2010-19143. Draft 2010 Marine Mammal Stock Assessment Reports

AGENCY:

National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce.

ACTION:

Notice; request for comments.

SUMMARY:

NMFS reviewed the Alaska, Atlantic, and Pacific regional marine mammal stock assessment reports (SARs) in accordance with the Marine Mammal Protection Act. SARs for marine mammals in the Alaska, Atlantic, and Pacific regions were revised according to new information. NMFS solicits public comments on draft 2010 SARs.

DATES:

Comments must be received by November 2, 2010.

ADDRESSES:

The 2010 draft SARs, summaries of them, and references cited in this notice are available in electronic form via the Internet at http://www.nmfs.noaa.gov/​pr/​sars/​.

Copies of the Alaska Regional SARs may be requested from Robyn Angliss, Alaska Fisheries Science Center, NMFS, 7600 Sand Point Way, NE BIN 15700, Seattle, WA 98115-0070.

Copies of the Atlantic and Gulf of Mexico Regional SARs may be requested from Gordon Waring, Northeast Fisheries Science Center, 166 Water St., Woods Hole, MA 02543.

Copies of the Pacific Regional SARs may be requested from Jim Carretta, Southwest Fisheries Science Center, 8604 La Jolla Shores Drive, La Jolla, CA 92037-1508.

Send comments or requests for copies of reports to: Chief, Marine Mammal and Sea Turtle Conservation Division, Office of Protected Resources, National Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-3226, Attn: Stock Assessments. Comments may also be sent via facsimile (fax) to 301-427-2522 or via email to [e-mail].

FOR FURTHER INFORMATION CONTACT:

Tom Eagle, Office of Protected Resources, 301-713-2322, ext. 105, e-mail [e-mail]; Robyn Angliss 206- 526-4032, e-mail [e-mail], regarding Alaska regional stock assessments; Gordon Waring, 508-495-2311, e-mail [e-mail], regarding Atlantic regional stock assessments; or Jim Carretta, 858-546-7171, e-mail [e-mail], regarding Pacific regional stock assessments.

SUPPLEMENTARY INFORMATION:

Background

Section 117 of the Marine Mammal Protection Act (MMPA) (16 U.S.C. 1361 et seq.) requires NMFS and the U.S. Fish and Wildlife Service (FWS) to prepare stock assessments for each stock of marine mammals occurring in waters under the jurisdiction of the United States. These reports must contain information regarding the distribution and abundance of the stock, population growth rates and trends, estimates of annual human-caused mortality and serious injury from all sources, descriptions of the fisheries with which the stock interacts, and the status of the stock. Initial reports were completed in 1995.

The MMPA requires NMFS and FWS to review the SARs at least annually for strategic stocks and stocks for which significant new information is available, and at least once every 3 years for non-strategic stocks. NMFS and the FWS are required to revise a SAR if the status of the stock has changed or can be more accurately determined. NMFS, in conjunction with the Alaska, Atlantic, and Pacific Scientific Review Groups (SRGs), reviewed the status of marine mammal stocks as required and revised reports in the Alaska, Atlantic, and Pacific regions to incorporate new information. NMFS solicits public comments on the draft 2010 SARs.

Alaska Reports

In the Alaska region, SARs for 23 stocks (14 strategic and 9 non-strategic) were updated; 13 SARs were not updated. Most revisions included updates of abundance and/or mortality estimates. None of the updates resulted in change of status of a stock. Estimates of mortality and serious injury incidental to observed Federally-managed fisheries remain based on information obtained during the period, 2002-2006. Preliminary results from 2007 and 2008 are discussed in the section related to fishery mortality; however, these preliminary estimates have not yet been fully reviewed and are not combined with the previous estimates to obtain a new 5-year average.

