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Home My WebLink AboutAPA2328- SUSITNA HYDROELECTRIC PROJECT FINAL REPORT ,BIG GAME STUDIES VOLUME IX BELUKHA WHALE Donald Calkins ALASKA DEPARTMENT OF FISH AND GAME TK 1425 Submitted to-the Alaska Power Authority .58 B54 Apr i I 1984 00.2328 DOCUMENT No.2328 .- - -r!<,! 11J,5 ·t~< eft( no.JJ~g SUSITNA HYDROELECTRIC PROJECT FINAL REPORT BIG GAME STUDIES VOL.IX BELUKHA WHALE by Donald Calkins ALASKA DEPARTMENT OF FI SH AND GAME Submi tted to the Alaska Power Authori ty April,1'984 _~.5QglMJ;Q [""!=C I)'198")~-t...t,·.:''t ~..L~POWER AU1HOBII'{; AKLIS Alaska Resources Library &Information Services Anchorage,Alaska - - - - ?REF,~.CE In early 1980,the ~laska Department of Fish and Game cQ~tracted w~~h t~e Alaska Power Authority to collect info=mation useful in assessing the impac~s of the proposed Susitna Hydroelectric ?roj ect on moose,caribou,.wolf,wol'.rerine,black bear,brown bear and Dall sheep. The studies were broken into phases which conformed to the anticipated licensing schedule.Phase I studies,January I,1980 to June 30,1982,were intended to provide information needed to support a FERC license application.This included general studies of wildlife populations to determine how each species used the area and identify potential impact mechani sms.Phase I I studies began in order to provide additional information during the anticipated 2 to 3 year period between application and final FERC approval of the license.Belukha whales were added to the species being studied.In these annual or final reports,we are narrowing the focus of our studies to evaluate specific impact mechanisms,quantify impacts and evaluate mi tigation measures. This is the second annual report of ongoing Phase II studies.In some cases,obj ectives of Phase I were continued to provide a more complete data base.Therefore,this report is not intended as a complete assessment of'the impacts of the Susi tna Hydro- electric Project on the selected wildlife species. The information and conclusions contained in these reports are incomplete and preliminary in nature and subject to change with further study.Therefore,information contained in these reports is not to be quoted or used in any publication without the wri tten permission of the authors. The reports are organized into the following 9 volumes: - - Volume I. Volume I I. Volume III. Volume IV. Volume V. Volume VI. Volume VI I. Volume VI I I. Volume IX. Big Game Summary Report Moose -Downstream Moose -Upstream Caribou Wolf Black Bear and Brown Bear Wolverine Dall Sheep Belukha Whale ii /.R'~"'0i-\<J...Jl~ Alaska R~sources Library &Information Services Anchorage,Alaska Belukha surveys '.vere flown in upper Cook Inlet bet'.veen May 17 a::d l\UgUst 27,"'"_.-.....~~b.L..and.Apri 1 6 ~o July 1983 ..A concent.:"ation ,..... area was identified nearshore from the mouth of the Little Susitna River to the mouth of the Beluga River.Use of the area increased in 1 ate May and lasted through mid-June.It is prob- able that this concentration was in part associated with calving and breeding although no calves were positively identified because of generally poor viewing conditions.The concentration appeared to involve 200 to 300 animals,however accurate counts 'I'lere not possible because of,again,poor viewing conditions. The Belukha concentration near the mouth of the Susi tna River appeared to coincide with the arrival of large numbers of eulachon which spawned in the lower Susitna River in late May and l~arly June.This run of eulachon 'I'las estimated to total several million fish.King salmon are probably not particularly impor- tant to thi s concentration of belukhas although large male belukhas probably do take some king salmon.The only other salmon species from the Susi tna River system available in suf- ficient numbers to be considered significant prey to the belukhas concentrated in late May and early June is the sockeye.No information is presently available which would allow conclusions ~:>n belukha predation on salmon smol ts from the Susi tna River. Gi ven the present state of our knowledge,\we cannot accurately predict impacts ,on Cook Inlet belukhas from the proposed dams on "the Susitna River.It is possible that the overall population could suffer reduction in numbers both directly by alterations in "the habitat,particularly the concentration area near the mouth I:>f the Susi tna River and indirectly by reduction of available food species. iii - - - - "... TABLE OF CONTENTS SUMMARY ... LIST OF TABLES . 