observation of the gray whale (eschrichtius robustus) in the laptev sea

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ISSN 10623590, Biology Bulletin, 2013, Vol. 40, No. 9, pp. 797–800. © Pleiades Publishing, Inc., 2013. Original Russian Text © O.V. Shpak, D.M. Kuznetsova, V.V. Rozhnov, 2013, published in Zoologicheskii Zhurnal, 2013, vol. 92, No. 4, pp. 497–500. 797 The gray whale (Eschrichtius robustus, Lilljeborg, 1861) as an Arctic species with seasonal migration may serve an indicator for climate changes in the Arctic (Moore and Huntington, 2008). The gray whale ear lier inhabited the Pacific and Atlantic oceans and the adjacent northern seas; however, by the beginning of the 18th century, this species had been extirpated in the Atlantic (Mead and Mitchell, 1984). In the Pacific Ocean, two gray whale populations are recognized (LeDuc et al., 2002): Okhotsk–Korean and Chukotka– Californian. The Okhotsk–Korean population spends summer in the Sea of Okhotsk, while the Chukotka– Californian population summer feeding grounds lie mainly in the Arctic between 174° E and 130° W in the Bering, Chukchi, and Beaufort seas; there are records of the gray whales visiting the East Siberian Sea (Rice, 1998). In the summer months of the years with poor ice conditions, individual gray whales were sighted near the mouth of the Kolyma River (Bogoslovskaya, 2002) and even more westward, “on the approach to the New Siberian Islands” (Matishov et al., 2000), namely, according to the map scheme in the publica tion, between 153° E and 158° E. In the fall, the Chukotka–Californian population migrates south ward, crosses the Pacific Ocean, and descends along the North American coast to California and Mexico to their reproduction area; and in the spring these whales again cross the ocean to return to the north, to the coasts of Kamchatka and Chukotka (Swartz et al., 2006). Recently, the gray whale was again recorded in the Atlantic basin. On May 8, 2010, an individual of this species was observed in the Mediterranean Sea off the Israeli coast and, three weeks later, near the coast of Spain. The proposed explanation, supported by many specialists, was that this gray whale had entered the Mediterranean Sea by the Northern Sea Route (Scheinin et al., 2011). No matter what brought this gray whale to the Mediterranean, its migration along the northern Eurasian coast became possible due to a considerable reduction in the icecovered area in the Arctic. In September–October, 2011, a series of observa tions on marine mammal distribution was conducted under the White Whale Program onboard the RV Mikhail Somov in the White, Barents, Kara, and Laptev seas. The observations were conducted from a platform located at 18 m a.s.l. At the beginning of each shift, as well as additionally in the case of changing conditions, the meteorological parameters (cloud cover, pres ence/absence of precipitation, wind direction and force) and quality of visibility (sea state according to the Beaufort scale, presence and position of the sun glare, and general estimate of visibility according to fivepoint scale) were recorded. When marine mam mals were sighted, the species, number, vessel GPS coordinates (using a Garmin 60csx) at the moment of detecting animals, distance to the animals, and bear ing angle relative to the vessel course were recorded, as well as their behavior when possible. The animals were photographed with a Nikon D300S camera equipped with Nikkor 80–200 mm f2.8, 70–200 mm f2.8, 18– 200 mm f3.5–5.6 lenses; a Kahles 10 × 42 binoculars was used for species identificatlion. On September 23, 2011, observer O. Shpak sighted two whales at 2:40 a.m. UTC (13:40 local time). At that moment, the vessel was 90 km to the west of the northern part of Kotel’nyi Island (New Siberian Islands) and kept westward. The GPS coor dinates for the vessel position at the moment the whales were detected were 76°06.8N and 134°47.5E. The animals were sighted right ahead at a distance of 1.5 km from the vessel and were approaching (mov ing eastward) being close to one another. The precise distance between the individuals was not possible to detect, but their mutual position was assessed as “next to each other.” The weather was good for observa tion: air temperature, 7°С; pressure, 1008 hPa; 50% cloud cover; sea surface state at Beaufort scale, 2; sea SHORT COMMUNICATIONS Observation of the Gray Whale (Eschrichtius robustus) in the Laptev Sea O. V. Shpak, D. M. Kuznetsova, and V. V. Rozhnov Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, 119071 Russia email: [email protected] Received October 16, 2012 DOI: 10.1134/S1062359013090100

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Page 1: Observation of the gray whale (Eschrichtius robustus) in the Laptev Sea

ISSN 1062�3590, Biology Bulletin, 2013, Vol. 40, No. 9, pp. 797–800. © Pleiades Publishing, Inc., 2013.Original Russian Text © O.V. Shpak, D.M. Kuznetsova, V.V. Rozhnov, 2013, published in Zoologicheskii Zhurnal, 2013, vol. 92, No. 4, pp. 497–500.

