A major uncertainty associated with hatchery reform and the
conservation of naturally spawning populations is the causes and
consequences (both ecological and genetic) of straying between
populations of salmon (both hatchery and wild). To appropriately
manage salmon populations it is important to understand how hatchery
and management practices (e.g. habitat alterations, transport,
hatchery rearing and release procedures) will affect olfactory
imprinting and ultimately homing and straying. Homing is governed by
the olfactory discrimination of home-stream water and exposure to the
home stream during appropriate juvenile stages is critical for
olfactory imprinting and successful completion of the adult homing
migration. Currently, there is no effective way to anticipate how
different management practices will affect homing because there is no
assay for whether salmon have imprinted to a particular site(s)
(beyond monitoring adult return patterns). We have previously
demonstrated that olfactory receptor neurons are sensitized to
home-stream odors during the process of imprinting and the goal of
this project is to exploit this sensitization to develop and validate
new molecular tools for assessing imprinting. We are using cDNA arrays,
real-time PCR and in situ hybridization to determine whether sensory
neuronal populations in salmon change predictably during the process
of imprinting. Ultimately these tools will used to identify the
critical developmental periods and environmental conditions required
for olfactory imprinting in Pacific salmon.
Principal Investigator
Andrew Dittman (Resource Enhancement Utilization Technology Division)
Collaborators
Darran May; School of Aquatic and Fishery Science, University of Washington
Robert Lane; Assistant Professor, Wesleyan University
Barbara Trask; Fred Hutchinson Cancer Research Center
Leroy Hood; Institute for Systems Biology
