Like many areas in the Pacific Northwest, British Columbia has less than 70 described species of indigenous freshwater fish, but recent concerns have been raised because the "species" level of classification only captures a small proportion of diversity. In conjunction with Dr. Eric Taylor’s lab (UBC) and Eric Parkinson from the B.C. Ministry of Fisheries, we have undertaken to study a polytypic freshwater fish, the rainbow trout. Rainbow trout are good model candidates for such a study because they live in a variety of aquatic habitats and adopt life histories that range from large-bodied anadromous forms to small dwarf populations isolated above waterfalls. Despite the fact that biologists have known about this variation in life-history tactics for some time, little is known as to whether these differences represent evolutionarily significant units or whether all populations are part of a highly plastic but single species. During 1998 to 2000 we undertook a wide geographic survey of B.C. rainbow trout, sampling replicate populations that we hypothesized might be different from one another because of differences in rainbow trout trophic ecology. In addition, we have also conducted common-rearing experiments to determine whether any morphological differences in wild rainbow trout forms represent genetically inherited traits. We have found evidence to suggest that morphological differences in rainbow trout ecotypes have a genetic basis and are not environmentally induced. Eventually we will use a geographic information system (GIS) and a relational watershed database to determine the frequency of rainbow trout forms based on the frequency of different ecological conditions across the Province. This project will help managers determine which forms of rainbow trout are most at risk.

Main Goals of our project:

 Development a morphometric discriminant function for rainbow trout ecotypes

 Develop rules for determining the frequency of rainbow trout ecotypes across British Columbia.

 Determine whether morphological differences among rainbow trout ecotypes have a genetic basis.

Examples of rainbow trout ecotypes:

Piscivorous rainbow trout appear to have evolved as specialized predators on non-anadromous sockeye salmon (kokanee)

Another well-known rainbow trout form is the anadromous rainbow, commonly referred to as steelhead trout.

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