DEVELOPMENT of TROUT FISHERIES in the ROCKY MOUNTAIN REGION with an OVERVIEW of FISH CULTURE, WILD TROUT and FISHERIES MANAGEMENT by Robert W
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DEVELOPMENT OF TROUT FISHERIES IN THE ROCKY MOUNTAIN REGION WITH AN OVERVIEW OF FISH CULTURE, WILD TROUT AND FISHERIES MANAGEMENT by Robert W. Wiley Fisheries Research Supervisor Wyoming Game and Fish Department ivi.e.S • 528 South Adams Laramie, Wyoming 82070 Wild trout and planted trout; the natural as opposed to the manmade. A virtual tug-o-war among interests has developed over wild and planted trout. Fish culture and fisheries management, plus the expectations of society, are entwined in a web of contrdversy about trout management. What caused and fuels the trout debate; what roles have fish culture and fisheries management played; and where is the balance between wild and planted trout? A historical perspective on fishing in Wyoming (and the rest of the Rocky Mountain Area), the development of fish culture, and &iota:410-K fisheries management gives foctis to the issue. EARLY TROUT FISHING AND FISH CULTURE Trout fishing in parts of Wyoming Territory in the late 19th Century was excellent. In July 1876, General Crook's soldiers reported catching 15,000 trout (on hook and line with and grasshoppers) from streams in the valley of Tongue River near Sheridan (Bourke 1891). When they moved on, the soldiers had enough smoked and salted trout, packed in barrels, to last many days. Wyoming appointed its first sh commissioner in 1879 to control fishing and stock streak (Table 1). Trout arrived and were planted in 1880 and Ar'state fish hatchery was completed in 1884. The hatchery was built because streams and lakes were either devoid of trout or existing trout stocks were depleted by overharvest, pollution, dam building, unscreened irrigation diversions, and the use of dynamite to harvest fish. Trout Were also considered a food source by residents and economic benefit because anglers would come to fish and spend money (Barkwell 1883). _ Commissioners Louis/Miller (1890) and Gustave Schnitger (1895) felt that annual :planting, like yearly reseeding of agricultural crops, was necessary to maintain good trout fishing. Schnitger (1896) thought tliat Wyoming's waters could support 2,500 trout per acrer54re Wyoming6 trout culture system flourished under this premise. By 1918, it was estimated that every water in the state had been stocked- with trout and there was interest in raising even more 1notxt (Lenihan 1918). Table 1. Historical record.of fish culture, fisheries management, trout introductions, and fishing regulations in Rocky Mountain states( haee.44-.5 a reepx; ruaft, date) a State Fish Fish Trout Fish Fish admin laws introduced hatchery management Arizona 1887 1887 01900 1922 1950 Colorado 1877 1872 1872 1881 @ 1950 Idaho 1900 1883 1889 1897 1938 Montana 1895. 1865 621880 1908 1947 Mew Mexico 1897 * 1883 1950 Utah 1874 1853 (31877 1899 1950 Wyoming 1879 1869 1880 1884 1950 Trout fishing and trout culture followed about the same course throughout the Rocky Mountain Region (Rawley and Rawley 1972; Sigler and Sigler 1986; Wiley 1993; Table 1). As human population rose, the number of trout hatcheries and the number of planted trout also increased. There was some awareness of -native trout, but the idea that trout fishing and trout populations could be improved by stocking was the buo16,1„e6 / order of the day. In Wyoming, early (1920-1949) fisheakilgwalmaessiii6tr pegodebelieved that 80-90% of the trout planted in state rearing ponds survived to be caught by anglers (Cook 1936). The outlook appeared to be the same wherever trout were planted. THE ROLE OF FISH CULTURE Trout were planted in virtually any water that looked suitable and were often introduced where there had been no trout. For example, good trout fisheries in the Laramie and Platte rivers (where trout are not native) were reported by the 1890's (Miller 1890) and rainbow trout eggs for the state fish hatchery were collected from these streams. By the turn of the centuryitT;put hatcheries were operating in most Rocky Mountain statesplanting millions of trout each year. Most "biological" surveys before 1950 were conducted by fish culture people. They were looking for suitable fish *planting sites, places to build more fish hatcheries, or sites for additional rearing ponds. A few surveys in Utah were conducted by university professors who catalogued th productivity of various waters (Sigler and Sigler 1986), 11the information was probably used to decide where to locate additional hatcheries to raise and stock more trout. There is no dou that trout hatcheries are important to good angling, conspfving and protecting stocks of native fish, maintainin fisheries in lakes and reservoirs, and jar' reintroductio4,following natural disasters or pollution. However, anglers and fisheries biologists can expect too much from them. Modern surveys show that 55-96% of trout standing stocks in streams in the western United States are 160 pounds per acre (Platts and