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Alberta’s Cutthroat Trout Stocking Program. Barry Mitchell photo. Alberta Environment and Sustainable Resource Development. Outline. This presentation is intended to provide a summary of the purpose for, and activities involved in Alberta’s Cutthroat Trout Stocking Program, including:
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Alberta’s Cutthroat Trout Stocking Program Barry Mitchell photo Alberta Environment and Sustainable Resource Development
Outline This presentation is intended to provide a summary of the purpose for, and activities involved in Alberta’s Cutthroat Trout Stocking Program, including: • Background of the species and their qualities. • Development of a wild brood stock in and for Alberta. • Establishment of a field camp every two years to collect cutthroat eggs for culturing. • The egg collection and fertilization process. • Hatching, rearing and stocking of cutthroat trout. • The types of fisheries that result. • Program benefits to Albertans.
Background • Cutthroat trout are native to the upper Bow River and Oldman River systems in Alberta. • They have been introduced widely into the upper Red Deer and North Saskatchewan River systems, and to a lesser degree in the Wapiti River system (Torrens River). • They are very hardy, and able to thrive in less-productive headwater streams and high elevation lakes. • Cutthroat trout are sought after by anglers partly due to being easily caught, but also for the remote and scenic places they live. Barry Mitchell photo
Background (cont’d) • The genetic compatibility of stocked fish is important to prevent tainting of native stocks. • Many of Alberta’s high country lakes could not be stocked if cutthroat trout were unavailable.
Alberta’s Cutthroat Brood Stock • Cutthroat were first stocked into streams and lakes in Alberta during the 1950’s, creating some very good fisheries (i.e. Ram R. system), and a number of self-sustaining populations. • Since then, this species has been stocked into high country habitats, most of which were historically barren of fish. • In order to ensure a supply of fish for stocking, and to secure their genetic integrity, ESRD Fisheries Management decided to stock cutthroat trout into one high country lake for the purpose of establishing a brood stock. • Compared to the cost of maintaining a captive brood stock, using a wild brood stock is very cost-effective.
Brood Stock (cont’d) • After a review of potential lakes, Job Lake was selected. It is a remote lake located about 55 km west of Nordegg. • It was first stocked in 1966 with native west slope cut-throat from the Upper Bow River system (Marvel Lake). • The fish grew well in Job Lake, and began to reproduce by spawning in the outlet stream.
Brood Stock (cont’d) • Cutthroat trout eggs were first collected from the Job Lake brood stock in 1970, and then annually until 1992. • Since 1992, egg collection has occurred every second year. • All of the cutthroat trout needed for stocking in Alberta since 1970 have come from the Job Lake brood stock. • Angling at Job Lake was allowed until 1989, when it was closed due to over-harvest and user impacts to the sensitive environment.
Job Lake Field Camp • Based on the well-documented timing of cutthroat spawning at Job Lake, Fisheries Management staff plan and conduct an egg collection every two years. • The lake is accessed by helicopter for the late May to early June project.
Job Lake Field Camp (cont’d) • The crew establishes a temporary field camp for the duration of operations. • Weather is highly variable at that time of year, and can range from summer to winter conditions.
Capture of Cutthroat Trout • The Job Lake cutthroat trout assemble to spawn near and in the lake’s outlet each spring. • The outlet stream is blocked by net to prevent fish from moving downstream. • Ice removal from the outlet area is often required to facilitate fish capture. Ice is cut by chainsaw, and chipped with a needle bar to flow down the outlet.
Capture of Cutthroat Trout (cont’d) • Fish are captured at night with a beach seine net when they are attempting to move down the outlet, or are assembled along the beach to spawn. • Once caught, they are sorted and placed in holding cages according to sex and stage of maturity.
