October 2004 – LCRC update on Research Priorities in the
areas of Fishes & Fisheries
Priorities in 1999
contribution does walleye stocking make to the adult population?
Mackenzie - considerable progress evaluating the contribution of stocked
walleye to spawning populations in the Missisquoi and Winooski Rivers, and this
will continue in the future; planning to continue marking all fry and
fingerlings stocked into Lake Champlain
should we sample walleye?
Parrish - progress on sampling early life stages of walleye
smelt populations different among basins?
level of predation can smelt sustain in Lake Champlain?
lake trout naturally reproducing, and if not, why not?
Marsden - good evidence of successful lake trout reproduction in the Lake, but
recruitment still seems low. Questions
for future research - Is this due to low post-emergent survival, or
perhaps fish haven’t yet gotten large enough to show up in sampling gear.
Priorities in 2004 (for the next several years)
Top two priorities/themes were
Begin assessment and long-term monitoring
of fish populations/communities in Lake Champlain
and its major tributaries. LCRC should
seek new funding for establishment of a lake-wide fish community monitoring
program similar to the ongoing water quality/ plankton monitoring done by the
two states. This should include fish
species in the lake and those dependent upon lower reaches of large Lake
Champlain tributaries. This
latter group would include species that require these areas for spawning or
passage to upstream spawning areas (e.g. walleye, salmonids, sturgeon); and
also rare species that reside in these areas throughout their life (e.g.
eastern sand darters, channel darters, quillback, redhorses). Perhaps begin with Missisquoi
Bay and its tributaries, given the
many issues of current concern in that part of the Basin.
What is the status of alewife in Lake
Champlain, and what would be the effect of an alewife invasion on
the Lake Champlain ecosystem and the economy in the
basin? Part of this would be dependent
upon the previous priority listed – and it would be good to begin in Missisquoi
Bay, given the apparent finding of
alewife in the Bay in 2004.
Detailed investigations into the
food web structure of Missisquoi
Bay, to assess whether food web
interactions play a role in the severity, frequency, and species composition of
blue-green algae outbreaks. For example
– could decline in esocids due to disease, or impacts of white perch (an
invasive species) be related to algal blooms through a trophic cascade?
What affects lake trout
post-emergent survival, given that we have lots of successful reproduction. Or, is
recruitment beginning to occur and the fish are not yet old enough to show up
in assessment gear? What are the
impediments to restoration of this species?
Alternative methods for lamprey
control - particularly, can we use pheromones as a method for improving
trapping efficiency of spawning adults.
What is the status of sauger in
Populations of this smaller relative of the walleye have declined
dramatically, particularly in the southern part of the lake.
Investigate opportunities for
American eel restoration given that passage has been restored on the Richelieu
Interdisciplinary Research Opportunities
with Wildlife/Biodiversity, Middle Food Web/Exotics, Ecosystem Health, and
Toxics groups on a plan for extensive sampling/monitoring of species in
the lake, wetlands, and lower reaches of large tributaries – with particular
focus on those species about which know very little. Begin with Missisquoi
Bay and its tributaries, but
address other part of the lake in turn – this would have to be a
multi-year, long-term commitment.
with Middle Food Web/Exotics, Nutrients/Lower Food Web, and Ecosystem
Health groups on a plan to investigate the food web of Missisquoi
Bay to see if food web
dynamics or trophic cascades might be in some way linked to recent algal
blooms. (This could be the initial
phase of the previous point.)
with Land Use and Ecosystem Health groups on a plan to evaluate the
effects of land use on water quality, flow, and substrate composition of
large tributaries – and the effects of these factors on sensitive fish
species that rely on those tributaries.
Also relevant to Missisquoi
Bay and tributaries, as a
starting point, but expand to other parts of the basin.