1.I ST OF FIGURES . . . INTRODUCTION . . . METHODS . . . . . . . . RESULTS AND DISCUSSION POTENTIAL IMPACTS RECOMMENDATIONS FOR FUTURE STUDIES . LITERATURE CITED . . . . . . . . . iv iii v vi 1 3 3 13 14 15 -- - - .- - Table 1. Table 2. LIST OF T.~.5LES Belukha surveys of upper Cook Inlet 17 May 1982 through 27 August 1982 .... Belukha surveys of upper Cook Inlet 6 April through 20 July 1983 . . . . . . . . . . . . ... . v 5 6 Figure l.Upper Cook Inlet belukha study area 4 E'igure 2.Locations in upper Cook Inlet where belukha whales were sighted in groups of 10 or more for the ,-month of May 1974-1979 8 Figure 3 .Locations in upper Cook Inlet where belukha whales were sighted in groups of 10 or more for the-month of June 1974-1979 .9 Figure 4.Locations in upper Cook Inlet wherebelukha whales were sighted in groups of 10 or more for the month of July 1974-1979 .10 -. vi - The be lukha whale (Delphinapterus leucas):.3 a small,~octhecl belukhas are all white ~n coloration,range from 3.1 to 4.4 m in- whale,',.,hich inhabits arctic and sub-arctic shaded with blue as the animal length and weigh 480-1200 kg.Males generally females.Newborn calves are a dark gray color, or brown.This coloration is gradually lost approaches the age of maturi ty. are larger ....',-nan .- .~ ! Belukhas range throughout Cook Inlet,concentrating in the upper Inlet in the spring and summer,and moving to the lower Inlet during the winter.There is some evidence which suggests that during some years some of the belukhas may leave the Inlet entirely and move across the north Gulf of Alaska to as far away as Yakutat Bay (Calkins 1979).In the north Gulf of Alaska, belukhas have been sighted in Shelikof Strait,near Kodiak Island,in Prince William Sound,and in Yakutat Bay (Fiscus, Braham and Mercer 1976j Harrison and Hall 1978;Calkins and Pitcher 1978;Calkins 1979j and Calkins,unpub.data).Some parts of these areas probably had large numbers of belukha,at least seasonally,but now the population appears reduced (Calkins,unpub.data).Recent sightings indicate ei ther these animals range outside of Cook Inlet during summer or more animals exist than we know about. The Cook Inlet stock of belukha whales was estimated at 300 to 400 animals by Klinkhart (1966)..Recent surveys in the Inlet have shown that the population exceeds 400 animals (Calkins unpub.data).However,all surveys of belukhas in Cook Inlet have consisted of aerial counts of shoreline areas.No complete systematic census of CC'"lk Inlet belukhas has been completed, therefore,no accurate estimate of the stock can be made.The best information we presently have is that there are over 400 w·hales which inhabi t Cook Inlet in the summer. 1 - - - Som~e~idence exists which suggests tha~t~e Cook I~l~t stock is qenetically isolated from other belukha whale stOC~:3.The next nearest stock of belukhas is the population which inhabits Bris"Col Bay.~ve kno'",'of no ins"Cance 'where any in.terchange has taken place between these t'wo stocks although the only true limi tation is the di stance of mi les between.Fay (pers.comm.) suggests that some morphological differentiation has taken place in Cook Inlet.He was able to examine a limited series of skulls from Cook Inlet and compared them to other areas.However,the Cook Inlet sample was too small to conclude that craniological morphology has actually changed in this stock. Belukhas are known to feed on a broad assortment of fishes and invertebrates in other areas,however no direct information is available on prey selection by belukhas in Cook Inlet.In Bristol Bay,belukhas concentrated on rainbow smelt (Osmerus mordax)in May and shifted to downstream migrating salmon smol ts by June 1.By late June,the Bristol