Capture of Cutthroat Trout (cont’d) • Fish capture continues each night until the required number of cutthroat are on hand (usually 3 – 4 nights). • The number of fish required (usually 1,000 – 1,200) is determined according to that year’s stocking needs. • Stripping of eggs and sperm from the cutthroat is planned for the next day. Dave & Amelia Jensen photo
Preparations for Egg Collection • Radio communication is used to confirm a helicopter for the delivery of fertilized eggs to the Calgary hatchery, as previously arranged. • All of the necessary equipment is assembled and prepared for the following day’s operation. • Only dedicated or new equipment is used at the lake, to prevent the spread of fish diseases. • A large tent with a wood stove is used for the spawning operation, to ensure the eggs and sperm are not subject to damage by ultra-violet radiation (sunlight) or freezing.
Cutthroat Trout Egg Collection • Starting at sunrise, fish are anaesthetized in tubs at the holding pens, then brought in to the tent to conduct the stripping of eggs and sperm. • Aerated tubs of lake water are used to hold fish before and after stripping.
Cutthroat Trout Egg Collection (cont’d) • Females are individually stripped into a basin, and the eggs examined for any obvious problems. • Only good-quality eggs are retained for fertilization. • Males are individually stripped into a basin, and the condition of sperm is recorded. • Spent fish are returned to holding pens in the lake.
Cutthroat Trout Egg Collection (cont’d) • The sperm is drawn up into a syringe, and a minimum of one milliliter is used to fertilize the eggs of each female. • After the sperm is added, a stimulant is used to hasten and extend the fertilization process. • The eggs are stirred with a feather, then set aside for several minutes to allow complete fertilization.
Cutthroat Trout Egg Collection (cont’d) • After fertilization, the eggs are rinsed and then packed in a cooler of aerated water for transportation. • The eggs are left undisturbed for a minimum of two hours, as they are vulnerable to damage by movement at that time.
Cutthroat Trout Egg Collection (cont’d) • Before shipping, a volumetric estimate is made to ensure a sufficient number of eggs are on hand. • Around mid-afternoon, the egg coolers are loaded into a helicopter bound for Calgary.
Monitoring the Brood Stock • The next day, the crew processes all captive trout. • Fish are measured, weighed, and sexed. • Some fish have tags from past years; new fish are tagged, all for purposes of monitoring the adult cutthroat population. • Records are kept of relevant details, particularly the fish recaptures from previous years. • Fish are held overnight to recover, then released.
Cutthroat Trout at the Hatchery • After the egg coolers arrive at the Calgary airport, they are taken by vehicle to the Sam Livingston Fish Hatchery. • Once there, they are un-packed and rinsed with a disinfectant.
Cutthroat Trout at the Hatchery (cont’d) • The eggs are placed in up-welling jars to keep fresh water flowing past them, at around 8°C. The incubation phase has begun. • After about 20 days, eyes are clearly visible, and the eggs are sorted by machine to remove any dead ones.
Cutthroat Trout at the Hatchery (cont’d) • The eggs are counted to determine the number of viable eggs remaining ... … then placed in trays for the next stage of incubation, at 7,000 eggs per tray.
Cutthroat Trout at the Hatchery (cont’d) • Around 30 trays are necessary to accommodate the Cutthroat Trout eggs from Job Lake. • They are placed in a flow-through incubation system. • Each tray is hand picked twice per week to remove dead eggs, which helps prevent fungal growth.
Cutthroat Trout at the Hatchery (cont’d) • After about 36 days of incu-bation, the fish hatch from their transparent egg shells. • They remain in trays for another 20 days, or until their yolk sac has been consumed. • The cutthroat fry are then placed in rearing troughs of flow-through water at around 10°C. • They are first fed at this time, using starter feed comprised of fish meal, ground grains, vitamins and minerals. • A sub-sample are tested for disease.
Cutthroat Trout at the Hatchery (cont’d) • After about 100 days at the hatchery, the small trout are ready for stocking. • Fish to be stocked back into the brood lake (Job Lake) are mildly anaesthetized for handling, then permanently marked by a lip clip. • This is done to monitor the proportion of the spawning population that came from stocking versus natural reproduction.
Egg and Fry Survival • From egg collection to stocking, trout survival has ranged from less than 10% in some of the early years, to over 75% in recent years. • Survival improved significantly due to changes in operations at the lake, and experimentation, namely: • A controlled environment to collect eggs (heated tent, shade from sun). • Careful handling of fish. • Close attention to water temperatures during fertilization, rinsing, and in the egg coolers. • Discarding of eggs of questionable condition. • No increase in elevation (and a gradual decrease) during the flight of eggs to the hatchery.
