Lake Trout
Lake trout, the largest of the char, are also Alaska’s largest resident freshwater fish, routinely reaching weights beyond 20 pounds. They are extremely opportunistic predators, preying on almost any obtainable food source, including other fish species that might be available.
A lover of the dark, deep nether regions where water temperatures are more to their liking, lake trout force anglers in most areas to cope with heavy rods, heavy metal, downriggers, and the tedium of a day spent trolling. Thankfully, a host of environmental factors bestows some distinction to the northern populations of lake trout. In many Alaska lakes, the water never warms up enough to stratify and establish a definite thermocline. While more latitude-challenged lakers must head for a lake’s nadir as soon as the summer sun begins to warm the water, the lake trout of Alaska can avail themselves to anglers year-round. Oftentimes these Alaska lake trout are caught on or right near the surface.
The average size of Alaska’s lake trout varies but is approximately four- to eight pounds. Ten-pound fish are not uncommon in much of the state, particularly in lakes that continue to receive less than systematic effort. In recent years, though, over-fishing in many of the most popular and accessible lakes has left a higher proportion of smaller fish. It’s hoped that more active management policies and a growing emphasis on angling ethics will restore the state’s most easily reached lake trout waters to their former quality.
Lake trout favor water temperatures of roughly 10°C (50°F), and they tend to avoid areas with less than about four parts per million of oxygen. In the more temperate regions of the species range, those requirements can usually only be met near the bottom of large, deep lakes that are low in nutrients. During the summer, only the upper layers of water in nutrient-rich lakes contain adequate oxygen concentrations, but these water layers are usually too warm for lake trout. Low-productivity lakes, with more suitable water, also have fewer food sources available. Thus, it usually takes an oligotrophic lake of more than 500 surface acres (200 hectares) to sustain an abundant lake trout population. In some areas of Alaska, especially in the lakes of the state’s Interior, these requirements are readily met.
When winter’s icy grip finally recedes from Alaska’s lakes, anglers are afforded a rare opportunity to have consistent success in lake shallows, or in places, on top. At this time of year, lake trout can be found anywhere in the water column, and after a long winter spent beneath the ice pack, they’re more than willing to chase a fly or lure. Add an annual smolt out-migration and you have all the ingredients for an explosive fishery. The warming of large oligotrophic lakes each spring (anywhere from late May through June) triggers a mass exodus of juvenile salmon bound for the sea. Lake trout stage at points of interception in shallow, shoreline waters or at the head of a stream outlet and capitalize on this most important staple of their diet. However, the out-migration usually doesn’t last for long, ranging from as little as a few days to as long as three weeks in length, depending on temperatures, the lake and the fecundity of the native salmon.
Anglers in quest of these smolt-slashing lakers will have their best success during the low-light hours of late evening. As a relative June darkness falls, smolt activity usually begins to peak, with daily runs reaching their height between the hours of 9 p.m. and midnight.
Within Alaska, lake trout can be found in the high elevation lakes of the Brooks Range and the lakes of the central and eastern Arctic coastal plain. They are distributed throughout the upper Tanana and Copper river drainages in the alpine lakes of the Alaska Range and in the watersheds draining into Bristol and Kuskokwim bays. Lake trout are generally absent from the lowland lakes of the North Slope and the Yukon and Kuskokwim river valleys, as well as from the Seward Peninsula and for the most part, the Wood River system. Finally, Alaska’s lake trout do not appear in the lakes and streams on the south side of the Alaska Peninsula or in northern Alaska Peninsula systems south of Mother Goose Lake. 
Popular spots like Paxson and Crosswind lakes and Lake Louise turn out trophy fish over 20 pounds every year even with mounting pressure. And the more remote but still road-accessible lakes off the Dalton and Denali highways can provide exceptional lake trout action, along with a good dose of solitude. Add to that the primeval wilderness fisheries of the Northwest and Arctic plain, where lake trout are known to be present in hundreds of drainages and can probably be found in a hundred more.