North Pacific right whale, Eastern North Pacific Eubalaena japonica

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1 North Pacific right whale, Eastern North Pacific Eubalaena japonica Class: Mammalia Order: Cetacea Conservation Status Heritage Agency G Rank: G1 USFWS/NOAA: Listed Endangered S Rank: S1 SOA: Endangered BLM: USFS: AA: IUCN: Endangered Final Rank Conservation category: II. Red II = high status and either high biological vulnerability or high action need Category Range Status: -0 to 0 10 Biological: -50 to 50.5 Action: -0 to 0 0 Higher numerical scores denote greater concern Status Population Trend (-10 to 10) A reliable trend estimate for the eastern North Pacific stock is currently not available (Angliss and Outlaw 005). Until recently, no juveniles had been detected in the eastern North Pacific population for many decades; however, in October 00, three cow and calf pairs and other individuals were observed in the Bering Sea (NOAA 00). Even with almost complete protection for decades, the eastern North Pacific population remains extremely small with no sign of an increasing population trend (North Pacific Right Whale Recovery Team 00). The relative paucity of sightings virtually everywhere in the 0th century and the pattern of apparent decline observed after the 1960s all point to a situation in which remnant populations may have been slowly recovering from intensive whaling, only to be devastated by illegal soviet catches. Distribution Trend (-10 to 10) Before exploitation, right whales were found in the Gulf of Alaska, eastern Aleutians and south-central Bering Sea (also in the Sea of Okhotsk and Sea of Japan). During , there were only 8 sightings of right whales in the entire eastern North Pacific, with the majority of these in the Bering Sea and adjacent areas of the Aleutian Islands. Most right whales observed in AK currently were concentrated in the SE Bering Sea. Overall, the geographic distribution of the species in the North Pacific was considerably greater in the 19th century than it appears to be in modern times. Current threats are largely unknown, but potentially include inbreeding depression and low population density effects (Allee effect), marine traffic and ship strikes, entanglement in fishing gear, degradation of feeding habitat (e.g., through effects of pollution on zooplankton), human disturbance (e.g., ships and other underwater noisemakers) and climate change and resultant changes in food supply (see North Pacific Right Whale Recovery Team 00). Biological - variables measure the trend in a taxon s population status or distribution. Higher status scores denote taxa with known declining trends. Status scores range from -0 (increasing) to 0 (decreasing). Population Size (-10 to 10) Status Total: - variables measure aspects of a taxon s distribution, abundance and life history. Higher biological scores suggest greater vulnerability to extirpation. Biological scores range from -50 (least vulnerable) to 50 (most vulnerable). Until recently, the eastern North Pacific stock was estimated in the tens of animals (Brownell et al. 001, Tynan et al. 001, North Pacific Right Whale Recovery Team 00). Sixteen to 17 unique whales are known from genetic work and boat/aerial surveys in the SEBS (Shelden, NOAA, personal communication); observations of adults and calves in the SEBS in 00 expanded the known eastern population to at least 5 individuals (NOAA 00). Of 13 individuals photographed during aerial surveys in , one has already been rephotographed, and 5 of 11 genetic samples collected in 1997 and 1999 were repeat samples; this mark-recapture success rate is consistent with a very small population size (LeDuc et al. 001). Wade

2 et al. (011) estimated 31 right whales (95% confidence limits 3 to 5) in the Bering Sea. Brownell et al. (001) suggested from a review of sighting records that the abundance of this species in the western North Pacific was likely in the "low hundreds". Range Size (-10 to 10) Southeastern Bering Sea slope and rarely in the Gulf of Alaska. All detections since 1998 (except for a passive acoustic detection) were in shelf waters adjacent to Kodiak Island. In recent decades, only detections in the Gulf of Alaska came from passive acoustic recorders (Wade et al. 011b). Population Concentration (-10 to 10) Analysis of all known sightings data for this species reveal two known "areas of concentration". The area of densest concentration (91% of all encounters in this area) in the southeastern Bering Sea spreads from roughly east from 173W longitude to 161 W longitude and south from 58N latitude. The other area of concentration is in the Gulf of Alaska and spreads east from 170 W longitude to 150 W longitude and south to 5 N longitude. Reproductive Potential Age of First Reproduction (-5 to 5) Sexually mature between 8 and 10 years. Number of Young (-5 to 5) Females give birth to usually a single calf once every three to five years. Ecological Specialization Dietary (-5 to 5) Zooplankton specialists; primary prey is euphasiids and copepods, gathered by skimming through schools with mouth agape. Habitat (-5 to 5) Until the late 1960s, waters of the southeastern Bering Sea (SEBS) slope and middle shelf, eastern Aleutian Islands, and GOA slope and abyssal plain were important habitat. Since 1980, whales have only been consistently reported on the SEBS middle shelf, although acoustic detections have been reported in the other historical use areas. Until the late 1960s, whales were commonly seen in waters >000 m deep, indicating their distribution was not restricted to the continental shelf. Since 1979, sightings have been in much shallower water (<00 m deep), which may simply reflect the lack of search effort elsewhere. Biological Total: Action - variables measure current state of knowledge or extent of conservation efforts directed toward a given taxon. Higher action scores denote greater information needs due of lack of knowledge or conservation action. Action scores range from -0 (lower needs) to 0 (greater needs). Management Needs (-10 to 10) Listed as endangered under the ESA and depleted under the MMPA; this species is not harvested. In 006, NMFS issued a final ruling designating areas as northern right whale critical habitat, one in the Gulf of Alaska and the other in the Bering Sea. Monitoring Needs (-10 to 10) Aerial and vessel surveys for right whales in the southeastern Bering Sea occur every summer since Research Needs (-10 to 10) Initial large decline due primarily to hunting that occurred through the mid-1930s and lack of population recovery has been attributed to illegal Soviet whaling in the 1960s. Current threats are largely unknown, but potentially include inbreeding depression and low population density effects (Allee effect), marine traffic and ship strikes, entanglement in fishing gear, degradation of feeding habitat (e.g., through effects of pollution on zooplankton), human disturbance (e.g., ships and other underwater noisemakers) and climate change and resultant changes in food supply (see North Pacific Right Whale Recovery Team 00). Survey Needs (-10 to 10) Aerial and vessel surveys for right whales were conducted between 1998 and 000 in a portion of the southeastern Bering Sea where right whales have been observed each summer since 1996 (Goddard and Rugh 1998). North Pacific right whales are observed consistently in this area, although it is clear from historical and Japanese sighting survey data that right whales often -10 6