Procedures • A comprehensive Procedures Manual has been developed for the entire operation, which is carefully followed.
Stocking Cutthroat Trout • In September, the young trout are hauled by hatchery truck to various distribution points along Alberta’s eastern slopes. • Fish are sorted into batches according to each destination water body, then placed in aerated containers.
Stocking Cutthroat Trout (cont’d) • They are loaded into a heli-copter, and have continuously supplied aeration. • The fish are then flown to their destination water body, and released.
Stocking Cutthroat Trout (cont’d) • From the Job Lake stock, over 2.6 million cutthroat trout have been stocked into over 130 different water bodies in Alberta since 1970. • All of those water bodies are situated in the foothills and mountains, ranging from the Pincher Creek District to the Grande Prairie District. • Many of these waters are remote, requiring access by hiking, horseback or helicopter. • A number of streams, and a few lakes, are accessible by road.
Fishing Cutthroat Trout • Anglers who enjoy the high country appreciate the cutthroat trout opportunities that Alberta Fisheries Management has provided. Dave & Amelia Jensen photo Dave & Amelia Jensen photo
Fishing Cutthroat Trout (cont’d) • The opportunity to catch a trout in wild and scenic places is an important factor for anglers who exert the effort to fish the west country. Dave & Amelia Jensen photo
Fishing Cutthroat Trout (cont’d) • Alberta has realized some very successful cutthroat introductions into both lakes and streams … Barry Mitchell photo Dave & Amelia Jensen photo Dave & Amelia Jensen photo
Fishing Cutthroat Trout (cont’d) … for fish both large and small. Dave & Amelia Jensen photo Dave & Amelia Jensen photo
Benefits of the Cutthroat Stocking Program • Most of Alberta’s high country lake fisheries would cease to exist without the ability to stock cutthroat trout. • Stocking other trout species in high country lakes is seldom appropriate, due to genetic tainting of, and/or competition with, native stocks in the watershed. • Excellent survival and high catchability of stocked cutthroat, as well as their longevity (some live to age 10 or more), allows for a lower stocking rate and frequency than for most other stocked fisheries. • Catch rates of several fish per hour are common in both lakes and streams. Over 40 fish/hour has been recorded. • Many of the stream stockings are now self-sustaining. • Stocking cutthroat trout in Alberta’s high country creates some special fisheries in a very cost-effective way.
Program Endorsements “The cutthroat stocking program has benefited many anglers. Local and foreign anglers have enjoyed the mountain beauty in Alberta thanks to planting of cutthroat into mountain lakes and foothill rivers. Our guests have been thrilled to enjoy hiking, mountain biking, and helicopter access to some of the most scenic and incredible fly fishing opportunities. With more people now enjoying our waters, it is important that the program continue. Also, the success of the cutthroat trout stocking program on the Blackstone River has introduced a very good fishery available to many anglers. It has allowed more people to enjoy a fine cutthroat trout river with good access. All told, our company can attest that the cutthroat trout stocking program is very important." - Dave & Amelia Jensen, Fly Fish Alberta Dave & Amelia Jensen photo Dave & Amelia Jensen photo
Program Endorsements (cont’d) “Fishing for cutthroat trout in Alberta is near and dear to me. Nothing I could say about the importance of cutthroat trout stocking and management could describe it any better than the photo of my daughter catching Cutts with her daughter (my granddaughter) and her nephew on a foothills stream. Those kids, and the ones coming after them, are who you fisheries managers are doing all this for.” - Barry Mitchell, Alberta Fishing Guide Magazine Barry Mitchell photo Barry Mitchell photo
Photo Credits All photos by Alberta Environment and Sustainable Resource Development staff, except where noted otherwise. Dave & Amelia Jensen photo Dave & Amelia Jensen photo This presentation prepared by Rocky Konynenbelt, Rocky Mountain House, AB.