Translation Series No by V. V. Zimushko

Transcription

1 FISHERIES RESEARCH BOARD OF CANADA Translation Series No AR Olnn:,:,4 Aqro-Visual censusing of population and observations on the distribution'of Grey Whales in coastal waters of the Chukchi - Sea by V. V. Zimushko Original title: Aerovizualnyy uchet chislennosti i nablyudeniya za raspredeleniem serykh kitov v pribrezhnykh vodakh Chukotki From: Izvestiya Tikhookeanskogo Nauchno-Issledovaterskogo Instituta Rybnogo Khozyaistva i Okeanografii (TINRO)' (Proceedings of the Pacific Scientific Research Institute of Marine Fisheries and Oceanography), 71 : , 1970 Translated by the Translation Bureau(GNK) Foreign Languages Division Department of the Secretary of State of Canada Department of the Environment Fisheries Research Board of Canada Marine Ecology Laboratory, Dartmouth, N.S. Arctic Biological Station, Ste. Anne de Bellevue, P.Q pages typescript

2 DEPARTMENY OF THE SECRETARY OF STATE TRANSLATION BUREAU.Fee SECRÉTARIAT O; ÉTAT BUREAU DES TRADUCTIONS MULTILINGUAL SERVICES DIVISION CANADA DIVISION DES SERVICES MULTILINGUES TRANSLATED FROM - TRADUCTION DE INTO EN Russian English AUTHOR - AUTEUR V.V. Zimushko TITLE IN ENGLISH - TITRE ANGLAIS - Aero-Visual Censusing of Population and Observations on the Distribution of Grey Whales in Coastal Waters of the Chukchi Sea. TITLE IN FOREIGN LANGUAGE (TRANSLITERATE FOREIGN CHARACTERS) TITRE EN LANGUE ÉTRANGÈRE (TRANSCRIRE EN CARACTÈRES ROMAINS) Aerovùzualnyy uchet chislennosti 1 nablyudeniya za raspredeleniem serykh kitov v pribrezhnykh vodakh Chukotki. REFERENCE IN FOREIGN LANGUAGE (NAME OF BOOK OR PUBLICATION) IN FULL. TRANSLITERATE FOREIGN CHARACTERS. RÉFÉRENCE EN LANGUE ÉTRANGÈRE (NOM DU LIVRE OU PUBLICATION), AU COMPLET, TRANSCRIRE EN CARACTÈRES ROMAINS. Izvestiya TINRO REFERENCE IN. ENGLISH - RÉFÉRENCE EN ANGLAIS Transactidns of the Pacific Research Institute for Fiàheries and Oceanos,,raphy. FUBLISMER ÉDITEUR PLACE OF PUBLICATION LIEU DE PUBLICATION TINRO YEAR ANNÉE DATE OF PUBLICATION DATE DE PUBLICATION VOLUME M.,,Igadan, USM. WO ISSUE NO. NUMÉRO PAGE NUMBERS IN ORIGINAL NUMÉROS DES PAGES DANS LORI GINAL NUMBER OF TYPED PAGES NOMBRE DE PAGES DACTYLOGRAPHIÉES REQUESTING DEPARTMENT MINISTÈRE-CLIENT Envtronment TRANSLATION BUREAU NO. NOTRE DOSSIER NCI BRANCH OR DIVISION DIRECTION OU DIVISION Fisheries Service TRANSLATOR (INITIA LS) TRADUCTEUR (INITIALES) GNK PERSON REQUESTING DEMANDÉ PAR Dr. P.F. Brodie UNEDITF.D TRANSLATION YOUR NUMBER VOTRE DOSSIER NCI DATE OF REQUEST DATE DE LA DEMANDE November 22nd e For information only TRADUCTION NON REVISEE Inforindion seulement 80S (Re v. 2/68)