After receiving increasing reports of sightings of narwhal in waters under U.S. jurisdiction, a new SAR for narwhal has been added in the Alaska region. Narwhals observed in Alaskan waters likely belong to populations outside U.S. waters, and the stock of origin is unknown. Therefore, the SAR is for an unidentified stock of narwhal.

As recommended by the Alaska SRG, the draft 2010 SAR for Cook Inlet beluga whales alters the way that abundance and the minimum estimate of abundance (Nmin) are reported. The abundance reported in the 2010 draft SAR is the mean of estimates from 2007 (375), 2008 (375), and 2009 (321) and is 375. Nmin, which is a function of the abundance estimate and the coefficient of variation (CV) of that estimate, is 326. Nmin is used within the SAR only for calculating PBR, which remains undetermined for this stock.

A new abundance estimate for the 2006/2007 survey is reported in the eastern North Pacific gray whale SAR. After realizing that early estimates of abundance of this stock were calculated from models using different parameters, NMFS scientists re-analyzed the entire history of abundance estimates for this stock using consistent methods (Laake et al. 2009). Punt and Wade (2009) used the new abundance estimates to evaluate the status and trend of the stock. These new analyses are included in the SAR and reaffirm that the stock remains within its Optimum Sustainable Population limits.

NMFS scientists also considered guidance included in Taylor et al. (2003) to evaluate the potential to adjust recovery factors for stocks of endangered marine mammals in Alaska. This evaluation noted that for the central North Pacific (CNP) stock of humpback whales, Nmin exceeded 5,000 and the trend was increasing. For endangered stocks with such abundance and trend that have a CV of 0.5 or less, Taylor et al. (2003) suggest a recovery factor of 0.5; however, the CV reported in the CNP humpback whale SAR (0.3) is an assumed value. Accordingly, the recovery factor was increased from 0.1 to 0.3, which is the value recommended for those cases when CV of the abundance estimate is larger than 0.5. As has been reported in previous CNP humpback SARs, the PBR is reported for the entire stock as well as for feeding aggregations in AK, two of which retain 0.1 as the recovery factor in the PBR calculation.

Atlantic Reports

The draft 2010 SARs for 17 Atlantic Stocks were updated (9 strategic and 8 non-strategic) and 4 Gulf of Mexico stocks (2 strategic and 2 non-strategic). The updates included revised abundance and/or mortality estimates for these stocks, and one update resulted in a modified status of a stock (long-fined pilot whale).

In a SAR prepared in 2008 seven stocks of Atlantic coastal bottlenose dolphins were grouped into a single report. For the draft 2010 SARs, each stock of coastal bottlenose dolphins is presented in a separate report. Stock structure was revised due to additional information into five stocks of coastal bottlenose dolphins in the Atlantic Ocean: Northern Migratory stock, Southern Migratory stock, South Carolina/Georgia Coastal stock, Northern Florida Coastal stock, and Central Florida Coastal stock. All of these stocks are strategic due to their origins of the previously identified, depleted coastal migratory stock.

Three stocks of coastal bottlenose dolphins had been included in a single SAR for Northern Gulf of Mexico Coastal stocks in 2007-2009. These stocks are each described in a separate report in 2010, and are identified as the Gulf of Mexico Eastern Coastal stock, Gulf of Mexico Northern Coastal stock, and Gulf of Mexico Western Coastal stock. From 2007-2009, each of these stocks was considered a strategic stock because the abundance estimate was outdated, PBR was undetermined, and human-caused mortality was occurring. Aerial surveys conducted in 2007 provided abundance estimates for the Eastern and Northern Coastal stocks, which in turn led to the status becoming non-strategic. The Western Coastal stock was not surveyed in 2007. PBR remains undetermined, and status remains strategic.

Among the Gulf of Mexico, Bay, Sound, and Estuary stocks of bottlenose dolphins, two previously separated stocks were combined into a single stock (Sarasota Bay/Little Sarasota Bay). Accordingly, this SAR describes the status of 32, rather than 33, stocks of bottlenose dolphins. The abundance estimate of one of these stocks (Barataria Bay) became outdated, and that stock's PBR was changed to undetermined.

