Protected Species: Marine Mammals' Predation of Varieties of Fish (Letter
Report, 09/10/93, GAO/RCED-93-204).

According to government officials, the hunting of steelhead salmon by
California sea lions at Ballard Locks in Seattle, Washington, is the
only documented case in which predation by one species is threatening
the existence of another, although federal officials suspect that the
adverse predation of fish by protected seals may also be occurring at
the Columbia River and in the state of Maine. Efforts to counteract the
predation at Ballard Lock, including relocating the sea lions and
driving them away from the locks, have been unsuccessful.  Other
possible options include capturing and holding the sea lions during the
steelhead's migration and making structural changes to the locks and the
accompanying spillway.  The National Marine Fisheries Service has
considered but rejected the possibility of controlling the sea lion
population through lethal means.

--------------------------- Indexing Terms -----------------------------

 REPORTNUM:  RCED-93-204
     TITLE:  Protected Species: Marine Mammals' Predation of Varieties 
             of Fish
      DATE:  09/10/93
   SUBJECT:  Endangered species
             Wildlife conservation
             Seals (mammals)
             Wildlife management
             Environmental legislation
             Environmental policies
             Anadromous fishes
             Fishes
             Marine policies
IDENTIFIER:  Ballard Locks (WA)
             Columbia River (WA)
             Maine
             Puget Sound (WA)
             Snake River (ID)
             Columbia River Basin (WA)
             Lower Granite Dam (WA)
             Narraguagus River (ME)
             Dennys River (ME)
             Machias River (ME)
             East Machias River (ME)
             Pleasant River (ME)
             
**************************************************************************
* This file contains an ASCII representation of the text of a GAO        *
* report.  Delineations within the text indicating chapter titles,       *
* headings, and bullets are preserved.  Major divisions and subdivisions *
* of the text, such as Chapters, Sections, and Appendixes, are           *
* identified by double and single lines.  The numbers on the right end   *
* of these lines indicate the position of each of the subsections in the *
* document outline.  These numbers do NOT correspond with the page       *
* numbers of the printed product.                                        *
*                                                                        *
* No attempt has been made to display graphic images, although figure    *
* captions are reproduced. Tables are included, but may not resemble     *
* those in the printed version.                                          *
*                                                                        *
* A printed copy of this report may be obtained from the GAO Document    *
* Distribution Facility by calling (202) 512-6000, by faxing your        *
* request to (301) 258-4066, or by writing to P.O. Box 6015,             *
* Gaithersburg, MD 20884-6015. We are unable to accept electronic orders *
* for printed documents at this time.                                    *
**************************************************************************


Cover
================================================================ COVER


Report to the Honorable
Slade Gorton, U.S.  Senate

September 1993

PROTECTED SPECIES - MARINE
MAMMALS' PREDATION OF VARIETIES OF
FISH

GAO/RCED-93-204

Protected Species


Abbreviations
=============================================================== ABBREV

  ESA - Endangered Species Act
  FWS - Fish and Wildlife Service
  MMPA - Marine Mammal Protection Act
  NMFS - National Marine Fisheries Service

Letter
=============================================================== LETTER


B-254186

September 14, 1993

The Honorable Slade Gorton
United States Senate

Dear Senator Gorton: 

As you know, the Congress is considering the reauthorization of two
major species protection laws--the Marine Mammal Protection Act
(MMPA)\1 and the Endangered Species Act (ESA).\2 In this context, you
raised concern about the predation of steelhead\3 by California sea
lions, protected under the MMPA, which is occurring at the Ballard
Locks\4 in Seattle, Washington.  You asked us to examine the impacts
of species protected by the MMPA and ESA on species not protected by
these laws. 

In response to your request and as agreed with your office, we
obtained information on (1) instances in which predation by an MMPA-
or ESA-protected species was threatening the existence of another
species and (2) any efforts being undertaken to address such adverse
predation.  You also asked for our comments on the use of federal
agencies' authorities under these laws to resolve adverse predation
by protected species.  The Department of Commerce's National Marine
Fisheries Service (NMFS) and the Department of the Interior's U.S. 
Fish and Wildlife Service (FWS) have primary responsibility for
administering the MMPA and ESA.  This letter provides the results of
our work. 