3 DEPARTMENT OF THE I SECRETARY OF STATE TRÂNSLATION BUREAU MULTILINGUAL SERVICES DIVISION ECRÉTARIAT D'ÉTAT BUREAU DES. TRADUCTIONS DIVISION DES SERVICES MULTILINGUES CLIENT'S NO. DEPARTMENT DIVISION/BRANCH CITY N0 DU CLIENT MINISTÉ.RE DIVISION/DIRECTION VILLE Environment Fisheries Service. Ottawa BUREAU NO. LANGUAGE TRANSLATOR (INITIALS) N 0 DU BUREAU LANGUE TRADUCTEUR (INITIALES) Russian GNK FEB AERO-VISUAL CENSUSING OF POPULATION AND OBSERVATIONS ON 'THE DISTRIBUTION OF GREY WHALES IN COASTAL WATERS OF THE CHUKCHI SEA " f.)1t 7.1) T 151,AT 10 N Voi- ez,ny By V.V. Zimushko -1.P.:11.DUCTI:17)1q N R 15 is Irieirma'riort. se Arrtrot (From: "Izvestiya TINRO" /Transactions of the Pacific Research Institute for Fisheries and Oceanography/, Vo 1ume - 71, 1970, pp , Magadan). In the Forties of the Nineteenth century the California-Chukchi population of grey whales had from 25,000 to 50,000 head (Scammon, 1874). Later these whales were twice on the brink of extinction and less than one hundred could be counted at their breeding areas. Whaling restricting. for these whales in 1946 had a positive effect on the population level and in 1955, according to R. Gilmore (1956) the population rose to 4500 head, and in 1960 R. Gilmore counted 5000 head at the breeding areas. At the same time D. Rice (1961) estimated the numbers of grey whales to be 6069 head at permissible deviations from 3984 to 8449 head. According to M.M. Sleptsov (1961) the numbers of grey whales in 1961 were approximately 2500 to 3000 head. In 1962, V.M. Latyshev and V.I. Troynin conducted SOS

4 observations from search ships on whales in the coastal waters in the Chukchi Sea. They encountered 1033 grey whales (Berzin and Rovnin, 1966). The quoted data were taken during whale censusing from shore or from ship. Annual aerial censuses since 1952 have been made by foreign observers at the wintering places of grey whales. By the most recent data of, aerial censusing the numbers of the California-Chukchi population of grey whales was determined to be approximately 3000 head (Hubbs C. and Hubbs L., 1967). C. Hubbs and L. Hubbs, in the same work, point out that according to information from Mexico the total size of the population is 15,000 head. They question this figure, calling it improbable. Thus, opinions of, individual researchers concerning the numbers of grey whales during the same years are rather contradictory. For this reason we find it necessary to continue censusing operations. In 1968, we carried out aero-visual censusing of the numbers of grey whales in waters of the Chukchi Sea. In addition to the author, observer-pilot A.V. Yevzerov took part in the operations and was of considerable assistance, for this the author is most.grateful. Previously no aerial censusing has been carried out on grey whales in waters of the Chukchi Sea, only unrelated observations are available on their distribution, which were carried out parallel with the censusing of the Pacific whalrus (Fedoseyev, 1966). In.addition to the grey whales in the coastal zone we noted a small number of other species of whales: humpback whales -, Mink& whales. - and white whales. However, we are only going to discuss.thé-problede

5 3 of distribution and numbers of grey whales. Research Methods Whale reconnaissance was carried out from 10th to 30th of July from an IL-14 plane and 68 flying hours were spent on flights. The coastal zone of the northwestern part of the Bering Sea was searched /p.290 (the region from Cape Khatyrka to Cape Navarin), as well as the coastal zones of the Anadyr Bay, Bering Strait and'chukchi Sea (fig. 1). In the Chukchi Sea the operations were carried out from Cape Dezhnev to the fringe of pack ice and at Herald Island. Fig. 1. Observations on whales in the coastal waters in the Chukchi area. We know from published data that the main portion of the grey whale population during the summer is in the coastal shallow portion of the

