NOAA Technical Memorandum NMFS NE 116
U.S. Atlantic
Marine Mammal
Stock Assessments -- 1998
by Gordon T. Waring1,
Debra L. Palka1, Phillip J. Clapham1,
Steven Swartz2, Marjorie C. Rossman1, Timothy V.N. Cole1,
Kathryn D. Bisack1, and Larry J. Hansen3
1National
Marine Fisheries Service, 166 Water St., Woods Hole, MA 02543-1026
2National Marine Fisheries Service, 75 Virginia Beach
Dr.,Miami, FL 33149-1003
3National Marine Fisheries Service, 219 Ft. Johnson Rd.,
Charleston, SC 29412
Print
publication date February 1999;
web version posted September 30, 2002
Citation: Waring GT, Palka DL, Clapham PJ, Swartz S, Rossman MC, Cole TVN, Bisack KD, Hansen LJ. 1999. U.S. Atlantic
Marine Mammal Stock Assessments -- 1998. US Dep Commer, NOAA Tech Memo NMFS NE 116; 184 p.
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ACKNOWLEDGMENTS
The authors wish to thank and acknowledge Janeen Quintal for her technical
assistance throughout the preparation of this report. The authors also
wish
to acknowledge contributions by the Northeast Fisheries Science Center (NEFSC)
Sea Sampling Investigation, Dana Hartley and Kim Thounhurst (Northeast
Regional
Office), and Blair Mase, Keith Mullin, and Jim Tobias (Southeast Fisheries
Science Center). Also, we acknowledge advice and comments provided by
NEFSC: Richard
Merrick and Fred Serchuk; and the Atlantic Scientific Review Group: Donald
Baltz, Solange Brault, Joseph DeAlteris, James Gilbert, Mike Harris,
Robert Kenney,
Robert MacKinnon, James Mead, Daniel Odell, Andrew Read, Randall Wells, and
Graham Worthy. We also thank Paul Wade, NMFS, Office of Protected Species,
for
his comments and guidance at the SRG review meeting, the Marine Mammal Commission,
the Humane Society of the United States, the Blue Water Fishermen’s
Association and Hal Caswell (Woods Hole Oceanographic Institution) for
their constructive comments and advice.
EXECUTIVE
SUMMARY
Under the 1994 amendments of the Marine Mammal Protection Act (MMPA),
the National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife
Service (USFWS) were required to generate stock assessment reports (SAR)
for all marine mammal stocks in waters within the U.S. Exclusive Economic
Zone (EEZ). The first reports for the Atlantic (includes the Gulf of
Mexico) were published in July 1995 (Blaylock et al. 1995). The MMPA
requires NMFS and USFWS to review these reports annually for strategic
stocks of marine mammals and at least every 3 years for stocks determined
to be non-strategic. The second edition of the SARs (1996 assessments)
was published in October 1997 and contained all the previous reports,
but major revisions and updating were only completed for strategic stocks
(Waring et al. 1997). Updated reports were identified by a 1997 date-stamp
at the top right corner at the beginning of each report. The current
report contains only assessment reports for the Atlantic stocks, and
updated reports are identified by a December 1998 date-stamp. This format
was selected to facilitate availability and because the draft 1999 SARs
are expected to be available in February 1999.
This report was prepared by staff of the Northeast Fisheries Science
Center (NEFSC), and Southeast Fisheries Science Center (SEFSC). NMFS
staff presented the reports at the May 1998 meeting of the Atlantic Scientific
Review Group (ASRG), and subsequent revisions were based on their contributions
and constructive criticism. In July 1998, the revised report was available
for a 90-day public comment period. The current version reflects changes
made in response to the public comments.
Table 1 contains a summary, by species, of
the information included in the stock assessments, and also indicates
those that have been revised since the 1997 publication. A total of 27
of the 31 Atlantic stock assessment reports were revised for 1998. Most
proposed changes incorporate new information into abundance or mortality
estimates. The revised SARs include 15 of the strategic stocks and 12
of the non-strategic stocks relative to the 1996 assessments. Some of
the revisions clarified fisheries mortality information which resulted
in changes to the status of some stocks. Information on human interactions
(fishery and ship strikes) between the North Atlantic right whale and
North Atlantic humpback whale stocks were re-reviewed and updated. The
1993 fishery induced mortality of a North Atlantic right whale has been
reassigned from the pelagic driftnet fishery to the lobster fishery based
on a reexamination of all information. Abundance estimates for humpback
whales, Canadian east coast stock of Minke whales, Western North Atlantic
stocks of common dolphins, and harbor seals have been revised. The Western
North Atlantic stock of Atlantic white-sided dolphins is now considered “strategic” based
on incidental mortality in the New England sink gillnet and North Atlantic
bottom trawl fisheries. The Western North Atlantic stock of long-finned
pilot whales will remain “strategic” based on mortality in
the Atlantic squid, mackerel, butterfish trawl fishery. The Western North
Atlantic stock of pygmy sperm whale is no longer considered “strategic”.
