based on its occurrence in the environment. Employing a generalised additive model (GAM), we modelled the spatial distribution of yellowtail flounder in association with the environmental variables. The GAM provided a reasonable fit to the spatial distribution of yellowtail (58% overall). During periods of lower abundance, the fit of the spatial model increased, demonstrating the importance of depth and temperature in influencing the distribution of this species. We concluded that the observed range contraction of yellowtail flounder at low population levels represents selection for preferred habitats, whereas during periods of stock increase, the range of yellowtail flounder expands into less favourable habitats in support of MacCall's basin hypothesis. |
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