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  By Harvey Thommasen, with Photography by Mark Hume Early spring is the time to search for sea-run Dolly Varden in coastal streams. At this time of year Dolly Varden are voracious feeders, as they are brought into play by one of the most significant hatches of the year - the emergence of salmon fry.
Although extraordinary fishing can be had by fishing a fry imitation, like a Rolled Muddler, experience has taught me that, perhaps surprisingly, they will take a dry fly as readily as a salmon fry imitation. As the best way to fish a fry imitation is on a dry line, it’s easy enough to switch over to a dry pattern, to experiment. The response of Dolly Varden, which are clearly feeding on schools of out migrating salmon fry, can be startling. Perhaps it’s because they are essentially surface feeding, lying on the bottom and charging up to take fry that they see in silhouette, or perhaps it’s because they welcome a change after feeding so heavily on the fry. Whatever the reason, the char, which are firm and lean at this time of year, will often pass up fry to smash a dry fly on the surface. When they take a fry pattern fished near the surface on a floating line, their dolphin-like takes can be graceful, head and tail rises, or violent slashes. Sometimes in the spring you can look down a run, and see swirls and violent surface splashes - sure signs that Dolly Varden are feeding on fry. As a general rule, few Dolly Varden exceed 2 kg (4.4 lbs) in weight. While Dolly Varden do resemble trout in size and body shape, they are easily recognized by the presence of many round pale yellow, orange or red spots along both sides of the body. Their backs are olive green with deep green wavy markings, and the pectoral, pelvic and anal fins have a pinkish-white border. Sea-run Dolly Varden fresh from the sea tend to be very silvery along the sides, so silvery that the spots are often barely visible. As with most fish, one must observe the spawning fish to truly appreciate the beauty of the species. Spawning Dolly Varden, particularly the males, are stunning fish. The face becomes outlined in black, the spots become a vivid orange and red, the belly becomes orange and the fins a fiery red. Spawning takes place in streams from late October into November. Once spawning is completed no one is sure what happens to sea-run Dolly Varden in British Columbia streams. Studies from Alaska suggest that many of the males die after spawning, but up to 50% of females survive to spawn again. Survivors likely leave the spawning tributaries, then move upstream to overwinter in a lake. The eggs hatch in spring, at about the same time salmon eggs are hatching. Winter survival of eggs to yolk sac fry is relatively high - averaging 40% or more. Dolly Varden fry begin to feed actively as soon as they emerge from their redds. They tend to live close to the banks and stagnant parts of the river where they feed on mayfly, stonefly and midge larvae, amphipods, water mites, and adult flies trapped on the water surface. Larger fry will also eat the smaller fry of other fish species. The young fry have 8 to 10 wide dark parr marks, oval eyes which slope together toward the top of the head, and a tail which is not deeply notched and which has broadly rounded upper and lower lobes.
Young sea-run Dolly Varden spend most of their first, second, third and sometimes fourth years (age 0, 1, 2, and 3) in freshwater before migrating to sea as smolts the following spring. Dolly Varden smolts leave their nursery streams, usually under the cover of darkness, from early May to late June with the peak usually being mid-May to early June. They are long, thin, silvery colored with large heads, and range in size from 100 to 180 mm fork length. Typically they head out shortly after chum and pink fry have exited the system. One wonders if a Dolly Varden smolt fry might not attract strikes from larger fish at this time of year. After entering the ocean, Dolly Varden can wander a considerable distance from their home stream - up to 300 km in some tagging studies. They are usually found within 500m of shoreline where they forage for a variety of invertebrate species. Most young sea-run Dolly Varden return to fresh water streams by September and October after spending three to four months in saltwater. Few of the first time returners will spawn. They will have to wait another year before they are large enough and mature enough. Like the spawners, the non-spawners probably overwinter in the safety of upstream deep pools or lake waters. After winter is over Dolly Varden leave their wintering lakes or deep river pools and move back to the ocean in early spring, feeding on fry as they go. They also eat aquatic insects (eg caddis fly larvae and chironomids), outmigrating salmon fry, Dolly Varden young, sculpin eggs, and sticklebacks. While in salt water anadromous Dolly Varden eat mainly capelin, sand lance, herring and crustaceans (Mysidae, Euphausidae, Gammaridae, Crab larvae), polychaete worms and the occasional salmon fry. During the immigration back into freshwater, sea-run Dolly Varden consume aquatic insects and salmon eggs found drifting along the gravel bottom. Sea-run Dolly Varden wintering in lakes feed on aquatic insects, isopods, freshwater clam larvae and other bottom organisms. They will also take the occasional leech and sockeye salmon fry. Compared with salmon, sea-run