6 mentioned tegions. FurtherMore, a small number of these whalés live near the shores of Alaska. This distribution in a relatively narrow coastal zone is connected with the ecology of this species, mainly due to their feeding characteristics. The censusing operations were based on this phenomenon. The width of the surveyed zone (distance from the shore) was not less than 50 kilometres; in certain instances, when the shallows extended further away from the shore, flights were made as far seawards as 100 kilometres. The total area of the Covered zone was 107,900 square kilometres. The zone was.overflown in parallel tacks. The total length of the route measured along the tacks was 7890 kilometres. The distance between. the -tacks was 5, 10, 15, 20 or 30 kilbmetres. Most often the tacks were made at intervals of 15 kilometres. We believe that these intervals were optimal. It is known that grey. whales move at a speed of up to 18 kilometres per hour (Tomilin, 1962). At tack length of 100 kilometres and intervals between them of 5 and 10 kilometres cases of double recording of some of the animais is evidently possible, although not really. During flights. the observatiorswere carried out from one side of the plane at an altitude of 200 to 300 metres. In our calculations we assumed that the observation width was 500 metres. At this distance we could determine the species of animais with sufficient certainty. In some instances whales were visible from an altitude of 300 metres to a greater distance than the 500 metres, but to àvoid errors in species determination a half-kilometre observation width was set. The routes of flights were plotted on a map and the areas of the observa regions were

7 5 calculated. Then, when the observation width and the number of whales encountered were counted an extrapolation for the entire region was carried out. Undoubtedly the number of whales observed at a given moment on /p.291 the surface of water does not reflect the actual thi because the whales do not plunge and surface simultaneously. Therefore, for the determination of the true number of whales it is necessary to use a correlation coefficient. The value of this coefficient can fluctuate because of a number of factors and in particularly due to weather conditions. For example, even small waves at sea make observations considerably more difficult and low fog precludes the observations completely. Certain researchers suggested for the determination of the true number of whales to increase the number of individuals seen at the water surface at a given moment of observation by 3 to 5 times (Dorofeyev, Klumov, - according to Timoshenko, 1967). Unfortunately, we had no possibility yet to establish such a coefficient for aerial censusing of grey whales. C. Hubbs and L. Hubbs (1967) who for a period of successive years carried out aerial censuses of grey whales at their winter habitat, believe that during observations from a plane one half of the population is recorded. We share this opinion and believe that the average number of recorded whales equals the number.of the non-recorded ones, and for the calculation of the total - number of whales we used coefficient "2". DISTRIBUTION AND NUMBERS OF GREY WHALES IN COASTAL WATERS OF THE CHUKCHI AREA We know from published data that at fattening places of grey whales

8 6 the latter are not uniformly distributed. Taking these data into consideration, to decrease the probability of errors in the calculations we have divided the entire surveyed territory into several regions. The observation regions, the areas of the surveyed regions, the density of accumulations per square kilometre and the numbers of whales in the individual regions are shown in table 1. Table 1. Results of aerial censusing of grey whales in the coastal waters of the Chukchi area.. Pullout' D azi:1ju 7",..: :,. -..1; ,.. 11 P r,.r , ;,utracri- 4n,,,...,.., i.,. H..,.....; nn 9.1 Ou-.iefo., C.1!1:,4X. II.13- Illr.,!, ( v. 11::. M m. retza î r( (t:oca m. o 1.`.11:3 (M. Kpr ,02 1 7) , ) 278 C , , C1 0,04 o li : :;.irii :It:,...:.I..: 11,-...li 17 l.1 1.; 4,-. :,.-,- ; ;...0 mope --GI' K..).,-,:. 11,:, ;:li,;7f, :; 1 NI. at-ii.: 163.z.-;,!: I..,,--; _ r7 13 c e : ; St7: 14 1! ZT Mt UZI' i>7.? 2 es 9,24 r iz ;ter Key to the above table: 1. Regions; 2. Area of the stirveyed territory, in square kilometres; 3. Calculation numbers of whales in the surveyed areas, number of specimens; 4. Accumulation density of whales per square kilometres; 5. Cape Khatyrka - Cape Navarin; 6. Cape Navarin - Cape Barykov; 7. Cape Barykov - Cape Gek; 8. Cape Gek - Cape Ratken (qeyechkin Spit);