Bay belukhas were con- centrating on adult salmon (Brooks 1954).Other food species utilized by belukhas in Bristol Bay were flounders (Pleuronec- tidae),lamprey (Lampetra sp),shrimp (Grangon sp.)and sculpins (Gottidae)(Brooks 1954).In Escholtz Bay,belukhas ate safron cod (Eleginus gracilis),sculpins (Gottidae)and small amounts of shrimp (Grangon sp.),isopods (Saduria sp.),snails (Polinices sp.),polycheatas (unidentified)and octopus (Octopus sp.) (Seaman et al.1982). Very little information is available on the belukhas'ability to tolerate perturbations in its environment.We know nearly nothing about the consequence of reducing the food supply or changing the heat budget of the river,however slight these changes might be.We do know that belukhas will abandon areas if t;he environmental perturbations are great enough as was the case i.n the St.Lawrence River where belukhas quit using the Mani- couagan and Outardes Rivers after they were damned for hydro- electric purposes (Sergent and Brodie 1975). 2 :'IETHCDS Shoreline aer~al surveys of 'upper Cook Inlet (Fig.1)~ere c-::mduct:ed periodically f:-om May 17 t:hrough .';ugUSi::'7,and ..... - .::',pr II 26 to July 20,1983,using single engine ai rcraft:wi th water landing capability.The surveys were generally flo~n at an altitude of 50 to 100 meters and approximately 500 meters off- shore from the immediate tide water line.When groups of belukhas were sighted,the altitude was increased to 200 meters and the groups were circled while two observers counted as many belukhas sighted as possible. Turbid water conditions along with short surface times for the belukhas prevented accurate and complete counts of all belukhas present.The numbers of belukhas counted represents a minimum number of animals which were present at the time of the count. 1m attempt was made to identify calves in all groups observed by circling and obser,ving at lower al ti tude. RESULTS AND DISCUSSION Belukha surveys are summarized in Table 1 and 2.A total of 9 surveys were flown in 1982 and 5 in 1983.Each survey covered the same general area of upper Cook Inlet shoreline,including all areas north of a line between the North Foreland and Moose Point (Fig.1).On the June 18th and June 22,1982 and the July 20,1983 surveys,the survey area was extended to the East and West Forelands.No neonates were posi tively identified on any of these surveys due to the turbid water conditions.How- E~ver,on both the May 17 and the June 4,1982 surveys,very dark, small belukhas were sighted.These could have been newborn calves although this was not determined because newborn calves and yearlings differ in length by approximately 30 cm (John Burns pers.comm.);determining 30 cm difference between animals from an aircraft at 100 to 200 m altitude and moving at an airspeed of approximately 80 kts with the belukhas in highly turbid water proved :to be an impossible task. 3 - E JI:ooo..•Go Go ;:).- .;•..•>-'0 ~..••&: JI: ~•JIll.. .! .5 :l Ci '0c:: .!•..o ~ ..••~ - 4 Table 1.Beluk~a sU~~jeys ~=upper Cook :nlet ~I May t~1!.-C ~'gr~27 .;Llgll S t 19:32. ..,,-"-"- ..L':J'::i~ ..... Date May 17 June 4 June 11 June 18 June 22 July 2 July 8 Aug.5 Aug.27 :--lumber Sighted 15 10 15 150-200 100 15 20 200-300 108 39 50-75 78 30 15 4 50-75 40 25 46 7 7 63 62 30 21 15 Location Sighted South of Little Susitna R. North of Beluga R. W.pt.Fire Island Between Susitna R.and Lewis R. Lewis R.to Beluga R. SW side Chickaloon Bay Chickaloon R.Mouth Lewis R.to Beluga R. Susitna R.Mouth Ivan R.to Beluga R. Beluga R.and Mouth Beluga R.to Tyonek village Chickaloon Bay Boulder pt.{N.of Kenai} Mouth of Susitna R. Lewis to Theodore R. Beluga R.and Mouth McArthur R.and Mouth Susitna R.to Beluga R. Beluga R.area Susitna R.Mouth to Beluga R. McArthur R.area Chickaloon Bay Potter Marsh Mouth of Beluga R. 5 - Table 2.Belukha surveys of upper Cook :r:.::"et 6 .=-.pril -chnJugh 20 July 1983 / .