LIMNOLOGICAL AND SOCKEYE SALMON PRODUCTIVITY INVESTIGATIONS IN SALMON AND GLACIAL LAKES:

1994- 1995 PROJECT REPORT

G. L. Todd G. B. Kyle

REGIONAL INFORMATION REPORT' NO. 5J96-02

Alaska Department of Fish and Game Division of Commercial Fisheries

Management and Development P.O. Box 25526

Juneau, AK 99802-5526

February 1996

I The Report Information Report Series was established in 1987 to provide an information access system for all unpublished divisional reports. These reports frequently serve diverse ad hoc informational purposes or archives basic uninterpreted data. To accommodate timely reporting of recently collected information, reports in this series undergo only limited internal review and may contain preliminary data; this information may be subsequently finalized and published in the formal literature. Consequently, these reports should no be cited without approval of the author or the Division of Commercial Fisheries.

LEVNOLOGICAL AND SOCKEYE SALMON PRODUCTIVITY INVESTIGATIONS IN SALMON AND GLACIAL LAKES:

1994- 1995 PROJECT REPORT

G. L. Todd G. B. Kyle

REGIONAL INFORMATION REPORT NO. 5596-02

Alaska Department of Fish and Game Division of Commercial Fisheries Management and Development

P.O. Box 25526 Juneau, Alaska 99802-5526

February 1996

AUTHORS

Gary L. Todd is the project biologist for the Nome area lake investigations for the Alaska Department of Fish and Game, Limnology Unit, Division of Commercial Fisheries Management and Development, 34828 Kalifomsky Beach Road, Suite B, Soldotna Ak 99669.

Gary B. Kyle is the southcentral Regional Lirnnologist for the Alaska Department of Fish and Game, Limnology Unit, Division of Commercial Fisheries Management and Development, 34828 Kalifornsky Beach Road Suite B, Soldotna Ak 99669.

ACKNOWLEDGMENTS

We thank the following people involved with this joint project: Pete Velsko (ADF&G) for logistical support, Joe Webb (BLM) for logistical support and project planning, Richard Dederick (ADF&G) and Leah Weyapuk (KAWERAK) for Salmon Lake smolt and lirnnology data collection, Larry Wilhnott and Jason McClellan (BLM) for Glacial Lake smolt and Salmon Lake adult data collection, and Stan Carlson (ADF&G) for statistical support in data analysis.

TABLE OF CONTENTS

Section

7 ........................................................................................................................ INTRODUCTION - ........................................................................................................ Study Site Description 3

MATERIALS AND METHODS .................................................................................................... 3 Smolt Enumeration and Sampling ........................................................................................ 3 Adult Enumeration and Sampling ......................................................................................... 4 Limnology Surveys ............................................................................................................ 4

............................................................................................. Hydroacoustic/Townet survey 5

RESULTS ............................................................................................................................ 5 ......................................................................................... Smolt Abundance. Size. and Age 5 .

.......................................................................................... Adult Abundance. Size. and Age 5 Li~nnological Panmeter; .................................................................................................... 6

................... Light Penetration, Temperature, and Dissolved Oxygen 1 ................................. 6 General Water Chemistry ............................................................................................... 6 Nutrients ................................................................................................................. 7 Phytoplankton .............................................................................................................. 7 - ................................................................................................................... Zooplankton 1

Salmon Lake Hydroacoustic Estimate of Rearing Fish ............................................................ 8

DISCUSSION ............................................................................................................................ 8

RECOMMENDATIONS ............................................................................................................... 9

................................................................................................................ LITERATURE CITED 10

.......................................................................................................................... APPENDIX 31

LIST OF TABLES

Table - 1. Daily migration of sockeye salmon smolts from Glacial Lake, 1995.

2. Population estimate, size, and age of Glacial Lake sockeye salmon smolts by sample period, 1995.

3. Size and age of Salmon Lake sockeye salmon smolts, 1995.

4. Daily migration of sockeye salmon adults for Salmon Lake, 1995.

5. Mean len,@ and age composition of adult sockeye salmon sampled at Salmon Lake, 1995.

6. Aerial survey estimates of sockeye salmon in the Salmon Lake system and in Glacial Lake, and the harvest of sockeye salmon destined for Salmon Lake in the Port Clarence District, 1963- 1995.

7. Summary of lirnnological parameters (seasonal means by year, station, and depth) for Salmon Lake, 1994-1995.

8. Sumnary of limnological parameters (seasonal means by year, station, and depth) for Glacial Lake, 1994- 1995.

9. Summary of seasonal mean macro-zooplankton density and biomass in Salmon Lake, 1994- 1995.

10. Summary of seasonal mean macro-zooplankton density and biomass in Glacial Lake, 1994- 1995.

1 1. Densities and population estimates of juvenile fish r e a ~ g in Salmon Lake by transect based on the 26 September 1995 hydroacoustic survey.

12. Seasonal mean macro-zooplankton density and biomass for 20 sockeye salmon nursery lakes in Alaska, showing the relative comparison for Salmon and Glacial lakes.

LIST OF FIGURES

1. Map of the Nome area (Seward Peninsula) showing the location of Salmon and Glacial lakes, and the Pilgrim River.

2. Map of Salmon Lake showing general morphometric information, and the locations of the lirnnological survey stations and hydroacoustic transects.

3. Map of Glacial Lake showing general morphometric information, and locations of the lirnnological survey stations.

4. Migration timing by age class for sockeye salmon smolts emigrating Glacial Lake, 1995.

5. Mean density of edible and non-edible phytoplankton at 1 m in Salmon and Glacial lakes, 1994.

6. Macro-zooplankton density and biomass by sample date in Salmon Lake, 1995.

7. Macro-zooplankton density and biomass by sample date in Glacial Lake, 1995.

8. Map of Salmon Lake showing the distribution of rearing fish by density for the 26 September 1995 hydroacoustic survey.

9. Relative percent of rearing fish by depth stratum in Salmon Lake based on the 26 September 1995 hydroacoustic survey.

LIST OF APPENDICES

Appendix A: Results of analysis for elements in water samples collected from Salmon and Glacial lakes in 1994.

A. 1. ICP-MS analysis

Appendix B: Results of analysis for phytoplankton in water samples collected from Salmon and Glacial lakes in 1994.

B. 1. Phytoplankton density, volume, and carbon content for samples collected from station 1 at Salmon Lake, 1994.

B.2. Phytoplankton density, volume, and carbon content for samples collected from station 3 at Salmon Lake, 1994.

B.3. Phytoplankton density, volume, and carbon content for samples collected from station 1 at Glacial Lake, 1994.

B.4. Phytoplankton density, volume, and carbon content for samples collected from station 3 at Glacial Lake, 1994.

ABSTRACT

In 1994 and 1995 limnological and fisheries investigations were conducted on Salmon and Glacial lakes to assess sockeye salmon Oncorhynchus nerka rearing capacity and the potential to increase the run size of these stocks. Both lake systems were sampled for emigrating smolts; in Salmon Lake the smolt either migrated earlier than the time of gear deployment or avoided the trap, while a total of 13,485 sockeye salmon smolts were enumerated at Glacial Lake. An adult weir was installed in Pilgrim River, the outlet of Salmon Lake and resulted in a partial escapement count of 2,170. It is believed a portion of the sockeye salmon escapement entered the lake before the weir was fish proof as the aerial index count was over 6,000. Both lakes are ultra-oligotrophic as nutrient and chlorophyll a concentrations were low compared to other lakes supporting sockeye salmon. In 1995, when these lakes were sampled over the summer, a modest level of macro- zooplankton biomass was observed in Salmon Lake (250 mg/m2) and a lower level (100 rn@m2) was found in Glacial Lake. On a comparative basis of macro-zooplankton biomass in other Alaskan Ilursery.lakes. these two lakes appear to currently have a deficient number of sockeye salmon. Historical aerial survey estimates of sockeye salmon escapement in Salmon Lake have averaged 1,850 and in Glacial Lake the average has been 700. Based on the first 111 year of sampling in 1995, the zooplankton forage base indicates that both lakes could support additional numbers of rearing fry. However, the critical question is what level of additional sockeye salmon fry can these lakes support and simultaneously maintain zooplankton biomass at levels high enough to sustain an increase in production. Data collected in 1994 and 1995 are presented and discussed, and recomnendations are made concerning potential sockeye salmon production and improvements in sampling for 1996.

