Hatcheries Promise and Problems Upstream Ch' 3 5055, Ch' 12 Montgomery Ch' 8

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Hatcheries - Promise and Problems (Upstream Ch.
3 50-55, Ch. 12 Montgomery Ch. 8)

• Historical context the promise
• Problems with hatchery practices
• The technological fix
• Demographic risks
• Genetic evolutionary risks
• Other ecological problems
• III. Recommendations
• Guidelines
• Steps

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I. Historical context

• 1830s Used in Europe to study natural history
  (parr salmon? homing?)
• Mid-1800s Usurped to augment European stocks
  depleted by overfishing (without decreasing
  fishing pressure!)

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I. Historical context

• Hatchery successes in both Europe and North
  America fueled optimism that technology could
  overcome natural limitations.
• Successful returns typically occurred in rivers
  with otherwise good habitat.

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I. Historical context

• Optimism, followed by pessimism, followed by
  greater optimism
• Columbia River
• 1910 Poor returns even with massive hatchery
  output.
• 1914 Increased size of release in previous
  years, followed by record catch.
• By following the present system, there is no
  reason to doubtthat the annual pack in time can
  be built up to greater numbers than ever before
  known in hehistory of the industry.
• Oregon Fish and Game Commission, 1919 (as cited
  in Montgomery 2003)

But, no controls! Catches even in non-hatchery
streams were at record highs that year.
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I. Historical context

• Hatcheries closed in Alaska and B.C. in the
  1930s costs outweighed the benefits

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I. Historical context

• Reliance on hatcheries increased again with
  overfishing and increased habitat degradation
• - pollution
• - logging/sedimentation
• - dams
• - etc.
• Washington hatcheries
• 1896 - 4.5 million chinook fry 1950 28.9
  million 1968 92.7million
• No change in catch

Hatcheries often abandoned when habitat damage
prevented successful adult returns.
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I. Historical context

• Ultimately, most wild populations continued to
  decline, even where hatcheries were present.
• - Many runs are now gt70 hatchery fish (Box 12-1)
• Currently, 5 billion salmon fry released
  annually (40 Japan, 30 Alaska, 13 Russia, 8
  WOCI) (Augerot 2005)
• No consideration of stream or marine carrying
  capacity

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I. Historical Context

• Costs
• Oregon 15 million annually in 1990s
• Cost/fish 10-25/adult for most stocks,
  gt100/adult for some stocks!

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II. Hatchery problems

• The Technological fix
• A problem of attitude ? salmon without rivers.
• Habitat degradation allowed to proceed
• Easier to try to institute a technological fix
  than to change land use practices, face
  tradeoffs, curb societal desires.
• Lack of monitoring, rigorous evaluation of
  success ( of fish released, rather than numbers
  of returning adults).

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B. Demographic risks

• Fishing at exploitation rates set by hatchery
  stocks leads to depletion of wild populations.

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Differences in population productivity

• Fraser River sockeye
• Problem is differences in productivity (number of
  recruits/spawner/unit time)

SMSY? MSY? Exploitation rate?
Fig. 11-4
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C. Genetic evolutionary risks

• Brief overview of population genetics
• Genetic risks to salmon populations
• -

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C.1. Brief population genetics

• Natural selection
• Sexual selection
• Genetic drift
• Effective population size
• Genetic bottlenecks
• Inbreeding depression
• Trait linkages

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Genetic variation and sexual reproduction
Genes codes for a trait, found on a
chromosome. of chromosomes depends on species -
humans have 23, salmonids vary from 52 (pink
salmon) to 84 (brook trout). Ploidy - of
copies of each chromosome 2 (diploid) for most
sexually reproducing animals (one from each
parent) Alleles variations in the same
gene Genetic variation in population depends on
how the alleles for a given trait are passed down
through generations. Simplest case no selection,
random mating, well-mixed population, no new
mutations.
Campbell 2005
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Evolution is change in gene frequencies from
generation to generation
Could occur because of Natural selection
natural or artificial process by which breeders
are chosen from a population based on fitness or
phenotypic value. Genetic drift random changes
in allele frequencies due to sampling processes.
Campbell 2005
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What is fitness?What does it depend on?

