World Wide Catalog 1995 Summer/World_Wide_Catalog_InfoMagic_Summer_1995.iso/pages/kssnmfsh.gov/tmcintyr/text/chapter7.txt

Text File | 1995-06-11 | 15KB | 243 lines

VII.  Stranding Networks and National Marine Mammal
Tissue Bank


      During 1990 and 1991, NMFS completed its review of the stranding network program,
implemented changes to respond to program weaknesses, established the marine mammal tissue
bank, and created a Task Force on Unusual Mortality.  This chapter describes these activities
and highlights of Regional programs.


Program Review

      During 1990, NMFS completed its review of stranding network capabilities and actions
required to improve data collection.  The review found inconsistencies in the Regional programs.
The review also identified basic data that should be collected at stranding events.  In response
to these findings, NMFS recommended the standardization of certain element and developed a
common set of program goals.  These goals are:

1. To achieve maximum feasible reporting of and response to stranding events;

2.    To achieve accurate documentation of data on stranding report forms;

3.    To provide for the protection, welfare, and humane treatment (including, when
      appropriate, euthanasia) of live stranded animals;

4.    To provide, when appropriate, for the rehabilitation of sick or injured marine mammals
      and the care of abandoned or orphaned immature animals.  Once rehabilitated, it will be
      a primary goal that such animals be returned to the wild.  As a secondary goal, such
      animals may serve as a substitute for capturing animals from the wild under public
      display permits;

5.    To gain the maximum amount of scientific information from dead stranded marine
      mammals and, where consistent with other goals, from live stranded marine mammals;

6. To generate information that will assist in making management decisions on both marine
   mammals and fisheries;

7. To the extent feasible, tissues from stranded marine mammals should be collected, curated
   in accordance with professional standards, and provided to legitimate researchers and to
   institutions that maintain marine mammal collections meeting curatorial and archival
   standards;

8. To collect and preserve tissues in accordance with standard protocols which can be used to
   monitor natural mortality and the types and levels of environmental contaminants; and

9. To disseminate accurate information from marine mammal strandings for scientific and
   public education purposes.

                                     Recent mortality events revealed a lack of baseline data and the need for high quality
tissue samples from freshly dead animals.  NMFS has responded to these deficiencies by
preparing a field guide that provides protocols for information collection and tissue sampling.
In addition, the Service has also prepared and pre-positioned tissue sampling kits throughout the
Southeast Region.  To facilitate research efforts associated with stranded animals, the Assistant
Administrator for Fisheries determined that a research permit was not required for tagging
stranded animals that have been rehabilitated and released.  Tagging or marking allows
researchers to identify animals that re-strand.  Radio tagging enables researchers to monitor the
movement of rehabilitated animals.


Tissue Bank

                                     Following the 1987-1988 mortality of bottlenose dolphins on the eastern U.S. coastline,
NMFS realized that researchers lacked adequate baseline data to investigate this event.  This
deficiency was particularly acute with respect to the impacts of anthropogenic contaminants.  In
response, NMFS initiated steps to establish a National Marine Mammal Tissue Bank.  A number
of activities have been undertake associated with the tissue bank, including a rulemaking
regarding the disposition of tissues, preliminary studies, and the development of quality (QA)
procedures.


Rulemaking

                                     On August 20, 1991, NMFS published a rule that clarified authority to retain or transfer
tissues from stranded marine mammals.  The rule allows salvage of tissues from stranded
animals by authorized individuals and requires that tissues be properly curated and registered
with the appropriate NMFS Regional office.  In addition, the regulation established procedures
for transfer of tissues.  Transfer of tissues to authorized individuals is allowed without prior
authorization.  Advance notice, however, is required when tissues are transferred to individuals
without permits.


