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Landlocked Salmon *Salmo salar* The landlocked salmon (Salmo salar)is one of the most prized game fish in the Northeast. First found in Maine and southeastern Canada, it may be native to Lake Champlain and has since been distributed throughout North America and Europe. There are no physical differences between the landlocked salmon, which spends its entire life in fresh water, and the sea-run Atlantic salmon, which spends most of its adult life in salt water. Both are leapers and keep the angler's adrenaline flowing. Physical Description There are several developmental stages of the landlocked salmon. The first stage is in the form of an egg. Hundreds of round orange eggs, about 1/4 of an inch in diameter, are laid by the female clustered together in what is known as a redd. After hatching, the small, one inch sized fish is referred to as an alevin. The alevin has a yolk sac attached to its belly, which serves as a food source for the developing young salmon. At the next stage, known as the fry, the young salmon is about one to two inches in length and has fully developed fins. The tail is deeply forked and there are no skin markings visible yet. However, the fry soon grows to two to six inches long, and is now considered a parr. At this time in its life, marks appear which are dark, vertical oval spots on their sides, which serve as camouflage for it life in the stream. The parr matures into a smolt; a critical time in the young salmon's life as it prepares to migrate from the stream in which it was born to the lake it will inhabit as an adult. A smolt averages six to 12 inches in length, its skin is silvery with no parr marks on the side but some spots on its back, and the tail is less forked in shape. The adult is the final stage Size can vary considerably, ranging from eight to 24 inches in length. Its body is silver with darker coloring on its back and tail. Its tail is a solid black and is square in shape, but is usually notched at the middle of the trailing edge. Young salmon and trout look very similar. The adipose fin, which is the tab-fin on the back of the fish just ahead of its tail, is always a solid color on salmon, either grayish or black, but never with black spots or red/orange splotches. Except on very small fish, the salmon's tail is also nearly always solid colored, black in maturity and gray on young fish. On very young fish, the tail has a solid colored band at its outer edge, which widens toward the body as the fish grows until the tail is all one color. The tail is usually forked or indented midway along the trailing edge, but the notch is less noticeable on older fish. The maxillary or upper jaw usually ends in front of the eye in salmon, whereas in trout it extends to behind the eye. Yearling salmon can grow four to six inches in a couple of months. In Vermont, landlocked salmon generally reach ten inches after their first year, 12 inches by two years of age, 15 inches after three to four years of age, and 17 inches by their fifth year. In some waters where smelt abundant, two and three-year old salmon have been caught weighing one and half to three pounds and measuring 15 to 20 inches in length. The Vermont record (1994) was 12.65 pounds, caught in Lake Champlain by Brian Latulippe of Winooski. Life Cycle Adult salmon spawn in October and November using the inlet or outlet streams of their resident lake. Female salmon generally reach maturity during their fourth or fifth year. Males develop faster, maturing by their third or fourth year and even as young as one and two-year olds. At breeding time, the lower jaw of the male grows a prominent, turned up hook called a "kype." Individual salmon may spawn annually or every other year. Some may spawn for two consecutive years and then skip a year but studies indicate that these individuals are primarily alternate year spawners. Up to 90 percent of a spawning run, however, consists of salmon spawning for the first time. Spawning salmon prefer gravel riffle areas, just above or below pools in swift moving water. The female salmon excavates a series of pits and covers them with gravel, which is known as a redd, in an area with little silt or sand. She may dig several egg pits over a week's time to contain her eggs. The eggs are deposited at night in the gravel at a depth of four to twelve inches. A single female produces 600 to 700 eggs per pound of her body weight. The male swims alongside the female and fertilizes the eggs, by releasing milt, a milky white fluid that contains sperm, into the water. The egg incubation period averages 150 days although it varies in different areas according to water temperatures. After hatching, "sac fry", or alevins, remain in the gravel, living off nutrients absorbed from the yolk sac, until their yolk sac is gone, usually in late April. Then the young fry work their way up through the coarse gravel into the riffle and boulder areas and start to feed on aquatic insects. Once they reach two inches in length, the fry develop dark bars, or parr marks, on their sides. At this life stage they are called parr. Both fry and parr use rocks, woody debris and vegetation for cover from predators in fast moving water. Young salmon spend one to three years in the stream before another