Large Lake Fisheries in New Hampshire
By Don Miller
The majority of New Hampshire's large lakes are located in the central part of the state. Lakes Winnipesaukee, Winnisquam, Squam, Newfound, Sunapee, Ossipee, Wentworth, Conway and Merrymeeting exceed 72,000 square acres of water. These lakes are diverse and offer both cold and warm water fisheries. Most of these lakes are stocked annually with rainbow trout and landlocked salmon. All other species found in the lakes are self-sufficient and reproduce naturally in the system. Thanks to an abundance of cold, deep-water habitat, these lakes all contain rainbow smelt. Smelt are perhaps the most important forage species for our coldwater sportfish. Lake trout and landlocked salmon are dependent upon healthy populations of these bait fish in order to attain good growth and body condition. Rainbow trout also prey upon smelt, although they thrive upon a great variety of other food items.
One of the major goals in the Large Lakes Fisheries Program is to provide quality recreational fisheries for trout and salmon by maintaining abundant populations of rainbow smelt. We monitor smelt populations every summer through our nighttime hydroacoustic sonar surveys on the big lakes. Smelt numbers are quantified and biomass estimates are calculated for a number of our coldwater lakes every year. This data allows us to adjust the stocking rate for landlocked salmon, in order to allow for their maximum growth while affording protection to our smelt populations. Smelt abundance can be critically affected by over-stocking of salmon. In addition to summer surveys, spring spawning of smelt is documented and studied to gain further insight into the age-class structure of the state's smelt populations.
Each fall we set a variety of nets in several large lakes to capture landlocked salmon, rainbow and lake trout. Through this population sampling, we examine hundreds of trout and salmon to gain information on their general health and condition. We also capture and hold several hundred landlocked salmon for egg stripping purposes for our statewide salmon stocking program. A popular event, "Salmon Sunday" is held in November at the department's Pope Dam facility in Melvin Village, on the north shore of Lake Winnipesaukee. Hundreds of anglers and their families have seen our salmon stripping process "up close and personal" at this annual event.
We have embarked on annual surveys of young-of-the-year (YOY) bass in Lake Winnipesaukee through the warmwater program. These surveys will allow us to make predictions about bass year-class strength and monitor the reproductive success of our large lake bass populations.
While smelt are just one component to a healthy lake ecosystem, all species of fish in our large lakes are indelibly entwined in the web of life. We strive to maintain healthy populations of cold and warmwater fish in our large lakes. As a partner with lake associations, state agencies, municipalities and private landowners, we share the common goal of protection of our lakes and their diverse habitats.