Preliminary Studies

                                     NWFSC is conducting analyses to establish baseline concentrations of selected chemical
contaminants and biotoxins in marine mammals.  Specific contaminants of concern include
chlorinated hydrocarbons (e.g. PCBs), chlorinated pesticides, and heavy metals.  The studies
used tissues obtained from pilot whales stranded along the Atlantic Coast, bottlenose dolphins
stranded in the Gulf of Mexico, and gray whales stranded along the Pacific and Alaska coasts.
Results showed elevated levels of PCBs and several heavy metals in pilot whales.  Several
mother-fetus pairs were analyzed and results, to date, show maternal transfer of selected metals
(e.g., cadmium) to the fetus.  Concentrations of chlorinated hydrocarbons and some trace metals
in the bottlenose dolphin tissue samples prompted researchers to expand this effort in September
1991.  In contrast, concentrations of anthropogenic contaminants in gray whales were generally
less than the levels in pilot whales and bottlenose dolphins, and are considered to be below levels
of toxicological  concern.


Quality Assurance Procedures

                                     The National Institute of Standards and Technology (NIST) is developing a Quality
Assurance (QA) program to ensure accuracy, precision, level of detection, and
intercomparability of chemical analyses of tissue samples.  NIST is implementing this program
through (1) interlaboratory comparison exercises and the development of Standard Reference
Materials (SRMs).  Interlaboratory comparisons involve the preparation of tissue control
materials using tissues collected from stranded pilot whales.  NIST distributed the samples to
NWFSC and several other laboratories for trace element and organic contaminant analyses.  The
results from this exercise will soon be compiled and distributed.

                                     NIST has initiated development of a whale blubber SRM for use in measuring PCBs and
chlorinated pesticides in marine mammal tissue.  Tissue control material will be distributed to
NWFSC and other interested laboratories as a second comparison exercise.  Several different
approaches will be used to identify an approach that yields "certified" concentrations.  The whale
blubber SRM should be available by October 1992.  Development of a whale liver SRM for
trace element analysis is planned.


Task Group on Unusual Marine Mammal Mortalities

                                     NMFS is concerned about unusual marine mammal mortality events.  In response, the
Service has established a Task Group with representatives from several scientific specialties.
Members of the task group are consulted when an unusual mortality is suspected.  At a meeting
on April 10, 1991, the task group defined criteria for initiating consultations. These criteria are:

  A marked increase in the magnitude of strandings when compared with prior records.
   Magnitude by itself may not be an indication of an unusual mortality event and should be
   weighed against other knowledge;

  Animals are stranding at a time of the year when strandings are unusual;

  An increase in strandings is occurring in a very localized area (possibly suggesting a
   localized problem), is occurring throughout the geographic range of a species/population, or
   spreads geographically with time;

  The age or sex composition of the stranded animals is different than that of animals that
   normally strand in the area at a specific time of the year;

  Stranded animals exhibit a similar or unusual pathology or the general physical condition
   (e.g., blubber thickness) of stranded animals is different from what is normally seen; and

  Unusual or severely endangered species are stranding.  Stranding of three or four right
   whales, for example, may be cause for concern whereas stranding of a similar number of
   gray whales would not.

                                     Using these criteria, NMFS staff and researchers contacted the Task Group three times
in 1991.  In the first case, 38 (*what kind?) seals stranded in the Long Island area from mid-
February to mid-May.  The rate was above normal and many of the animals had a similar
pathology: small, dark, raised rhomboidal lesions on the skin.  Analyses of some samples
tentatively attributed the stranding to an Erysipelothrix bacillus which was cultured from some
of the seals.  These strandings occurred along the Long Island coast, and similar mortalities were
not observed in adjacent states.  "Ice" seals continue to strand as far south as New Jersey.

                                     The second incident involved a higher than normal stranding rate of California sea lions
along the central California coast from late July to the end of October 1991.   Nearly 150
animals were diagnosed as having leptospirosis, a disease that is endemic in the population.
Based on this finding, the task group's only recommendation was to monitor the number of
animals affected.

                                     From September to December 1991, 35 bottlenose dolphins stranded in the counties
surrounding Sarasota, FL, more than three times the historical rate.  The majority of the animals
were juvenile males.  Analyses are being conducted but results are not yet available.