INTRODUCTION

Historically, Salmon and Glacial lakes supported large(r) populations of sockeye salmon Onorhynchus nerka; in the early 1900s ore cars for mining activities were filled with sockeye salrnon from Salmon Lake and brought back to Nome. Several written accounts from news articles mention large returns of spawning salmon available for dog focd. Verbal accounts from local residents living in the area reveal that many years ago ,$ll netting for sockeye salrnon was done in Salmon Lake, and they had numerous fish drying racks along the lake shore. The Salmon LakePilgrim River sockeye salmon stock was a traditional source of subsistence salmon for people living in Teller, Brevig Mission, Mary's Iglw, and Nome. The salmon were used for both human consumption and dog food

Since the early 1960s the Alaska Department of Fish and Game (ADF&G) has been concerned about the strength of the sockeye salmon populations in Salmon and Glacial lakes, particularly for the Salrnon CakePilgrim River system, and began monitoring the Port Clarence District subsistence sockeye salrnon harvest. In 1964 a permit was required for subsistence fishing, and subsistence fishing was prohibited in the Grand Central River, which is the main spawning tributary of Saltnon Lake. Additional restrictions were placed upon the Pilgrim River fishery prior to 1966, ancl the catch declined considerably; subsistence sockeye salmon harvests were 3,586 in 1963, 1,475 in 1964, 1,267 in 1965, and 130 in 1966 (Regart et al. 1966). Aerial surveys of Salmon Lake and the Grand Central River have been conducted since 1963, and the sockeye salmon subsistence harvest has also been monitored since 1963. A small commercial chum salmon (0. keta) fishery was conducted in the Port Clarence District in 1966. The commercial catch for all subdistricts in Norton Sound averaged 309 sockeye salmon for 1983- 1993 (Lean et al. 1995). Aerial surveys of Glacial Lake have been conducted since 1978.

In 1994 the ADF&G Division of Sport Fish conducted a fisheries survey on Salmon Lake to estimate fish species composition and mean gill.net catch-per-unit effort by species. A total of 309 fish were captured with variable mesh (five different mesh panels) gillnets, baited minnow traps, and hoop traps. The catch consisted of the following species (in order of magnitude of catch): ninespine stickleback Pungitius pungitius, round whitefish Prosopium cylindr-aceurn, least cisco Coregonus sardinella, slimy sculpin Cottus cognatus, Arctic grayling Thymallus arcticus, Dolly Varden Salvelinus malrna, sockeye salmon adults, coho salmon 0. kisutch fry, and burbot Lota iota (DeCicco 1995). Another fish specie previously documented in Sahnon lake is Arctic char Salvelinus alpinus, and anecdotal evidence suggests that the following species may have or do occur: northern pike Es0.u lucius, humpback whitefish Coregonus pidsciarr, lake trout Salvelinus nanzaycush, and Alaska blackfish Dallia pectoralis (DeCicco 1995). Some of these fish may compete with rearing juvenile sockeye salmon as the juvenile fish of the following species are know11 to graze on zooplankton (some only during their early juverlile life stage): ninespine stickleback, least cisco, coho salmon fry, northern pike, humpback whtefish, lake trout, and Alaska blackfish. Also pisciverous fish species preying on sockeye saltnon alevins and juveniles are: Dolly Varden, Arctic char, lake trout, burbot, coho salmon fry, and northern pike (Morrow 1980).

The sockeye sahnon investigations on Sabnon anti Glacial lakes was initiated in 1994 to determine the status of these two stocks relative to the potential for increasing production. In 1995, several agencies became involved with this project including the ADF&G, the U. S. Bureau of Land Management (BLM), the Bering Sea Fishermen's Association (BSFA) and KAWERAK Inc. Native Association. The project was developed to collect information on the sockeye salmon smolt

and adult populations of Salmon and Glacial lakes and to integrate this data with limnological parameters to assess lake rearing capacities. These studies will be continued through 1996 and will be used to determine if the rearing capacity of these lakes are being fully utilized, and the potential for increasing production through restoration/enhancement activities such as lake stocking, lake fertilization, and management actions.

Study Site Description

Both Salmon and Glacial Lakes are located on the Seward Peninsula, near Nome, Alaska (Figure 1). Salmon Lake (64" 54' N, 165" 00' W) is approximately 55 km northeast of Nome and is accessible via the Nome-Taylor road. Salmon lake has a volume of 95 x lo6 m3, a surface area of 7.49 km' (1,851 acres), a mean depth of 12.7 m, and a maximum depth of 40 m (Figure 2). Salmon Lake drains a watershed area of 209 km2 and is the headwater of the Pilgrim River, which drains into'Imuruk Basin. There are several tributary creeks draining into Salmon Lake, and the Grand Central River is the largest tributary. The land at the smolt sampling and adult weir sites are currently under the jurisdiction and management of the BLM, as is the majority of the watershed area around Salmon Lake. The land near the lake outlet has been selected for conveyance by the Bering Straits Native Corporation. Land immediately bordering Salmon Lake is owned by either the State of Alaska or by private individuals.

Glacial Lake (64" 52' N, 165" 42' W) is approximately 40 km norhwest of Nome and is accessible by air or off-road vehicle. Glacial Lake has a volume of 23 x lo6 m3, a surface area of 3.99 km' (986 acres), a mean depth of 5.8 m, and a maximum depth of 22 tn (Figure 3). Glacial Lake drains a watershed area of 49 km2 and drains into the Sinuk River which drains into the Bering Sea. The land around Glacial Lake and the outlet are under the jurisdiction and management of the BLM.

MATERIALS AND METHODS

Smolt Enumeration and Sampling

hl Salmon Lake, smolts were captured with the use of an inclined-plane trap (Todd 1994) placed in Pilgrim River approximately 3 krn below the lake outlet. The trap was installed on 7 June, and leads were placed to the north bank and 2 m towards the south bank. The leads were pulled on 09 June because of ice conditions in the river, and the trap was removed from the river during 16-2 1 June because of river ice. The trap was fished through 27 July 1995. All fish captured in the live- box were individually enumerated by species and released. At the smolt site, Pilgrim River is 43 In wide and the maximum depth is 1 m. The mean discharge from the lake during June-July was 18.1 1n3 /sec (639.5 ft3 /sec).

In Glacial Lake, srnolts were captured wid1 the use of a fyke net that fished 95% of the lake outlet width. The fyke was installed on 16 June and fished continuously through 24 July 1995. The net had leads extending from the east bank and to witlun 2-3 m of the west bank. At the smolt site the outlet is 37 m wide and the maximum depth is 1 m. The mean clischarge fonn the lake during June-July was 4.1 1n3 /sec (145.4 ft3/sec).

A random sample of up to 25 sockeye salmon smolts were sampled each day for size and age. After the peak emigration, smolts were sampled twice weekly. The smolts were anesthetized in a solution of MS-222 and measured for snout-to-fork len,@ (nearest millimeter) and weight (nearest

0.1 g). A scale smear was taken from the primary growth area and placed on a labeled glass slide for later aging with a microfiche scale reader. In addition, otolith were removed from 25 smolts per lake and processed for aging (Glick and Shields 1993) at the Soldotna ADF&G limnology laboratory to verify ages with corresponding scale samples.

Adult Enumeration and Sampling

An adult salmon weir was installed at the outlet of Salmon Lake on 15 July and operated through 22 August 1995. This was constructed of metal pickets, and to pass fish through the weir several pickets were removed. Three times weekly a random sample of 10 sockeye salmon were sampled for mid eye-to-fork len,@ (nearest 0.5 cm) and sex. Three scales were collected from the primary growth area of each sampled fish and placed on labeled , w e d cards. The gummed cards were later pressed onto acetate cards, and a microfiche scale reader was used to determine ages.

