Now Booking For 2026
Now Booking For 2026
The Kenai and Kasilof Rivers are renowned for hosting some of the world’s largest Chinook salmon, commonly known as king salmon. In fact, these pristine glacial rivers on Alaska’s Kenai Peninsula are home to distinct runs of Alaska King Salmon, with the Kenai River holding the world record for sport-caught king salmon at a staggering 97 pounds, 4 ounces, caught by Les Anderson in 1985. While the average size of Kenai kings ranges from 25-50 pounds, it’s not uncommon for anglers to battle fish topping 75+ pounds. The Kasilof River also boasts impressive Alaska King Salmon, with the largest reaching over 50 pounds, a testament to the exceptional genetics found in these river systems.
The Kenai River spans 82 miles from Kenai Lake to Cook Inlet, and has ideal water temperature, gravel, and riparian habitat for spawning fish and king fry. The river’s flow rates fluctuate in summer from 6,000-15,000 cubic feet per second, influenced by snowmelt and rainfall. Occasional glacier ice dam releases result in flood events where flows can top 18,000 – 20,000 cfs.
The Kasilof River is a shorter river, at 17 miles from Tustumena Lake to Cook Inlet. It is also a glacier-fed river featuring cool, oxygenated waters and excellent clean spawning gravel.
The Kenai River hosts two distinct runs of king salmon. The early run, entering the river from mid-May through June, typically numbers between 3,000 to 5,000 fish. These kings average 40-60 pounds and primarily spawn in tributary streams. The late run spans late June and July, and sees higher overall numbers of fish. Between 10,000 to 25,000 fish arrive on the late run, and these kings often reach larger sizes, averaging 50-75 pounds. They primarily spawn in the main stem of the river.
The Kasilof River similarly experiences two runs, though smaller in size. The early run, enhanced by hatchery production, enters from mid-May through June, with typical returns of 3,000 to 6,000 fish. The late run Kasilof kings arrive during July, and while the run isn’t officially counted, it’s estimated to be a similar size or slightly larger run. In contrast to the early run, the late run kings are all wild fish. These naturally produced kings represent an important pool of genetic diversity.
Kenai and Kasilof Kings typically spend 3-5 years in the ocean before returning to spawn. Scale analysis by the Alaska Department of Fish and Game indicates that the largest specimens are usually 6-year-old fish that have spent 4 years feeding in the nutrient-rich Pacific. Over the course of the spawning migration their bodies undergo remarkable physiological changes.
During their freshwater entry, the fish cease feeding, relying entirely on stored fat reserves. Their meat transitions from bright orange to pale pink as they near spawning, while their external coloration changes from bright silver to deep red or maroon. Males develop the characteristic hooked jaw (kype) and a taller back, while females maintain a more streamlined profile as they prepare to deposit 4,000-14,000 eggs in carefully selected gravel beds.
Looking for the first shot at Alaska’s King Salmon? Drifter’s Lodge offers guided fishing trips on the Kasilof River, renowned for its unique early run of hatchery-supported King Salmon. Beginning in May, these powerful fish enter the Kasilof, providing an exceptional opportunity to battle a trophy King before the main summer crowds arrive. Our expert guides specialize in Kasilof River King Salmon fishing trips, and they’ll put you on the fish using proven techniques. We offer both drift boat and bank fishing options on the Kasilof, depending on your preference. Experience the thrill of early-season King Salmon fishing with Drifter’s Lodge and make memories that will last a lifetime.
