GRAY WHALE (ESCHRICHTIUS ROBUSTUS) PHOTO IDENTIFICATION OFF NORTH-EAST COAST OF SAKHALIN IN 2015

Transcription

1 GRAY WHALE (ESCHRICHTIUS ROBUSTUS) PHOTO IDENTIFICATION OFF NORTH-EAST COAST OF SAKHALIN IN 2015 Photo by Yu. M. Yakovlev Yu. M. Yakovlev, O.M. Tyurneva, V.V. Vertyankin, Peter van der Wolf Prepared for: Exxon Neftegas Limited and Sakhalin Energy Investment Company VLADIVOSTOK March 2016

2 TABLE OF CONTENTS INTRODUCTION STUDY OBJECTIVES MATERIALS AND METHODS Methods for Field Studies Laboratory Methods SURVEY RESULTS Field work results Identification of whales and the number of animals Frequency of Sightings and Migration of Identified Whales Between Known Feeding Areas on the shelf of Sakhalin Island The Offshore Area Piltun Area Cow-Calf Pairs Physical condition Condition factor Skin Condition Additional studies and data obtained in Photo identification in the Piltun area in November and December Photo identification in the Vostochny Wildlife Refuge (Sakhalin Island) in November Photo identification in Olga Bay (Kamchatka Peninsula) in August DISCUSSION Migration of Whales Between Sakhalin Feeding Areas Whale Migration between Southeast Kamchatka and Sakhalin Island Whale Migration between Other Areas and Sakhalin Cow-Calf Pairs Physical condition CONCLUSIONS ACKNOWLEDGEMENTS REFERENCES STUDY PARTICIPANTS APPENDIX

3 ILLUSTRATIONS Figure 1: The number of gray whales recorded in the catalog and identified in off the NE coast of Sakhalin Island Figure 2. The percentage of whales sighted in the Piltun and Offshore feeding areas vs. the total number of known whales in (n=168). No whales younger than 4 years were seen in the Offshore area Figure 3. The number of whales sighted in the main feeding areas NE off Sakhalin from 2002 through Figure 4. The ratio of gray whales sighted in the Offshore and Piltun Areas over all years of research ( , n=257) Figure 5. Percentage of Photoidentified Gray Whales within Each Physical condition Class Relative to the Total Number of Whales Recorded during the 2015 Field Season in the Offshore area Figure 6. Percentage of the gray whales identified for each Physical condition class to the total number of whales observed in the Piltun area during the 2015 field season Figure 7. Percentage of the gray whales identified for each Physical condition class to the total number of whales recorded on Sakhalin Island shelf during the 2015 field survey season Figure А1: Locations of Photo identified gray whale encounters north-east off the coast of Sakhalin Island in Figure А2: Locations of Photo identified gray whale encounters off the north-east coast of Sakhalin Island in September for all years of research Figure А3: Conventional borders of gray whales research off the north-east coast of Sakhalin Island

4 TABLES Table 1. Scopes of work completed by vessel-based and shore-based boat teams off Sakhalin Island during the 2015 expedition Table 2. Scope of Photo ID Operations performed off Sakhalin Island in 2015 by three vehicle-based teams Table gray whale identification off Northeast Sakhalin Island by survey teams Table 4. Frequency of Repeat Sightings of Photo Identified Gray Whales (IDW) photographed by five teams off Sakhalin Island in Table 5. Frequency of Repeat Sightings of Identified Gray Whales (IDW) Off Sakhalin Island in Table 6. Sighting Frequency of Cow-Calf Pairs and Calves Encountered without Cows Offshore Sakhalin Island in 2015, with the Assigned Confidence Indices Table 7. Number of whales in subnormal physical condition sighted offshore Sakhalin Island in Table 8. Physical condition of Sakhalin Island Gray Whales in Table 9. Year to Year Comparison of the Physical condition of 2014 Cows and Calves Recorded off Northeast Sakhalin Island in Table А1. Scope of Photo identification work and average sea depth during each mission off Sakhalin Island in 2015 (data from vessel-based and shore-based boat teams) Table А2. Number of gray whales identified off the north-east coast of Sakhalin Island in Table А3. History of encounters with temporary whales Table А Migration of whales between known feeding areas off the north-east coast of Sakhalin Island. Data provided by the vessel-based group of the IBM DVO RAN Table А5. Areas of identified gray whales encountered off the north-east coast of Sakhalin Island based on the results of all expeditions Table А6. Cow-calf pairs and calves without identified mothers recorded during surveys in

5 SUMMARY Photo identification surveys of gray whales (Eschrictius robustus) conducted in 2015 off Northeast Sakhalin Island are an extension of a long-term study begun in 2002 as part of the program to monitor the Sakhalin gray whale (also known as the western gray whales) aggregation with funding from oil and gas companies Exxon Neftegas Limited and Sakhalin Energy Investment Company, Ltd. The long-term collection of data yielded a valuable information on these animals, which use the waters off the northeast coast of Sakhalin as their summer feeding grounds. There was a significant effort to collect gray whale data in Five photo ID groups took part in the field survey. The efforts of the vessel-based team focused primarily in the Offshore area, where 102 whales were observed. In the Piltun area, including the northern deepwater part of the feeding area, the vessel-based team photographed 31 animals. The shorebased boat team observed 44 whales. Three motor vehicle-based teams conducting a photographic survey of the entire coast of the Piltun area sighted 107 gray whales. The joint efforts of all five teams in the Piltun area identified 113 animal animals. A total of 168 whales were sighted in the known feeding areas off the shores of Sakhalin Island. The early start and late end of the field surveys resulted in obtaining data on the use of the Piltun and Offshore feeding areas throughout the entire feeding season. Annual gray whale records depend on the scope of work (effort) and the number of gray whales present in the study area, which varies from season to season. The efforts of the five teams were more intensive that in previous years, which is probably the reason for a higher number of whales observed in 2015 than in previous years. Currently the Sakhalin catalog of gray whales includes 259 fully identified animals. Out of fourteen new whales found during the 2015 expedition, three were adults not previously observed in other regions. From 2002 to 2015, 249 whales were sighted in the Piltun Area, of which 123 had never been observed in Offshore Area. This figure includes calves and juvenile whales. Only 7 whales were sighted exclusively in the Offshore Area. One whale was photographed north of Cape Elizabeth in 2005 and has not been seen since. In all the years of the study, 12 whales have been encountered near Okha, and all of them have also been seen in other areas. 5

6 Additional material was received from other research groups in D. Lisitsyn provided photographs of two gray whales photographed in the waters off the Vostochny wildlife refuge (Sakhalin Island). These animals had never been observed before and were assigned new numbers in the catalog of the Marine Biology Institute of the Russian Academy of Sciences Far East Branch (IBM DVO RAN). Vladimir Vertyankin submitted images obtained in Olga Bay, Kamchatka, for identification. Of the seven whales identified, one had already been sighted off Sakhalin in previous years. Hence, 171 whales from the IBM DVO RAN Sakhalin catalog were observed during the summer-fall feeding season of Observations from 2003 through 2015 show that the physical condition of most of the whales improves during the season. Cow-calf pairs were observed on the Sakhalin shelf only in the Piltun feeding area. The number of the calves varies from year to year. The smallest number observed was 3 calves in 2004, and the largest number was 17 calves in In 2015, 9 cow-calf pairs and 2 unassociated calves (a total of 11 calves) were registered off Sakhalin Island. All calves observed in all the years of the studies were in good physical condition. According to the long-term observations, the break-up of cow-calf pairs usually begins in mid-august and continues until mid-september. 6