Limnological Surveys

In 1994 lirnnological surveys were conducted twice at each lake. Beginning in 1995, limnology surveys were conducted on both Salmon and Glacial Lakes once every 3-4 weeks beginning at ice out until prior to freeze-up. Two permanent sampling stations (buoys attached to lines anchored on the lake bottom) were placed in each lake in 1995 (Figures 2 and 3). An additional two zooplankton sampling sites were also sampled at each lake during 1994 and 1995. Chemical and biological sarnpIes were collected at each station and were analyzed according to procedures clescribed by Koenings (et al. 1987). Dissolved oxygen (D.0.) and temperature profiles (taken at 1-m intervals from the surface to 5 m, then at 5-m intervals to the bottom) were recorded at each station using a Yellow Springs hc.@ model-51B temperature/D.O. meter and probe. This instrument was calibrated each trip for D.O. by the Winkler titration method. The 1% incident light level (euphotic zone depth) was measured using an International Light Inc. model-IL1400A photometer and a submersible probe.

Water samples for nutrient and general water-quality analysis were taken at 1 m and 75% of the bottom depth at all stations. Water samples were pre-processed (filtered, preserved, and/or stored) at the Nome ADF&G laboratory for later analysis at the ADF&G linlnological laboratory in Soldotna. In aciciition, water samples for metal analysis were collected from both lakes in 1994 and preserveti with 0.5 ml of 1:l nitric acid solution. Analysis of metal samples was conducted by Elemental Research Inc. of Canada under a State of Alaska contract. Phytoplankton samples were collected and preserved with 2 ml of Lugol's acetate from two dates and two stations at a depth of 1 m in 1994 at both lakes for species identification and enumeration. Analysis of the phytoplankton samples was done by Eco-Logic Ltd. of Canada under a State of Alaska contract. Algal biomass (clllorophyll a) was processed on all water samples using procedures described by Koenings et al. (1987). Finally, zooplankton were collected with a 0.5-m diameter zooplankton net (153 ,um mesh). Vertical tows were taken from 1 m above the bottorn to the surface at each site, and samples were preserved in a 10% buffered formalin solution for latter analysis of species identification, enumeration and sizing, and computation of density and biomass by the ADF&G limnnology laboratory using procedures tiescribed by Koenings et al. (1987).

@Reference to cornmercial products or trade names does not constitute endorsement by ADFLkG.

HydroacousriclTownet Survey

A hydroacoustic survey was conducted at Salmon Lake on 26 September 1995 to estimate the number and distribution of sockeye salmon juveniles rearing in the lake. The hydroacoustic survey consisted of recording data along a total of 10 transects perpendicular to the longitudinal axis of the lake (Figure 2). The boat was operated at a speed of 2 m/sec. Seven transects were used to collect fish signals in the west (deeper) basin and three were used to record data in the east basin. Recording of down-looking acoustic data along the transects was done at night because juveniIe sockeye salmon are more dispersed during darkness. A BioSonics model- 105 echosounder system with a 6/15" dual-beam transducer was used for the survey. Fish signals were recorded electronically using a Sony model-TCD-Dl0 digital audio tape recording system, and on paper using a BioSonics model-115 chart recorder. Analysis of the recorded hydroacoustic tapes was conducted by Dr. Richard Thome of BioSonics Inc. under a State of Alaska contract.

Tow netting was conducted in conjunction with the hydroacoustic survey on 27 and 28 September 1995 to determine species of acoustically-counted fish, and to determine sizes and ages of juvenile sockeye salmon. Townetting procedures consisted of using a 2 x 2 m monofilament tow net pulled at a speed of approximately 0.7-1.5 m/sec. Tows were conducted with one boat on the night of 27 September and with two boats on the night of 28 September 1995. The tows were conducted at a depth of 15 m on both nights except for one tow conducted at 5 m on 27 September.

RESULTS

Smolt Abundance, Size, and Age

A total of 13,485 sockeye salmon and 309 coho salmon smolts were enumerated at Glacial Lake during 17 June-24 July 1995 (Table 1). Two peaks in the sockeye salmon smolt migration occurred; a first peak on 20 June and a second peak on 02 July (Table 1; Figure 4). The average sizes for sockeye smolts sampled in 1995 were 89 mrn and 5.9 g for age-1, 97 mm and 7.1 g for age-2, and 108 rnrn and 10.0 g for age-3 (Table 2). The migration comprised 44.3% age-l,48.5% age-2, and 7.2% age-3 smolts. Based on this age composition, an estimated 5,973 age-1, 6,543 age-2, and 969 age-3 sockeye salmon smolts emigrated in 1995. The age-3 smolts emigrated during the first 10 days, and the age- 1 srnolts comprised the majority of the emigration beginning 01 July (Figure 4). The coho salmon smolts emigrating Glacial Lake were not sampled for age, weight and len,m.

A total of only 155 sockeye salmon and 100 coho salmon smoIts were caught in the inclined-plane trap in the Pilgrim River (Salmon Lake) during 07 June-26 July 1995. The average sizes for sockeye smolts sampled in 1995 were 52 rnm and 1.2 g for age-0, 76 mm and 3.5 g for age-1, and 92 rlun and 5.6 g for age-2 (Table 3). The sampled age composition comprised of 4.3% age-0, 76.6% age-I, and 19.1 % age-2 smolts.

Adult Abundance, Size, and Age

A total of 2,170 sockeye salmon, 10 coho salmon and 22 chum salmon were enumerated at the Salmon Lake weir during 19 July-22 August 1995 (Table 4). The highest passage rates occurred between 1400 and 1530 11. The mean lengths of the major age classes of sockeye salmon sampled at Salmon Lake were 60 cm for age 1.3, 5 1 cm for age 2.2, and 60 cm for age 2.3 (Table 5). 'The

age composition of the returning adult sockeye salmon was 17.3% age 1.3, 12.3% age 2.2, and 66.7% age 2.3 fish.

In 1995, an aerial survey of Salmon Lake and the Grand Central River estimated 5,433 and 628 sockeye salmon, respectively (Table 6). The mean sockeye salmon escapement (from aerial surveys) since 1963 is 1,446 and 408 in Salmon Lake and Grand Central River, respectively (Lean et al. 1995). The mean sockeye salmon harvest of 9 16 is based on 22 years of available.data since 1963 (Table 6). The aerial survey of Glacial Lake in 1995 estimated a total of 733 sockeye salmon, which is similar to the mean of 707. In 1977, the only year in which a weir was used to count the escapement, a total of 545 sockeye salmon entered Glacial Lake (Pearson 1977).

Limnological Parameters

In 1994, lirnnological surveys were conducted twice (03-04 August and 27-28 September) at both Salmon and Glacial lakes. In 1995, limnological surveys were conducted five times (27 June, 13 and 23 July, 15 August and 27 September) at Salmon Lake, and three times (17 June, 11 July and 19 August) at Glacial Lake.

Summaries of lirmological parameters sampled for Salmon and Glacial lakes, and comparison to mean values for 57 other dear-water lakes containing sockeye sahnon in Alaska are presented in Tables 7 anci 8, respectively.

Light Penetration. Temperature, and Dissolved Oxvgen

Both lakes are very clear as the euphotic zone depth extended to the bottom of Glacial Lake and to 28 m or 70% of the maximum depth in Salmon Lake. There was little turbidity (<1 NTU) in these lakes, and color averaged about 5 Pt units, indicating that these systems are clear-water lakes.

In August, Salrnon Lake was thermally stratified (a thermocline was present at about 15 m), while Glacial Lake was not. In Salmon Lake, the August surface temperature was about 12" C and in Glacial Lake was about 1 1" C. In late September both lakes were isothernlal.

The seasonal mean water column temperature was slightly higher (about 1" C for the average of both stations) in Glacial Lake than in Salrnon Lake. The initiation of heating (when the lake temperature at 1 m was at or greater than 4" C) was slightly earlier in Glacial Lake and the rearing duration (days when the lake was above 4" C) in Salmon Lake was slightly longer, presumably due to the larger size of Salmon Lake.

The D.O. concentrations in the surface water of both lakes was about 11.5 m a or 100% saturation. In contrast, near the bottom of Salmon Lake, the D.O. concentration was 8.8 rngL or about 70% saturation, while hl Glacial Lake the D.O. concentration near the bottom was about the same as the surface or 100% saturated.

