--NEW Trout Stocking Program—(posted 03/05)

by Tim Clancy

 

The Knee Deep Club of Lake Hopatcong is pleased to announce a new exciting trout stocking plan for Lake Hopatcong.  Ironically the decision to drastically alter the club’s annual trout stockings is the direct result from the recent debate with the Division of Fish & Wildlife where the Division was recommending eliminating trout stocking at the lake by the state.

            The club, which has been in existence at the lake since 1946, is optimistic that by making these changes to their trout stockings they will be able to reestablish the holdover trout fishery that the lake was once famous for.   The 1,200 member club which has been stocking over $15,000 worth of trout each spring with their private money in the state’s largest public lake is launching the program this spring. 

The Division had recommended eliminating Lake Hopatcong along with six other larger lakes from their annual trout stockings.  After a major and successful lobbying effort by the club the state ultimately decided to continue stocking Lake Hopatcong, but in 2006 will stop stocking the other six lakes.  The state did decide to reduce the fish that Lake Hopatcong receives each year by 20% which amounts to about 2,000 less trout for the lake beginning in 2006.  The club is very disappointed in the state’s decision because the public was asked to weigh in on the issue, whether to continue or eliminate trout stocking at the lake, and the public overwhelmingly supported continued stocking at the lake.  There was never any recommendation, or discussion of a reduction of trout for the lake presented to the public.  The club feels that the reduction of trout at the lake is an unjustified action taken by the Division because the club did such a good in contesting some of the evidence presented by the Division.

            The club presented evidence of holdover trout at the lake and improving water quality as the result of over $100 million invested at the lake on water quality initiatives by the lake community.  They showed that eliminating spring trout stocking at the lake would have a detrimental impact on the local economy and the Division’s own finances from losses of future license and trout stamps sales.  But it was the research that the club did to justify future stockings that led to a clearer understanding of what led to the dramatic decline in holdover trout that was witnessed at the lake in the mid 1980’s.  Prior to that hundreds of large holdover trout were caught at the lake each year.  Then suddenly they dropped off to just dozens or even handfuls reported each year.

            Like many others the Knee Deep Club thought this sudden decline was the direct result of declining water quality because of the environmental impact from the changes that had occurred in the watershed.  But still every year several holdover trout were caught.  The club cannot verify every holdover caught, which are relatively easily to identify because the distinct colorings of the brown trout when stocked change to silver once they live in the lake for a year and feed on the natural forage of herring.  However when significantly large trout in the 6-10 pound range were weighed in they were easily identified as holdovers.  Also any trout caught through the ice would represent holdovers, like the several that were verified this year.  Also for public relations purposes the club often tagged their fish and every year trout bearing previous years’ tags were caught.

            Yet the Division’s biologists insisted that their studies showed that the lake no longer had habitat that would support trout year round.  As a matter of fact they used that position to justify the reduction in trout for the lake when the decided to change the lake’s classification from trout maintenance to non-trout.   But every year the scientist that do water quality monitoring for the Lake Hopatcong Commission verify suitable summer brown trout habitat exists. That contradiction led the club, through extensive research, to the determination that the decline of holdover trout at the lake was more the result of the state’s changes to it’s own stocking policies that were in effect from 1960-1983 than from any decline water quality.  During that period the state had developed stocking policies at Lake Hopatcong based on six years of studies conducted under the leadership of former Fisheries Biologist Dick Gross between 1953 and 1959.  The studies conducted then were absolutely extraordinary in that in cooperation with the Knee Deep Club trout were tagged and stocked and data collected over several years.  After analyzing all the data it was determined that Lake Hopatcong should be stocked with primarily brown trout, that they should be stocked early in the year and that they must be a minimum of at least 11” to survive year round in the lake.  Any of the fish that were stocked outside of those guide lines rarely held over. 

