2013 State of the Eastern Finger Lakes
On March 18 and 20, 2013 two public meetings were held to discuss the State of the Eastern Finger Lakes, specifically the fisheries of Cayuga, Owasco, Skaneateles and Otisco Lakes. The first meeting took place at Bass Pro Shops in Auburn NY, and the second took place at Groton High School, Groton NY. During these meetings five presentations were given, one on basic Limnology and a general overview of fisheries management actions and one for each of the four lakes on their fisheries and current management activities. Following the presentations, there was a question and answer period. The following information is a brief selective summary of some of the key points of the presentations for those who were not able to attend or as review for those who did.
Limnology and Fisheries Management Actions
- The Finger Lakes are highly diverse from a fisheries standpoint due to different characteristics such as basin morphology, watershed size and land use within watersheds.
- Some important facts about water:
- water is slow to warm up and to cool down,
- temperature induced differences in density produce a resistance to mixing,
- water is most dense at 39° Fahrenheit (or 4°C),
- ice is less dense than water (i.e., it floats),
- cold water can hold more oxygen than warm water.
- During summer, thermal stratification develops with three distinct layers:
- A warm surface water layer called the epilimnion, which is subject to mixing from wind.
- A zone of rapid temperature change (≥1° Celsius/meter) called the metalimnion; the "thermocline" is the point at which temperature change is the fastest.
- The deep cold water layer is called the hypolimnion.
- Fall turnover takes place when surface water cools and sinks until the entire waterbody is the same temperature/density. Wind action causes the entire water column to mix top to bottom, which is an important step in nutrient cycles and replenishes dissolved oxygen.
- During winter some lakes freeze over and some don't. For example, Cayuga has too much mass to lose enough heat to freeze over in the vast majority of winters, while Otisco always freezes over. In all cases the warmest water (39° F) occupies the deepest portions of the lake.
- For lakes that freeze over, there is another "turnover" prior to the onset of summer stratification, called spring turnover. Warming of the surface layer eventually creates the resistance to mixing and sets the stage for summer stratification.
- Oligotrophic lakes are deep, cold, and relatively low in nutrients with a well oxygenated hypolimnion during summer stratification. Good examples are Cayuga and Skaneateles lakes.
- Mesotrophic lakes are higher in nutrients, relatively more productive, and the hypolimnion remains oxygenated during summer stratification. Owasco Lake is a good example of a Mesotrophic lake.
- Eutrophic lakes have high nutrient loading and are extremely productive with an anoxic (void of dissolved oxygen) hypolimnion during summer stratification.
Fisheries Management Actions
- Some important fisheries management activates are fish stocking, using gill nets and electrofishing gear to sample fisheries, sea lamprey control, habitat protection and enhancement and establishing fishing regulations.
- The Angler Diary Cooperator program on the Finger Lakes is another very useful management tool. Diaries provide species compositions of angler catches and catch rates (fish/hour of angling effort).
- If you're not a cooperator please sign up today!
- Access to the resource is provided with boat launches, shore fishing access sites and public fishing rights on tributaries.
- Provide information such as places to go fishing, fish stocking lists, biologist reports and a fishing hotline. This and much more information on fishing can be found on the NYSDEC Website.
- There are no alewives or rainbow smelt in Skaneateles Lake. The main forage base is yellow perch (young of year).
- Other important prey species are emerald shiner, sculpin, freshwater shrimp and Ephemeroptera (mayflies).
- Ephemerptera create a unique fishery in early-summer, as they are abundant with most species of fish feeding on them.
- Lake trout fishery is maintained entirely by natural reproduction (no stocking).
- The 2012 Skaneateles Lake stocking was 5,000 Finger Lakes Strain Wild (FLW) and 15,000 Finger Lakes Hybrid (FLW X domestic) rainbow trout, and 9000 Atlantic salmon stocked.
- Cisco numbers appear to be down in Skaneateles Lake. During the 1989 Standard Gang Netting 152 cisco were captured, only eight in 2008, and zero in 2012.
- VHSv (Viral Hemorrhagic Septicemia) was found in the lake in 2006 and may be a possible cause.
- 2012 angler diary cooperator legal fish/trip was 1.32 lake trout, 0.34 rainbow trout, 0.01 Atlantic salmon.
- Lengths of harvested salmonids by angler diary cooperators have increased in last few years, as have smallmouth bass lengths.
- Five year angler diary cooperator average is 14 cooperators and 224 trips.
- The 2012 angler diary cooperator legal fish/trip was 0.06 for tiger musky, 0.29 for largemouth bass, 0.47 for smallmouth bass, 0.25 for walleye and 0.06 for brown trout.
- Brown trout length limit regulation was changed from 15" to 12" on October 2012. This regulation was changed to maximize harvest given limited holdover due to high summer water temperatures and low summer dissolved oxygen (DO).
- Tiger musky (TGM) legal length limit regulation was changed October 2012 from 30" legal size length to 36". The regulation change was done to increase trophy potential.
- A 30" TGM is approx. 4-5 years old, and a 36" is approx. 6-7. Please be patient as it will take a few years to notice the effects of the regulation change.
- There is significant ice fishing effort and catch for TGM. 12 of 26 (46%) TGM caught by angler diary cooperators in 2012 were caught ice fishing.
- Catch per unit of effort (CPUE) for angler diary cooperators targeting walleye was 5.9 hr/fish and 6.5 hr/legal fish. The NYS range for "good" to "very good" walleye fishing is 10 to 4 hr/fish.