7 INTRODUCTION Photo identification surveys, which have been conducted since 2002 to study the status of the population and develop appropriate measures to mitigate the potential impact on the western gray whale (WGW) population, are one of the most important parts of the gray whale monitoring program. Study of individual animals provides information on population trends and demography, social structure, and other aspects of the life of the animals. On the longer term it also provides information on population status and health. The Photo identification, as a major element of monitoring, substantiates the necessity of impact mitigation management measures and makes it possible to monitor the effectiveness of such measures. More detailed objectives of the Joint Monitoring Program Photo ID studies are summarized below. This report summarizes the results of the gray whale Photo ID studies in 2015 off Sakhalin Island. For discussion of 2015 materials, the team used the historical data (Yakovlev et al., 2014). Study area The studies off Sakhalin Island basically encompass two traditional summer-fall whale feeding areas the Piltun area (52 40 N N), stretching 120 km along the shore of Piltun Bay, where the whales feed primarily at the depths of less than 20 m, and the Offshore area, located further offshore from Chayvo Bay (51 50 N N), with the depths of m (Maminov and Yakovlev, 2002; Yakovlev et al., 2009). 1. STUDY OBJECTIVES The objectives of the western gray whale Photo ID study off Northeast Sakhalin were as follows: 1. To update the Photo ID catalog by photo and video-shooting of each individual WGW; 2. To assess the body and skin condition of individual WGWs; 3. To assess the loyalty of individual WGWs to the feeding areas off Northeast Sakhalin Island; 4. To characterize the WGW population demographics and structure; 5. To characterize the habitat use (i.e., intra- and interannual parameters of migrations 7

8 of individual whales within each feeding area and between the Piltun feeding area, the Offshore feeding area, and other areas); 6. To assess the number, status, health, habitat use, and the annual record of cow-calf pairs separation. This study provides a brief overview of the results of Photo ID efforts in For comparative analysis, this report uses data and results taken from Photo identification reports under the auspices of the Joint Monitoring Program submitted annually to the Ministry of Natural Resources of Russia, the Federal Natural Resources Use Inspection Service, and the Federal Fisheries Agency (Yakovlev and Tyurneva, 2003, 2004, 2005, 2006, 2008; Yakovlev et al, 2007, 2009, 2010, 2011, 2012, 2013, and 2014). For more data see these reports and the tables listed in Appendix A. 2. MATERIALS AND METHODS 2.1. Methods for Field Studies The primary material for the Photo identification of gray whales E. robustus was collected in two areas off Sakhalin Island from June 1 through October 31, 2015 (Figure A1 in Appendix). The 2015 materials were collected by five Photo ID teams. One team operated from the Igor Maksimov Research Vessel, and four teams operated from permanent camps on the coast. One onshore team used inflatable boats, and three moved along the shore in motor vehicles taking shots of the whales they encountered. Apart from those described above, other materials were obtained during later phases of the feeding season. The onshore vehicle-based group headed by Peter van der Wolf performed photo ID work in the Piltun Area from November 20 through December 1. The details of the field studies by the vessel-based Photo ID team are presented in the annual report (Yakovlev et al., 2013a). Whales were photographed in the Piltun and Offshore feeding areas from June 26 through October 27, The whale Photo ID work by the vesselbased team was performed on board a Zodiac boat using a Honda 60 hp 4-stroke outboard motor. A Nikon DSLR D610 camera with an AF-S Nikkor mm F G zoom lens was used for still pictures. High resolution JPEG images were recorded on SanDisc Extreme Pro SD 8

9 HC1 32 Gb 95Mb/s class 10 memory cards. A Nikon DSLR D800 with a Nikkor mm F 2.8 lens was used for video recording. All photo ID work in the Piltun Area was done between ' N in the south and ' N in the north, and between ' E in the west and ,867' E in the East (see Appendix, Figure А1). The methods used by the onshore-based group operating from boats were developed during the photo ID work in Olga Bay off the Southeast Kamchatka peninsula and has been described in full detail in annual reports (Yakovlev et al., 2011 & 2012). For work on Sakhalin Island in 2015, the team used two 5.3 m long Zodiac inflatable boats with hard decks equipped with Yamaha-50 4-stroke outboard motors with steering control. One boat was used for the WGW photography survey itself, and the other one kept steadily a distance of m from the first boat assuring safety. The team followed all safety precautions described in the Procedures developed by the Company specialists. The boats were allowed to move maximum up to 5 km from the shore and up to 20 km to the south and north from the mouth of Piltun Bay. The shore-based boat team studied the waters of the Piltun area within the latitudes ' N on the south and ' N on the north and the longitudes E on the west and E on the east. 1 When several boats were in the sea at the same time the shore-based team suspended its mission and returned to the boat base in order to avoid work in areas near other teams. All Photo ID team supervisors maintained a regular contact with each other to coordinate actions and avoid duplication of effort. The photo-survey teams used the technique applied by the vessel-based team (Yakovlev et al., 2012). The whale photographs were taken with a Canon 7D digital camera equipped with a Canon EF mm F1:4-5.6 L IS USM telephoto lens (with image stabilization). The photographs were recorded at a high resolution setting in large JPEG format. All digital photos of whales were transferred from CF SanDisk 4GB 30 Mb/s memory cards to a computer and then backed up to external disks (at least 3 digital data storage media were used). The information recorded on paper forms was entered into Microsoft Access database and archived. All data were recorded on waterproof paper sheets and entered into a laptop computer at the end of 1 Coordinates of the boat s positions recorded at the extreme points of the water area studied. 9

10 each Photo ID mission. Onshore vehicle-based photo ID work was performed from June 1 through October 31 as part of the 2015 Joint Gray Whale Monitoring Program. Previously, in 2011, 2013, and 2014, the researchers conducted pilot surveys to check feasibility and efficiency of such an approach. They resulted in the development of a full-scale onshore vehicle-based photo ID work program. Onshore vehicle-based Photo ID operations were performed in the southern and northern parts of the Piltun feeding area and covered an area between ,681' N in the south and 53 26,134' N in the north and between E in the west and E in the east (Figure А1). 2 The northern vehicle-based Photo ID team operated from the Odoptu camp in the central part of Piltun Bay. The first southern team was based in the Chayvo camp, and the second one, in the field camp situated near the southern end of Piltun Bay. The teams worked almost every day. Every team included a driver, a photographer and a data recorder, and used a Toyota Land Cruiser 4x4 to move around. The teams also had a VHF radio, Iridium satellite phone, and a GSM mobile phone for communication with the camp, the onshore teams that studied the whales distribution and the team which operated from a boat near the shore. Vehicle-based photo ID missions were completed under favorable weather conditions: visibility over 500 meters, wind force up to 5 per Beaufort scale. A mission started with recording time, sea state, wind force and direction, water and air temperature, atmospheric pressure, and water level (low / high tide). Missions were tracked using GPS from beginning through end. While on a mission, a vehicle moved along the coast line at an average speed of 25 km/hour. The vehicle stopped near the shore at random intervals and the team watched the water area for whales. The team surveyed the water surface with the use of Fujinon 7x50 and Leica 8x32 binoculars to detect the presence of whales. If the team noticed a whale or a pod, they recorded the GPS coordinates of their location from which the whales were spotted and estimated the distance to them and azimuth. If any whales were seen near the shore, the vehicle stopped at a distance of 500 meters and the engine was shut down. The team approached the shoreline on foot in the direction of the whales sighted or waited for the lone whale or pod to swim closer. A Gitzho Studex tripod 2 Estimated coordinates of the locations of whales within the observation area. 10