9 7 9. Cape Ratken - Cape Chukchi; 10. Cape Chukchi - Cape Nygligan; 11. Mechigmenskiy Bay; 12. Bering Strait (Cape Kriguygun - Cape Dezhnev); 13. Chukchi Sea - at the fringe of ice from Herald Island to the traverse of Cape Schmidt; 14. Chukchi Sea-from Cape Schmidt to Neshkan Spit; 15. Chukchi Sea-from Neshkan Spit to Cape Dezhnev; 16. Krest Bay (Cross Bay); 17. Total none. A total of 124 grey whales were recorded during the tacks, later calculations of the total numbers were based on this figure. The whales occur most often individually or in small groups of 3 to 5 head. The largest group observed simultaneously consisted of 17 specimens. It was recorded in Inchoun region (Chukchi Sea). In the Chukchi Sea, grey whales only occurred in the region from Cape Dezhnev to Cape. Neshkan; in the remaining portion of the sea, to the north of the Neshkan Spit along the fringe of ice to Herald Island, no whales were observed. Along the transverse of Cape Serdtse-Kamen' they occurred 90 kilometres from the shore. A.A. Berzin and A.A. Rovnin (1966) pinpoint the northern boundary of the summer area of grey whales to run in the Chukchi Sea along 69 N. and the western boundary - in the region of the Nutauge and Tankergyn-Pylgin lagoons. Our data agree with this. In Bering Strait the whales were observed at Cape Pouten, in. Mechigmenskiy Bay and at the transverse of Arakamchechen Island. \ In the region of Anadyr Bay the maximum amount of grey whales was observed at Cape Barykov, individual specimens occurred at Cape Gek, Meyechkin Spit and at the exit from Provideniye Bight. In the sector

10 ranging from Provideniye Bight to Meyechkin Spit and in the Krest Bay no whales were observed. Researchers usually considered the regions of Cape Khatyrka and Cape Navarin to be areas of the most dense concentration of grey whales (Tomilin, 1957; Arsenyev, 1961; Berzin and Rovnin, 1966; and others). In July 1968, we observed only individual specimens in the area from Cape Barykov to Cape Navarin and from Cape Navarin to Cape Khatyrka. We have not surveyed the region to the south of Cape Khatyrka, because of poor meteorological conditions. Judging from published data the grey whales were common even in waters around Kamchatka and the Komandorskiye Islands (Grebnitskiy, 1904, according to Tomilin, 1957). In recent years the whales did not occur along the western coast of the Bering Sea south of the Glubokaya Bight (Tomilin, 1957; Berzin and Rovnin, 1966). In particular, A.A. Berzin and A.A. Rovnin write: "... along the western coast of the Bering Sea individual whales occur in the Severo- Glubokaya and Natalia Bights. To the south, in the region of the Olyutorskiy Bay grey whales have not been observed even once during numerous cruises of search vessels." Taking the above into consideration, one can, apparently, admit that in the given region a small number of whales remained unobserved.by us. - It has already been noted that when flying over the area one went at.least 50 kilometers seawards and in individual instances as far as 100 kilometres. At the boundary of the surveyed zone whales were found on three occurrences: two groups with three specimens in each on the transverse of Cape Serdtse-Kamen i 90 kilometres from -Éhe shore and two single individuals