797

The gray whale (Eschrichtius robustus, Lilljeborg,1861) as an Arctic species with seasonal migration mayserve an indicator for climate changes in the Arctic(Moore and Huntington, 2008). The gray whale ear�lier inhabited the Pacific and Atlantic oceans and theadjacent northern seas; however, by the beginning ofthe 18th century, this species had been extirpated inthe Atlantic (Mead and Mitchell, 1984). In the PacificOcean, two gray whale populations are recognized(LeDuc et al., 2002): Okhotsk–Korean and Chukotka–Californian. The Okhotsk–Korean population spendssummer in the Sea of Okhotsk, while the Chukotka–Californian population summer feeding grounds liemainly in the Arctic between 174° E and 130° W in theBering, Chukchi, and Beaufort seas; there are recordsof the gray whales visiting the East Siberian Sea (Rice,1998). In the summer months of the years with poorice conditions, individual gray whales were sightednear the mouth of the Kolyma River (Bogoslovskaya,2002) and even more westward, “on the approach tothe New Siberian Islands” (Matishov et al., 2000),namely, according to the map scheme in the publica�tion, between 153° E and 158° E. In the fall, theChukotka–Californian population migrates south�ward, crosses the Pacific Ocean, and descends alongthe North American coast to California and Mexico totheir reproduction area; and in the spring these whalesagain cross the ocean to return to the north, to thecoasts of Kamchatka and Chukotka (Swartz et al.,2006).

Recently, the gray whale was again recorded in theAtlantic basin. On May 8, 2010, an individual of thisspecies was observed in the Mediterranean Sea off theIsraeli coast and, three weeks later, near the coast ofSpain. The proposed explanation, supported by manyspecialists, was that this gray whale had entered theMediterranean Sea by the Northern Sea Route(Scheinin et al., 2011). No matter what brought thisgray whale to the Mediterranean, its migration alongthe northern Eurasian coast became possible due to a

considerable reduction in the ice�covered area in theArctic.

In September–October, 2011, a series of observa�tions on marine mammal distribution was conductedunder the White Whale Program onboard theRV Mikhail Somov in the White, Barents, Kara, andLaptev seas.

The observations were conducted from a platformlocated at 18 m a.s.l. At the beginning of each shift, aswell as additionally in the case of changing conditions,the meteorological parameters (cloud cover, pres�ence/absence of precipitation, wind direction andforce) and quality of visibility (sea state according tothe Beaufort scale, presence and position of the sunglare, and general estimate of visibility according tofive�point scale) were recorded. When marine mam�mals were sighted, the species, number, vessel GPScoordinates (using a Garmin 60csx) at the moment ofdetecting animals, distance to the animals, and bear�ing angle relative to the vessel course were recorded, aswell as their behavior when possible. The animals werephotographed with a Nikon D300S camera equippedwith Nikkor 80–200 mm f2.8, 70–200 mm f2.8, 18–200 mm f3.5–5.6 lenses; a Kahles 10 × 42 binocularswas used for species identificatlion.

On September 23, 2011, observer O. Shpaksighted two whales at 2:40 a.m. UTC (13:40 localtime). At that moment, the vessel was 90 km to thewest of the northern part of Kotel’nyi Island (NewSiberian Islands) and kept westward. The GPS coor�dinates for the vessel position at the moment thewhales were detected were 76°06.8′ N and 134°47.5′ E.The animals were sighted right ahead at a distance of1.5 km from the vessel and were approaching (mov�ing eastward) being close to one another. The precisedistance between the individuals was not possible todetect, but their mutual position was assessed as“next to each other.” The weather was good for observa�tion: air temperature, 7°С; pressure, 1008 hPa; 50%cloud cover; sea surface state at Beaufort scale, 2; sea

SHORT COMMUNICATIONS

Observation of the Gray Whale (Eschrichtius robustus)in the Laptev Sea

O. V. Shpak, D. M. Kuznetsova, and V. V. RozhnovSevertsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, 119071 Russia

e�mail: [email protected] October 16, 2012

DOI: 10.1134/S1062359013090100

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swell, 1–1.5 m; the sun glare at 8:00–8:30 o’clockrelative to the vessel course; and total visibilityaccording to five�point scale, 5–. When approachingthe vessel, the whales separated, one of them passedby the portside retaining its previous direction, whilethe other individual turned by 20°–30° and passed bythe starboard at approximately half a kilometer fromthe vessel (Fig. 1).

Athwartships, the former whale was at a distanceof approximately 100 m from the observer and wasphotographed several times. Although the whale’sposition during hyperventilation coincided with thesun glare, and correspondingly, its images were takenagainst a back light, these photos nonetheless allowfor confirmation of its species (Fig. 2). The secondwhale was too far from the observation platform forsufficient quality photography; and only the cloud ofits blow was photographed. In its external appearance(observation with binoculars) and the shape of theblows in photos, the second whale appeared similarto the first individual.

As compared to the other gray whales sighted by theobserver in the Sea of Okhotsk, the one that passed nearthe vessel was darker and had no pronounced light spots(dark uniform coloration is, possibly, an observation arti�fact due to the back light). A poorly noticeable neckdepression, a blow in a shape of a woolpack, and, mostimportantly, the dorsal ridge knuckles, later detected inthe photos, prove that the whale photographed in theLaptev Sea belonged to the species Eschrichtius robustus.All observations allow us to attribute the second individ�ual to this species as well.

