Volume 26 Study G-I STATE OF ALASKA Bill Sheffield, Governor Annual Performance Report for INVENTORY AND CATALOGING OF SPORT FISH AND SPORT FISH WATERS OF WESTERN ALASKA Kenneth T. Alt ALASKA DEPARTMENT OF FISH AND GAME Don W. Collinsworth, Commissioner DIVISION OF SPORT FISH E. Richard Logan, Director Volume 26 Study G-I RESEARCH PROJECT SEGMENT State: Alaska Name: Sport Fish Investigati ons of Alaska Project: F-9-17 Study: G-I Study Title: INVENTORY AND CATALOGING Job: G-I-P-6 Job Title: Alaska Cooperator: Kenneth T. Alt Part 6: Nowitna and Fish- Niukluk River Study, Western Alaska Creel Census, Sheefish Enhancement Assessment Period Covered: July 1, 1984 to June 30, 1985 ABSTRACT The Nowitna River is a lowland-type river of central Alaska. Major fish associations are northern pike, Esox Zucius Linnaeus, sheefish, Stenodus Zeucichthys (GUldenstadt), broad whitefish, Coregonus nasus (Pallas), humpback whitefish, Coregonus pidschian (Gmelin), and least cisco, Coregonus sardineZZa (Valenciennes). A few salmon, Oncorhynchus sp., and grayling, ThymaZZus arcticus (Pallas), are found in the upper reaches. Spawning grounds of the local Nowitna River sheefish population were located in early September, 20-35 miles up the Sulukna River. The Fish-Niukluk River on the Seward Peninsula is primarfly a clear, gravel- bottomed system. Major fish associations are pink salmon, Oncorhynchus gorbuschu (Walbaum) , chum salmon, Oncorhynchus keta (Walbaum), coho salmon, Oncorhynchus kisutch (Walbaum) , grayling, and Dolly Varden char , Salve Zinus maZm (Walbaum). Pike and humpback whitefish are found in the lower river. Data on life history aspects of major species, the fishery, and stream surveys are presented for the Nowitna and Fish-Niukluk systems. Important recreational fisheries in the management area were monitored during peaks of activity. Fishery trends indicate that the Unalakleet River and Kanektok River chinook salmon, Oncorhynchus tshmytscha (Walbaum), fishery,the Kobuk River sheefish fishery, and the Walker Lake lake trout, I I Salvelinus namaycush (Walbaum), fishery are harvesting fish at levels similar to 1983. Information on growth and survival of sheefish stocked in interior Alaska waters is presented. KEY WORDS Nowitna River, Fish-Niukluk River, pike, sheefish, whitefish, stream survey, salmon, grayling, char, harvest monitoring, sheefish enhancement. BACKGROUND Research on the Nowitna River began in 1967 with summer and fall monitoring of the pike and sheefish harvest. In 1972 a 3-year sheefish tagging study began on the Nowitna River and other middle Yukon River streams. The tagging study, in conjunction with preliminary stream surveys in 1973 and 1975, indicated that Nowitna River sheefish might constitute a local popula- tion separate from the anadromous lower Yukon population. Spawning fish were located at the mouth of the Sulukna River, but specific spawning grounds were not found. Fish-Niukluk River research began in 1972 with harvest checks at Council and continued sporadically through 1978. In 1978 and 1979 age-length-weight information was collected on char and grayling. The present study began in 1980 and was conducted for 4 years. Western Alaska creel census programs have been carried out through the years as harvest trend studies. A statistically based creel census is not practi- cal because of budgetary limitations and generally light fishing pressure and harvest. Rather, the status of the fishery and population can often be assessed by short visits to observe the fishery and to talk to local resi- dents and fishermen. The sheefish lake and river adaptability study began in 1967 as a sheefish egg take and expanded to cover incubation, rearing, stocking, and assess- ment. With the completion of the Clear Hatchery, the Fisheries Rehabili- tation, Enhancement and Development (FRED) Division has taken report responsibility for the egg take, hatching, rearing, and stocking segments, while the Sport Fish Division conducts assessment studies. Common and scientific names of fishes in the study area are listed in Table 1. RECOMMENDATIONS Research 1. Efforts should be made to locate spawning grounds of sheefish upstream of Rampart. -136- Table 1. List of common names, scientific names, and abbreviations. ____ Common Name Scientific Name and Author Abbreviation Alaska blackf ish Dallia pectoraZis Bean BF Arctic char SaZvelinus alpinus (Linnaeus) AC Arctic grayling ThymaZZus arcticus (Pallas) GR Arctic lamprey Lampetra japonica (Martens) AL Bering cisco Coregonus Zaurettae Bean BCI Broad whitefish Coregonus msus (Pallas) BWF Burbot Lota Zota (Linnaeus) BB Chinook salmon Oncorhynchus tshawytscha (Walbaum) KS Chum salmon Oncorhynchus keta (Walbaum) cs Coho salmon Oncorhynchus kisutch (Walbaum) ss Dolly Varden SaZveZinus malma (Walbaum) DV Humpback whitefish Coregonus pidschian (Gmelin) HWF 1t Inconnu (sheefish) Stenodus Zeucichthys (Guldenstadt) SF Lake trout Salvetinus nwnaycush (Walbaum) LT Least cisco Coregonus sardinella (Valenciennes) LCI Longnose sucker Catostomus catostomus Forster LNS Pink salmon Oncorhynchus gorbuschd (Walbaum) PS Round whitefish Prosopiwn cytindracem (Pallas) RWF Slimy sculpin Cottus cognatus Richardson ssc Sockeye salmon Oncorhynchus nerka (Walbaum) RS -137- 2. The fisheries resources of small, south-flowing streams of the lower Yukon River should be surveyed. 