Stocking Fish to Suppress Illegally Introduced Fish to Protect Legally Introduced Fish...
“While whitefish are struggling in Maine, I do not feel that it warrants moving them around at the expense of wild, native fish.”
Maine Department of Inland Fisheries and Wildlife recently approved a proposal to stock lake trout on top of wild native lake trout and brook trout in Haymock lake to try to reduce nonnative smelt that are stressing a state-introduced lake whitefish population.
The Maine chapter of NFC formally opposed the proposal. While several conservation groups in the state shared an article written by NFC Executive Director Bob Mallard challenging the proposal, unfortunately, the only group in the state to formally oppose it was NFC.
“Stocking lake trout on top of wild native lake trout to try to control nonnative smelt to protect nonnative whitefish doesn’t make sense.”
This proposal highlights everything wrong with fisheries management today. Had the state not moved whitefish around to try to save them under what is called “wild refuges,” we would not be talking about stocking lake trout on top of wild native lake trout and brook trout in a water that has not been stocked in 20 years.
The lake trout in Haymock Lake are not "under-performing," they are doing exactly what lake trout should be doing in what is acknowledged by IFW to be “mediocre lake trout habitat.” With depth, temperature, and dissolved oxygen all noted as bottlenecks, what makes us think that the stocked lake trout will fare any better than the wild ones?
NFC is one of the only organizations that has spoken up in regard to wild refuges, advising utmost caution and concerns in regard to how, where and when they would be used. Our position resulted in one defection from the board, as well as a suggestion from a peer organization that we get fully on board with this risky management tool.
“This is why wild refuges scare me. Where does it end and who decides what goes where, when and why?”
The Haymock Lake proposal places a higher value on nonnative whitefish than it does wild native lake trout and brook trout. It takes a water out of consideration for State Heritage Fish designation just 5 years short of when it would become eligible under the “not stocked in 25 years” clause. And the proposal attempts to address an illegal nonnative fish introduction by moving more fish around.
“Stocking lake trout on top of wild native lake trout to try to control nonnative smelt to protect nonnative whitefish doesn’t make sense.”
When IFW announced that the proposal was approved, Mallard submitted a request to obtain the internal peer review documents. Out of 13 submissions, roughly half mentioned concerns with regard to the proposal, the most damning of which stated:
I would be concerned that the stocking of lake trout might also affect the whitefish population due to increased predation.
I’m not convinced that LKT [lake trout] predation will not then become a problem for the remaining whitefish.
I have concerns about using hatchery LKT [lake trout] for this project. From what I know, the original and likely native LKT pop was never extirpated… It is possible that the native LKT stock and genetic signature is still there… I just raise this concern because LKT (native pops) are also an SGCN [Species of Greatest Conservation Need] species and I don’t think we want to potentially compromise one SGCN for another… maybe especially in a situation where we know the LWF pop is not native to this water…
There were a number of mentions of using triploid lake trout, nad-zapped sterile fish, as an alternative to standard hatchery fish. One concern would be that these fish grow faster and larger than their fertile cousins and could increase predation on whitefish as well as smelt. Currently, Maine does not raise triploids in its hatchery system. If this idea takes hold, these fish could find their way into the recreational fishing stocking program as hybrid splake have. In fact, one submission suggested they try splake.
Its worth pointing out that this would be a fantastic use of triploid fish, and if this is successful, the availability of triploid fish could hopefully open this type of biological control up to other areas.
…the use of triploids or splake should be thoroughly explored and considered
…this proposal would be a good candidate for a triploid stocking program if we had one
In 2 cases, peer review submissions misrepresented the impact on State Heritage Fish waters. Haymock Lake is just 5 years away from SHF designation, stocking lake trout would knock it back to 25 years. One peer review author spoke as if the proposal would not affect the looming SHF designation, which is untrue as it would derail it for 25 years:
There are no conflicts with Heritage waters in the drainage.
…but I think triploids would be an added consideration to the wild fisheries in Haymock especially as it approaches its heritage listing status.
Stocking lake trout over wild native lake trout and brook trout to suppress illegally introduced nonnative smelt to save legally introduced nonnative lake whitefish is a tough proposal to embrace. If we truly want to discourage illegal nonnative fish introductions we need to lead by example and walk the walk not just talk the talk…