Skilak Lake is a hidden gem awaiting adventure lovers across the United States, located in the Kenai Peninsula of southcentral Alaska. Known for its pristine waters, picturesque scenery, and authentic Alaskan experience, Skilak Lake sits near the eastern border of the Kenai National Wildlife Refuge.
Skilak Lake has a surface area of approximately 24,700 acres (100 km2), and a treacherous maximum depth of over 500 feet (152.4 m). This nearly bottomless lake owes its features to the glacial movements from which it was formed. In fact, the lake is still sustained by glacial activities, receiving runoff from the adjacent Skilak Glacier, in addition to inflow from the Kenai River.
There are plenty of massive fish awaiting in Skilak Lake, including cold-water specialists like trout and salmon. Fishing for all species is open year-round. There are two boat launches located on the northern coast of the lake at the Lower and Upper Skilak Lake Campgrounds. While Skilak Lake is best suited for boat fishing, anglers should diligently practice safety precautions, as high winds and unpredictable glacial discharge can make boating dangerous.
Skilak Lake Fish Species
1) Sockeye salmon (Oncorhynchus nerka)
Sockeye salmon go by many names— kokanee salmon, blueback salmon, or sockeyes for short— though the most befitting moniker is “red salmon”, which aptly describes this species’ seasonal transformation to bright scarlet on their entire bodies, except for their heads and fins. This change in pigmentation occurs when fish turn 2 – 5 years old and subsequently travel upstream to spawn.
Before spawning, sockeye salmon reside in marine and brackish habitats, where their bodies sport a glimmering silver with blue backs. Fish die after reproducing in a reproductive strategy known as semelparity. The kokanee version of the sockeye salmon remains in freshwater habitats throughout its entire life.
Sockeye salmon in the Kenai River system are plentiful, as the basin serves as a nursery for fish from the Cook Inlet. Sockeyes here have three runs throughout the year— an early run in May, a second run in June, and a final passage in July and August. Not only are sockeye salmon responsible for sustaining salmon fishing in the area, but they also support the local food chain by providing sustenance for other organisms in and around the lake. Coho salmon feed on sockeye fry, while bald eagles and bears readily hunt conspicuous breeding fish from the water.
2) Coho salmon (Oncorhynchus kisutch)
Though coho salmon can grow up to a massive 30 inches (76.2 cm) long and weigh between 8 and 12 pounds (3.6 and 5.4 kg), juvenile salmon are minuscule creatures that make a delicious meal for other fish in Skilak Lake. Since they can’t protect themselves with their size, young coho salmon possess 8 – 12 ovoid bands called parr marks running along the lateral line that are used for camouflage. As fish age, parr marks fade. Like sockeyes, adult coho salmon turn a vivid red when they are ready to spawn, though the two can be distinguished by the tiny black spots on the coho salmon’s back that are absent in sockeyes.
Young coho salmon can only survive in cool temperatures and well-aerated water. They usually reside near the lake’s shallow banks, where they hide in underwater woody structures. Freshly hatched salmon (called alevin) absorb nutrients from a yolk sack that they are born with, while older juveniles eat plankton, insects, and salmon eggs. Breeding adults are less particular in their habitat selection and will occupy any gravelly area that they can claim as their territory. Like sockeye salmon, coho adults die after spawning, though their remains are valuable in contributing the nitrogen and phosphorous that their offspring need to grow to the lake’s nutrient load.
3) Pink salmon (Oncorhynchus gorbuscha)
The pink salmon is the smallest member of the Pacific salmon and trout genus, Oncorhynchus, found in North America. They reach between 20 – 25 inches (50.8 – 63.5 cm) long, and typically weigh no more than 5 pounds (2.3 kg). Pink salmon resemble their relatives, though they are differentiated by the comparatively large, cheetah-like spots that mark their backs and the entirety of their tails. Ichthyologists may peek inside a fish’s mouth for accurate identification— pink salmon have black gums, in contrast to coho salmon, which have a white gum line.
Between June and October, breeding males develop a monstrous form featuring drastically curved jaws and a huge, bulging back. Because of their reproductive physique, pink salmon are also called humpback salmon. They do not develop the bright red pigmentation of coho and sockeye salmon and spend significantly less time in freshwater due to their brief 2-year life cycle.
