Location
UMass Amherst
Start Date
28-6-2011 10:20 AM
End Date
28-6-2011 10:40 AM
Description
Migration is a spectacular example of biocomplexity, and migratory species are frequently important ecological, cultural and economic components of ecosystems. Migration differs among populations and can be described by differences in migratory systems. An important component of the migratory system is the migration syndrome the set of phenotypic and behavioral traits that are expressed by individual organisms during migration events. Here, I present a conceptual framework of migration syndromes in diadromous fishes and use three case examples from the Columbia River that illustrate how differences in migration syndromes may dramatically affect interpretations of “success” during upstream migrations of adults. The scientific paradigm for the study of fish migration has been strongly influenced by salmonids studies, and a key feature of anadromous salmonid migration is strong natal homing. High site fidelity is associated with local adaptation and genetic structuring on fine scales (as small as l0s of m). American shad appear to home at the scale of river basin, suggesting a lower degree of site fidelity and population structure at moderate scales (10-100s of km). In contrast, current evidence suggests little or no site fidelity to natal drainage during upstream migration by Pacific lamprey. Population genetic structure is relatively weak and only evident at scales of 103 km. These differences in site fidelity result from differences in breeding site selection behaviors, and these differences presumably also influence behavioral decisions during passage of local scale obstacles (waterfalls and fishways). For example, a “failed” passage attempt in a taxon with strong homing accurately represents an unsuccessful passage event, whereas the same outcome in a taxon with low natal site fidelity may actually reflect adaptive behavior in a species with a flexible breeding site selection program. Consequently, construction of passage metrics and standards should explicitly consider the underlying migration syndrome of the target species.
Session B4- Migration syndromes and passage “success” in diadromous fishes
UMass Amherst
Migration is a spectacular example of biocomplexity, and migratory species are frequently important ecological, cultural and economic components of ecosystems. Migration differs among populations and can be described by differences in migratory systems. An important component of the migratory system is the migration syndrome the set of phenotypic and behavioral traits that are expressed by individual organisms during migration events. Here, I present a conceptual framework of migration syndromes in diadromous fishes and use three case examples from the Columbia River that illustrate how differences in migration syndromes may dramatically affect interpretations of “success” during upstream migrations of adults. The scientific paradigm for the study of fish migration has been strongly influenced by salmonids studies, and a key feature of anadromous salmonid migration is strong natal homing. High site fidelity is associated with local adaptation and genetic structuring on fine scales (as small as l0s of m). American shad appear to home at the scale of river basin, suggesting a lower degree of site fidelity and population structure at moderate scales (10-100s of km). In contrast, current evidence suggests little or no site fidelity to natal drainage during upstream migration by Pacific lamprey. Population genetic structure is relatively weak and only evident at scales of 103 km. These differences in site fidelity result from differences in breeding site selection behaviors, and these differences presumably also influence behavioral decisions during passage of local scale obstacles (waterfalls and fishways). For example, a “failed” passage attempt in a taxon with strong homing accurately represents an unsuccessful passage event, whereas the same outcome in a taxon with low natal site fidelity may actually reflect adaptive behavior in a species with a flexible breeding site selection program. Consequently, construction of passage metrics and standards should explicitly consider the underlying migration syndrome of the target species.
Comments
Chris CaudiII is a Research Assistant Professor in the Department of Fish and Wildlife Resources at the University of Idaho. His broad interests are in the ecology and evolution of animal movement and the conservation of aquatic resources. He holds a MS from the University of New Hampshire (1995) and Ph.D. from Cornell University (2002). He conducted postdoctoral research at Georgia Tech before joining the Fish Ecology Research Lab at the University of Idaho in 2003 for a second post-doc. He has directed the FERL program since 2008, largely focusing on large scale telemetry studies of adult salmon, Pacific lamprey, and American shad in the Columbia, Snake, and Willamette Rivers.