General Water Chemistw

Glacial lake has a pH value slightly lower than neutral while Salmon Lake had a pH value slightly above. The alkalinity and conductivity was substantially higher in Salmon Lake. The higher concluctivity in Salmon Lake indicates an increased level of dissolved material, and specifically indcates a higher potential of nutrient availability. Calcium and magnesium are two important

elements as micro-nutrients for normal metabolism of higher plants, and contribute to water hardness. In Salmon Lake, calcium and magnesium concentrations were much higher than in Glacial Lake, and much higher than other clear-water sockeye nursery lakes. Iron is an essential element for phytoplankton and in both lakes the concentration was quite similar; also, on average, the iron concentration in these two lakes was slightly lower than in other sockeye salmon nursery lakes. Of the four water samples per lake that were sent in for a metal scan (Appendix A), none of the critical metals exceeded the Environmental Protection Agency standards for aquatic organisms (toxicity) or for drinking water.

Nutrients

Total phosphorus (TP) is generally considered the primary nutrient limiting production in lakes. The mean TP concentrations within the epilirnnion (1 m) of Salmon Lake ranged frorn 1.7-3.1 p&. A IGgh mean of 5.4 p a in Salmon Lake was observed in the hypolimnion (27 m) in 1994. This higher mean could be from decomposing plant material. In Glacial Lake, the mean TP in the epilimnion ranged slightly higher at 2.3-3.2 p&. Both lakes are considered ultra-oligotrophic (TP <3 pa), and suffer from the lack of available phosphorus for higher trophic production. In addition, the mean values for the inorganic fractions of nitrogen (ammonia and nitrate) were with few exceptions below the detection limits, indicating that available inorganic nitrogen is quickly assimilated and in high demand by phytoplankton.

Phytoplankton

Mean algal biomass (as indicated by chl a levels) in the epilimnion of Salmon Lake ranged from 0.58-0.95 p&, and in Glacial Lake from 1.05-1.54 p@. These levels are lower than the mean for 57 other Iakes in Alaska that contain sockeye salmon.

Phytoplankton density, volume, and carbon content by taxa for the two dates samplecl in 1994 for both lakes are presented in Appendix B. The edible phytoplankton (useable for food by zooplankton), particularly the chyrso-cryptophtyes and other miscellaneous taxa, in both lakes were observed in higher densities than the non-edible forms (Figure 5). Overall, the samples analyzed in 1994 indicated few inedible taxa of phytoplankton, and many of the species were rated prime food for zooplankton (Appendix B). Thus, although algal biomass in these lakes was lower than other sockeye salmon nursery lakes, most of the phytoplankton taxa appears to be edible by zooplankton.

Zooplankton

In S d n o n Lake, Cyclops and Bosmina were the most abundant taxa within the macro-zooplankton community, followed by Daphnia (Table 9). Cyclops were over twice as abundant as Bosmincr (88,000/m2 compared to 34,500/m2) in 1995. In 1994, these two taxa were equally abundant but sarrlpling in 1994 was limited to August and September only. The mean macro-zooplankton ciensity and biomass for all four stations in 1995 was 150,000/1n' and 245 1ng/m2, respectively. The peak density and biomass for Cyclops occurred in late July wllile that for Bosmina and Daphnin occurred in late September (Figure 6). In Glacial Lake, the macro-zooplankton community comprised ~nainly of Bosmina and Diaptomus in near-equal density, followed by Cyclops (Table 10). The mean macro-zooplankton density and biomass for all four stations averaged 58,500/m2 and 107 mg/m2, respectively. Of the tluee dates sunpled for zooplankton in Glacial Lake, the peak density and biomass for Bosmina occurred on 19 August, whereas for

Diaptomus the peak density occurred on the 19 August sample date and the peak biomass occurred on 11 July (Figure 7). The macro-zooplankton density and biomass in Salmon Lake is about 2.0- 2.5 times hgher than in Glacial Lake, and Salmon Lake contained a higher density of cladocerans (Daphnia and Bosmina), which are preferred prey of sockeye salmon fry.

Salmon Lake Hydroacoustic Estimatt. of Rearing Fish

Based on the hydroacoustic survey conducted on 26 September 1995, an estimated 2.3 f 0.9 million fish were rearing in Salmon Lake (Table 11). The majority of the rearing fish (1.8 million) were in the west (deeper) basin of the lake. Transect 7, which is located in the west basin (Figure 2), was included in the east basin for the population estimate because the bottom morphology is similar to the east basin; flat gradient near shore and a shallow bottom. The central area of transect 3 and the northern third of transect 4 had the highest fish densities of 858 and 825 fish/1,000 m', respectively (Figure 8). The highest relative percent of rearing fish was observed in the 9- 13.5 m depth stratum in both basins of the lake (Figure 9).

A total of 8 mid-water net tows were conducted on the nights of 27 and 28 September 1995 for a total of 3 hours and 53 minutes in an effort to collect sockeye salmon fry. Only 4 sockeye salmon fry were captured for all the tows, and no other fish were caught.

DISCUSSION

A comparison of macro-zooplankton density, biomass, and mean escapements in 20 sockeye nursery lakes in Alaska (Table 12) suggests that the runs at Salmon and Glacial lakes are depressed and the rearing capacity may not be fully utilized. All the other lakes beside Salmon and Glacial lakes have substantial higher sockeye salmon escapements. Thus, it would be easy to make the assumption that the Nome lakes could support and produce similar numbers of sockeye salmon in lakes with similar levels of zooplankton biomass. However, because the Nome lakes are at the most northern limit for sockeye salmon, are ultra-oligotrophic (very low nutrients), and have a short rearing season, extrapolation of production from other lakes to these lakes is risky.

If we assume these lakes can maintain a zooplankton biomass at an average level of 100 mam' for Glacier Lake and 250 mgm' for Salmon Lake, the following would be an estimate of sockeye salmon production based on the zooplankton-smolt biornass model of Koenings and Kyle (1996):

1 1 100 mg/m2 would yield 210 kg of smolts per km' and 250 mgm' would yield 525 kg of s~nolts per km'

2) 210 kgAa11' would yield 168,000 5 g (optimum size relative to marine survival) s~nolts for Glacier Lake, and 525 kg/lun2would yield 786,000 5 g smolts for Salmon Lake

3) assuming 12% smolt-to-adult survival, a total adult return of 20,000 for Glacial Lake and 95,000 for Salmon Lake would be estimated.

However, the critical question is whether these lakes can rear adclitional sockeye salmon fry to produce these levels of smolt and adults on a sustainable basis, and simultaneously maintain the zooplankton hiomass at the above assumed levels. These lakes nlay deviate from the average lake assumed in the zooplankton-smolt bionlass model due to their high degree of oligotrophy, short

growing season, or unique early life history traits. Consequently, the initial goal for smolt and adult production should be 50% of the modeled one for each lake. Thus, the initial goal for Glacial Lake would be to produce 10,000 adult sockeye salmon from 84,000 smolts, and for Salmon Lake to produce 48,000 adult sockeye salmon from 393,000 smolts.

RECOMMENDATIONS

For 1996, the following changes and additions are recommended:

1) In Glacial Lake the fyke net should be installed earlier, immediately after ice out. The smolt gear will need to be freighted in by snow machine or helicopter and stored on site, and the crew will either hike in or be flown in by helicopter at the appropriate time. The fyke net lead in Glacier Lake on the west bank should be configured to allow passage of returning adult salmon. It might be possible to set a passing chute to allow for a partial adult enumeration, until the fyke net and camp are pulled for the season.

2) Another inclined-plane trap should be used in Salmon Lake, and the two traps should be moved to a different site than the one used in 1995 to increase the catch of smolts. The water is very clear in the Pilgrim River, and with continual daylight, trap avoidance may continue to be a problem. In addition, longer leads should be used in 1996 to increase the catch efficiency.

3) The adult salmon weir at Salmon Lake was not in place before the first adults showed up at the lake in 1995 for several reasons. In 1996, the weir needs to be in place and fish tight by the first of July to get a total enumeration. In addition, approximately 5 m more weir material is needed for 1996, and the sampling number of adults for age and size data needs to be increased. Additional sampling of adults should include genetics, pathology, and fecundity, and surveys for potential in-stream incubator sites should be done.