11 9 in the Anadyr Bay at a distance of 50 kilometres from the shore. In all the other instances the whales were not more than 35 kilometres from the shore. Apparently the bulk of grey whales coming to fatten in our waters were within the surveyed zone. Some whales might have possibly been in the open sea, but their numbers there we're insignificant. Ch. Scammon (1874) wrote that grey whales occur rarely in the open sea. Also during migration the grey whales pass through a relatively narrow "coastal corridor". Thus, for example, R. Gilmore (1960) reports that during migrations northwards at Vancouver Island and near the city of San Francisco the whales pass within four-miles of the shore. He believes that only approximately 5% of all the whales passing in the coastal zone pass far from the coast. F. Wilke and K. Fiscus (1961) observed during spring migration groups of grey whales 5 to 15 miles from the shore. The total number of grey whales in the coastal waters of the Chukchi area was calculated with the use of a correction coefficient to be approximately 4800 head (table 1) in the surveyed sea territory. Part of the summer was not covered by our observations. As already mentioned earlier, the region south of Cape Khatyrka was left unsurveyed and the coastal zone at the shores of the Alaska Peninsula remained outside of /p.293 ou observations. We had no opportunity to carry out censusing operations in the Alaskan waters and there is very little published information on grey whales in this region. Maher (1960) reports that grey whales migrate as far as Cape Barrow. This author gives certain data on nine whales killed in 1954, 1958,and 1959 by Eskimoes at Wainwright settlement and at Cape Barrow. F. Wilke and K. Fiscus (1961) report seeing grey whales

12 10 at the Alaskan shores in August, From August 10th to 29th at ' N. and ' W and in the nearest regions they observed from the observation ship three groups of grey whales of 2 to 3 and 20 head. In addition to these, two large accumulations of up to 100 head were observed (at 67 10' N ' W. and 67 25' N ' W.). These data testify that a certain number of grey whales regularly visits the coastal waters of the Alaska, but we do not know exactly how many. We have published information that grey whales sometimes stay for the summer at their wintering places at the California coast. In 1940, in summer time, a small group of grey whales was observed north of Humboldt Bay (Gilmore, 1960). In the same work Gilmore informs that in September 1947 and in June 1948,1e observed 12 to 15 whales in the Pelican Bay (northern part of the state of California). Ishihara (1958) reports on encounters with grey whales in summer at the southern part of the Bering Sea. These were individual specimens and they might have stayed in the mentioned region accidentally. Thus, taking all the factors in consideration, which might have had some effect upon the completeness of the censusing coverage of the entire population, we assume that aerial observations covered approximately 90% of the entire population. Accepting this statement, we may assume that the California-Chukchi population of grey whale is probably slightly more than 5000 head. Conclusions Thus we have counted in the coastal waters of the Chukchi area about 4800 grey whales and the entire population, apparently, has slightly

13 11 over 5000 head. Undoubtedly, these data do not claim to be very accurate, but may be accepted in their initial approximation. Special aerial censusing of grey whales in the waters of the Chukchi area was carried out for the first time and, naturally, the censusing is not perfect. In particular, it is very important to know accurately the correction coefficient. We have used data of C. Hubbs and L. Hubbs (1967), which are based on long-term observations. For greater reliability it is necessary to determine this coefficient more accurately taking meteorological conditions and other factors into consideration. Due to circumstances beyond our control we had no opportunity to census whales in the coastal waters of Alaska. This also had some effect upon the accuracy of our determination of the total numbers of the population. During the censusing we surveyed the coastal zone approximately 50 kilometres in width. Although at the boundary of this zone the whales occurred only three times and in other instances stayed closer to the shore, it is still quite possible that a certain number of them might have been farther out in the open sea. For greater certainty.it would, apparently, be expedient to survey a wider coastal zone. Regardless of its faults, the aerial censusing of grey whales today may be considered the mogt effective and prospective method compared with other methods (from the shore or from a ship). This operations must be continued in the future. BIBLIOGRAPHY 1. Arsenyev, V.A., Occurrence of whales in the Bering Sea

