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Points of concern in
Sea Duck conservation |
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COMPENSATORY VS ADDITIVE
HARVEST
- The management for sustainability of the
unique tribe of Mergini is based on empirical considerations of
population status and harvest using r-strategists such as mallards as a
model.
- Management and recovery plans for
seaducks of K-selected strategy are frequently extrapolated from species
with r-selected strategy.
- Overexploitation of sea ducks may occur
using present compensatory mortality models instead of realizing unique
life stage history strategies for each species.
- Seaduck unique life history promotes a
lower threshold mortality rate. Sustainable harvest rates for seaducks
are much lower than for other waterfowl.
Declines indicate that this lower threshold point is being reached so
Mergini species have less capacity to compensate for any additional form
of mortality such as hunting.
Relatively small increments in overall adult mortality, due to additive
effects of hunting, may not be sustainable by some species.
We do not have a comprehensive theory of exploitation based on
ecological principles as a basis for sea duck management disciplines.
- It is scientifically rash to continue a
liberal bag limit in light of the reported declines. The threshold point
has been exceeded so mortality is additive. Excessive winter harvest
measures could be impairing sustainability.
- Adult female sea ducks the critical
segments of sea duck populations are left out of the management
equation.
- When the general bag limit is reduced it
is shown that hunters resort to higher limits of sea ducks to fill their
bag. On the East coast up to 80% of their possession were sea ducks.
- Over exploitation of sea ducks on their
wintering grounds may occur using present compensatory mortality models
of species with distinctly different life stage histories
- Overexploitation of the unique Mergini
tribe may occur using present dabbler duck compensatory mortality models
instead of developing life stage history strategy for each species or at
least differentiating tribes.
- Increases in sport harvest of seaducks
has been noted. Increases in subsistence harvest of seaducks has been
noted.
- An increase in trophy hunting for sea
ducks was reported at Kodiak.
- A dramatic shift in harvest from
dabbling ducks to sea ducks has occurred on the Atlantic Coast due to
dabbler harvest restrictions. The sea duck component of the sport
harvest has reached 80% in some recent years.
- As certain seaduck species have been
restricted the remaining species take on the additional pressure, which
presents a domino effect from one species to the next.
- The Seaducks must be managed as a
complete tribe, not piece meal as is presently condoned.
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[ Home ] [ Reproductive Strategies ] [ Fidelity to Areas ] [ Compensatory Vs Additive Harvest ] [ Bag Limits ] [ Biological Considerations ] [ Cumulative Mortality Factors ] [ The Status of Seaducks ] [ A Time for Action ] [ Population Table ] [ Population Graphs ] [ Daily News Article ]
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