Dolly Varden are a slow growing fish. Unlike salmon which can grow up to 6 cm (2 inches) / month during the marine phase of their lives, sea-run Dolly Varden grow at a maximum rate of about 1 cm (0.4 inches) / month. After four months in the ocean some of the larger, more mature Dolly Varden return to their home streams at the end of June and July. By August and September most have returned for winter. Peak numbers moving upstream appears to be around mid-July. Studies show that the majority of fish move upstream between 2200 to 2400 hrs, and that spawning fish move upstream at a rate of 0.4 km (0.25 mile) per week. So when you encounter them during the day, they are probably holding fish, resting after moving up the night before. Few sea-run Dolly Varden live longer than 9 years. I have always enjoyed catching sea-run Dolly Varden, particularly in the early spring as they move out of the system, feeding heavily. They can be caught in the lower side streams in many coastal rivers through the summer months, as the fish move back in to mature for spawning; and they can be caught in the late fall as they move up rivers to over wintering in lakes. Many people feel sea-run Dolly Varden are an inferior sports fish and a nuisance, because they are a major predator of salmon and trout. That is why one can still sometimes find dead Dolly Varden along stream banks, where misguided fishermen have thrown them, thinking they are removing an unwanted preadator from a river. That mentality is a throw back to the late 1920's to 1950's when predator control was a common management "tool". During this time the government paid bounties for the destruction of almost all predatory birds and mammals in British Columbia. The bounties on eagles, hawks, owls and other predacious birds was gradually eliminated between 1924 and 1931 after a quarter of million birds had been killed; the bounty on cougars, wolves and coyotes persisted until the late 1950's. Between 1909 and 1955 bounties were paid on over 25,500 dead wolves. In the early 1900's sea-run Dolly Varden were singled out as being the most serious predator of salmon young and eggs. This "fact" was based on the finding that during the fry outmigration anglers caught char that were stuffed full of sockeye fry. Ignoring the obvious fact that many other salmonid species feed upon salmon eggs and fry during their life history, Alaska Fish and Game Managers instituted a large scale bounty program on sea-run Dolly Varden. Over 6 million sea-run Dolly Varden char were destroyed, and more than $300,000 was spent between 1921 and 1940. The program was cancelled in 1941, and has since been called one of the greatest boondoggles in the history of Fisheries Management. The program was based on little or no research. And the majority of tails turned in for bounty were actually from rainbow trout and salmon - the very species they were attempting to save! It is understood today that Dolly Varden play an important role in coastal stream ecosystems. By cleaning up dead salmon eggs they prevent development of diseases; by consuming smelt, sculpins, and sticklebacks, sea-run Dolly Varden remove competitors and predators of salmon and trout.
But the future of the species is uncertain. The slow growth and complex biology which characterize sea-run Dolly Varden make them a fragile fishery. Stocks are gradually disappearing from southern streams because of overfishing and habitat destruction. It is worth remembering that in some of the larger streams, sea-run Dolly Varden share the waters with Bull trout. Both are char, and look so much a like that only recently have Bull trout (Salvelinus confluentus) and Dolly Varden (Salvelinus malma) been classified as two distinct species. Up until 1978, fisheries scientists considered Bull trout to be part of the Dolly Varden (Salvelinus malma) complex. While Bull trout are generally thought of as river species, they are occasionally found in lakes as well. According to the International Game Fish Association: “as a general rule one can be fairly certain that any char other than lake trout or brook trout, weighing over 5 lbs taken in the bull/dolly range will prove to be a Bull trout; and fish over 12 lbs are almost certainly Bull trout.” If pressed for a qualitative expression of the two species forms, one can generally say that Bull trout have larger, broader, and flatter heads and their bodies are more slender and ventrally flattened. Others report that Bull trout never have spots or lines on their dorsal fin, but I am not sure how dependable this identifing characteristic is. In contrast, Dolly Varden have more oval and 'snake-like' bodies with their heads not dominating their profile. Hybrids appear to be rare. When in the same area, Dolly Varden and Bull trout exhibit strict sympatry with no evidence of interbreeeding. Dolly Varden appear to predominate in these sympatric populations in terms of numbers. As a general rule, Dolly Varden dominate coastal streams, whereas Bull-trout dominate interior streams and lakes. When salmon fry are migrating in the spring, big Bull trout can sometimes be found in shallow water - and they will take a fry pattern with heart stopping jolt. Will they rise to a dry fly too? It’s a good question, and one worth researching, next time you find a run, where the big fish are lying in wait for migrating salmon fry. |
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