11 with a Manfrotto 135 Fluid Head was used. The Nikon DSLR D7000 camera was outfitted with a Sigma 5.6 APO EX DG AF mm zoom lens. In some cases, a Sigma 2X teleconverter was attached to extend the zoom power. The team used a Nikon DSLR D610 camera with Nikkor mm lens and a Nikon DSLR D90 as a second camera and a spare camera body. The camera made high-resolution (4928 х 3264) photographs that were saved in JPEG format on a Toshiba 32GB HC1 30 Mb/s class 10 memory card and a SanDisk Extreme 32GB HC1 80 Mb/s class 10 back-up flash drive. Sometimes the team would take a high-resolution video with a Nikon DSLR D7000 camera, but only after taking a full series of photos of spotted animals, pods or cow-calf pairs. The onshore vehicle-based photo ID team headed by Peter van der Wolf used the following equipment: Nikon DSLR Sigma F / DG OS HSM, Nikon DSLR Sigma 5.6 APO EX DG AF mm, Nikon DSLR Nikkor mm F / D Vr and Tamron SP mm F / Di VC USD. Gitzho Studex tripods with Manfrotto 135 Fluid Heads and Manfrotto video tripods with Manfrotto 504HD video heads were used. All the teams recorded and saved data following a common procedure. During the work a field catalog was compiled, which included daily photographs of individual whales made during each mission. The catalog was used to assess the total number of individual whales photographed in coastal waters and perform a preliminary identification Laboratory Methods In lab processing of the photos, each picture obtained during the season is studied for the purpose of linking it with a specific animal. In this case, standard photo ID methods were used which are described in Special Issue No. 12 of the International Whaling Commission (Hammond et al., 1990). After all the pictures have been identified and supplied with a detailed description of the animal and its catalog number, the best photos for each whale that could best describe this whale were selected. Each whale encountered for the first time is assigned a new catalog number. Afterwards all the data are entered into the data base, which makes it possible to extract any information on a specific animal, for any observation period, and on pods in each of the studied areas. A catalog of identified animals is prepared for each study year and is used as the basis for compiling a Master Catalog that is annually updated. The whale identification proce- 11

12 dure was described in detail by Yakovlev et al. (2013a). 3. SURVEY RESULTS 3.1. Field work results Field photo identification of gray whales by the RV Igor Maksimov vessel-based team was performed from June 26 through October 27, Photo identification was performed off Northeast Sakhalin, in the Piltun and Offshore feeding areas, and in the in-shore water area abreast of Chayvo Bay (See Appendix, Figure A1). The shore-based boat team began work on August 1 and ended work on September 30, Photo identification was performed in an area adjacent to Piltun Bay and was mainly concentrated around the bay mouth (see Appendix, Figure A1). For general information about the scope of work performed by the vessel-based and shore-based boat teams see Table 1 herein and Table A1 in the Appendix. Table 1. Scopes of work completed by vessel-based and shore-based boat teams off Sakhalin Island during the 2015 expedition Area of operations Work days Vessel-based team Number of missions Number of groups Number of whales Work days Shore-based boat team Number of missions Number of groups Number of whales Piltun Offshore Total The duration of the mission, the number of whale sightings during the mission, the number of observed whales in a group, the duration of each sighting, etc., were recorded in the respective field of the field data base (Table A1 in the Appendix). For general information about the onshore vehicle-based team efforts and the animals registered see Table 2. Area of operations Table 2. Scope of Photo ID Operations performed off Sakhalin Island in 2015 by three vehicle-based teams Northern vehicle-based team Southern vehicle-based team 1 Southern vehicle-based team 2 Number Number Number Number Number Number Number Number Work Work of missions whales sions groups whales sions of of mis- of of of mis- of of groups days days groups Work days Piltun Number of whales 12

13 Detailed descriptions of the study areas were given in the reports for the previous years. Two teams that operated from boats recorded 694 whales including repeated sightings in the Piltun area (field data). Vehicle-based teams photographed 1261 animals including repeated encounters (field data). For whale sighting points see Figures A1 and A2 in the Appendix. The vessel-based team recorded 465 whales in 23 days of work in the Offshore area (field data). A total of 76,668 photographs were taken during the 2015 field season. The total number of whales recorded by five teams, including repeated sightings of the same whale during different missions, amounted to 1, See Table А1 in the Appendix for the data on the areas and scope of work, as well as for other survey parameters. Depth measurements were taken during boat surveys at the places of whale encounters in the Offshore and Piltun areas Identification of whales and the number of animals The photographs taken during the 2015 expedition were processed and compared with the photographs of past years. Not only the information relating to new whales is of particular interest, but also the data pertaining to whales that were identified in previous years, since combining these data accumulates a more extensive and detailed information about individual animals. Data regarding the number of whales identified off Northeast Sakhalin Island in are presented in Figure 1 and in Table А2 in the Appendix. 3 A different estimate of the whales recorded was used for subsequent analyses. If a whale was recorded by two teams at the same time, the sighting was considered a single sighting. 13

14 Figure 1: The number of gray whales recorded in the catalog and identified in off the NE coast of Sakhalin Island. Compiling the annual and the master WGW catalogs is one of the tasks of the Photo ID operations. The quality of the gray whale identification in subsequent encounters is contingent upon the completeness of the documented aspects. The catalog does not have images of all four aspects for every whale (i.e. the right side, the left side, the dorsal and the ventral surfaces of the fluke). The likelihood of obtaining a complete coverage of all four aspects of each whale increases each year as more photographs are added to the catalog. Along with the Master Catalogs, a record is also kept of the whales whose photographs are not definitive enough to assign a permanent number. This is done for adding them to the catalogs later, after complete data is obtained on these whales, without losing the information on the histories of encounters with them. After the number of a transient whale is determined, it is added to the catalog for the year in which it was first encountered. Information on transient whales is given in Table A3 in the Appendix. The master catalog of gray whales registered off Sakhalin Island currently contains photographs of 257 whales including the dead whale KOGW126 (see Table А2 in the Appendix). 14

15 3.3. Frequency of Sightings and Migration of Identified Whales Between Known Feeding Areas on the shelf of Sakhalin Island Mostly the same animals come to Sakhalin every year for feeding. Some of these whales are recorded for several times during a season and in different years, while others were observed only once within a long time or are new for the catalog. When we analyzed data on return of known individual whales, we assumed that due to the fact that researchers cannot register all whales that come here for feeding we should consider as regularly sighted only those animals which are recorded in maximum three-year intervals. As a result, we distinguished a group of 167 whales that regularly come for feeding to the waters off Northeast Sakhalin Island. Sixteen whales were recorded in this area at intervals greater than three years, therefore this group was classified as rarely sighted whales (Table A5). There were 59 animals that were recorded once during the period from 2002 through 2015 (36 of them were recorded as calves) (Table A6). 4 A total of 768 whales, including repeat sightings of 168 individual whales, were identified from the whales photographed by five teams off Sakhalin Island during the 2015 season (Table 3 and Table 4). Table gray whale identification off Northeast Sakhalin Island by survey teams Vessel-based team Shore-based team Vehicle-based teams Total Area of operations Whales identified including repeated encounters Total whales identified Whales identified including repeated encounters Total whales identified Whales identified including repeated encounters Total whales identified Whales identified including repeated encounters Total whales identified Piltun Offshore Total The animals were observed both in Piltun area along the coast at 8-28 m depths (see the area coordinates above) and in the Offshore area at m depths (see the area coordinates above) (Figure А1 in Appendix). The vessel-based team noted that the feeding group of animals in the Offshore feeding area somewhat moved southeastwardly in 2014 and 4 Fourteen new whales identified in 2015 were not counted as they were seen once only. 15

16 2015 (Figure A2). Table 4. Frequency of Repeat Sightings of Photo Identified Gray Whales (IDW) photographed by five teams off Sakhalin Island in Number of an individual whale sightings (А) Number of whales with this number of sightings (B) Total: Total number of whale sightings (A x B) Total was The average number of sightings per whale (sighting frequency) for the 2015 season Table 5. Frequency of Repeat Sightings of Identified Gray Whales (IDW) Off Sakhalin Island in Year Number of whale sightings Number of IDWs per year Average number of IDW sightings For the season 1,40 1,88 2,38 3,28 3,18 5,40 2,81 2,68 1,95 2,12 2,60 1,85 4,98 4,57 Whale migration patterns between the coastal (Piltun, including Chayvo) and the Offshore feeding areas have been studied based on repeat sightings of identified animals in 16

