What You'll Find at Blue Mesa

Blue Mesa Reservoir holds some of the largest kokanee salmon and lake trout in Colorado, along with brown trout, rainbow trout, and smallmouth bass. The water sits at 7,500 feet on the Gunnison Plateau, so it stays cold year-round — even in summer the thermocline keeps the deep water in the 40s. This cold-water fishery rewards anglers who understand depth, structure, and seasonal movement rather than those who rely on warm-water patterns.

The reservoir covers about 9,500 acres when full, with steep canyon walls on the north and east sides and more gradual terrain to the south and west. Underwater ridges, old creek channels, and the original Gunnison River channel create the structure that holds fish. Unlike desert reservoirs in Arizona or New Mexico, Blue Mesa's elevation and snowmelt cycle mean water levels fluctuate significantly — sometimes dropping 40 feet or more from spring to fall.

Key Takeaways

  • Kokanee salmon and lake trout dominate the fishery, with kokanee reaching 16 inches and lake trout regularly exceeding 20 inches in the deeper basins.
  • Summer fishing requires trolling or jigging in water 60 to 120 feet deep, where fish retreat to escape the warm surface layer.
  • Spring and fall allow shallower fishing near structure, with brown trout and rainbows moving into 20 to 40 feet of water.
  • The Gunnison River arm at the north end of the reservoir offers different conditions than the main basin and holds fish year-round in specific zones.
  • Water level changes throughout the season affect boat launch access and the location of productive structure.

Kokanee Salmon: The Dominant Summer Target

Kokanee are the most abundant fish at Blue Mesa and the reason many anglers make the drive to this plateau reservoir. They school heavily in summer, moving into the deepest water available — typically 80 to 120 feet — to find water cold enough for their metabolism. Trolling small spoons (size 0 to 1) in silver, chartreuse, or pink works best, with the spoon trailing 40 to 60 feet behind the boat on a downrigger or lead-core line.

The key to consistent kokanee fishing is finding the thermocline, the layer where water temperature drops sharply. A fish finder with temperature capability shows this line clearly. Kokanee hold just above or within the thermocline, where they find both cold water and the zooplankton they feed on. Troll slowly — 1.5 to 2.5 miles per hour — and adjust depth as you move across the basin. The deeper basins near the dam and in the central reservoir hold the most fish in July and August.

Fall brings a change. As water cools in September and October, kokanee move shallower and become more aggressive. Jigging with small spoons in 40 to 60 feet of water produces well, and you may find feeding fish in 20 to 30 feet near structure. This is the season when shore anglers can reach kokanee from the dam area and the north arm.

Lake Trout and Brown Trout in Deep and Shallow Water

Lake trout at Blue Mesa grow large because the cold water and abundant forage support fast growth. Fish in the 18 to 24-inch range are common, and specimens over 28 inches are caught every season. Lake trout are less schooled than kokanee and more solitary, holding near structure — drop-offs, ridges, and the old river channel. In summer, they occupy similar depths to kokanee but often hold slightly deeper, in the 100 to 150-foot range.

Trolling larger spoons (size 2 to 3) and swimbaits works for lake trout, but jigging is often more effective. Drop a 1 to 2-ounce spoon or a tube jig to the bottom near structure, then work it with sharp lifts and pauses. Lake trout respond to the erratic motion and the vertical presentation. The north arm of the reservoir, where the Gunnison River enters, holds lake trout year-round in specific deep holes.

Brown trout and rainbows are secondary targets but worth pursuing in spring and fall when they move into shallower water. Browns often hold near the dam and in the deeper coves, feeding on small fish and crustaceans. Rainbows are more scattered but concentrate near inflows and in the upper arms of the reservoir. Trolling small streamers or casting spinners near structure can produce, especially in May and September.

Seasonal Patterns and Water Level Effects

Blue Mesa's water level is managed for irrigation and power generation, not for recreation, so it changes dramatically through the year. Spring runoff (April through June) raises the level, flooding new structure and pushing fish into different zones. Summer drawdown (July through September) lowers the reservoir 20 to 40 feet, concentrating fish in the remaining deep water but also exposing new shallow structure that holds fish in fall.