Analysis of the geographical separation in summer of long and short-finned pilot whale stocks in the Atlantic has been completed, and preliminary abundance estimates for the two stocks are included in the revised pilot whale reports. Similar analyses have not been completed for mortality and serious injury estimates; therefore, each of these SARs reports the combined mortality and serious injury estimate. The short-finned pilot whale stock remains non-strategic, but the status of the long-finned pilot whale stock is now considered strategic.

A new SAR is included for a Puerto Rico and Virgin Islands stock of sperm whales in the Caribbean Sea. The abundance estimate for the Western North Atlantic stock of harbor seals became outdated in 2010, and PBR for the stock was changed to undetermined. The harbor seal stock remains non-strategic.

Pacific Reports

In the Pacific region, SARs were revised for 51 stocks, and 12 SARs were added for a total of 63 draft 2010 SARs, including 12 “strategic” stocks, 48 “non-strategic” stocks, and three stocks of unknown status. The remaining 12 Pacific region stocks were not revised. General updates are as follows. Abundance estimates were updated for 41 stocks, and these updates did not change the status of most stocks. The new abundance for short-finned pilot whales increased the PBR so that the status of this stock was changed from strategic to non-strategic. Information updates for longline fisheries in the Pacific Islands region are also included in a fishery description appendix. Where available, information on subspecies designations has been included in these reports to reflect local taxonomic and conservation issues (Perrin et al. 2009).

The former Hawaii stock of spinner dolphin was renamed as the Hawaii pelagic stock, and five new near-shore stocks of spinner dolphins were identified in the Hawaiian Exclusive Economic Zone (EEZ). These new spinner dolphin stocks are the Hawaii (Island) stock, Oahu, Four Islands (Maui, Molokai, Lanai, and Kahoolawe) stock, Niihau stock, Kure-Midway stock, and the Pearl and Hermes stock.

The SAR for the Hawaii stock of bottlenose dolphin was renamed the Hawaii pelagic stock, and four new near-shore stocks were identified. The new bottlenose dolphin stocks are the Kauai-Niihau stock, Oahu stock, Four Islands stock, and the Hawaii (Island) stock.

Three new reports are added for dolphin stocks incidentally taken in longline fisheries or identified during nearshore surveys around American Samoa. American Samoa stocks are added for spinner dolphins, false killer whales, and rough-tooth dolphins. Estimates of mortality and serious injury are provided for false killer whales and rough-toothed dolphins, but there are no abundance estimates for the new American Samoa stocks. Accordingly, the status of each of the three new American Samoa stocks is unknown.

There is a substantial revision of the SAR for the Pacific Islands Stock Complex of false killer whales. Key revisions include stock identity and range, a newly recognized fishery, proration of incidental mortality and serious injury among stocks and fisheries, and abundance estimates for animals south of the U.S. EEZ around Hawaii. Revisions related to stock identity and geographic range include evidence that there is overlap in the ranges of the HI insular and pelagic stocks, both of which are exposed to commercial fishing operations of the Hawaii-based longline fisheries. The identity of the pelagic stock was revised to clarify that the stock occupies international waters as well as the U.S. EEZ around Hawaii; however, the geographic limits of the stock's range are unknown. The SAR also describes a new commercial fishery, the HI shortline fishery, for which there are anecdotal reports of interactions with false killer whales. Mortality and serious injury of false killer whales incidental to longline fishing are allocated among false killer whale stocks and fisheries by a statistical algorithm, as recommended by the Pacific SRG. The revised SAR also includes an abundance estimate (and PBR) calculated from a 2005 survey south of the HI EEZ, including international waters and the U.S. EEZ surrounding Johnston Atoll.

Dated: July 29, 2010.

James H. Lecky,

Director, Office of Protected Resources, National Marine Fisheries Service.