17 both areas over the entire survey period of (Figure 3, Figure A2, Tables A4 and A5 in the Appendix) The Offshore Area 465 whales (including repeat sightings) were photographed in the Offshore area in 2015 (Figure 4, Table A4 in the Appendix). A total of 102 individual whales were encountered there, and 55 of them were only sighted in the Offshore Area (i.e. were not recorded in the Piltun Area in 2015) (Figures 3 and 4). During all years of studies the research teams have never recorded any juvenile whales, calves or cow-calf pairs in the Offshore feeding area Piltun Area In the Piltun Area 467 whales were photographed (including repeat sightings) in The total number of individual whales sighted was 113, and 61 of these whales were sighted only in this area (Table A5, Figure 2 and Figure 3). A total of 168 whales were registered in the Offshore and Piltun feeding areas in 2015 (Table 5 herein and Table A2 in the Appendix). Figure 2. The percentage of whales sighted in the Piltun and Offshore feeding areas vs. the total number of known whales in (n=168). No whales younger than 4 years were seen in the Offshore area. 17

18 Figure 3. The number of whales sighted in the main feeding areas NE off Sakhalin from 2002 through Over the 14-year study period ( ) out of the total 259 whales currently included in the IBM DVO RAN catalog, 127 whales that used the Piltun and Offshore feeding areas in the same season and/or in different years were recorded (Figure 4, Table А5). Figure 4. The ratio of gray whales sighted in the Offshore and Piltun Areas over all years of research ( , n=257) From 2002 to 2015, 249 whales were sighted in the Piltun Area, of which 123 had never been observed in Offshore Area. This figure includes calves and juvenile whales. Only seven 18

19 whales were not seen anywhere except in the Offshore area, and 127 whales used both feeding areas (Figure 4). One whale was photographed north of Cape Elizabeth in 2005 and has not been seen since. In all the years of the study, 12 whales have been encountered near Okha, and all of them have also been seen in other areas. Calves and juvenile whales apparently cannot feed at great depths and have always been recorded in the nearshore zone at the depths of 5 to 15 meters. For this reason, we believe that the whale migration between the shallow and the deep-water feeding areas is a normal phenomenon and depends on the availability of food, as well as on the physical abilities of the whales Cow-Calf Pairs Nine cow-calf pairs and two calves without cows were sighted in 2015 (Table 6). The first cow-calf pair was sighted on July 3, and the last one was sighted on September 7. Calves without cows were encountered on several occasions (Table A6 in Appendix), both in the company of other calves mothers and in the calf groups, which is why they could be more confidently identified as calves. As stated in Volume 1, Chapter 3 of the Photo ID report for 2012 (Yakovlev et al., 2013), all mothers and calves were assigned confidence indices. Table 6 summarizes the results of this classification. Seven of the nine identified cows arrived with calves in previous years. Two cows came with calves for the first time (Table А6 in Appendix). Table 6. Sighting Frequency of Cow-Calf Pairs and Calves Encountered without Cows Offshore Sakhalin Island in 2015, with the Assigned Confidence Indices Calf's ID Number in Master Catalog KOGW### Number of survey days Identification Reliability Index* Cow's ID Number in Master Catalog KOGW### Number of survey days (mother with calf) Identification Reliability Index А I А А I A I 19

20 248 4 B A I A I A I B A 007 ** 1 III A 114 ** 1 III Note: * Identification reliability index gradations for calves: A = high; B = medium; C = low. Identification reliability index gradations for mothers: I = high; II = medium; III = low. The scoring system is described in Section 3.5.6, Volume I, 2013 report (Yakovlev et al, 2013). ** The cow was sighted once, and the Identification Reliability Index of her classification as a mother is low. From historic data we know that cow-calf pairs start to break up around mid-august and continue to break up until mid-september. The 2015 observations are consistent with these data, though observers noted earlier break-up of certain pairs in that season with majority of calves separating from their mothers in August. The latest when a cow-calf pair was observed on September 7. According to Table A6 in Appendix, the cows have a calf-bearing interval that varies from year to year, ranging from two to three or more years. 28 females recorded in the IBM DVO RAN Sakhalin Catalog were sighted during the period from 2002 through 2015 with calves in the feeding areas of the Sakhalin and Kamchatka shelf (Yakovlev et. al., 2008, 2009, 2010, 2011, and 2012; Tyurneva et. al., 2009, 2010, 2011, and 2012). 20 of these females were sighted with calves 2 or more times. Due to the fact that we regularly observe calves without mothers, we obviously cannot register all females with calves in the current year. 20

21 3.5. Physical condition Condition factor In 2015 we identified 29 (19.3%) whales in subnormal physical condition, including 9 nursing cows we could identify (Tables 7, 8). All of the calves observed in 2015 were well nourished. Table 7. Number of whales in subnormal physical condition sighted offshore Sakhalin Island in Year Total Identified Whales Total whales in subnormal physical condition Percentage of Total Recorded whales in subnormal physical condition Number of Nursing Cows Recorded in the Given Year % % % % % % % % % % % % ,3% 9 Note: The table includes the data only for the whales whose photographs allowed to assess their physical condition. 21

22 Table 8. Physical condition of Sakhalin Island Gray Whales in 2015 Physical Condition Class Number of Whales in Each Physical Condition Class in 2015 Percentage of Whales in Each Physical Condition Class Recorded in , , , , ,7 Note: - Classes 0 and 1: animals in normal physical condition - Classes 2, 3 and 4, highlighted green, correspond to animals with subnormal physical condition. - If a whale was in poor physical condition at the first encounter but its condition improved in subsequent sightings, we used the condition data recorded during the most recent sighting. The whales identified in the Offshore feeding area early during the observation period starting July 1 had a very good physical condition. General improvement in the physical condition of gray whales in this feeding area was also noted by the end of the observation season. 22

23 Physical Condition Class Figure 5. Percentage of Photoidentified Gray Whales within Each Physical condition Class Relative to the Total Number of Whales Recorded during the 2015 Field Season in the Offshore area. A reliable decrease in sightings of whales in subnormal physical condition was observed in the Piltun area by the end of the observation period (Figure 6). The decrease is explained in part by the fact that a significant number of adults moved to the Offshore area to feed (Figure 3, Table A4 in Appendix). Moreover, the animals that stayed in the Piltun area also improved their physical condition class. Five out of the 9 cows with calves seen in the Piltun area were also seen in the Offshore area in later phases of the research season. Two cows improved their physical condition by the end of the observation period. 23

24 Figure 6. Percentage of the gray whales identified for each Physical condition class to the total number of whales observed in the Piltun area during the 2015 field season. Summarized data on sightings of whales in different physical conditions in the two feeding areas for the entire observation season are presented in Figure 7. 24

25 Figure 7. Percentage of the gray whales identified for each Physical condition class to the total number of whales recorded on Sakhalin Island shelf during the 2015 field survey season. Improved physical condition was noted in 46 whales, including two cows recorded as nursing mothers, during the 2015 field season. In 2015, we were able to track the physical condition of animals that were identified in 2014 as cows with calves. Out of 9 cows that had calves in 2014 five were seen in the Offshore area in July 2015 and had a normal physical condition. Table 9. Year to Year Comparison of the Physical condition of 2014 Cows and Calves Recorded off Northeast Sakhalin Island in 2015 Number of mothers / calves in 2014 Number of mothers / calves in subnormal physical condition in 2014 Number of mothers / calves seen in 2015 out of those seen in 2014 Changes in physical condition, 2015 vs Improvement in physical condition physical Deterioration of condition Mothers Calves Skin Condition One of the WGW health parameters is their skin condition. Over a period of several years we have been recording all cases of deviations. 25