The whales reacted to the vessel (hull length, 133 m;the speed at the moment of encounter, 16 km/h) in thefollowing way: the first whale displayed no anxiety,advanced to the vessel, and then passed by its side, sur�facing several times and spouting water while exhaling.The whale’s body condition looked normal (Fig. 2).The second whale, although it deviated from its initialcourse upon the vessel approach and passed by at aconsiderable distance, also surfaced several times

150°0′0′′ E145°0′0′′ E140°0′0′′ E135°0′0′′ E130°0′0′′ E125°0′0′′ E

75°0′0′′

N

150°0′0′′ E145°0′0′′ E140°0′0′′ E135°0′0′′ E130°0′0′′ E125°0′0′′ E

Tiksi

Kotel’nyi Island

0 255 510 1020 kmW

S

N

E

75°0′0′′

N

Fig. 1. The site where gray whales were encountered in the Laptev Sea (denoted with triangle). Arrows show the directions of theirathwartships movement (signs are not scaled).

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BIOLOGY BULLETIN Vol. 40 No. 9 2013

OBSERVATION OF THE GRAY WHALE 799

while athwartships. Thus, the whales’ reaction to thevessel may be regarded as neutral.

This observation is the first documented encounterof the gray whale in the Laptev Sea, which is over500 km farther from the earlier recorded westernboundary of the species penetration, the East SiberianSea (Matishov et al., 2000). It is also interesting thatthis encounter took place at the end of Septemberrather than at the beginning of the Arctic summerwhen several weeks or even months of open water areahead, and the whales may move westward along thecontinent with a low risk. Presumably, in recent years,the trend of an expansion in the summer distributionrange of this species is observed, and the visits of thegray whale to the East Siberian and Laptev seas is nolonger an extraordinary event, while the small numberof encounters may be explained by a very low intensityof the studies in the Arctic.

The described observation conforms well to thehypothesis on the migratory route of the “Mediterra�nean” gray whale along the Eurasian coast via the North�ern Sea Route, and favors an interhemispheric dispersalof marine organisms through the Arctic corridor.

Taking into account the current changes in thedistribution of Arctic and Subarctic species (ACIA,2005), monitoring of marine animals in the Arctic

seas has acquired paramount importance. Thisimplies the presence of qualified observers onboardthe ships cruising along the Northern Sea Route andin the Arctic as well as establishment of a network ofobservers from the staff of polar meteorological andhydrographic stations, supplying of ship crews withdescriptive material for species identification, andstimulation of their interest in studying Arcticfauna.

ACKNOWLEDGMENTS

This work was performed under the White WhaleProgram for studying the beluga whale distributionand migration by the Permanent Expedition of theRussian Academy of Sciences for Studying Animals ofthe Red Book of the Russian Federation and OtherKey Species of Russian Fauna with financial supportby the Russian Geographic Society.

REFERENCES

ACIA (Arctic Climate Impact Assessment), Cambridge,Mass.: Cambridge Univ. Press, 2005.

Bogoslovskaya, L.S., Distribution and numbers of Califor�nian gray whales in Russian waters, Morskie mlekopitayu�shchie Golarktiki. Materialy 2�i Mezhdunar. konf., Baikal,

Fig. 2. A gray whale in the Laptev Sea. The inset shows the dorsal ridge knuckles characteristic of the gray whale.

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Rossiya (Marine Mammals: Proc. 2nd Int. Conf., LakeBaikal, Russia), 2002, pp. 10–15.LeDuc, R.G., Weller, D.W., Hyde, J., Burdin, A.M.,Rosel, P.E., et al., Genetic differences between western andeastern gray whales (Eschrichtius robustus), J. Cetacean Res.Manag., 2002, vol. 4, no. 1, pp. 1–5.Matishov, G.G., Mishin, V.L., and Vorontsov, A.V., Therio�logica survey along the Northern Sea Route in 1999, Dokl.Biol. Sci., 2000, vol. 370, pp. 55–58.Mead, J.G. and Mitchell, E.D., Atlantic gray whales, inThe Gray Whale Eschrichtius robustus, Orlando: AcademicPress, 1984, pp. 33–53.Moore, S. and Huntington, H., Arctic marine mammalsand climate change: impacts and resilience, Ecol. Appl.,2008, vol. 18, no. 2 (Suppl.), pp. S157–S165.

Rice, D.W., Marine Mammals of the World: Systematics andDistribution, Society for Marine Mammals Special Publica�tion no. 4, Lawrence, Mass.: Allen Press, Inc., 1998.

Scheinin, A.P., Kerem, D., MacLeod, C.D., Gazo, M.,Chicote, C.A., and Castellote, M., Gray whale (Eschrich�tius robustus) in the Mediterranean Sea: anomalous event orearly sign of climate�driven distribution change?, Mar.Biodiv. Rec., 2011, vol. 4, p. e28. doi: 10.1017/S1755267211000042

Swartz, S.L., Taylor, B.L., and Rugh, D.J., Gray whaleEschrichtius robustus population and stock identity, Mamm.Rev., 2006, vol. 36, no. 1, pp. 66–84.

Translated by G. Chirikova