4) The hydroacoustic survey conducted in 1995 indicated a relatively high number of rearing fish in the lake compared to the low sockeye salmon escapements. The low net catches revealed that, like in many clear-water lakes, net avoidance is a problem. During the spring of 1996 we recommend extensive trawling using a larger net (2 x 7 m) that has been shown to increase catch efficiency in other clear-water lakes. This would provide apportionment of rearing fish by species and the collection of fish species that may compete with sockeye salmon fry. In addition, in 1996 if another hydroacoustic survey is done, the transects need to be modified, such that they are broken into three distinct areas in order to lower the 95% confidence interval within the 20% range.

5 ) Limnological sampling should continue in 1996 to provide a more complete data set to estimate standing stock of zooplankton, the potential rearing capacity, and enhancement options.

LITERATURE CITED

DeCicco, A. I Lake, Fish,

,. 1995. Assessment of Arctic Grayling in selected streams and a survey of Salmon Seward Peninsula, 1994. Alaska Department of Fish and Game, Division of Sport Research and Technical Services. Fishery Data Series No. 95-19. Anchorage,

Alaska.

Glick, W. J., and P. A. Shields. 1993. Juvenile salmonid otolith extraction and preparation techniques for microscopic endia t ion . Alaska Department of Fish and Game, Division of Commercial Fisheries Management and Development, FRED Division Report Series No. 132. Juneau, Alaska.

Koenings, J.P., and G.B. Kyle. 1996. Collapsed populations and delayed recovery of zooplankton in response to heavy juvenile sockeye (Oncorhynchus nerka) foraging. Proceedings of the international symposium on biological interactions of enhanced and wild salmonids. Special Publication of the Canadian Journal of Fisheries and Aquatic Sciences. In review.

Koenings, J. P., J. A. Edmundson, G. B. Kyle, and J. M. Edmundson. 1987. Lirnnological field and laboratory manual: methods for assessing aquatic production. Alaska Department of Fish and Game, FRED Division report Series No. 71. Juneau, Alaska.

Lean, C. F., F. J. Bue, and T. L. Lingnau. 1995. Norton Sound-Port Clarence-Kotzebue 1993 Annual Management Report. Alaska Department of Fish and Game, Division of Conunercial Fisheries Management and Development. Regional Irlformation Report Series No. 3A95-06. Anchorage, Alaska.

Morrow, J. E. 1980. The freshwater fishes of Alaska. Alaska Northwest Publishing Company. Anchorage, Alaska.

Pearson, T. 1977. Glacial Lake development project: a study to determine the feasibility of developing a red salmon population in Glacial Lake. Unpublished technical data report.

Regnart, R. I., R. Baxter, M. F. Geiger, A. Jackson, J. Dean, and H. Danielsen. 1966. Arctic- Yukon-Kuskokwirn 1966 Annual Report. Alaska Depamnent of Fish and Game, Division of Commercial Fisheries, Section I Management. pp. 86-9 1. Anchorage, Alaska.

Todd, G. L. 1994. A lightweight, inclined-plane trap for sampling salmon smolts in rivers. Alaska Fishery Research Bulletin l(2): 168- 175.

Table 1. Daily migration of sockeye salmon smolts from Glacial Lake, 1995.

Accum. Accum. Date Sockeye sockeye Coho coho

7/24 9 13,485 0 309 Total 13,485 309

Table 2. Population estimate, size, and age of Glacial Lake sockeye salmon smolts by sample period, 1995.

Mean Mean Sample Age Population Sample Age length weight period class estimate size comp. (mm) S .D. (9) S.D.

17 - 20 Jun 2 1,442 73 73% 98 3.3 7.2 0.9 3 533 27 27% 108 5.3 10.1 1.6

21 - 24 Jun 1 159 6 6% 84 4.8 4.4 0.7 2 2,147 8 1 81 % 98 4.4 7.4 1.1 3 345 13 13% 110 5.7 10.5 2.2

25 - 28 Jun 1 544 24 24% 84 4.5 4.7 0.8 2 1,632 72 72% 96 3.5 6.9 0.9 3 9 1 4 4% 98 3.4 7.2 1 .I

29 Jun - 2 Jul 1 1,728 59 59% 86 5.2 5 .O 1.0 2 1,201 4 1 41% 96 4.6 6.7 1 .I

Weighted means Age 1 5,973 391 44.3% 89 0.3 5.7 0.1

95% C.I. + 372 Age 2 6,543 279 48.5% 97 0.2 7.1 0.1

95% C.I. + 445 Age 3 969 44 7.2% 108 0.8 10.0 0.3

95% C.I. + 261

Table 3. Size and age of Salmon Lake sockeye salmon smolts, 1995.

Mean Mean Sample Sample Age Age length weight period size class comp. (mm) S.D. (g) S.D.

Table 4. Daily migration of sockeye salmon adults for Salmon Lake, 1995.

Accum. Accum. Accum. Date Sockeye sockeye Coho coho Chum chum

250 - Estimated before weir was fish tight. 711 9 189 439 0 0 0 0 7/20 78 51 7 0 0 0 0 7/21 53 570 1 1 0 0 7/22 204 774 0 1 0 0 7/23 53 827 0 1 0 0 7/24 76 903 0 1 0 0 7/25 89 992 0 1 0 0 7/26 102 1,094 0 1 0 0 7/27 59 1,153 1 2 0 0 7/28 65 1,218 0 2 2 2 7/29 48 .1,266 0 2 1 3 713 0 151 1,417 0 2 2 5 713 1 11 1,428 0 2 0 5 81 1 68 1,496 0 2 0 5 812 32 1,528 0 2 1 6 813 89 1,617 0 2 1 7 814 27 1,644 0 2 0 7 815 17 1,661 0 2 1 8 816 40 1,701 0 2 2 10 817 48 1,749 0 2 4 14 818 61 1,810 0 2 4 18 819 39 1,849 0 2 0 18 811 0 34 1,883 0 2 0 18 811 1 38 1,921 0 2 0 18 811 2 41 1,962 0 2 1 19 811 3 12 1,974 0 2 1 20 811 4 25 1,999 0 2 0 20 811 5 21 2,020 0 2 0 20 811 6 35 2,055 0 2 1 2 1 811 7 17 2,072 0 2 I 22 811 8 26 2,098 0 2 0 22 811 9 13 2,111 0 2 0 22 8/20 11 2,122 0 2 0 22 8/21 28 2,150 3 5 0 22 8/22 20 2,170 5 10 0 22 Total 2.170 10 22

Table 5. Mean length and age composition of adult sockeye salmon sampled at Salmon Lake, 1995.

Mean Age Sample length class size" (c m) S.D. Comp.

Male 45 Female 29

- -- -

11 Seven fish were not sexed.

Table 6. Aerial survey estimates of sockeye salmon in the Salmon Lake system and in Glacial Lake, and the harvest of sockeye salmon destined for Salmon Lake in the Port Clarence Destrict, 1963-1995.

port Salmon Lake system Clarence

Sa lmn Grand Central Glacial sockeye Year Lake River Total Lake harvest

1963

1964 " 1965

1966

1967

1968

1969

1970

1971

1972

1973 " 1974

1975

1976

1977 1978

1979

1980

1981 I/

1982 l1

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995 Mean

l1 No aerial survey or subsistence survey conducted. 2 Poor survey. 31 Boat Suwey. 41 Species composition estimated at 10% sockeye salmon. " Weir count. 61 Data collected from a low number of returned catch surveys; catches are

incomplete and not comparable. Survey conducted by Subsistence Division.

Table 7. Summary of limnological parameters (seasonal means by year, station, and depth) for Salmon Lake, 1994-1995.