26 In contrast to 2014, when eight whales, including one calf, were recorded to have skin sloughing, in 2015 not a single case of such skin damage was observed Additional studies and data obtained in Photo identification in the Piltun area in November and December During the period from November 20 through December 1, the shore-based vehicle team led by Peter van der Wolf worked for 11 days in the Piltun feeding area. The surveys were conducted in the area between 52 47'13.6" N on the south to 53 09' 50.9" N on the north. A total of 3,403 photographs were sent to the laboratory for analysis. Including repeat sightings, 111 whales were photographed. A total of 19 animals were identified. The catalog numbers of two whales could not be determined due to the poor quality of the photographs. All whales identified had already been seen in the Piltun area in the earlier phases of the 2015 field season. Except for one adult whale (KOGW068), all the animals were young (up to four years), including four calves. The physical condition of all the animals was normal Photo identification in the Vostochny Wildlife Refuge (Sakhalin Island) in November Photographs of two whales taken on November 1 and 2, 2015, in the waters off the Vostochny Wildlife Refuge, were provided by D. Lisitsyn. The whales were sighted for the first time, and they were assigned new numbers (KOGW258 and KOGW259) in the IBM DVO RAN catalog. KOGW259 had a subnormal physical condition (class 2), while the physical condition of KOGW258 was normal Photo identification in Olga Bay (Kamchatka Peninsula) in August Seven whales were photographed in Olga Bay (Kamchatka Peninsula) on August 9, The photographs were submitted by V.V. Vertyankin. Five whales were sighted for the first time and received new numbers in the catalog of gray whales recorded on the shelf off the Kamchatka Peninsula. Two whales were sighted in previous years. One of them (KOGW095) has been recorded repeatedly on the Sakhalin Island shelf. 26

27 4. DISCUSSION 4.1. Migration of Whales Between Sakhalin Feeding Areas Photo ID methods of surveying whale populations are often used to determine the habitat utilization by animals. Tracking the migrations of gray whales during their feeding season may provide answers to certain questions pertaining to the ecology of these animals. The analyses of Photo ID data collected offshore Sakhalin indicate that annual and year to year migration of gray whales occur both within the Piltun and Offshore areas and between these areas. From 2002 to 2015, 249 whales were sighted in the Piltun Area, of which 123 had never been observed in Offshore Area. This figure includes calves and juvenile whales. Only 7 whales were sighted exclusively in the Offshore Area. One whale was photographed north of Cape Elizabeth in 2005 and has not been seen since. In all the years of the study, 12 whales have been encountered near Okha, and all of them have also been seen in other areas. Whale migrations have also been discovered in areas further north and south than the tradition feeding areas off Sakhalin, as well as off Kamchatka (Yakovlev and Tyurneva, 2008; Tyurneva et al., 2010; Tyurneva et al., 2010, 2011; Yakovlev et al., 2012). A continuous longterm monitoring is needed to track these geographical migrations (Meier et al., 2007; Vladimirov, 2005, 2006, 2007, 2008 а,b). As shown above, the information about the whales migration between areas over the course of a single season can only be provided by repeat sightings with individually recognized whales during the season. Lone gray whales were observed in one area during the season. Similarly, lone gray whale sightings in one area during a season with re-sightings of the same animal in another area in subsequent years provide information about the year to year migrations. The frequency of sightings over the entire survey period is another important factor in studying whale migration among different areas. In 2015 the effort of five teams resulted in obtaining a significant volume of materials and the average value of individual whales sightings (4.57) was higher than in the previous years, except 4.98 in This enabled us to assess in more detail the way adults and cow-calf pairs use the feeding grounds. One of the benefits of a long-term monitoring program is that with an increasing duration of the study, the same animals continue to be photographed over time, resulting in more sighting data allowing for a more robust analysis of whale migration patterns and the feeding areas utilization. 27

28 4.2. Whale Migration between Southeast Kamchatka and Sakhalin Island Out of all whales identified in the areas studied off Southeast Kamchatka in 2004 and , 52.8 % (85 out of 161) were also photographed in different areas off Sakhalin Island. It is likely that these whales belong to the same feeding aggregation. It is not clear yet if the other 76 animals (47.2%) sighted offshore Kamchatka belong to that aggregation Whale Migration between Other Areas and Sakhalin Seasonal changes in the whale distribution have been described in numerous studies and are considered a reaction to seasonal variations in habitat and the varying distribution of the food supply components (Payne et al., 1986, Calambokidis et al. 1989, Calambokidis et al. 1990, Calambokidis and Quan 1997, Weinrich et al.1997, Wilson et al. 1997, Forney and Barlow 1998, Karczmarski et al.1999). For example, eastern (Chukotka-California) gray whales feeding along the west coast of Vancouver Island, Canada, rotate feeding grounds and food types both within the summer feeding seasons and year to year as a function of the distribution and abundance of their food supply (Bass, 2000; Dunham and Duffus, 2001, 2002; Meier, 2003; Nelson et al., 2008). The distribution of eastern gray whales along the west coast of North America is variable both during a year and year to year with whales using areas from northern California to the Beaufort Sea from spring till autumn, involving significant migration of animals between habitats during a year and year to year (Calambokidis et al. 2002). In recent years, gray whales have been sighted more frequently in the Beaufort Sea, where encounters were rare as far back as 20 years ago (Stafford et al., 2007). The waters off Northeast Sakhalin and Kamchatka are two parts of the historical feeding range of the western gray whale population. According to the historical records, the area of the western gray whale population in the Sea of Okhotsk included Sakhalin Bay (to the west of the northwest tip of the island), the Akademiya and Tugursky Bays south of the Shantar Islands (at the far west end of the Sea of Okhotsk, west of the Sakhalin Island northwest coast), off Northeast Sakhalin, the Shelikhov Bay, Gizhiginskaya Gulf and Penzhinskaya Gulf in the southeastern part of the sea, as well as the waters offshore western Kamchatka (Sleptsov, 1955; Krupnik, 1984; Yablokov and Bogoslovskaya, 1984; Reeves et al., 2008). In 2006 in the Kekurny Bay and Babushkin Bay in the north part of the Sea of Okhotsk, three gray whales were identified and were assigned catalog ID numbers prefixed with NOGW 28

29 (Vladimirov et al., 2007). In 2007 one of these, whale NOGW003 was sighted in the Piltun area (five sightings) and was given the catalog ID number KOGW160 (Table А5 in Appendix). Whale NOGW001/KamGW024 registered for the first time in Kekurny Bay (Sea of Okhotsk) and seen in subsequent years in Olga Bay (Kamchatka) was identified off Sakhalin Island in 2011 and received number KOGW190. In 2008 in the Zakatny Bay offshore Shiashkotan Island, located near the center of the Kuril Islands chain, a joint survey between the Pacific Institute of Bioorganic Chemistry (PIBC FEB RAS) and IBM DVO RAN produced photographs of the whale that was recorded in 2007 in Olga Bay off Kamchatka. It was later seen in Olga Bay in the same season of One gray whale that was previously registered in Olga Bay and off Sakhalin Island in 2007 was identified near Medny Island (Komandorski Islands). Until 2012, every year whales were recorded visiting both the Sakhalin and Kamchatka areas during the same season and/or during previous seasons (Yakovlev et al., 2011). One of the seven whales photographed in Olga Bay (Kamchatka) was seen multiple times off Sakhalin Island in Over all the survey years, 85 gray whales have been identified (32.8% of all known Sakhalin whales and 53.1% of all known Kamchatka whales) that have visited both the Sakhalin and Kamchatka offshore areas in different years or in the same season. This proves that the gray whales migrate between NE Sakhalin and Kamchatka both within one feeding season and between seasons. Satellite tagging of gray whales performed by a team of Russian and foreign scientists in the Piltun area off Sakhalin Island showed the fall migration of satellite-tagged whales to the western coast on North America (See Volume I, Introduction) (Rozhnov et al., 2011). A comparison of the gray whale catalogs of Sakhalin Island and the catalogs of the west coast of the United States and Mexico also showed that some western gray whales visited offshore areas historically occupied by eastern gray whales (Urban et al., 2012, 2013). Two gray whale cows that had been photographed in California, Mexico (IBM KOGW 108, South Piltun I-LOL-M, Ojo de Liebre 2013, and IBM KOGW South Piltun I-BIS-M, San Ignacio, 2011) were also photographed in Piltun area in the 2015 season. 29