            These policies were determined after reviewing data showing which fish stocked resulted in the highest numbers of holdover trout.  And they made sense in that it was understood that brown trout were the most tolerant of the warmer temperatures that occur in marginal trout lakes like Hopatcong.  Stocking early made sense because it gave these hatchery-reared fish more time to acclimate to a wild environment and learn to feed on the native forage.  And it was felt that the larger, 11 inch plus trout, did better holding over because they could avoid being eaten by the other large predators in the lake and being larger were better able to take advantage of the lake’s primary forage, herring.

            That policy is what the club will return to with its own stocking beginning this spring.  But what Dick Gross’s studies proved back in the fifties is further backed up by modern studies and literature published on brown trout.  The biggest disagreement that the club has with the Division on the issue of suitable trout habitat is the temperatures that trout, and specifically brown trout, can tolerate.  They claim that trout cannot survive above 21 degrees C. (69.8 F.) yet we could not find that in any of the literature we reviewed.  Every expert in the world we could find info from said brown trout could live in temperature of a minimum of 24 C. (75.2 F.) and some suggest even higher temperatures.  The E.P.A. uses 26 C..  But after reading “Quantitative Ecology and the Brown Trout” by. Dr. J.M. Elliot of Oxford University it became clear that there is a lot more involved in understanding temperature tolerances of trout than simply the temperature. We were first led down this path and to Elliot’s book by Dr. Robert Benke Professor Emeritus from Colorado State University who is one of the most renowned experts on trout in the world.  As Dr. Behnke explained and then we confirmed in Elliot’s book temperature in and of themselves are generally not lethal to trout unless they go over 80 F.  There are other important factors that come into play, mainly the duration of the higher temperatures and then the general health of the fish.  Specifically do the fish have adequate energy reserves to withstand less than ideal condition?  Ideally brown trout thrive in temperatures less 68 F. (let’s just stay with Fahrenheit for now on). That is the perfect world for brown trout and they will experience maximum growth in that zone.  Above those temperature they will continue to feed and act like trout but may burn more energy then they are able to consume and may actually lose weight.  They will continue feeding right up to 77 F.  But if exposed to those higher temperatures for too long they could eventually die. Trout could not live in a lake that had temperatures that high all year long, because they’d have to depend on their energy reserves which would run out over time.  But if they are forced out of that ideal temperature zone for a short duration but have good energy reserves (body mass) they will bounce back and start putting on weight once the optimal conditions return.  At Lake Hopatcong every year for about 4-6 weeks in July and August trout are forced into a zone of water of between 72-74 F.   If the fish are well nourished with good energy reserves this presents no problem because they will continue to feed and burn some fat, but once the lake turns over in Sept. they have ideal conditions throughout the entire water column and will bounce right back.  This is just part of the life cycle of trout in what are considered marginal lakes.  But if the fish are small and poorly nourished they are more likely to succumb in these less then ideal conditions because they’ll have insufficient reserves to sustain themselves.

            From 1960-1983 the stocking policies of the Division involved stocking the proper species, at the right time of year and of adequate size to survive in the lake.  Over time they have gotten away from all three of these practices.  We don’t know when they changed from stocking the trout early but under the direction of Dick Gross they were to be stocked no later then April.  And remember we’re talking only brown trout here.  Well for quite awhile, we don’t know for certain but we think in 1983 when the Pequest Hatchery came on line, they started stocking all of their brown trout the last week in May.  So these fish had little time to acclimate to a wild environment and fatten up for the summer crunch when they would need energy reserves to survive.  Also when the Pequest came on line they stopped stocking 11 inch plus fish and the browns that they stocked late in May averaged about 9 inches.  Dick Gross’s studies showed that these smaller fish never held over.  It wasn’t just the predation by the other fish or being too small to eat the lake’s herring alone but the fact that they had no built in energy reserves to survive the summer weeks when they were forced into 72+ F. water.  Finally in 1995 the Division changed from stocking at least 50% brown trout to only 25% and increased the brook trout to 50% and they are least tolerant of the conditions at the lake and will never hold over.