- Date April 6 April 28 ~ilay 27 June 24 ,July 20 Number Sighted 1 1 4 4 5 1 6 25 173 83 6 1 4 1 7 20 16 10 10 20 100 6 Location Sighted Knik Arm Mouth of Theodore R. Mouth of Beluga R. Chickaloon Bay Little Susitna R. W.side Susitna R. Mouth of Beluga R. Off Pt.Possession Mouth of Beluga R. Mouth of Theodore R. Chickaloon Bay Knik Arm N.of Anch. Off mouth of Theodore R. Off Pt.Possession S.W.of Fire Island S.E.Susitna R.mouth Lewis R.mouth Theodore R.mouth Beluga R.mouth 3 mi E.of West Foreland Off E.Foreland - Du~ing the 1932 3~=veysl one area ,was ide~~ified as a ccncentra- tion area.This area was just offshore fr.::m the water line ar;.d extended from the mouth of the Little Susitna River to just south of t.l1e rnollth of the Beluga :s:.i~..-e:~r,tlg ..1).::'gures 2 t~1~ougl1 -± show groups of belukJ.~as larger than ten which were recorded between 1974,through 1979 for May,June and July (numbers·in circles indicate size and location of groups).The general pattern shows few large groups in the upper inlet during May;a concentration of groups from the mouth of the Susitna River to Beluga River area during June;and groups scattered throughout the upper inlet during July. Use of this area appears to begin with a build-up of belukhas near the mouths of the Susitna River,the Lewis River and the Beluga River about mid-May which lasts through about mid-June. The belukhas had begun to concentrate in the area in 1982 by the first survey,May 17 (Table 1).In 1983,large numbers were not observed until the May 27 survey (Table 2).The concentration had broken up,and belukhas were sighted throughout the Inlet by June 22 in 1982.This was also the case in 1983,when few belukhas were sighted in the concentration area by June 24. There are several possible explanations which are immediately apparent for belukhas concentrating in the area near the mouths of the rivers in the northwest part of Cook Inlet.Concentra- tions in areas of river mouths in the spring is common to many belukha whale populations.Sergent and Brodie (1975)considered the primary reason for whales gathering at this time of year was calving and breeding while Fraker et al.(1978)felt that taking advantage of warmer estuarine temperatures in the spring was important to all segments of a belukha population,not just the reproducti ve age classes.They hypothesized that the thermal advantage to all age classes was the primary reasoh for spring 7 ,.... ~o o (J .'.Pt. '"Possession ":". Pt. Frgure 2.Locations In Upper Cook Inlet where beluklta wha.e •••re .Ighted In groups of 10 .r lIIor.for the month of May 1874 -1819. 8 - """ ~oo o Flgur.3.Locatlona In Upper Cook Infet wh.r.b.lukha wha.e.were .'ghted in group.of 10 or Rlor.for the month of .Il1ne 1874 -1879. 9 ~-"::@ (y +" CHISIK I., ~ .....0 0 CI -, ...., Flgur.4.Location.In Upper Cook Inlel where belukha whale.were .Ighled In group.of 10 or lItore for Ihe monlh of July 1874 -1878. 10 estuarine aggregations of belukhas,?.nd secon,ia.ri2.'j,the -.:::cn- centration areas may afford some shelter fr8m s~sr~s.Fraker et ""'" ~.(1978)felt that availabi:ity of an important food source was not a :naj -"Jr fac-::or for belukllas concen-cl-a-:ing in ~i::..e r1ac1(enzie estuary because most whales harvested by natives had empty stomachs.However,this may be a significant difference from the Cook Inlet stock of belukhas as well as the.Bristol ~ay stock. We know from Brooks (1954)and Lensink (1961)that belukhas do feed in the estuaries in the spring in Bristol Bay and may be primarily attracted to the area by both downstream migrating smolts and returning adults of several species of salmon as well as an early run of smelt. Belukha feeding in estuaries in Cook Inlet in the spring has not been positively determined.However,the presence and timing of several species of anadromous fish,similar to the conditions in Bristol Bay,suggest this to be the case.Probably the single most important fish species to the belukhas in Cook Inlet in the concentration area in the spring is the eulachon (Thaleicthys pacificus)which arrives in the Susi tna estuary and enters the river for spawning in two major migrations.In 1982,the first was detected in the river when sampling began on May 16 and lasted until approximately May 30.The second migration of eulachon followed from June 1 until June 8 in 1982.In 1983,the first migration occurred in mid-May from May 10 through May 17 and the second migration occurred from May 19 through June 6 (Barrett et a1.1984).In both years,the escapment was con- sidered to be several hundred thousand fish for the first migra- tion,while the second migration was estimated to total several million fish (Barrett et a1.1984)Brooks (1954)found that smel t (Osmerus dentax)were important in the diet of belukhas in Bristol Bay very early in the spring,shortly after breakup. Eulachon are similar in size and habits to smelt and probably are analogous in the diet of Cook Inlet belukhas. 