Rapid adaptation to a new environment: is it reversible?
ArakiH2015.pdf (131.6Kb)Abstract
Accumulating evidence suggests rapid adaptation of fish populations when they are exposed to artificial hatchery environments. However, little is known if rapidly-adapted populations can readapt to their original, natural environment at the same rate. Here, I review recent studies on salmonid fish that address this issue. They indeed suggest rapid adaptation of hatchery populations, in which reproductive fitness under a natural environment became much lower than that in the wild population after only 1-2 generations of captive breeding. However, the reproductive fitness did not recover after one generation of natural rearing, implying that rapid adaptation to a new environment was not reversible at the same rate. I discuss potential consequences of the irreversible fitness reduction in extensively stocked fish species. Understanding the mechanism behind the irreversible rapid adaptation in fish populations will help us figure out a better, nature-friendly, and hence sustainable means of hatchery operations for human welfare.
Citation
Araki, H. (2015). Rapid adaptation to a new environment: is it reversible? In M. R. R. Romana-Eguia, F. D. Parado-Estepa, N. D. Salayo, & M. J. H. Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production of Aquatic Species: Proceedings of the International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA) (pp. 19-24). Tigbauan, Iloilo, Philippines: Aquaculture Dept., Southeast Asian Fisheries Development Center.
Publisher
Aquaculture Department, Southeast Asian Fisheries Development CenterSubject
Hatcheries; Adaptations; Breeding; Anadromous species; Behaviour; Stocks; Culture effects; Reproduction; Reproductive behaviour; Cultured organisms; Fish culture; Salmo trutta; Oncorhynchus gorbuscha; Oncorhynchus mykiss; Salmonidae; Oncorhynchus tshawytscha; Oncorhynchus kisutch; Fish stocking; Rapid adaptation; Reproductive fitness; Salmonid species
Type
Conference paperISBN
9789719931041Related items
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Role of growth hormone in the adaptation to sea water of juveline brown trout, (Salmo trutta)
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