- CPUE for angler diary cooperators targeting black bass was 2.3 hr/fish and 3.2 hr/ legal fish. NYS mean for black bass is 1.9 hr/fish and 3.8 hr/legal fish.
- The 2012 Otisco Lake stocking was 44,000 walleye, 2,500 brown trout, and 11,000 tiger musky.
- In 2014 a Full Fish Community Assessment will be undertaken to evaluate 50-day walleye fry stocking experiment.
- Public access is a major concern for Otisco Lake. A DEC boat launch at Onondaga County Park is still in discussion phase.
- Water Chestnut was first found in the lake in 2007. There is a yearly inspection and removal of water chestnut. This group effort is undertaken by the DEC, Otisco lake preservation association and Cornell cooperative extension.
- The 2012 Cayuga Lake fish stocking was 55,000 lake trout, 55,000 rainbow trout, 20,000 brown trout and 28,000 Atlantic salmon.
- Cayuga Lake is an important propagation lake for both lake and rainbow trout egg collections.
- 2012 angler diary cooperator legal fish/trip consisted of 1.32 for lake trout, 0.02 for rainbow trout, 0.10 for brown trout and 0.28 for Atlantic salmon.
- Cayuga Inlet Fishway serves many functions such as: monitor the spring run of rainbow trout and sea lamprey; collection of biological data such as numbers, length, weight, sex, and sea lamprey scarring; egg collection point for Finger Lakes wild and hybrid rainbow trout.
- Invasive Species currently of concern in the lake are sea lamprey, hydrilla and spiny water flea. Species that may have future impact are Asian clam and round goby.
- Sea lampreys are not eels. Sea lampreys are primitive jawless fish with no paired fins.
- Adult sea lampreys enter tributaries to spawn. Build a horse shoe shaped nest, spawn and then die. Ammocoetes (juvenile non-parasitic lamprey) spend 3+ years burrowed in the silt, mud or sandy areas of a stream filter feeding. They then transform into parasitic lamprey (transformers) and leave tributaries and migrate into the lake. They spend the next 1 ½ years parasitizing fish.
- Sea lamprey fisheries objective is to manage the fishery while maintaining sea lamprey attacks below the following rates:
- lake trout 23.5-27.5"-0.2 adult sea lamprey attacks per fish.
- rainbow trout 20-22"-0.3 adult sea lamprey attacks per fish.
- Monitor sea lamprey wounding by checking lake trout for scarring during the fall egg take and summer standard gang nettings. Also monitor rainbow trout for scarring at the Cayuga Inlet Fishway in spring. Sea lamprey nest counts are done during early summer on major tributaries, and fall electrofishing is done on the inlet to assess ammocoetes number and sizes.
- Cayuga Inlet is a major sea lamprey spawning tributary. It has not been treated with lampricide since 1996. As most years, a barrier at the Cayuga Inlet Fishway is sufficient to stop/remove sea lamprey on their spawning run.
- Sea lampreys were able to get above the barrier on Cayuga Inlet in 2007 and spawn successfully.
- With nest counts and fall ammocoete shocking, we knew they were abundant, but decided to "ride it out" and not do a lampricide treatment. We underestimated how many there were in the system from that 2007 year class.
- The 2007 year class was very abundant in Cayuga Lake in 2012. Scarring rates increased and was very noticeable to anglers.
- In 2011 sea lamprey were once again able to get around the fishway barrier, and spawn successfully in the Inlet.
- Plan on treating the Inlet in 2014 to remove this 2011 year class before they transform.
- Lampricide is carefully metered into the stream at a rate dependent on the amount of water in the stream and the amount of lampricide needed to kill the lampreys.
- Lake Sturgeon Restoration began in 1993 with an initial stocking. These sturgeon are getting close to being mature and reproducing.
- Lake sturgeon are on the threatened fishes list, so you cannot target them when angling. If you catch one it must be released unharmed.
- The 2012 Owasco Lake stocking was 25,000 rainbow trout, 10,000 brown trout and 10,500 lake trout.
- Lake trout stocking has seen long term reductions.
- The significant walleye stockings occurred from 1996 to 2006. The Owasco Lake Anglers Association stocked from 1996-2001 and DEC from 2002-2006.
- Angler diary cooperator trips dropped below 250 in 2008 and has remained low since.
- Good mix of lake trout, rainbow trout and brown trout (including some real trophies) throughout the 1990s.
- Lake trout angler catch rates increased through early 2000s despite the population declining since the mid to late 1990s.
- The sharp declines in the brown trout and rainbow trout fisheries in the early 2000s coincided with the emergence of walleye in the fishery.
- Walleye and lake trout are both long lived and prey on stocked trout (and themselves!) and the effects of stocking changes take time.
- We maintained viable fisheries for brown trout and rainbow trout during and following peak lake trout abundance.
- The timing of the emergence of walleye in the fishery make them prime suspects contributing to the disappearance of the fisheries for brown trout and rainbow trout.
- So far we have taken steps in an attempt to recover the fisheries for brown trout and rainbow trout.
- The loss of these fisheries was not discussed as an acceptable consequence of the walleye program.
- Have not stocked walleye since 2006.
- Reduced lake trout stocking over the long term.
- Continued stocking brown trout and rainbow trout.
- We need to determine if this is the desirable direction (preferred by most) to take the fishery. Some anglers prefer walleye over trout, while other anglers prefer trout over walleye. We will not continue to manage the lake for both.
- We are doing a survey in 2013 to assess angler desires.