14 12 and prospects of whaling development. Transactions of the conference on ecology and hunting of marine mammals. Published by the USSR Academy of Sciences, Moscow. 2. Berzin, A.A., Rovnin, A.A., Distribution and migration of whales in the northeastern part of the Pacific Ocean, Bering Sea and Chukchi Sea. Reports of the All-Union Research Institute for Marine Fisheries and Oceanography, Volume 58, Vladivostok. 3. Sleptsov, M.M., Fluctuation in whale numbers in the Chukchi Sea in different years. of Animal Morphology, No. 34. Transactions of the Severtsov Institute Published by the USSR Academy of Sciences. 4. Timoshenko, Yu. K., Aerial observation on the white whale during summer-fall period in the White, Barents and Kara Seas. Transactions of the Polar Research Institute for Marine Fisheries and Oceanography, No. 21, Murmansk. 5. Tomilin, A.G., Whales, Volume IX, series "Animals in the USSR and adjoining countries". Published by the USSR Academy of Sciences, Moscow. 6. Tomilin, A.G., Whàle fauna in the seas of the Soviet Union. Published by the USSR Academy of Sciences, Moscow. 7. Fedoseyev, G.A Aero-visual observations on marine mammals in the Bering and Chukchi seas. Reports of the Pacific Research Institute for Fisheries and Oceanography, Volume 58, Vladivostok In English.

15 Bibliography Ap c en ben B. A Pacupoc -rpancinie r u Bepusiroliom mope n nonmmizstoctir pa3initur Kii -ro6orinoro npombicla. Tp. coacafainui rio 3K npombicay mopcmix ninekonuratounix. 113a-Bo All CCCP, M. -2. B e p 3 it A. A., Ponnun A. A Pacripe;leneinie n murpainin Kwron 13 cetepo-coctotnioii inicni 'fluor() OKealla, B Bepiniroaom 11 MyKOTCKOM mopax. Haa. THIIPO, T. 58, 13.1a.-urnoc -rom. Cmenno 13 M. M Role6atuni 3111CaellilOCTI1 KIITOB t gyk0fokoni Mope ri pa> ro:nst. Tp. um, CeBenuoua, r,iii. 31. I13,-uco AH CCCP. T 11 m o tu ell K 0 O. K. c camojeta 3a pactipe.;eaelinem 6e;iyx n 13 JpeTne-oceinturi nepsioe, B Beaom, Bapenneuom i 1-',apcKom mops-ix. Tp. 13 WI. 21, Alyp T o M 11.,-1 u 11 A. U Kit -rooc:pasiible, T. IX; cep. 3uepu CCCP u lipsimcw 113.-f,r,o A11 CCCP, M. is '1' o A.. F ii -rooc,pa3sime epaylim s.iopefi CCCP. 1I3,-..-no AH CCCP, M. '7 (I") e oc eee r. A ADFOL1113y11:13,111_,Ie 11; 6;in i 3;1 M 0i10E,iM :1111T;3 10- ILIUM 11 B Bt*ililrof/OM 11 tiy1.0w.kom MG:1:1X. 1.4:i13. T111.1P0, -r. Gilmore R. M The Ciilifornia gray Zoonooz. vol. Y. N 2. i 1 rrt 0 r e R. M A celisus of the California gray whcle. Spec. Sccientific Report: Fisch. N 342. Waschington. ubbs Ccrl, Hubbs Laura Gray whale censuses by airplane in Mexico. «Cal if. Fish. and (3:: Me» 53. N 1, shihar a T. 195S. Grav wi,;41e observed in the Be ring Sea, Sci. 1Zep. What. Inst. N 13. aher \V. I. 195D. Pc:c.cril records of tht. California gray whale (E. g,laucus) along, the North coast of Al Arctic, V. 13, N 4. kic e D. W. it\-;1. Ce1.V.is of the Calif.:1rnia Gray Whale, 1959! 60, N 6. Sca ranion Ch. M Th c l' Xarine. mammals of north coast of North America, San Francisco. 4, illke F. am.' Fiscus K. I-1, Gray whslle observations. 1. Marnmol.agy. N 1. vol. 42.