This research is supported by JST PRESTO program, Asahi Glass Foundation, Grant-in-Aid for Young Scientist (B) (22770075) and Grant-in-Aid for Scientific Research on Innovative Areas (23113007 and 23113001) from the Ministry of Education, Science, Sports, and Culture to J. K. and NIG Collaborative Research Program (2011-A68, A69). A. I. is a fellow of the Japan Society of Promotion of Science.
Shifts in morphology and diet of non-native sticklebacks introduced into Japanese crater lakes
Article first published online: 27 APR 2012
© 2011 The Authors. MicrobiologyOpen published by Blackwell Publishing Ltd.
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Ecology and Evolution
Volume 2, Issue 6, pages 1083–1098, June 2012
How to Cite
Adachi, T., Ishikawa, A., Mori, S., Makino, W., Kume, M., Kawata, M. and Kitano, J. (2012), Shifts in morphology and diet of non-native sticklebacks introduced into Japanese crater lakes. Ecology and Evolution, 2: 1083–1098. doi: 10.1002/ece3.234
- Issue published online: 12 JUN 2012
- Article first published online: 27 APR 2012
- Received: 19 January 2012; Revised: 9 February 2012; Accepted: 13 February 2012
- contemporary evolution;
- rapid evolution
An increasing number of exotic animals are causing ecological problems. Therefore, for better ecosystem management, it is important to understand how exotic species colonize and adapt to novel environments. The threespine sticklebacks (Gasterosteus aculeatus) can be a good vertebrate model system to explore the ecological and genetic mechanisms of adaptation not only in natural populations, but also in non-native populations. Although morphological changes have been documented in several introduced populations of stickleback, little is known about the dietary changes during colonization into novel environments. Here, we investigated the morphological and dietary changes of exotic threespine stickleback populations introduced into three Japanese crater lakes (Lake Towada, Lake Kussharo, and Lake Shikotsu). Sticklebacks were introduced into the crater lakes likely along with salmonids transplanted for aquaculture. The stickleback population in Lake Kussharo had multiple mitochondrial haplotypes and had larger phenotypic variances than other crater lake stickleback populations that had only one mitochondrial haplotype. Compilation of historical data on the morphology and stomach contents of the Lake Towada stickleback population showed that substantial shifts in body size and stomach contents occurred after colonization. Some of these changes may be related to an outbreak of the Schistocephalus parasite. These results suggest that sticklebacks can change their morphology and trophic ecology when they colonize novel environments. Therefore, extreme care should be taken when salmonids are transported between watersheds for aquaculture and that long-term monitoring of exotic species is essential for ecosystem management. In addition, further genetic studies on phenotypic changes in crater lake sticklebacks would help elucidate the genetic mechanisms underlying the adaptation of exotic fishes to novel environments.