11 j\f ter ::he 3me':""t :"'.11':dec:rea sed by the e:1d 0 f 1'1 a y ,be 1 ukha sin Bristol 3ay s~i~c:hed ~o downstream migrating salmon smelts (Brooks 1954).Lensi~k (1961)felt that as the smolts moved out ·~f -+:he est~ary a:1d.i::tQ 3ri 3 tal Bay J t:~ey apparen~ljr'seat t.e::.-ed and became rrrt..:.ch less vulnerable to predation.Thus of six .... ,.,., - ..... - belukhas taken between June 6 and June 15,none had eaten smelts. If this is also the case in Cook Inlet,then it is possible that salmon smolts from the Susitna River may not be an important food source.However,Cook Inlet is somewhat different from Bristol Bay.At low tide,extensive sand bars are exposed with the majority of the Inlet's water confined to channels and waterways, considerably smaller then Kvichak or Nushagak Bays in Bristol Bay.Al though the belukhas apparently seldom enter the Susi tna River,the salmon smolts may be concentrated enough at low tide outside the river mouth to allow the belukhas to feed on them. Certainly,no realistic estimate of belukha use of salmon smolts in Cook Inlet can be made without examining stomach contents of the belukhas. Adul t king salmon (Oncorhynchus tshawytscha)are avai lable in the area of the Susitna River (ADF&G,unpub.data),from mid-April through August with a peak in June.However their value to belukhas as a food source is questionable.Brooks (1954)did not find adult king salmon to be a significant component of the diet of belukhas in Bristol Bay and speculated that only the smaller adult king salmon were taken by the largest adult male belukhas. If this is the case in Cook Inlet also,probably adult king salmon are taken only in small numbers. All four of the other species of North American salmon enter the Susi tna River to spawn but probably only the sockeye (Oncorhyn- chus nerka)would likely be present in numbers sufficient to provide a significant food source during the time period when the belukhas are concentrated near the mouth of the Susi tna River. However,even sockeyes do not become abundant in upper Cook Inlet until after July I,after the concentration of belukhas has dispersed. 12 -Quar.~ification of impacts of the Susitna hydroelectric p~0ject on belukhas a'::the p~esent time is r:ot possible.This tjpe of de"..lelopment proj ect has the potential for reducing the numbers concentrating near the mouth of the river by reducing the avai 1- able food or by altering the heat budget of the river.However the overall effect on the availability of anadromous fish to belukhas is predicted to be small.There may be no alteration of the heat budget of the river realized by the belukhas at the mouth of the river,although very little data are available to prove this. Approximately 5 to 8%of the total adult salmon returning to the Susi tna River system spawn in the area from Talkeetna to Devil Canyoni the area which is predicted to be the most heavily impacted by dam construction.The slough habitat in this area is predicted to be reduced,thereby reducing the available habitat of the chum salmon from the system as well as a small number of sockeye.This means that a small amount of food in the form of adult chum and sockeye may no longer be available to the belukhas after dam construction.Since we have no quantitative measure of the importance of these species to the belukhas,no estimate of impact can be made except to guess that it will probably be slight. Impacts on the eulachon runs which enter the Susi tna River are assumed to be slight as they remain in the lower reaches of the river (Bruce Barrett ADF&G pers.corom.).This species may be extremely important to the belukhas and it is possible that any reduction of eulachoncould severly impact the belukhas. Although most impacts from either heat budget alteration or food reduction are likely to be slight,we cannot accurately predict the overall effect on the belukhas.If any environmental pertur- bations effect the belukhas in upper Cook Inlet,it is likely 13 -, .