Pink salmon is the most abundant salmon in the United States, and the majority of the country’s pink salmon is harvested from Alaska. It is highly valued for commercial fisheries, generating $181.8 million from the state’s commercial yield in 2021. Pink salmon is processed and sold in canned, frozen, and other pre-packaged forms. The species is generally not utilized for salmon oil production due to its low oil content.
4) Dolly Varden trout (Salvelinus malma)
The origin of the Dolly Varden trout’s unique common name is a minor mystery, though it is attributed to Elda McCloud, niece of a previous owner of the Soda Springs Resort in North Carolina. The name has two possible origins— either a character in Charles Dickens’ Barnaby Rudge, or a red-spotted fabric sold in the 1860s under the same name. Regardless, Dolly Varden have become one of the most popular sport fish in Alaska, known for their aggressive fighting that often ends with snapped fishing lines.
Dolly Varden are true chars, characterized by dark green-gray flanks dotted with bright yellow to pink marks. They were originally considered the same species as the bull trout (S. confluentus), but the two were divided in 1978. Two subspecies exist in Alaska, the larger, northern variety (S. m. malma) with 66 – 70 vertebrae, and the smaller, southern variety (S. m. lordi) with 62 – 65. Dolly Varden can be migratory or lake-bound, with some fish regularly entering Skilak Lake to feed on young sockeye salmon. Permanent lake residents are often dwarfed, attaining lengths of only 3 – 6 inches (7.6 – 15.2 cm).
5) Lake trout (Salvelinus namaycush)
Lake trout are one of the longest-lived trout species. Their average maximum lifespan is around 20 years old, though some remarkable individuals in Alaska can live for as long as 50 years! They are a slow-growing species that spend most of their time deep within Skilak Lake’s water column and are one of few recreational fish that can tolerate low-nutrient conditions.
Lake trout growth is often temperature-dependent, and fish have been found to grow faster during years with warmer spring temperatures. This is an indirect effect that stems from the bottom of the food chain— faster post-winter thawing of the lake increases plankton production. This in turn provides more food directly for lake trout that adopt a planktivorous diet, as well as indirectly for bigger individuals that prefer crustaceans and fish.
Lake trout fishing is best in the spring when they enter shallow waters to escape the frigid temperatures at the bottom of the lake. In shallow water and near the lake’s banks, they are best caught using bright spinners and spoons. Trolling can be used to capture fish in the summer when they return to waters greater than 45 feet (13.7 m) below the surface. The creel limit for lake trout over 20 inches (50.8 cm) in Skilak Lake is 2 per day, while anglers can collect up to 10 individuals less than 20 inches each day.
6) Rainbow trout (Oncorhynchus mykiss)
Rainbow trout stand out even among the many colorful residents of Skilak Lake, with metallic bodies entirely covered in black, freckle-like marks, spotted fins, and green-brown backs. The most notable characteristic of the rainbow trout is its iridescent pink lateral streak that starts from the blushing gill cover and extends toward the tail peduncle.
Rainbow trout have a relatively protracted spawning period, starting in March and ending in July. During this time, the lower jaws of male fish adopt a slight hook-like form known as a kype, which is used to ward off other males competing for a mate. The presence of a kype can also be used by anglers to determine the sex of a catch.
Females dig nests with their tails in shallow, rocky areas, where they lay anywhere from 200 to 8,000 eggs. Rainbow trout eggs take a long time to hatch, and unfavorable temperatures can prolong fry emergence for up to four months after fertilization! Though adults are solitary, young rainbow trout group together as a defensive tactic against predators. A school of rainbow trout is called a hover.
7) Round whitefish (Prosopium cylindraceum)
Round whitefish get their name from their cylindrical bodies. In fact, the species epithet translates from Greek as “like a cylinder”. They are characterized by light silver bodies with yellow-orange pectoral, pelvic, anal, and caudal fins that become even more vivid during spawning season. Round whitefish have abrupt snouts with a slight overbite that helps them suck up insects, mollusks, crustaceans, fish eggs, and zooplankton from the lake floor. Though they are generally bottom-feeders, anglers can find round whitefish at a variety of depths. They are difficult to catch because of their small mouths and reluctance to bite at lures that are bigger than their tiny prey.
Like many fish species found throughout Skilak Lake, round whitefish are migratory, though their migration pattern does not extend into the ocean. Fish that migrate within freshwater but do not enter marine habitats are said to be potamodromous. Unlike most other whitefish, round whitefish spawn during the day.