Regional Stranding Networks

                                     The following descriptions of Regional stranding activity presents significant
accomplishments and summarizes stranding reports.  All strandings are reported in exhibit D-1
in Appendix D.

Northeast

                                     In 1990, the state of Maryland, with the assistance of the National Aquarium in
Baltimore, began to take a more active role in the Regional Network.  The state of Delaware's
involvement also increased.

                                     The Region reported the following stranding data and significant events.  In 1990, there
were 174 pinniped and 164 cetacean strandings.  Reported strandings increased in 1991 to 276
pinnipeds and 225 cetaceans.

                                     The cetacean totals include a number of mass stranded pilot whales.  In September 1990,
fifty-five pilot whales stranded in Hyannis, MA.  Two juveniles were rehabilitated at the New
England Aquarium and released in the spring of 1991.  Four separate stranding events involving
96 pilot whales were reported during the fall and winter of 1991.  Efforts to return the whales
to the wild resulted in only 37 successful releases.  Six of 23 whales tagged and released were
observed one month later swimming normally near a group of 30 untagged whales.

                                     A Cape Cod stranding response group began in December 1991 for the purpose of getting
to stranded pilot whales quickly, with experienced personnel, to effect a quick release of the
animals.


Southeast

                                     The Southeast Stranding Network is comprised of over 100 participants who are issued
Letters of Authorization (LOA) by the Region.  The Southeast Region maintains a directory of
participants which includes LOA holders and authorized government workers.  Following a
response to a stranding event, participants complete and submit a standard form.  A volunteer
compiles data from these forms and produces a quarterly report.

                                     A major initiative in the Region is a cooperative effort between the SEFSC's Miami
Laboratory and the Stranding Network to improve both the quantity and quality of data obtained
from stranding events.  As a result of this effort, SEFSC has developed a multidisciplinary
approach that encompasses seven themes.  Of these seven themes, four relate to population
biology and the remainder are associated with the extent and causes of mortality.

                                     In 1990, there were 728 documented strandings of cetaceans in the Southeast Region.
Bottlenose dolphins accounted for nearly 80 percent of the strandings, while the remainder
included at least 16 other species.  During 1991, there were 632 documented strandings of
cetaceans.  Once again, bottlenose dolphins accounted for the majority of strandings (nearly 70
percent),  and 21 additional species accounted for the remainder of the strandings.


Southwest

                                           The Region reported 1,233 pinniped strandings in 1990 and 167 in 1991.
Reported cetacean strandings decreased from 88 in 1990 to 67 in 1991.


Northwest

                                     In 1990, the Northwest Marine Mammal Stranding Network responded to 227 reported
strandings or unusual events in Oregon and Washington.  Pinniped strandings accounted for
the
majority (85 percent) of these investigations.  Network participants investigated 136 reported
standings or unusual events in 1991; 77 percent of these involved pinnipeds.  Unusual events
include reports of live animals in distress.


Alaska

                                     The Alaska Region Stranding Network investigated 87 cetacean strandings in 1990.  Of
these, the most common species were gray whales (27 strandings), harbor porpoise (17), and
killer whale (10).  In 1991, the network reported 39 cetacean strandings.  The most common
species again were gray whales (17), harbor porpoise (9), and killer whale (8).

                                     With a few notable exceptions, most stranding reports involve dead animals.  In 1990,
a humpback whale live-stranded on a sand bar in the Copper River Delta.  The whale managed
to back off with its flippers and was gone at high tide.  Six killer whales live-stranded
temporarily in Chignik lagoon in 1990.  One of the animals re-stranded a day later and died, and
four days later, a second whale was found dead within the area.  A pathological investigation
was unable to identify a cause of this stranding event.  During 1991, six killer whales live
stranded in Turnagain Arm.  NMFS biologists applied wet blankets to some of the animals until
high tide occurred, freeing the animals with no observable significant damage.