--------------------
\1 16 U.S.C.  1361 et seq. 

\2 16 U.S.C.  1531 et seq. 

\3 Steelhead are a species of anadromous fish in the salmon family. 

\4 These locks are officially named the Hiram M.  Chittenden Locks. 


   RESULTS IN BRIEF
------------------------------------------------------------ Letter :1

According to NMFS and FWS officials, the predation occurring at the
Ballard Locks by California sea lions is the only documented instance
in which predation by a protected species is threatening the
existence of another species.  However, at two other locations--the
Columbia River and the state of Maine--federal officials believe that
the adverse predation of fish by protected sea lions or seals may
also be occurring, although the extent of predation has not been
confirmed. 

Efforts to mitigate predation have been taken at the Ballard Locks. 
The efforts, undertaken by federal and state agencies, have included
relocating the sea lions and employing means to drive them away from
the locks; but the efforts have been unsuccessful.  Other possible
options that have been identified include temporarily capturing and
holding the sea lions during the migration of steelhead and making
structural changes to the locks and accompanying spillway.  Finally,
NMFS has considered taking stronger action (lethal removal) to
control the sea lion population, but concluded that the MMPA's
provisions do not authorize the use of lethal measures at this time
to resolve the Ballard Locks predation situation. 

The potential adverse predation in the Columbia River involves the
predation of ESA-protected salmon by MMPA-protected sea lions and
harbor seals.  Should this predation be confirmed as posing a threat
to the salmon, it is not clear how the authorities contained in these
two laws would be used to resolve the predation. 


   BACKGROUND
------------------------------------------------------------ Letter :2

The MMPA was enacted in 1972, at a time when the populations of
certain marine mammal species were in serious decline.  With few
exceptions, the MMPA placed a moratorium on "taking" (harassing,
hunting, capturing, or killing) marine mammals.  The act was most
recently reauthorized in 1988, and its current authorization expires
this year. 

The MMPA's stated goal is to restore and maintain marine mammal
species and population stocks to their "optimum sustainable
population." The MMPA defines optimum sustainable population as the
number of animals within any population stock that will result in the
maximum productivity of the population or the species, taking into
account the carrying capacity of the habitat and the health of the
ecosystem in which the species lives. 

Since the MMPA's enactment, some marine mammal populations have
grown, while others have not.  For example, a 1992 NMFS report noted
that the estimated West coast population of 180,000 California sea
lions may be higher than any known historical level.\5 However, other
marine mammals, such as the West Indian manatee, Hawaiian monk seal,
and some species of whales, are still at perilous levels and have
been listed as endangered or threatened species under the ESA.\6

Passed in 1973, the ESA's goal is to restore species so that they can
live in self-sustaining populations without the act's protection. 
Unlike the MMPA, the ESA does not call for achieving optimum
sustainable populations of protected species but, instead, aims at
preventing the extinction of protected species.  The ESA provides for
the development of recovery plans for all species determined to be
endangered or threatened, unless such plans would not benefit the
species.  The goal of such plans is to restore species so they can
live as viable self-sustaining components of their ecosystems.  When
this goal is met, the species can be removed from the ESA's
protection, referred to as delisting.\7

NMFS and FWS share administrative responsibility for the two acts. 
For the MMPA, NMFS is responsible for species of whales, dolphins,
porpoises, seals, and sea lions.  FWS is responsible for the walrus,
sea and marine otters, polar bear, manatee, and dugong.\8 For the
ESA, FWS is responsible for protecting freshwater and land species,
and NMFS is responsible for protecting most marine and anadromous
species. 


--------------------
\5 Prior to the MMPA's enactment, California sea lions were killed
for their oil, pelts, hides, and other products until the late 1930s
and were subject to bounty hunting in Oregon and Washington State
until the early 1960s. 

\6 An endangered species is any species at risk of extinction in all
or a significant portion of its range, whereas a threatened species
is one that is likely to become endangered in the foreseeable future
in all or a significant portion of its range. 

\7 If a marine mammal that had been listed under the ESA were
delisted, it would continue to be protected under the MMPA, as the
MMPA does not contain any listing or delisting provisions. 