Station 1 Station 3 Year/ 1994 1995 1994 1995 1994 1995 1994 1995 Mean values

Depth (m)/ 1 1 27 3 1 1 1 15 15 clear lakes1'

Seasonal mean water column temp. ("C) Date of initial heating (1 m water at 4' C) Seasonal heat budget (g-cal/cm2) Rearing duration (days above 4OC @ 1 m)

Parameter Conductivity (pmhos/cm) pH (units) Alkalinity (mg/L) Turbidity (NTU) Color (Pt units)

Calcium (mg/L) Magnesium (mg1L) Iron (pg/L)

TKN (CIg/L) Ammonia (pg1L) Nitrate (pg/L)

Silica (vg/L) 1,955 1,902 2,000 2,284 1,948 1,925 2,020 2,000 1,722

Chl-a (pg1L) Phaeo (pg1L)

11 Mean values for 57 clear-water lakes in Alaska that contain sockeye salmon. DL indicates detection limits.

Table 8. Summary of lirnnological parameters (seasonal means by year, station, and depth) for Glacial Lake, 1994-1 995.

Station 1 Station 2 1994 1995 1994 1995 1994 1995 1994 1995 Mean values

Depth (m)/ 1 1 12 12 1 t 15 15 clear lakes1'

Seasonal mean water column temp. (" C) Date of initial heating (1 m water at 4" C) Seasonal heat budget (g-cal/cm2) Rearing duration (days above 4 O C @ 1 m)

Parameter Conductivity (pmhoslcm) pH (units) Alkalinity (mg/L) Turbidity (NTU) Color (Pt units)

Calcium (mg/L) Magnesium (mg/L) Iron (pg/L)

TKN (cIsJL) Ammonia (pg/L) Nitrate (pg/L)

Silica (pg/L) 1,926 2,151 1,930 2,205 1,955 2,115 1,917 2,126 1,722

Chi-a (pg/L) Phaeo (pg/L)

11 Mean values for 57 clear-water lakes in Alaska that contain sockeye salmon. DL indicates detection limits.

Table 9. Summary of seasonal mean rnacro-zooplankton density and biomass in Salmon Lake, 1994-1995.

Taxa Station 1 Station 2 Station 3 Station 4 Mean of all stations

1994 1995 1994 1995 1994 1995 1994 1995 1994 1995

Density (no.Im2) Cyclops 52,555 78,149 68,434 121,802 19,078 67,007 23,874 84,667 40,985 87,906 Ovigerous Cyclops 4,160 3,827 0 10,936 P 1,111 P 798 2,080 4,168 Bosmina 54,170 25,634 62,455 50,257 34,861 19,233 17,507 42,860 42,248 34,496 Ovigerous Bosmina 13,160 1,440 11,598 3,328 5,876 2,927 5,706 16,217 9,085 5,978 Daphnia 15,962 9,869 35,439 23,603 6,410 4,649 3,040 9,798 15,213 11,980 Ovigerous Daphnia 3,142 5,118 4,526 5,651 917 8,490 153 2,666 2,185 5,481 Holopedium 340 0 0 0 0 0 0 0 8 5 0

Biomass (mgIm2) Cyclops 155.1 136.1 196.7 236.0 48.3 108.8 55.4 115.2 113.9 149.0 Ovigerous Cyclops 23.7 21.3 0.0 60.5 0.0 5.9 P 4.5 7.9 23.1 Bosmina 65.6 24.8 81.7 53.9 37.7 17.2 20.9 37.5 51.5 33.4

)--. 03 Ovigerous Bosmina 19.4 2.1 5.6 4.3 8.7 4.3 8.0 21.2 10.4 8.0

Daphnia 34.1 14.0 79.2 29.8 12.7 7.6 4.5 12.5 32.6 16.0 Ovigerous Daphnia 8.5 13.7 12.5 14.6 2.5 27.5 0.3 8.3 6.0 16.0 Holopedium 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0

P indicates organism is present but in very low densities.

Table 10. Summary of seasonal mean macro-zooplankton density and biomass in Glacial Lake, 1994-1 995.

Station 1 Station 2 Station 3 Station 4 Mean of all stations Taxa 1994 1995 1994 1995 1994 1995 1994 1995 1994 1995

Density (no./m2) Diaptomus Ovigerous Diaptomus Cyclops Ovigerous Cyclops Bosmina Ovigerous Bosmina Daphnia Ovigerous Daphnia Holopedium Ovigerous Holopedium Chydorinae Ovigerous Chydorinae

C-l LD im Calanoids

Ergasilus

Biomass (mg/rn2) Diaptomus Ovigerous Diaptomus Cyclops Ovigerous Cyclops Bosmina Ovigerous Bosmina Daphnia Ovigerous Daphnia Holopedium Ovigerous Holopedium Chydorinae Ovigerous Chydorinae im Calanoids Ergasilus

Table 11. Densities and population estimates of juvenile fish rearing in Salmon Lake by transect based on the 26 September 1995 hydroacoustic survey.

Weighted mean fish

Fish Area density Tran- density (X 1 o3 m2) (no11 000 Transect Basin sect1' (no.11000 m2) transect total m2) abundance abundance Variance

Basin A 179 179 539 130.1 1 574,558 181

6-N 397.85 229 6-C 560.04 229 687 448.69 1,981,415 6-S 388.1 8 229

Total 4.41 6

Basin B 7-S 0.00 152 7-C 0.00 152 458 30.80 94,720 7-N 91.61 154

10-N 94.1 1 263 10-C 77.62 263 789 58.62 180,267 10-S 4.1 4 263

Total 3.075

Total 9,182.98 7,491 Total 2,262,554 1.1 5E+11 S.E. = 338,478

95% confidence interval (+I-) = 870,084 t = 2.571

"S = southern third. C =center third, and N = northern third of transect.

Table 12. Seasonal mean macro-zooplankton density and biomass for 20 sockeye salmon nursery lakes in Alaska, showing the relative comparison for Salmon and Glacial lakes.

Lake and geographical Mean Density Biomass location" Escapement (no./m2) (mg/m2)

Chenik (CI) 10,000 872,000 2,223 Hidden (CI) 25,000 61 9,000 2,331 Chilkat (NSE) 68,400 646,000 1,287 Karluk (Kodiak) 650,000 520,000 1,041 Eshamy (PWS) 30,000 439,600 972 Packers (CI) 20,000 178,000 61 7 Skilak (CI) 800,000 230,000 556 Hugh-Smith (SSE) 17,500 290,000 523 McDonald (SSE) 98,700 91,000 297 Salmon (Nome) (2,000 150,000 250 Afognak (Kodiak) 65,000 143,000 185 Redoubt (NSE) 21 ,I 00 137,000 159 Frazer (Kodiak) 200,000 1 14,000 155 Chilkoot (NSE) 79,600 88,000 145 Upper Malina (Kodiak) 7,500 40,000 123 Glacial (Nome) <1 ,000 58,500 107 Tustumena (CI) 235,000 41,000 105 Coghill (PWS) 10,000 48,000 79 English Bay (CI) 5,000 54,000 56 Portage (Kodiak) 6,200 25,000 3 0 11 CI = Cook Inlet; PWS = Prince William Sound; NSE = Northern Southeast; SSE = Southern Southeast Alaska

Figure 1. Map of the Nome area (Seward Peninsula) showing the location of Salmon and Glacial lakes, a n d the Pilgrim River.

Grand ) Central River

.5 0 l k m 5 - - C_d

SALMON LAKE - NOME

Volume - 95 x 106m3

6 2 Surface area - 7.49 x 10 m

Mean depth - 12.7m

Maximun depth - 40m

(bottom contour in meters1

F i g u r e 2. Map o f Salmon Lake showing genera l morphometr ic i n f o r m a t i o n , and t h e l o c a t i o n s of t h e l i m n o l o g i c a l s u r v e y s t a t i o n s and hydro- a c o u s t i c t r a n s e c t s .

tJ Outlet

Figure 3 . Map of G l a c i a l Lake showing genera l morphometric i n f o r m a t i o n , and l o c a t i o n s of t h e l imnolog ica l su rvey s t a t i o n s .