30 4.4. Cow-Calf Pairs Our observations indicate that calves are weaned in the period from July through September. According to the data obtained by Bogoslovskaya (1966) for the gray whales in the offshore waters of the Chukotka Peninsula, the demographic differentiation in the groups starts in July and August, when calves leave their mothers and gather in groups in the shallowest waters that are rich in food. Shore vehicle-based distribution surveys conducted in 2005 (Vladimirov et al. 2006) indicated that separation of cow/and calf pairs was completed by early September, with the latest cow-calf pair recorded from the shore on September 11. In 2009, data provided by the vessel-based and shore-based photo identification teams indicate that the latest pair recorded on the shelf of Sakhalin Island was encountered on September 19. In 2014 one cowcalf pair was observed until September 30. In 2015 the latest cow-calf pair was sighted on September 7. Until 2008, the shallow-water Piltun area on the shelf of Sakhalin Island was considered to be the only feeding ground for the cow-calf pairs. However, a cow-calf pair was seen in Olga Bay off Eastern Kamchatka in This mother was recorded with calves on the shelf of Sakhalin Island in previous years (Tyurneva et al., 2010). The research conducted off the Kamchatka Peninsula in earlier than in previous years revealed that mothers with calves also used Olga Bay for feeding (Yakovlev et al., 2011). The cows identified in Olga Bay included both previously known cows from the Sakhalin catalog and those that had not been seen off Sakhalin Island. Migrations of calves and mother-calf pairs from Olga Bay to the Piltun area within a single season were registered (Yakovlev et al., Tyurneva et al., 2012) Physical condition During the winter migration the gray whales cover great distances, and probably exhaust their reserves of energy by the end of the spring migration, which might be a factor in the presence of emaciated whales, especially at the beginning of the season. Studies of the food supply of the gray whales that feed off the coast of Sakhalin revealed that the Piltun Area and in particular the Offshore Feeding Area are rich sources of food (Fadeyev, ). Some whales that showed signs of emaciation in previous years did not exhibit such signs in subsequent years. This seasonal ability of emaciated whales to regain their physical condition had also been observed previously (Yakovlev and Tyurneva 2003 and 2013; Ya- 30

31 kovlev et al. 2007; Weller et al. 2004). The energy value of the gray whales food when combined with fasting and feasting cycles related to migrating, feeding, and breeding, is a dynamic process. At this point, recovery and deterioration of the physical condition of both nursing and non-nursing whales still elude full explanation based on the available data. Skin sloughing was noted in some animals in Observations of these whales in based on the photographs indicate that skin sloughing recorded in 2003 and 2014 does not seem to have any noticeable long-term effect on the external physical condition of the whales. So far, the phenomenon of skin sloughing remains unexplained, but the researches believe that it may be a result of several factors such as suppressed immunity, diseases caused by bacteria, viruses, fungi (Gaydos et al. 2004), internal or external parasites (Dailey et al. 2000), pollution, or excessive exposure to fresh water. The observed cases of skin sloughing showed that the skin recovers quickly after sloughing, and no subsequent pathological consequences were recorded on the surface of the whales skin (Tyurneva and Yakovlev 2005c; Tombach Wright et al. 2007). Appearance of white patches, recorded on some gray whales since 2005, has yet to be explained. Continued Photo ID monitoring of these animals has not resulted in any conclusions about the effect of the white skin patches on gray whales. To date no obvious health effects have been tied to them, but as this phenomenon is poorly understood, it is essential to continue observation of all known animals afflicted with white patches. 5. CONCLUSIONS 1. Two main feeding areas have been discovered off Northeast Sakhalin: a shallow area adjacent to Piltun and Chayvo Bays and a deep water Offshore area. 2. Every year mostly the same individual whales return to feed to the coast of Sakhalin. Some of these whales are recorded several times during one season and in different years, whereas others are not seen again for a long time or are new to the catalog (i.e. are sighted for the first time). A group of 167 whales was identified that come to the waters off Northeast Sakhalin Island regularly for feeding. Sixteen whales were recorded in this region at intervals greater than three years, and this group was classified as rarely sighted whales (Tables A2 and A5). There were 59 animals that were recorded once during the period from 2002 through 2015 (36 of them were recorded as calves). 31

32 3. Currently the Sakhalin catalog of gray whales includes 259 fully identified animals. Of 14 new whales found during the 2015 expedition, three were adults and had not been sighted in other regions in previous years. Two whales photographed at the Vostochny refuge (Sakhalin Island) had not been recorded before and received new ID numbers in the IBM DVO RAN catalog. 4. The number of registered whales depends both on the scope of the studies (efforts), and on the number of whales present in the study area, which varies from season to season. 5. A total of 168 individual whales were sighted in the feeding areas off Sakhalin in This number is greater than any of the numbers in the previous years, but the five teams had also exerted more effort. 6. Due to the additional data obtained from other areas (Vostochny Wildlife Refuge at Sakhalin Island, and Olga Bay on Kamchatka), the total number of whales recorded in the IBM DVO RAN catalog and identified in 2015 was 171 whales. 7. In 2015, 102 animals were identified in the Offshore area off the northeast coast of Sakhalin Island, of which 55 were sighted only there. In the Piltun feeding area, three teams recorded 113 whales, of which 61 were observed only in the Piltun area; 47 animals used both areas for feeding gray whales were recorded only in the Piltun area from 2002 through 2015, this amount includes calves and juvenile whales. Only 7 whales have not been seen anywhere outside the Offshore area. Out of the total number of whales (257) registered in the Piltun and Offshore feeding areas during all observation seasons, 127 whales used both feeding areas both in a single season and in different years. Using all available feeding areas offshore Sakhalin is the usual behavior of gray whales, both within one season, and in different seasons, aimed at optimizing the utilization of the ever-changing distribution of food resources. 9. It was established that most whales improve their physical condition during the feeding season. All calves observed during all study years had a normal physical condition (Class 0) whales (including 9 lactating females) were identified with inadequate physical condition in 2015, which was 19.3% of the total number of animals whose photographs allowed to assess their physical condition (150 whales). Good physical condition was seen in whales sighted in the Offshore area early during the observation period. 32

33 11. Cow-calf pairs were recorded on the Sakhalin shelf only in the Piltun area, but never in the Offshore area. In 2008 we established that Piltun area offshore Sakhalin is not the only place for feeding of cow-calf pairs, and at least one other area is located in Olga Bay (Kamchatka). 12. The number of the calves varies from year to year. The minimum observed number was three calves in 2004, and the maximum number was 17 calves in cow-calf pairs and 2 unassociated calves (a total of 11 calves) were registered off Sakhalin Island in Two cows, identified as mothers with calves, were observed for the first time with a calf. Calves unaccompanied by mothers were seen close to the identified pairs and in groups of calves. 13. According to the long-term observations, the break-up of cow-calf pairs usually begins in mid-august and continues until mid-september. 14. In some years gray whales with sloughing skin were registered. Long-term observations have shown that it is a short-term phenomenon that disappears within a few days. No whales with sloughing skin were seen in Besides those two feeding areas off Northeast Sakhalin, gray whales were also recorded: near Cape Elizabeth; north of Okha; off the east coast of Kamchatka (Halatyrsky beach, Vestnik Bay and Olga Bay, and near Karaginsky Island); near the Komandorski Islands (Zakatnaya Bay, Medny Island); near the Kuril Islands (Shiashkotan); near the Vostochny Wildlife Refuge (Sakhalin Island). 16. Seven whales were photographed in Olga Bay of Kamchatka in Two of them had been seen before in Olga Bay and have numbers assigned to them in the Kamchatka Catalog. Five of those were new to the catalog. Kamchatka gray whale catalog contains photos of whales encountered in three areas (Khalaktyrsky beach, Vestnik Bay and Olga Bay) in 2004, and To date this catalog contains 161 identified animals, of which 85 animals were also photographed on the shelf of Sakhalin in different areas and in different years of surveys, and possibly most of them belong to the same feeding aggregation of gray whales. The affiliation of the other 76 animals found at Kamchatka, which do not belong to the Sakhalin catalog, remains unclear. 17. During the same season gray whales can use feeding grounds both along the coast of Kamchatka and on Sakhalin shelf. 18. Observations during the late dates of the feeding season (November December) 33