3 range outside this area and occur elsewhere in the Bering Sea (Clapham et al. 00, LeDuc et al. 001, Moore et al. 000c, Moore et al. 00, NMFS unpublished data in Angliss and Outlaw 006). Bottom-mounted acoustic recorders were deployed in the southeastern Bering Sea and the northern Gulf of Alaska in 1999 to document the seasonal distribution of right whale calls (Mellinger et al. 00). Preliminary analysis of the data from the recorders indicates that right whales remain in the southeastern Bering Sea from May through November with peak call detection in September (Munger and Hildebrand 00). Acoustic monitoring at seven sites in the Gulf of Alaska has detected right whale calls at only two: one off eastern Kodiak and the other in deep water south of the Alaska Peninsula. Right whales have not been observed outside the localized area in the southeastern Bering Sea during surveys conducted for fishery management purposes which covered a broader area of Bristol Bay and the Bering Sea. There are fewer recent sightings of right whales in the Gulf of Alaska than in the Bering Sea (Brownell et al. 001), although little survey effort has been conducted in this region. Waite et al. (003) summarized sightings from the Platforms of Opportunity Program from Seven sightings of right whales were reported, but only one sighting of four right whales at the mouth of Yakutat Bay in 1979 could be positively confirmed (Waite et al. 003). Sightings of a single right whale off eastern Kodiak Island occurred in July 1998 during an aerial survey (Waite et al. 003), and additional singletons were observed in the Barnabas Canyon area from NOAA surveys in August 00, 005, and 006 (NMML unpublished data in Angliss and Outlaw 006). Surveys were conducted in Bristol Bay in 00 where the first sighting of a calf was documented in decades (Waite et al. 003). Action Total: 0 Supplemental Information Harvest: Seasonal Occurrence: Taxonomic Significance: % Global Range in Alaska: >10% % Global Population in Alaska: >5% Peripheral: Range Map - variables do not receive numerical scores. Instead, they that are used to sort taxa to answer specific biological or managerial questions. None or Prohibited Nonbreeding Monotypic species No References Angliss, R. P. and R. B. Outlaw (eds) Alaska Marine Mammal stock assessment reports (SARs). National Marine Mammal Laboratory. Alaska Fisheries Science Center, Seattle, WA. Available online at: 3