EZIL

6 CIL

L 11L -

(d

.- 0 (d

-

s CIL 0

L

.- E CIL

C

!!? m

.- 1 CIL

E

al

L

LIL 0

c

tn L

-

m

(d

m

0

SlL al %

al Y

EIL

0 0

cn

SALMON LAKE 3.500

0

Diatom ChrysJCrypt Others Diatom ChrysJCrypt Others 8/4/94 9/27/94

GLACIAL LAKE 6,000

Y

-

-

-

-

-

-

0

Diatom CluysICrypt Others Diatom CllrysJCrypt Others 8/3/94 9/26/94

I I I

Figure 5. Mean density of edible and non-edible phytoplankton at 1 m in Salmon and Glacial lakes, 1994.

- El Edible Non-edible

-

-

-

-

- - -

I

-

Edible Non-edible

-

7

Grand { Central R ~ v e r

SALMON LAKE - NOME

Volume - 95 x 1 0 ~ ~ ~

6 2 Surface area - 7.49 x 10 m

Mean depth - 12.7m

Maximun depth - 4 0 m

(bottom contour in meters)

601-750

@ 451-600

Figure 8. Map of Salmon Lake showing the d i s t r i b u t i o n of rear ing f i s h by densi ty f o r the 26 September 1995 hydroacoustic survey.

APPENDIX A. Results of analysis for elements in water samples collected from Salmon and Glacial lakes in 1994.

- - - - - - - *-tar w..t bpt.nd.

.- - -4'' * tau3 Norrh Vnooum, RC. . Cnd. V7M 1 A5 - Dept. of A.)r & O m S t m H 2 S Kdfmdcy B..oh, W d o t ~ . A& USA- s@829

Td (W 98- Attn.Jhr- . - . Foc O8bOO71

. 1 _.-- .. Resub ue in micrograms per We (ppb) - : - . - --

- ELMaCl ~luirl-war stn 1 8/3/91 1. ~ l u f r l - M - stn 1 9/27/94 1. ~luirl-Wo& ~ t n 2 a m % 18

L i t h i u 1 .50 1.47 1.54 B e y l l i u 4 .SO 4 .SO 4.50 Boron <1 -0 <1 -0 <l .O

Miobiu 0.0500 4.030 0.0100 b l w 0.260 0.290 0.230 Ruthmiu 0.0500 4.W

. Y ~ . W & F % $ W . % . ~ ~ . p ~ ~ ~ g ; 3 ~ y f l x ~ 4.010

W f M * ....... && -&$%#m$T!3 s r tvtr"' 4.020 4.070 P ~ l l d i u 4.050 - .. 4.050 . . . 0,110 kQiu 4.050 4.050 , . .. 4.050 Tin 4.060 0.150 4.060

Ytterbiu 4.050 4.050 0.0800 Lutttiu 4.020 4.020 4.020 k f n i u 4.050 4.050 0.100

Rheniu 4 . N O 4.040 4.W OIIliu <0.030 9.030 4.030 I r id im 4.020 0.0300 0.0300

l h a l l i k L e d

,)$W.wr, a*---. r - - - - r r - ...,. ... -. e W r 1 V 8 3 WWJM9 a -267 west Lpluud. Apr 3 1895

North vrroocmr, B.C. Cwd.WM 1AS - O.Ot. of Fish & Cirri Str.844828 KSfwwky Boeuh, Sddobu, AK, USA. 8862s

Td (W 98- A t t ~ ~ J L n E h u d w n Fax 0864071

, f Resuits m in mlcrognms per 1 ' i (ppb) -, -* . I , _ . 1

3an' 6luirl-Nor Stn 2 9R7/% l a k l r x r ~ o r Stn 1 8/4/94 l a klm-lor ttn 1 9m194 l a :him 1.7s 2.24 1 .% yi l iu 4.50 4.50 4.50 .m el -0 <I -0 *1 .o

1c 9.48 4 -69 7.00 !ti- 0.0800 0.om 4.050 m i rn 4.10 4.10 0.210 ~ ~ ~ ~ ~ ~ ~ ~ ~ @ f g ~ q ~ ~ ~ $ ~ g @ ~ g ~ ~ j ~ ~ > ~ ~ $ ~ g ~ ~ ~ ~ & g ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ # ~ ~ ~ ~ ~ ~ ; ~ ~ ~ ~ ~ < ~ ~ ~ { ~ ~ ; ~ ; ~ g ~ $ <, mrr*CXX m,*r*s*r*sr*sm ...,...,r*s..,r*sr*s * ..,.r*sr*sr*s.r*sr*s.r*s.r*s" ..,.".-,.r*s....r*sr*s, A .r*sr*s. m.ax+i'- .....,,,,,- mine <id <ib

-.- -'-.. ---.. ..----. --.-. . \ , , vC"U "\ 8 % . A. l b r 7 V 1 3 W IWYSIS *rmI --267 Wost E8p&node Apr 3 189%-

~ v-, KC. of Asherie Crud. YIM 1AS k h ~ S t r B U I U P ~ 8 ~ Buh $ddo t~ , U USA. 9862S Td (604) 9860245 Ann.JimMmffd.on 'Fax S860071

, - 4 . Resutts a n in microgram perd' i (ppb) -

ELDENT k l m m - N o r Stn 3 8/4/94 1. klm-llar S t n 3 9/28f9b -1. L i t h i u 2.36 2.27 Beryl liu 4.50 9 .50 60r0cl *1 .O 4 . 0 km#iu 3870 3890

zi& . . 1 .bb .10.'8 Gal 1 f u 4.OSO 4.010 Garwnlu 4.10 4 .10 f i ~ : e ~ ~ ~ ~ . ~ ~ . ~ ~ ~ ~ ~ : ~ $ ; g g ~ j ~ ~ ~ & q ~ ~ , ~ ~ ~ ~ ~ ~ ~ ~ ~ , ~ ~ ~ ~ ~ ~ ~ q g + ~ ~ ~ ~ ; ~ ~ ~ g ~ ; ~ ~ j ~ ~ ~ . ...... .... ....... . . . u , , . . . ~ ~ ~ ~ . . ~

+A&+&&..,,. ~ - ~ < Q L c ' ~ ~ Y . . . . .iiii- B r o l i n *id <I 0 Selcniu <I .o <I .o Rhfd i r r . 1.41 1.34 S t r m t l u 57.1 55.1

I o d i n c..rfu b r i m

Yt t r rb iu 4.050 0~0900 Lutetium 9.020 4.020 Hafniu 4.050 0.0900

VIQStM

f h r l l i k L e d

APPENDIX B. Results of analysis for phytoplankton in water samples collected from Salmon and Glacial lakes in 1994.

Appendix 8.1. Phytoplankton density, volume, and carbon content for samples collected from station 1 at Salmon Lake, 1994.

Rating as Density Carbon Sample food source (no.cells/m3 Volume (pg c/m3

11 date for zoop. Group Species x 1 06) (mm3/m3) X 1 03)

8/4/94 E Diatom Achnanthes minutissima 51 .OO E Diatom Achnanthes lanceolata 25.50 e Diatom Cocconeis placentula 25.50 E Diatom Cyclotella sp2 76.50 E Diatom Cyclotella stelligera 153.00 e Diatom Fragilaria construens varl 51 .OO N Diatom Stephanodiscus astrea var3 25.50 N Diatom Synedra sp2 51 .OO E+ Chrysophyte Chromulina spl 765.00 E+ Chrysophyte Chrysochromulina sp. 943.50 E Chrysophyte Dinobryon cell sp l 51 .OO E+ Chrysophyte Dinobryon lorica spl 76.50 E+ Other Flagellate sp5 25.50 e Other Peridinium sp2 204.00 E+ Other Rhodomonos sp. 255.00 E+ Microalgae microflagellates 1,020.00 E Microalgae picoplankton 1,530.00

9/27/94 E Diatom Achnanthes minutissima 107.1 0 E Diatom Cyclotella sp2 21 4.20 E Diatom Cyclotella stelligera 142.80 e Diatom Fragilaria crotonensis varl 71.40

Diatom Hannea arcus 35.70 N Diatom Rhizosolenia sp. 285.60 N Diatom Stephanodiscus astrea var3 142.80 E+ Chrysophyte Chromulina spl 285.60 E+ Chrysophyte Chrysochromulina sp. 464.1 0 E+ Chrysophyte Cryptomonas sp5 35.70 E Chrysophyte Dinobryon cell spl 71.40 E+ Chrysophyte Dinobryon lorica spl 107.1 0 E Chrysophyte Mallomonas sp5 35.70 N Cyanophyte Oscillatoria sp2 999.60 E+ Other Chroomonas acuta 107.1 0 N Other Gymnodinium spl 35.70 N Other Gymnodinium sp5 35.70 e Other Peridinium sp2 178.50 E+ Other Rhodomonos sp. 107.1 0 E+ Other Scenedesmus spl 35.70 E+ Microalgae microflagellates 1,356.60 E M icroalgae picoplankton 2,142.00

11 E+ = prime, E = edible, e = not preferred but edible, and N = not edible.

Appendix 8.2. Phytoplankton density, volume, and carbon content for samples collected from station 3 at Salmon Lake, 1994.