34 showed that a few of the juvenile whales stayed in the Piltun area. All of them had a normal physical condition. 6. ACKNOWLEDGEMENTS We are especially grateful to Exxon Neftegas Limited and Sakhalin Energy Investment Company for support and funding for this study. The Photo ID studies were made possible thanks to the participation of the scientific staff and crewmembers of the base vessels used by the Photo ID team. We would especially like to thank MMO for provision of data on WGW distribution and migrations and this data transfer to Zodiak during the Photo ID activities, as well as Ye.P. Shvetsov, K.А. Drozdov, A.Yu. Yakovlev, O.A. Miroshnikova, and S.Yu. Neznanova for data processing assistance. We would like to thank Lisanne Aerts (LAMA Ecological), and Christina Tombach- Wright (LGL Limited) for project preparation; Yury Bychkov (LGL Limited) for technical support in setting up and maintaining the database; I. Zhmayev and S. Yazvenko(LGL Eco) for coordination of activities; Mike Swindoll (ENL) for providing valuable comments and editing revisions; and other specialists of Exxon Neftegas Limited and Sakhalin Energy Investment Company who were part of this work from 2002 through 2015 for their support and for arranging the expeditions. 34

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38 Whale (Eschrichtius Robustus) Population Off Northeast Sakhalin Island in Russia, p. Unpublished Contract Report for Exxon Neftegas Limited, Yuzhno- Sakhalinsk, Russia. Brownell, R.L. and D.W. Weller Is the Carrying Capacity Hypothesis a plausible explanation for the skinny gray whale phenomenon? Int. Whal. Comm. Sci. Comm. Rep. SC/53/BRG p.(unpublished). Calambokidis, J., J.D. Darling, V. Deecke, P. Gearin, M. Gosho, W. Megill, C.M. Tombach, D. Goley, C. Toropova and B. Gisborne Abundance, range and migrations of a feeding aggregation of gray whales (Eschrichtius robustus) from California to southeastern Alaska in J. Cetacean Res. Manage. 4(3): Dailey, V.D., F.M.D. Gulland, L.J. Lowenstine, P. Silvagni and D. Howard Prey, parasites and pathology associated with the mortality of a juvenile gray whale (Eschrichtius robustus) stranded along the northern California coast. Diseases of aquatic organisms. V.42, p Dunham, J. S. and D.A. Duffus Foraging patterns of gray whales in central Clayoquot Sound, British Columbia. Mar. Ecol. Prog. Ser. 223: Dunham, J.S and D.A. Duffus Diet of gray whales (Eschrichtius robustus) in Clayoquot Sound, British Columbia, Canada. Mar. Mamm. Sci. 18(2): Jones, M.L. and S.L. Swartz Gray whale Eschrishtius robustus. In book: Encyclopedia of Marine Mammals. Eds. W.F. Perrin, Wursig B. and J.G.M. Thewissen. Academic Press, P Gaydos, J.K., Balcolb K.C., III, Osborne, R.W, and Dierauf L Evaluating potential infections disease for southern resident killer whales, Orcinus orca: a model for endangered species. Biol. Cons. V. 117, p Hammond, P.S., S.A. Mizroch and G.P. Donovan Animal recognition of cetaceans: use of Photo ID and other techniques to estimate population parameters. Report of the Int. Whal.Comm.Special Issue p. Karczmarski, L, V.G. Cockcroft, and A. McLachlan Group size and seasonal pattern of occurrence of humpback dolphins Sousa chinensis in Algoa Bay, South Africa. South African Journal of Marine Science. Vol. 21 p

39 Krupnik, I. I Gray Whales and the Aborigines of the Pacific Northwest: The History of Aboriginal Whaling. p In: Jones, M. L., Swartz, S. L. and Leatherwood, S. (eds.): The Gray Whale Eschrichtius robustus. Academic Press Inc. LeBoeuf, B.J., H. Perez-Cortes M., U. Urban R., B.R. Mate, and F. Ollervides U High gray whale mortality and low recruitment in 1999: potential causes and implications. J. Cet. Res. Manage. 2: Meier S.K., Yazvenko S.B., Blokhin S.A., Wainwright P., Maminov M.K., Yakovlev Yu.M. and Newcomer M.W Distribution and abundance of western gray whales off Northeastern Sakhalin Island, Russia, Environmental Monitoring and Assessment, V. 134, p Meyer, E.T Socio-technical perspectives on digital photography: scientific digital photography use by marine mammal researchers. Ph.D. dissertation, School of Library and Information Science, Indiana University, Bloomington Indiana, USA. 340 pp. Moore, S.E., Urban R.J., Perryman, W.L., Gulland, F., Perez-Cortes, M.H., Wade, P.R., Rojas Bracho, L., and Rowles, T Are gray whales hitting K hard? Mar. Mamm. Sci. 17: Moore, S.E., J.M. Grebmeier and J.R. Davies Gray whale distribution relative to forage habitat in the northern Bering Sea: current conditions and retrospective summary. Can. J. of Zool. 81: Nelson, T.A., D.A. Duffus, C. Robertson and L.J. Feyrer Spatial-temporal patterns in intraannual gray whale foraging: Characterizing interactions between predators and prey in Clayoquot Sound, British Columbia, Canada. Marine Mammal Science 24(2): Payne, P.M., J.R. Nicolas, L. O Brien and K.D. Powers The distribution of the humpback whale, Megaptera novaeangliae, on Georges Bank and in the Gulf of Maine in relation to densities of the sand eel, Ammodytes americanus. Fishery Bulletin V.84(2), p Reeves, R.R., T.D. Smith, E.A. Josephson Observations of western gray whales by shipbased whalers in the19th Century. International Whaling Commission, Scientific Committee. World Whaling History. SC/60/BRG7, 19 pp. Rozhnov V., Маte B., Bradford A., Vertyankin V., Tsidulko G., Irvine L., Hayslip C., Poltev Yu., Ilyashenko V. and Tyurneva O Preliminary results of program for research of the western gray whale (Eschrichtius robustus) population habitat using satellite telemetry. 39

40 Article SC/63/BRG 26, submitted to the International Whaling Commission, 63 Scientific Committee Meeting, Tromsø, Norway, 30 May 11 June pp. Stafford, K.M., Moore S. E., Spillane M. and Wiggings S Gray whale calls recorded near Barrow, Alaska, throughout the winter of Arctic, 60 (2), Swartz, S.L., B.L. Taylor and D.J. Rugh Gray whale Eschrichtius robustus population and stock identity. Mammal Rev. Vol. 36. N 1. pp Tombach Wright. Ch., Tyurneva, O.Yu. and Yakovlev, Yu.M Anomalous skin conditions recorded on western gray whales Eschrichtius robustus off Northeastern Sakhalin, Russia, Abstract of 17th Biennial Conference on the Biology of Marine Mammals, Cape Town, South Africa. November 29 December 3, Tyurneva O.Yu. and Yakovlev Yu.M Skin sloughing of gray whales Eschrichtius robustus in the Sea of Okhotsk. Abstract the 16 biennial Conference on the Biology of Marine Mammals, San Diego, California, December 12-16, 2005, p Tyurneva, O.Yu., M.K. Maminov, E.P. Shvetsov, V.I. Fadeev, N.I. Selin and Yu.M. Yakovlev Seasonal migrations of gray whales (Eschrichtius robustus) between feeding areas off Northeast Sakhalin Island. In the book: Marine Mammals in the Holarctic. Collection of scientific papers of International Conference Saint-Peterburg, September 10-14, P Tyurneva O.Yu., Yakovlev Yu.M, Tombach Wright C. and Meier S.K The North Pacific Western Gray Whales of Sakhalin Island. Trafford Press, Canada. 195 p. Tyurneva, O. Yu., Yakovlev, Yu. M., Vertyankin, V. V., Gailey, G., Sychenko, O. and Muir, J. E d. Photo Identification of Western Gray Whales (Eschrichtius robustus) off Northeast Sakhalin Island and Southeast Kamchatka Peninsula (Russia), Article SC/62/BRG submitted to the IWC 62 Scientific Committee Meeting, Agadir, Morocco, June pp. Tyurneva O.Yu., Yakovlev Yu.M., Vertyankin, V.V. 2011a. Results of photo identification study of gray whales (Eschrichtius Robustus) off Northeast Sakhalin Island and Southeast Kamchatka Peninsula, Russia, Article SC/63/BRG12, submitted to the International Whaling Commission, 63 Scientific Committee Meeting, Tromsø, Norway, 30 May 11 June P