3. Rainbow trout studies should be initiated in the waters of Kuskokwim Bay and Kuskokwim River. 4. Monitoring growth of and survival studies of sheefish stocked in waters of interior Alaska should continue. Management 1. Monitoring of important recreational fisheries for sheefish, rainbow trout, lake trout, Dolly Varden char, pike, grayling, and salmon in the Westward Management Area should continue. OBJECTIVES 1. To complete the physical-biological survey of the Fish-Niukluk River. 2. To determine movements, run timing and distribution of Arctic char (Dolly Varden) , grayling, northern pike, sheef ish, and whitefish in the waters of the study area. 3. To collect angler and subsistence use information on important species within the job area, with emphasis on the Kobuk, Holitna, Fish-Niukluk, Kanektok, and Nome areas. 4. To continue evaluation of sheefish stocked in various interior Alaska waters. Note: Objectives are not exactly as in Job Description because G-I-P Job Objectives cover Jobs G-I-P, parts A and B. Those Objectives not referred to in part B are omitted. TECHNIQUES USED Techniques used to sample fish, conduct stream surveys, and count anglers are similar to past years (Alt, 1983, 1984). FINDINGS Nowitna-Sulukna River Survey The Nowitna River (Fig. 1) heads in the Kuskokwim, Sunshine, Von Frank, and Mystery Mountains of central Alaska and flows generally northeast for 250 mi to empty into the Yukon River at lat. 64'56' N. and long 154'16' W. The river is locally called "The Novi" or "Novi River," but the names Nowi River, Novikakat, Newicargut, and Noyakakat are also used. -138- ~~~ Figure 1. Nowitna River with major tributaries. -139- The Nowitna meanders extensively in its lower reaches as it travels through the Nowitna lowlands. The extensive lake and slough system in the lower river provides excellent habitat for waterfowl, moose, bear, and adult and juvenile fish. The river has excellent sport fisheries for pike and sheefish. Pike up to 32 lb and sheefish up to 33 lb have been caught here. Stream survey work began in 1967 and test-netting activities continued mainly in the lower river on an irregular basis through 1984. Most activities were related to a sheefish life history study (Alt, 1973, 1974, 1975, 1978). Most research was conducted in the lower river. For this report the Nowitna River was divided into sections, with each succeeding section having different stream characteristics. Section I: Section I includes the lower 90 mi of river from the mouth to the confluence of the Little Mud River. This section of the river meanders considerably, has a sand and mud bottom over most of its course, and contains numerous sloughs and lakes. The current is slow (approx. 1 mi/hr), the water is stained brown, stream width varies from 200 to 450 ft, and stream depth from 3 to 12 ft. The river generally has a high mud cutbank with sand and mud bars on the inside bends of the river. The river is heavily vegetated with willow, alder, birch, aspen, and spruce. Water temperature ranged from 40°F in late May and early June, to 68'F in July. Extensive gill-netting was conducted in the lower river in various years. Catch composition in early spring was quite similar from year to year. For example, in 1972, during 50 net-nights of fishing with 80-100ft nets of 63-in stretched mesh in various areas near the mouth, 140 sheefish, 500 broad whitefish, 20 suckers, 39 humpback whitefish and 91 pike were captured. Fourteen net-nights of fishing with a 125ft graduated mesh net took 38 sheefish, 46 broad whitefish, 8 humpback whitefish, 25 pike, 2 Bering cisco, 11 least cisco, and 6 suckers. Nets set during 4 net-nights of fishing in mid-September took 20 pike, 6 sheefish, 2 broad whitefish, and 6 humpback whitefish. Most sport fishing in the Nowitna occurs in the lower 20 mi of the river, with pike and sheefish the target species. Sheefish are captured in the main river and mouths of sloughs and tributaries. Pike are more often found in sloughs, such as Johnson Slough, but are also captured in the main river. The river has long been known as a trophy pike stream and pike over 20 lb in weight are the main attraction. Harvest of sheefish is more sporadic, as they are less abundant in the lower river as the spawning population moves farther upstream later in the summer. A considerable amount of fishing occurs in conjunction with fall moose hunting. The major tributary in Section I is the Sulatna River. Novakaket Slough is a distributary of the Nowitna. Most Nowitna River pike spawning occurs in Section I, with sloughs off the main river containing the most important habitat. Additionally, Section I provides feeding and rearing habitat for pike, sheef ish, burbot , suckers, and various species of whitefish.