- - ..... ~he3e effects '..,rill take ::1:.e form of a re,j:uc::::'on in the pcpula";:ion ~n Cook Inlet.Given our present state of knowledge,a reduc::ion in ::he be'i.:..ckha population of upper Cook Inlet -,vould not be detec~ab~e u~less it were greater tl:an a 5C~to 75%reduction in the entire population.Even a reduction of this magnitude could go unnoticed for several years as no systematic monitoring of the population is planned. RECOMMENDATIONS FOR FUTURE STUDIES The most immediate information need for the Cook Inlet belukha population with respect to the Susitna hydroelectric project is a reali stic population estimate.Generation of such an estimate would require development of a systematic aerial census of the belukhas in the entire Inlet from which a statistically sound estimate could then be derived.Beyond that,future studies should involve collections of skulls in order to determine the taxonomic status of this pop-qlation;food habits'studies to positively identify and qu~ntify the importance of food species; and movement studies to define the geographical range and seasonal movements of the population . 14 L~TERATURE CITED Barrett,B.riJ.,F.IvI.Thompson,and S.N.~lick.1984.Adult - .- -- - -- anadromous fi sh investigations:i1ay-October 1983.Alaska Department of Fish and Game,Susitna Hydro Aquatic Studies Report No.1.Prepared for Alaska Power Authority.225 pp. plus appendixes. Brooks,J.W.1954.A Preliminary Report on Beluga Investiga- tions In Bristol Bay.Alaska Dept.of Fisheries.Unpub. MS.39p . Calkins,D.G.1979.Marine Mammals of Lower Cook Inlet and the Potential Impact from Outer Continental Shelf Oi 1 and Gas Exploration,Development and Transport.In:Environmental Assessment of the Alaskan Continental Shelf Final Report of Principal Investigators Vol.20 Dec.1983,171-264.USDC, NOAA,National Ocean Service,Office of Oceanography and Marine Services,Ocean Assessments Di v.Juneau,AK. Calkins,D.G.and K.W.Pitcher.1978.Population assessment, ecology and trophic relationships of Steller sea lions in the Gulf of Alaska.pp.373-413.In:Environmental Assessment of the Alaskan Continental Shelf Final Report of Principal Investigators for the year ending March 1978. Vol.1 -Receptors-Mammals.NOAA,Outer Continental Shelf Environemtnal Assessment Program,Boulder,Colorado,775 pp. Fiscus,C.H.,H.W.Braban,and R.W.Mercer.1976.Seasonal distribution and relative abundance of marine mammals in the Gulf of Alaska.Processed Report,Marine Mammal Di v.NMFS, Seattle.238pp. Fraker,M.A.,D.E.Sergeant and W.Hoek.1978.Bowhead and white whales in the southern Beaufort Sea.Technical Report #4,Beaufort Sea Proj.Canada Dept.of Fi sheries and the Environment.Sidney,B.C.113pp. 15 Harrison,and ,J.D.Hall.Alaskan Distribution ......: 0.-/..:.... the beluga whale, 92:235-241. Oelphinapteru5 leucas.Can.E'ielj-Nat. Klinkhart,E.G.1966.The beluga ',.;hale in Alaska.Unpub. Report,Alaska Department of Fish and Game,Juneau,Ilpp. Lensink,C.J.1961.Status Report: Dept.of Fish and Game,Div.of Report.36pp. Beluga Studies. Bio.Research. Alaska Unpub. Seaman,G.A.,L.F. belukha whales Cetology 44:1-19. Lowry and K. (Delphinapterus J.Frost. leucas)in 1982. western Foods of Alaska. .- Sergeant,D.E.and P.F.Brodie.1975.Identity,abundance and present status of White whales (Delphinapterus leucas)in North Arnerica.J.Fish.Res.Bd.Canada.32:1047-1054 . i6 I"""" i 'E:aYI ~n.J Uni"'1ersity of .~laska,I::5--::"~ute of r~'!al"ine Sc:'ences l ::airbanks,Alaska 99701,October 1977 Burns,J.J.,Alaska Depar::mentof Fish and Game,:300 College Road J Fairbanks J .~laska 99701 J March 1982 Barrett,B.Mo,Alaska Department of Fish and Game J 2207 Spenard Road J Anchorage,Alaska 99503,February 1983 17