            The only trout that were likely to hold over after 1883 were those stocked by the Knee Deep Club because all of our fish met the size requirement.  But we didn’t understand the science then and we split our stocking into one preseason and one  in May.  So only 1/2 of our fish were going in early enough to meet the requirements established by Dick Gross.  And those fish, because we didn’t know any better were split up, between the different species with many brook, rainbow and tiger trout being stocked during the first stocking.  So if we were stocking 1,000 trout preseason only 250 of our fish were ideally suited to holdover.  Our May stockings included 40% browns but we don’t know if these fish would have as much success holding over as the earlier stocked fish.  Then you have to factor in losses like how many fish were caught and kept, died from hook mortality and went over the dam during high water conditions, which are prevalent during the spring.  So we were basically down to dozens of fish that were ideally suited to hold over.  And also it’s only been in the last ten years or so that the club has had the resources to stock those kinds of numbers of fish.  We remember back in the early 1990’s we were lucky to have enough money to purchase 1,000 trout each year.   1999-2001 records showed we stocked 2,000 each year and the last two years we stocked 2,800 trout.  But remember only 12.5% of those fish were ideally suited to hold over and the Division’s fish didn’t stand a chance.  So even in the best of years since 1983 only around 350 trout were being stocked that were ideally suited to holdover.  And in a 2,650-acre lake that’s not a lot of fish, especially after anticipated losses.

            So now we have completely adjusted our own stocking to follow the guide lines set up by Dick Gross in 1960 and are excited because we feel that in short order we will see dramatic improvement in the lake’s holdover trout fishery.  First we are increasing our overall stocking by 1,000.  We were able to accomplish that at no additional cost by down sizing what we call our production fish by one inch and applying the monies saved to purchase an additional 1,000 11-12 inch fish.  So instead of purchasing 2,600 13-15 inch fish, we will be changing to 2,600 12-14 inch fish, still all respectable size fish.  Also we will be stocking 80% of our production fish preseason.  They will break down as follows: 1,000 brown trout 11-12, 1,000 70% browns & 30% rainbows 12-13 and 1,000 13-14 with a 70%/30% split.  We will also stock 100 trophy trout between 16-21 inches and they will include all species.  That first stocking will occur April 3 one week prior to the season opener.  Rainbows were included because they are known to be tolerant of warmer temperatures and are seen to hold over every year.  Plus brown trout don’t go on a heavy feed until the water warms up to about 55 F. and we want the public to enjoy early season angling success and the rainbows will bite earlier.  The state’s first stocking of the year is exclusively brook trout so we feel that thee will be good early season angling.

            Our second socking of the year, which is primarily done to promote our Annual Trout Contest, will occur on may 7 one week prior to our contest and will consist of 600 trout 12-14 inches with a 70%-30% split of brown and rainbows.  And also another 100 trophies between 16 & 21 inches.

            We're very excited and optimistic about this new program and we feel that the science and the history of trout stocking at the lake backs us up.  But on the outside chance that we are wrong and it is determined that Lake Hopatcong is ultimately a put and take trout fishery with very few holdovers like more than 90% of the waters stocked by the state this will still be a good program.  While we don’t agree with all the results of the tagging study conducted by the state because it was too small of a sampling, some things that came out of it were accurate.  It showed that those fish stocked earliest and brown trout had the best overall returns.  So on the outside chance that this doesn’t play out like we hope, we will see much better angler success by stocking early and mainly browns.

            All of our fish that we are stocking for potential holdovers we are marking with dorsal fin tags and we ask the public to help us by releasing those trout this year so we can measure our success.  The state fish which will number over 10,000 this year and our non-trophy fish will not be tagged so there will be plenty of fish to keep for those who enjoy eating them. But PLEASE release all tagged trout this first year and leave the tags in place.  And remember between our fish and Fish & Wildlife’s there will be more than 5,700 trout stocked for the season opener, which are more trout stocked in the lake for Opening Day than in the history of the lake.  So come on up and enjoy the best trout fishing in the state this year.  Boat Rentals are available at Dow’s Boat Rental (973) 663-3826 and Lakes End Marina (973) 398-5707.  And if things go as we plan we’ll be seeing another Knee Deep success story.  You just can’t keep a good club down.