41 Tyurneva O.Yu., Yakovlev Yu.M., Vertyankin V.V., Gailey G., Sychenko O. 2011b. Discovery of a New Feeding Area for Western Gray Whale (Eschrichtius robustus) Cow-Calf Pairs Off Southeast Kamchatka. Abstracts of the 19th Biennial Conference on the Biology of Marine Mammals. Tampa, Florida (USA), November 27- December 2, P Tyurneva O.Yu., Yakovlev Yu.M., Vertyankin V.V Photo Identification Study of Gray Whales (Eschrichtius Robustus) Off Northeast Sakhalin Island and Southeast Kamchatka Peninsula, Russia: Report SC/64/BRG22 of the Scientific Committee IWC, Panama City, Panama, June P Tyurneva O.Yu., Yakovlev Yu.M., Vertyankin V.V Photo Identification Study of Western Gray Whales (Eschrichtius Robustus) Off Northeast Sakhalin Island and Southeast Kamchatka Peninsula, Russia. Report SC/65a/BRG08 of the Scientific Committee IWC, Jeju, Republic of Korea, 3-15 June P Urbán R.J., Weller D., Tyurneva O., Swartz S., Bradford A., Yakovlev Y., Sychenko O., Rosales H.N., Martínez S.A., Burdin A. and Gómez-Gallardo A.U Report on the photographic comparison of the Western and Mexican gray whale catalogs. Report SC/64/BRG13 of the Scientific Committee IWC, Panama City, Panama, June P Urbán R.J., Weller D., Tyurneva O., Swartz S., Bradford A., Yakovlev Y., Sychenko O., Rosales H.N., Martínez S.A., Burdin A. and Gómez-Gallardo A.U Report on the photographic comparison of the Sakhalin Island and Kamchatka Peninsula with the Mexican gray whale catalogs. Report SC/65a/BRG04 of the Scientific Committee IWC, Jeju, Republic of Korea, 3-15 June P Vertyankin, V.V., V.C. Nikulin, A.M. Bednykh and A.P. Kononov Sighting of Gray Whales (Eschrichtius Robustus) Off Southern Kamchatka. In the book: Marine Mammals in the Holarctic. Collection of scientific papers of International Conference Koktebel, Krimea, Ukraine, October 11-17, P Vertyankin V.V., Vladimirov V.A., Tyurneva O.Yu., Yakovlev Yu.M., Andreev A.V. and Burkanov V.N Sighting of Gray Whales (Eshrichtius Robustus) Off Eastern Kamchatka and in the Northern Sea of Okhotsk, Scientific Committee Papers International Whaling Commission, 59 annual meeting, Anchorage, USA, electronic version SC/59/WP6, 41

42 8 pp. Weller, D.W. and R.L. Brownell Jr Eschrichtius robustus (Asian or Northwest Pacific stock). In: Hilton-Tayler (comp.) 2000 IUCN Red List of Threatened Species. IUCN/SSC, Gland, Switzerland and Cambridge, UK. Weller, D.W., A.M. Burdin, A.L. Bradford, Y.V. Ivashchenko, G.A. Tsidulko, A.R. Lang, R.L. Brownell Jr Western Gray Whales off Sakhalin Island, Russia: A Joint Russia-U.S. Scientific Investigation July-September Unpublished report for International Fund for Animal Welfare and International Whaling Commission by Southwest Fisheries Science Center, La Jolla, CA, Kamchatka Branch of Pacific Institute of Geography, Petropavlovsk, Russia, and the Alaska Sealife Center, Seward, AK. 41 p. Yablokov, A.V. and L.S. Bogoslovskaya A review of Russian research on the biology and commercial whaling of the gray whale. Pages In: M.L. Jones, S.L. Swartz, and S. Leatherwood (eds.) The gray whale Eschrichtius robustus, Academic Press, Orlando, FL. Yakovlev, Yu.M. Tyurneva, O.Yu. and Tombach Wright, Ch Seasonal Migrations of Western Gray Whales Eschrichtius Robustus Between the Feeding Areas Off Northeast Sakhalin Island (Russia) in Asian Fisheries Science. Vol. 22, N 1, P Available online at Yakovlev Yu.M., Tyurneva O.Yu., Vertyankin V.V., Gailey G. and Sychenko O Discovering a New Feeding Area for Calf-Cow Pairs of Endangered Western Gray Whales Eschrichtius Robustus Off Southeast Kamchatka in 2009 and their Utilizing Different Feeding Areas within One Season. Egyptian Journal of Aquatic Research. Vol. 37, 1, P Yakovlev Yu.M., Tyurneva O. Y., Vertyankin V.V Photo Identification of Gray Whales (Eschrichtius Robustus) Off Northeast Sakhalin Island and Southeast Kamchatka Peninsula, Report for Exxon Neftegas Limited and Sakhalin Energy Investment Company Limited, Yuzhno-Sakhalinsk, Russia. P

43 8. STUDY PARTICIPANTS Project Aspects Name Place of Work Field Photography and Videography Offshore Sakhalin Photographer, team leader Yuri Mikhailovich Yakovlev DVO RAN Marine Biology Institute Video camera operator Arseny Yurievich Yakovlev DVO RAN Marine Biology Institute Data recorder Yevgeny Pavlovich Shvetsov DVO RAN Marine Biology Institute Boat Operator Nikolai Ivanovich Prokhorov DVO RAN Marine Biology Institute Photographer, onshore team lead Vladimir Vasilyevich Vertyankin Kronotsky reserve Data recorder Vladimir Vladimirovich Kuznetsov Sakhalin State University Photographers, vehiclebased team leads Peter van der Wolf Yury Gilev Andrey Gribov Geokon, Sakhalin State University Data recorders Maksim Kozlov Aleskandr Chasnokov Vladimir Chernitsyn Elena Solonenko Sergey Dubrovsky Aleksandr Omelyanenko Igor Timokhin Andrey Tishchuk Sakhalin State University Data analysis 43

44 Data processing and analysis, catalog preparation Olga Yuryevna Tyurneva Yuri Mikhailovich Yakovlev IBM DVO RAN Photo identification laboratory, Vladivostok Image processing Arseny Yurievich Yakovlev Olga Nikolayevna Miroshnikova Yevgeny Pavlovich Shvetsov Svetlana Yurievna Neznanova DVO RAN Marine Biology Institute IT and computer support Yevgeny Pavlovich Shvetsov Konstantin Anatolyevich Drozdov DVO RAN Marine Biology Institute Report preparation Report preparation Yuri Mikhailovich Yakovlev Olga Yuryevna Tyurneva IBM DVO RAN Photo identification laboratory, Vladivostok Report Review Sergey Vinogradov Sakhalin Energy 44

45 APPENDIX 45

46 Figure А1: Locations of Photo identified gray whale encounters north-east off the coast of Sakhalin Island in

47 Figure А2: Locations of Photo identified gray whale encounters off the north-east coast of Sakhalin Island in September for all years of research. 47

48 Figure А3: Conventional borders of gray whales research off the north-east coast of Sakhalin Island. 48