4 Angliss, R. P. and R. B. Outlaw (eds) Alaska Marine Mammal stock assessment reports (SARs). National Marine Mammal Laboratory. Alaska Fisheries Science Center, Seattle, WA. Available online at: Baker, R. J., L. C. Bradley, R. D. Bradley, J. W. Dragoo, M. D. Engstrom, R. S. Hoffman, C. A. Jones, F. Reid, D. W. Rice, and C. Jones Revised checklist of North American mammals north of Mexico, 003. Museum of Texas Tech University Occasional Pa Brownell, R. L., Jr., P. J. Clapham, T. Miyashita, and T. Kasuya Conservation status of North Pacific right whales. J. Cetacean Res. Manage. (Special Issue) : Clapham, P. J., C. Good, S. E. Quinn, R. R. Reeves, J. E. Scarf, and R. L. Brownell. 00. Distribution of North Pacific right whales (Eubalaena japonica) as shown by 19th and 0th century whaling catch and sighting records. J. Cetacean Res. Manage. 6:1 Folkens, P. A., R. R. Reeves, B. S. Stewart, P. J. Clapham, and J. A. Powell. 00. National Audubon Society Guide to Marine Mammals of the World. Goddard, P.D. and D.J. Rugh A group of right whales seen in the Bering seen in the Bering Sea in July Marine Mammal Science 1(): LeDuc, R. G., W. L. Perryman, J. W. Gilpatrick, Jr., J. Hyde, C. Stinchcomb, J. V. Carretta, and R. L. Brownell, Jr A note on recent surveys for right whales in the southeastern Bering Sea. J. Cetacean Res. Manage. (Special Issue) : Mellinger, D. K., K. M. Stafford, and C. G. Fox. 00. Seasonal occurrence of sperm whale (Physeter macrocephalus) sounds in the Gulf of Alaska, Mar. Mammal Sci. 0(1):8-6. Moore, S. E., J. M. Waite, L. L. Mazzuca, and R. C. Hobbs. 000c. Provisional estimates of mysticete whale abundance on the central Bering Sea shelf. J. Cetacean Res. Manag. (3):7-3. Moore, S. E., J. M. Waite, N. A. Friday, and T. Honkalehto. 00. Distribution and comparative estimates of cetacean abundance on the central and south-eastern Bering Sea shelf with observations on bathymetric and prey associations. Progr. Oceanogr. 55(1- Munger, L. M. and J. A. Hildebrand. 00. Final Report: Bering Sea Right Whales: Acoustic recordings and public outreach. NPRB Grant T-100. NatureServe NatureServe Explorer: An online encyclopedia of life. Version 5.0. NatureServe, Arlington, VA. Available National Oceanic and Atmospheric Administration (NOAA). 00. Press release, October 1, 00: Scientists double tally of known right whales. Available online at: Accessed 31Oct005. North Pacific Right Whale Recovery Team. 00. National recovery strategy for the North Pacific right whale (Eubalaena japonica) in Pacific Canadian waters. Fisheries and Oceans Canada (DFO), Vancouver, B.C. 8 pp. Rice, D. W Marine mammals of the world: systematics and distribution. Society for Marine Mammalogy, Special Publication Number. ix + 31 pp. Rosenbaum, H. C., R. L. Brownell, Jr., M. W. Brown, C. Schaeff, V. Portway, B. N. White, S. Malik, L. A. Pastene, N. J. Patenaude, C. S. Baker, M. Goto, P. B. Best, P. J. Clapham, P. Hamilton, M. Moore, R. Payne, V. Rowntree, C. T. Tynan, and R. DeSalle. Shelden, NOAA, personal communication Shelden, K. E., S. E. Moore, J. M. Waite, P. R. Wade, and D. J. Rugh Historic and current habitat use by North Pacific right whales Eubalaena japonica in the Bering Sea and Gulf of Alaska. Mammal Rev. 35: Sheldon, K. E. W. and P. J. Clapham (eds.) Habitat requirements and extinction risks of eastern North Pacific Right Whales. AFSC Processed Report NOAA, NMFS, Alaska Fisheries Science Center, NMML, Seattle, WA.

5 Tynan, C. T., D. P. DeMaster, and W. T. Peterson Endangered right whales on the southeastern Bering Sea shelf. Science 9: 189. Wade, P. R., A. Kennedy, R. LeDuc, J. Barlow, J. Carretta, K. Shelden, W. Perryman, R. Pitman, K. Robertson, B. Rone, J. C. Salinas, A. Zerbini, R. L. Brownell Jr., and P. J. Clapham The world's smallest whale population? Biol Lett. 7: Wade, P. R., A. De Robertis, K. R. Hough, R. Booth, A. Kennedy, R. G. LeDuc, L. Munger, J. Napp, K. E. W. Shelden, S. Rankin, O. Vasquez, and C. Wilson. 011b. Rare detections of north pacific right whales in the Gulf of Alaska, with observations of their Waite, J. M., K. Wynne, and D. K. Mellinger Documented sighting of a North Pacific right whale in the Gulf of Alaska and post-sighting acoustic monitoring. Northwest. Nat. 8:38-3. Wilson, D. E., and D. M. Reeder (eds) Mammal Species of the World: a Taxonomic and Geographic Reference. Second Edition. Smithsonian Institution Press, Washington, DC. Xviii pp. Available online at: Wynne, K Guide to the mammals of Alaska. Alaska Sea Grant College Program, University of Alaska Fairbanks, Fairbanks, AK. Version date: 1//013 Report authors: K. Walton, T. Gotthardt, and T. Fields Alaska Natural Heritage Program University of Alaska Anchorage Anchorage, AK For details on the development of the ASRS and criteria, please see: Gotthardt, T. A., K. M. Walton, and T. L. Fields. 01. Setting Conservation Priorities for Alaska's Wildlife Action Plan. Alaska Natural Heritage Program, University of Alaska Anchorage, AK. 5