Rating as Density Carbon Sample food source (no.cells/m3 Volume (pg c/m3

11 date for zoop. Group Species x 1 06) (mm3/m3) X 1 03)

8/4/94 E Diatom Achnanthes minutissima 59.50 E Diatom Achnanthes lanceolata 39.67 e Diatom Asterionella formosa 19.83 e Diatom Cocconeis placentula 19.83 E Diatom Cyclotella sp2 59.50 E Diatom Cyclotella stelligera 1 19.00 e Diatom Diatoma elongatum varl 19.83 e Diatom Fragilaria constmens varl 59.50 N , Diatom Stephanodiscus astrea var3 19.83 N Diatom Synedra sp2 39.67 E+ Chrysophyte Chromulina spl 436.33 E+ Chrysophyte Chrysochromulina sp. 595.00 E+ Chrysophyte Cryptomonas spl 19.83 E Chrysophyte Dinobryon cell spl 99.17 E+ Chrysophyte Dinobryon lorica spl 79.33 E Other Bitrichia ollula 39.67 E+ Other Flagellate sp5 99.1 7 e Other Peridinium sp2 99.17 E+ Other Rhodomonos sp. 11 9.00 E+ Microalgae microflagellates 892.50 E Microalgae picoplankton 1,090.83

9/27/94 E Diatom Achnanthes minutissima 29.75 E Diatom Cyclotella sp2 1 19.00 E Diatom Cyclotella stelligera 208.25 e Diatom Fragilaria constmens varl 89.25 N Diatom Rhizosolenia sp. 357.00 N Diatom Stephanodiscus astrea var3 29.75 E+ Chrysophyte Chromulina spl 624.75 E+ Chrysophyte Chrysochromulina sp. 684.25 E+ Chrysophyte Cryptomonas spl 29.75 E Chrysophyte Dinobryon cell spl 29.75 E+ Chrysophyte Dinobryon lorica spl 148.75 N Cyanophyte Oscillatoria sp2 743.75 E Other Ankistrodesmus spl 59.50 E+ Other Chroomonas acuta 29.75 N Other Gymnodinium spl 59.50 e Other Peridinium sp2 178.50 E+ Other Rhodomonos sp. 89.25 E+ Microalgae microflagellates 1,071 .OO E Microalgae picoplankton 1,279.25

11 E+ = prime, E = edible, e = not preferred but edible, and N = not edible.

Appendix 8.3. Phytoplankton density, volume, and carbon content for samples collected from station 1 at Glacial Lake, 1994.

Rating as Density Carbon Sample food source (no.cells/m3 Volume @g c/m3

11 date for zoop. Group Species x 1 06) (mm3/m3) X 1 03)

Diatom Diatom Diatom Diatom Diatom Diatom Diatom Diatom Diatom C hrysophyte C hrysophyte Chrysophyte Chrysophyte C hrysophyte C hrysophyte Cyanophyte Other Other Other Other Other Other Microalgae Microalgae Diatom Diatom Diatom Diatom Diatom Diatom Chrysophyte Chrysophyte Chrysophyte Chrysophyte C hrysop hyte C hrysop hyte Chrysophyte Other Other Other Other Microalgae

Achnanthes minutissima Cyclotella spl Cyclotella stelligera Fragilaria construens varl Navicula sp3 Nitzschia sp. Stephanodiscus astrea varl Synedra sp3 Tabellaria sp2 Chromulina spl Chrysochromulina sp. Crucigenia sp2 Crucigenia sp5 Dinobryon cell sp3 Dinobryon lorica spl Chroococcus sp3 Chroomonas acuta Flagellate sp4 Flagellate sp8 Gymnodinium spl Peridinium sp2 Rhodomonos sp. microflagellates picoplankton Asterionella formosa Cyclotella spl Cyclotella stelligera Fragilaria construens varl Fragilaria crotonensis varl Stephanodiscus astrea Chromulina spl Chrysochromulina sp. Dinobryon cell sp5 Dinobryon cell spl Dinobryon lorica sp3 Dinobryon lorica spl Mallomonas sp6 Chroomonas acuta Flagellate sp8 Peridinium sp2 Rhodomonos sp. microflagellates

E Microalgae picoplankton 2,082.50 11 E+ = prime, E = edible, e = not preferred but edible, and N = not edible.

Appendix B.4. Phytoplankton density, volume, and carbon content for samples collected from station 2 at Glacial Lake, 1994.

Rating as Density Carbon Sample food source (no.cells/m3 Volume (pg c/m3

11 date for zoop. Group Species x 1 06) (mm3/m3) X 1 03)

8/3/94 E Diatom Achnanthes minutissima 89.25 e Diatom Asterionella formosa 29.75 E Diatom Cyclotella spl 148.75 E Diatom Cyclotella stelligera 71 4.00 e Diatom Diatoma elongatum varl 29.75

Diatom Eunotia sp3 29.75 e Diatom Fragilaria construens varl 386.75 e Diatom Fragilaria crotonensis varl 59.50 e Diatom Melosira islandica 29.75 N Diatom Synedra sp3 89.25 E+ Chrysophyte Chromulina spl 238.00 E+ Chrysophyte Chrysochromulina sp. 178.50 E+ Other Flagellate sp4 59.50 E+ Other Flagellate sp8 59.50 N Other Gymnodinium spl 148.75 e Other Peridinium sp2 1 78.50 E+ Other Rhodomonos sp. 208.25 E+ Other Scenedesmus sp3 29.75 E+ Microalgae microflagellates 565.25 E Microalgae picoplankton 1,190.00

9/26/94 E Diatom Cyclotella spl 178.50 E Diatom Cyclotella stelligera 357.00

Diatom Eunotia sp4 59.50 e Diatom Fragilaria construens varl 238.00 N Diatom Navicula sp3 59.50 e Diatom Nitzschia sp. 59.50 N Diatom Synedra sp3 59.50 N Diatom Tabellaria sp2 59.50 E+ Chrysophyte Chromulina spl 41 6.50 E+ Chrysophyte Chrysochromulina sp. 476.00 E Chrysophyte Crucigenia spl 1 19.00 E Chrysophyte Dinobryon cell sp5 476.00 E Chrysophyte Dinobryon cell spl 1,190.00 E+ Chrysophyte Dinobryon lorica sp3 41 6.50 E+ Chrysophyte Dinobryon lorica spl 1,547.00 E+ Chrysophyte Kephyrion spl 1 19.00 E Chrysophyte Mallomonas sp6 59.50 E+ Other Chroomonas acuta 59.50 E+ Other Flagellate sp7 59.50 e Other Peridinium sp2 238.00 e Other Quadrigula sp2 59.50 E+ Other Rhodomonos sp. 1 19.00 E+ Microalgae microflagellates 1,547.00 E Microalgae picoplankton 1,071 .OO

11 E+ = prime, E = edible, e = not preferred but edible, and N = not edible.

The Alaska Department of Fish and Game administers all programs and activities free from discrimination on the basis of sex, color, race, religion, national origin, age, marital status, pregnancy, parenthood or disability. For information on alternative formats available for this and other department publications, contact the department ADA Coordinator at (voice) 907-465-4120, or (TDD) 907-465-3646. Any person who believes slhe has been discriminated against should write to: ADF&G, P.O. Box 25526, Juneau, AK 99802-5526' or O.E.O., U.S. Department of the Interior, Washington, D.C.