One strategic stock that was not updated, but extensively reviewed by
the ASRG was the Western North Atlantic stock (stock complex) of coastal
bottlenose dolphins. New information on observed mortality in the 1995-1996
mid-Atlantic coastal gillnet fishery was presented. One mortality was observed
in 1996, and the preliminary mortality estimate was 4.1 (CV = 0.88). Fishery
effort data are under review and 1996-1997 mortality estimates will be provided
in the draft 1999 assessment report.
This is a working document and individual stock assessment reports will
be updated as new information becomes available and as changes to marine
mammal stocks and fisheries occur. The authors solicit any new information
or comments which would improve future stock assessment reports.
INTRODUCTION
Section
117 of the 1994 amendments to the Marine Mammal Protection Act (MMPA)
requires that an annual stock assessment report (SAR) for each stock
of marine mammals that occurs in waters under U.S. jurisdiction, be prepared
by the National Marine Fisheries Service (NMFS) and the U.S. Fish and
Wildlife Service (FWS), in consultation with regional Scientific Review
Groups (SRG). The SRGs are a broad representation of marine mammal and
fishery scientists and members of the commercial fishing industry mandated
to review the marine mammal stock assessments and provide advice to the
Assistant Administrator for NMFS. The reports are then made available
on the Federal Register for public review and comment before final publication.
The MMPA requires that each SAR contain several items, including: (1)
a description of the stock, including its geographic range; (2) a minimum
population estimate, a maximum net productivity rate, and a description
of current population trend, including a description of the information
upon which these are based; (3) an estimate of the annual human-caused
mortality and serious injury of the stock, and, for a strategic stock,
other factors that may be causing a decline or impeding recovery of the
stock, including effects on marine mammal habitat and prey; (4) a description
of the commercial fisheries that interact with the stock, including the
estimated number of vessels actively participating in the fishery and
the level of incidental mortality and serious injury of the stock by
each fishery on an annual basis; (5) a statement categorizing the stock
as strategic or not, and why; and (6) an estimate of the potential biological
removal (PBR) level for the stock, describing the information used to
calculate it. The MMPA also requires that SARs be updated annually for
stocks which are specified as strategic stocks, or for which significant
new information is available, and once every three years for nonstrategic
stocks.
Following enactment of the 1994 amendments, the NMFS and FWS held a
series of workshops to develop guidelines for preparing the SARs. The
first set of stock assessments for the Atlantic Coast (including the
Gulf of Mexico) were published in July 1995 in the NOAA Technical Memorandum
series (Blaylock et al. 1995). In April 1996, the NMFS held a workshop
to review proposed additions and revisions to the guidelines for preparing
SARs (Wade and Angliss 1997). Guidelines developed at the workshop were
followed in preparing the 1996 (Waring et al. 1997) and 1998 SARs. A
1997 SAR was not produced.
In this document, major revisions and updating of the SARs were only
completed for Atlantic Coast strategic stocks and stocks for which significant
new information were available. These are identified by the 1998 date-stamp
at the top right corner at the beginning of each report. Gulf of Mexico
SARs were not updated from Waring (et al. 1997), therefore were not included
in this document. Except for some minor editorial changes, stocks designated
by the 1995 or 1997 date-stamp are unchanged from the 1997 document (Waring
et al. 1997).
In this document, the status of long-finned pilot whale was changed
to non-strategic because the 5-year (1992-1996) mean annual mortality
in fishing operations was below PBR.
REFERENCES
CITED
Blaylock, R. A., J. W. Hain, L.
J. Hansen, D. L. Palka, and G. T. Waring. 1995. U.S. Atlantic
and Gulf of Mexico marine mammal stock assessments. NOAA Tech.
Memo. NMFS-SEFSC-363, 211 pp.
Wade, P. R. and R. P. Angliss. 1997. Guidelines for assessing
marine mammal stocks: Report of the GAMMS workshop April 3-5,
1996, Seattle, Washington. NOAA Tech. Memo. NMFS-OPR-12, 93 pp.
Waring, G. T., D. L. Palka, K. D. Mullin, J. H. W. Hain, L.
J. Hansen, and K. D. Bisack. 1997. U.S. Atlantic and Gulf of
Mexico marine mammal stock assessments. NOAA Tech. Memo. NMFS-NE-114,
250 pp.