Spring fishing (April through May) is often overlooked but can be excellent. As water warms slightly and inflows bring nutrients, fish move shallower and feed more actively. Trolling in 30 to 60 feet of water near the river arms and coves produces kokanee, browns, and rainbows. The north arm, where the Gunnison River enters, is especially productive because current brings food and cooler water.

Summer (June through August) is the peak season for numbers, but it requires deep-water techniques and patience. Fall (September through October) offers the best combination of accessibility and fish activity — water is cool enough to keep fish active, but they move shallow enough for shore anglers and smaller boats to reach them. Winter fishing is possible but limited by weather and ice formation in protected bays.

Launch Sites and Access Points

The main boat launch is at Lake Fork Marina, on the south side of the reservoir near the town of Blue Mesa. This launch has a paved ramp, fuel, and a store. It is the most reliable access year-round and handles the heaviest traffic. Elk Creek Marina, on the north side, offers another paved launch with fewer crowds but sometimes closes earlier in fall if water levels drop.

Shore fishing is possible from several points. The dam area allows walk-in access and is productive for kokanee and lake trout in fall and winter. The Gunnison River arm has pull-offs and informal access points, though water level changes affect where you can safely fish. Check current conditions with the ranger station or marinas before planning a trip, as water levels and access change throughout the season.

Tackle and Technique Essentials

A medium-action trolling rod with a level-wind reel or a spinning reel spooled with 8 to 12-pound monofilament or braid works for most Blue Mesa fishing. For kokanee, downriggers or lead-core line are nearly essential in summer — they let you reach the 80 to 120-foot depths where fish hold. A fish finder with temperature and depth capability is worth the investment; it shows you the thermocline and helps you locate structure.

Jigging rods should be sensitive and relatively short (5 to 6 feet) to feel the bottom and detect strikes. A 1 to 2-ounce spoon or tube jig is standard. For trolling, carry spoons in multiple sizes and colors — kokanee respond to small, flashy spoons, while lake trout often prefer larger profiles. Swimbaits in 3 to 4-inch sizes also produce well for lake trout.

Bring extra line and leaders. The rocky bottom and structure at Blue Mesa cause breakoffs, and having the ability to re-rig quickly keeps you fishing. A net is useful for landing larger lake trout, and a cooler with ice preserves fish quality if you plan to keep them.

Regulations and Seasons

Blue Mesa is open year-round to fishing, but regulations change by species and season. Colorado Parks and Wildlife sets the rules, which typically allow year-round fishing for kokanee and lake trout with standard daily limits. Brown trout and rainbow trout have specific seasons and may have reduced limits during spawning periods. Check the current Colorado fishing brochure or the Parks and Wildlife website before your trip — regulations change annually.

A Colorado fishing license is required for all anglers 16 and older. Licenses are available online, at sporting goods stores, and at the marinas. If you plan to fish multiple times, an annual license is more economical than daily licenses.

Frequently Asked Questions

What's the best time of year to fish Blue Mesa?

Summer (June through August) offers the most consistent fishing for kokanee and lake trout, but requires deep-water techniques. Fall (September through October) is often better for anglers who prefer shallower water and more active fish. Spring can be excellent but is less predictable. Winter is possible but challenging due to weather and ice.

Do I need a boat to fish Blue Mesa?

A boat is helpful for reaching the deep water where most fish hold in summer, but shore fishing is productive in fall and winter, especially near the dam and the north arm. If you don't have a boat, plan your trip for September through November when fish move shallower.

What size kokanee and lake trout should I expect?

Kokanee average 12 to 16 inches, with some reaching 18 inches. Lake trout average 18 to 24 inches, and fish over 28 inches are caught regularly. Both species grow well in Blue Mesa's cold, productive water.

How deep do I need to fish in summer?

In summer, kokanee typically hold 80 to 120 feet deep, and lake trout hold 100 to 150 feet deep. A downrigger or lead-core line is nearly essential to reach these depths consistently. A fish finder helps you locate the thermocline and adjust your depth as conditions change.

Can water level changes affect my fishing plans?

Yes. Blue Mesa's level drops significantly from spring to fall, sometimes 40 feet or more. This concentrates fish in deeper water but also exposes new shallow structure. Check current water levels with the marinas or ranger station before your trip, as it affects both where fish hold and where you can safely launch.