• Fitness contribution to gene pool of subsequent
  generations.
• Depends on
• Survival
• Growth
• probability of mating
• number of progeny
• success of progeny
• In hatcheries human choice of key
  characteristics (size, growth rates, spawning
  times) ? Domestication

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Selection by

• Environmental conditions
• Disturbance regimes
• Competition
• Predation
• Disease
• Mate choice sexual selection

The most important selective pressures can differ
at different life history stages. So success of
hatchery fry in artificial environment doesnt
guarantee success in wild environment either as
juveniles or adults
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Linked traits

• Artificial selection for one trait (e.g., size)
  can lead to inadvertent selection for genes
  nearby on the chromosome.
• - For example, hip displasia in dogs

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Sexual Selection

• Intrasexual selection competition among members
  of the same sex.
• Intersexual selection
• mate choice (by females in salmon)
• Females have limited reproductive output
• Doesnt occur in hatcheries

Quinn 2005
Augerot 2005
Sockeye mating
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Genetic drift depends on population size
N total number of individuals Ne effective
population size. Typically smaller than
N. Hatcheries can reduce Ne substantially (e.g.,
Ne/N 0.1) skewed sex ratios, using milt from
several males on one females eggs (majority
fertilized by only one male) (http//www.glerl.noa
a.gov/seagrant/GLFLI/PublicNotebook/Curriculum/Pro
jects/GeneticGuidelines.pdf)
Campbell 2005
Population bottleneck
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Small population size

• Inbreeding depression greater probability for
  deleterious alleles to come together (homozygous)
• Can interact with linked traits

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C.2. Genetic risks to salmon populations

• Decreased genetic diversity
• i. Across populations no recognition of home
  stream concept in early U.S. hatcheries.
  Extensive transplantation of stocks across wide
  areas.
• ? Loss of local adaptation.
• ii. w/in population genetic diversity
• low Ne in hatcheries relative to wild
  populations
• - displacement of wild populations with
  hatchery populations.
• ? Loss of evolutionary potential within
  populations

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Loss of genetic diversity within populations
Hatchery
Wild
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b. Domestication change in selection pressures

• Due to
• non-random selection of brood-stock (e.g., run
  timing)
• Altered selection pressures
• - Hatchery practices (e.g., smolt sorting
  basing release on size)
• - Disruption of sexual selection anticipate
  effects on fitness, but sexual selection can be
  maladaptive too!
• - Hatchery conditions vs. wild conditions
  unclear for salmon, because dont spend entire
  life in hatchery.

Quinn 2005
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D. Other ecological risks

• Fish Behavior competitiveness, aggressiveness,
  displace native stocks, but with lower survival?
• Fish Health parasites diseases carried to
  wild populations (e.g., Gyrodactylus salaris in
  Norway, 1975 introduced from resistance Swedish
  salmon from the Baltic)
• Fish Physiology stress due to overcrowding,
  incomplete smoltification (lower fitness)
• Ecological context carrying capacity of streams
  and ocean, return of nutrients from ocean

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III. Recommendations

• Guidelines
• 1. Hatcheries for rehabilitation
• 2. Only one component of rehabilitation
• Need to deal with habitat (and hydro) issues
  simultaneously
• 3. Aim for genetic conservation in wild stocks
• Avoid artificial selection
• Need clear genetic guidelines for operation
• Avoid transplantation across watersheds

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III. Recommendations

• Guidelines
• 4. Mark all hatchery fish
• 5. Adaptive management ? adequate monitoring

Wild fish no adipose clip
Hatchery fish adipose clip
http//www.lrf.org/Env/Env-KokaneesFin.html
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B. Steps

• 1. Temporary Hatcheries
• Limited time while habitat restoration takes
  place
• Lower costs than permanent hatcheries
• Help re-establish severely depleted stocks
• Shorter duration of adverse ecological effects
• Extended only with explicit agreement
  acknowledging long-term costs

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2. Catch Augmentation

• Controversial, limited application
• e.g., Protecting tribal fishing rights
• Accounting for ecological effects
• clear marking of hatchery fish
• changes in fishing methods management
• selective fishing of hatchery fish
• reduced interactions between wild hatchery
• needs research

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3. Dismantle or revise methods where interfering
with rehab

• - e.g., good freshwater habitat

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Naylor et al. 2003

• Questions
• How are ecological effects of salmon farms
  similar to and different from those of
  hatcheries? How does this differ depending on the
  region (e.g., farms in PNW vs. Atlantic)?
• In what ways has economic globalization made
  environmental regulation of fish farms difficult?
• What are the pros and cons of different options
  (regulatory control, consumer labeling,
  international agreements) for encouraging reduced
  environmental impacts of fish farms? How might
  these approaches be used together?