McHenry 1988; Wiley 1993)C. Virtually all trout streams in Wyoming have stocks of 200 pounds per acre or less, far lower than the 2,500 pounds per acre surmised by Gustave Schnitger (1896). The outlook during the early years focused on trout culture, trout planting, and trout harvest as a commodity, like an agricultural crop. Extensive trout culture and • planting began throughout the West in the 1880's and 'led people to believe in and expect that good fishing was the result of trout planting. Hobbs (1948) reported that 75 years of trout planting had caused generations of New Zealanders to expect trout to be planted. He believed that trout planting in New Zealand was beneficial, but that much of it was unnecessary. Recent angler surveys in Wyoming show almost universal support for stocking hatchery trout (Anderson et al. 1990). Trout culturists have done their job wery well. Generally, hatchery-reared trout are in good condition, healthy, and apparently ready for post-planting life. Livingston Stone (1872)yeported that the salmon and trout he raised were healthy l ,Blat the also wondered if the fish, even. though he lthy, could survive better in the hatchery than in the wild after planting. Over a century of trout management literature shows that planted trout often survive poorly after planting..(Wiley et al. 1993). To assess the health and condition of planted and wild trout, Goede (1986) developed an autopsy-based fish analysis system. With this method, biologists and fish culturists can determine how well planted fish are suited for post-planting life in the wild and how well they adjust to life in streams and lakes after planting. .14,TILD TROUT AND HATCHERY TROUT Wild trout seem to occupy stream habitat to its productive capacity (Platts and McHenry 1988). Supplementing wild trout stocks is usually not successful in increasing trout standing stocks unless the population has been reduced from some disaster. Hatchery trout do not survive any better than wild trout in stream habitat, whether pristine or degraded because they have the same biological requirements. Wild trout do best in streams becaus they111e' were born there and are attuned to the vagaries of7 habitat. Hatchery trout are reared in circumstances much different fr9m natural streams (i.e.) densities hundreds of times those in the wild, virtually constant water temperature and flow, regular feeding, and no predators). Survival rates from egg to planting of 80% are common for hatchery-reared trout. Survival rates of wild trout from eggs to the end of their first year are 1-5%. frA lie Early fish culturists (Stone 1872; Schn ger 1892) realized that they were altering natural se ection by raising trout in protected hatchery environments. tone was concerned that the trout he raised might not do well after planting. Research in the ensuing century has shown his concerns to be well-founded, as a rule hatchery trout do not survive well in streams. Trout do not reproduce in many lakes and reservoirs, so to maintain populations, hatchery-reared trout must be stocked. Trout stocked in lakes survive best when there are few or no competing fish, including carryover trout from previous plantings (Wiley et al 1993). Where large predatory trout are present or where zooplankton of the size trout prefer is depressed, planted trout survive poorly. So, even with regular planting, trout populations fluctuate similar to their wild counterparts. -t-m/ lf,d . e THE: ROLE OF FISHERIES MANAGEMENT h=== Fisheries managers, exclusive of fish culturists, were first employed.in the Rocky Mountain Region in 1938 in Idaho (Table 1). Management based on stream and lake surveys and fish planting protocols were proposed for Wyoming in 1940 (Simon 1940), 10 years before fish management crews were established. Simon knew that native cutthroat trout Oncorhynchus clarki were being extirpated from much of their range by non-native trout planted earlier. His management protocol was that golden trout 0. aguabonita would be planted at highest elevations, followed in descending progression by . cutthroat trout,.brook trout Salvelinus fontinalis, rainbow . trout 0. my-kiss, and brown trout Salmo trutta. It provided further that brown trout would be planted only with forage fish and that lake trout Salvelinus namaycush would be planted with no other game fish. Fish planting was not permitted without stream and lake surveys to determine productivity and presence of competing species. Wyoming's first fish managers were hired in 1950, coinciding with the federal aid to sport fish restoration program. Greene (1950) reported closure of many state-sponsored trout rearing ponds because biological surveys showed that they were producing at about 15% of anticipated yield. Some of the ponds had been operating for 30 years. Currently, rearing ponds are used at fish hatcheries where trout are fed and production is monitored. ----- lita_aaart_Eialaing_Inatitm±g. The Sport Fishing . Institute (SFI), an organization dedicated to good management of fisheries in North America, began about 1960.