physiological change takes place. The fish get the urge to move to larger waters, and prepare to do so by transforming into smolt. The smolt migrates to the lake. Once in the lake, its growth rate increases rapidly. Growth rates vary from lake to lake, but in Vermont, salmon grow best where smelt are abundant. Within one to two years after smolting occurs, an adult reaches sexual maturity, and continues the salmon life cycle by spawning. Most landlocked salmon caught by anglers are two to four-year olds, although the oldest landlocked salmon on record, taken in Maine, was thirteen years of age. Annual mortality rates range from 40 to 60 percent. In lakes with a good salmon fishery, anglers probably account for about 20 to 30 percent of this mortality. Trophy size salmon are usually well over six years old, but they make up only two to ten percent of the fishery. Food Items The landlocked salmon’s diet depends on its developmental level and food availability. Alevins feed on the yolk sac that is attached to its belly. Fry and parr feed on small aquatic insects, larvae and nymphs of water dwelling flies like the mayfly and caddisfly. Smolts feed mainly on fish, supplementing their diet with insects from the water surface. Adult landlocked salmon feed mainly on fish, smelt. In addition, the adults will also forage insects from the surface of the lake. Habits & Habitat Adult salmon prefer clear cold lakes with maximum temperatures around 70 to 75 degrees Fahrenheit. In the spring, adult salmon use the relatively warmer water near the surface, and will move to cooler deeper water as summer progresses. A pH around 6.0-7.0 is needed for salmon to thrive. A lake needs to have streams with adequate spawning and rearing habitat to sustain a naturally reproducing population. For spawning, the female selects a site within an inlet or outlet stream of its resident lake that has gravel rather than silt or sand on the bottom. Good spawning habitat also has layers of stones that are about 1/2 to four inches in diameter, as this will allow for an adequate water flow in the redd. To assure proper oxygenation of the eggs, the female generally builds the redd in the downstream end of a pool or the upstream end of a riffle. As the eggs hatch, the alevin utilize the same habitat, finding shelter within the loose gravel of this area. Both the fry and parr develop in similar areas. This nursery habitat includes primarily shallow water interspersed with deeper pools and riffles. Large pebbles or rocks and vegetation are also present to provide the young salmon with food and cover. Again, well-oxygenated water is important, as is the water temperature. Optimal fish growth occurs in streams with peak temperatures of 72 to 77 degree Fahrenheit. The cooler the water, the slower the growth of the fish. Abundance The quality and accessibility of spawning and nursery areas largely determine the population of the landlocked salmon in Vermont. History Many theories have been advanced about the origin and development of the landlocked strain. The most widely accepted opinion is that the preference for freshwater was a physiological change that occurred through evolution. In nearly all waters where landlocked salmon were first found, there was access to the sea. Landlocked salmon are generally found in deep, cold, well-oxygenated lakes where there is little competition from other species. But successful populations have also been established in marginal lakes having relatively shallow waters and competition from other species. Resource Utilization The landlocked salmon is a favorite among anglers. Its keen sense of smell, hearing, and taste allow it to easily sense danger making this fish a true challenge to catch. The meat from the salmon is also prized. Management Efforts The landlocked salmon fisheries around the state are progressing well, but fishermen should realize that the Fish and Wildlife Department is still stocking sub-legal one and two year old fish into lakes and will continue to do so out of necessity. It is unjustifiably expensive to raise legal size fish, because hatchery space is limited, and the larger size fish would demand too much space at the hatchery. Secondly, smaller fish acclimate better to natural conditions, and varied age-classes are important to any established fishery. Thirdly, spawning salmon need large tributaries and most of our salmon lakes do not have them. For some or all of the above reasons, sub-legal fish have to be stocked. Unfortunately, small fish are more readily caught than large ones, and anglers should learn how to properly release sub-legal-size fish so they will survive. The majority of lakes stocked in Vermont are in the Northeast Kingdom, with the exception of Lake Champlain, Lake Dunmore, and Harriman Reservoir. A fish passage facility is maintained on the lowest Winooski River dam to allow adults access from Lake Champlain to the spawning habitats upstream of the dam. All lakes are stocked with one and two year olds. In addition, the Clyde River (a tributary of Lake Memphremagog) and the Winooski and Lamoille Rivers are stocked with fry. Both smolt and fry stocking are being evaluated to assess their success in achieving naturally reproducing landlocked salmon populations in the stocked lakes and rivers.