\8 A dugong is an aquatic mammal related to the manatee. 


   FEW INSTANCES OF ACTUAL OR
   POTENTIAL ADVERSE PREDATION BY
   MARINE MAMMALS
------------------------------------------------------------ Letter :3

NMFS and FWS officials have identified instances at three locations
of actual or potential predation of another species by a protected
species.  Each of these instances involves seals or sea lions,
protected under the MMPA, preying on species of fish.\9 The three
instances vary greatly in the degree to which predation has been
documented. 


--------------------
\9 According to FWS officials, predation by an ESA-protected species
is less likely because populations of ESA-protected species are
generally too small to have a significant predatory impact on other
species. 


      PREDATION OF STEELHEAD RUNS
      BY SEA LIONS AT SEATTLE'S
      BALLARD LOCKS
---------------------------------------------------------- Letter :3.1

Completed in 1916, the Ballard Locks provide passage between Puget
Sound and two freshwater lakes (Lake Union and Lake Washington).  An
adjacent fish passage facility allows migrating fish, including
steelhead, to return from the ocean to freshwater spawning grounds. 
While male California sea lions wintering in the Puget Sound area had
been observed feeding on returning steelhead at the locks as early as
the 1970s, a predation problem did not come to public attention until
the 1980s, when one or two sea lions feeding on steelhead were
periodically observed. 

In 1985, Washington state officials noted serious declines in
steelhead runs at the Ballard Locks, and counts of steelhead passing
through the locks' fish passage facility showed that by 1991, the
Washington State Department of Wildlife's goal of having 1,600 wild
steelhead\10 returning to the spawning grounds had not been attained
for 6 of the previous 7 years.  By 1992, NMFS concluded that as many
as 30 to 60 sea lions were consuming almost 60 percent of the winter
run of wild steelhead and that one to three sea lions were
responsible for most of this predation.  In July 1993, the Washington
Department of Wildlife told us that the number of steelhead
successfully returning through the Ballard Locks to their spawning
grounds had fallen to fewer than 200. 


--------------------
\10 Wild runs of fish are genetically unique populations that have
maintained reproduction successfully without supplementation from
hatcheries. 


      PREDATION OF SALMON RUNS BY
      SEA LIONS AND HARBOR SEALS
      IN THE COLUMBIA RIVER
---------------------------------------------------------- Letter :3.2

Declining populations of certain wild salmon species in the Columbia
River and its major tributary, the Snake River, led NMFS to list the
Snake River sockeye salmon as an endangered species in November 1991
and certain runs of Snake River chinook salmon, including the spring
runs, as a threatened species in May 1992.  Also, increasing
populations of seals and sea lions, protected under MMPA, have been
inhabiting areas within the Columbia River Basin, and California sea
lions have been sighted in upriver areas--an occurrence for which
there is no historical documentation. 

Although dams on the Columbia and Snake Rivers are considered to be
the primary factors in the decline of the currently protected salmon
runs, other factors, including predation by sea mammals, are also
believed to have contributed to the decline.  According to a 1990
NMFS report,\11 an estimated 40 to 50 percent of the returning adult
spring chinook salmon at Lower Granite Dam on the Snake River had
teeth marks caused by marine mammal attacks, believed by NMFS to be
teeth marks left by harbor seals or California sea lions.  Where the
attacks took place or how many fish may have been killed prior to
their arrival at Lower Granite Dam was not known. 

NMFS is currently in the process of developing recovery plans for the
threatened and endangered Snake River salmon species.  As part of
this process, NMFS has attempted to determine the seriousness of
predation of salmon by analyzing existing information from a variety
of sources, including observations made at fish passage facilities
through Columbia and Snake River dams and hatcheries, and during
commercial and sport fishing activity.  In May 1993, a draft NMFS
report based on this analysis concluded that a potentially serious
predation problem caused by marine mammals may be occurring, but the
degree to which such predation has contributed to the decline of the
salmon runs could not yet be determined.  NMFS has called for further
studies to better assess the effect of predation. 


--------------------
\11 J.  Harmon and G.  Matthews, Evidence of Increase in Marine
Mammal Damage to Adult Spring Chinook Salmon in Columbia River,
Northwest and Alaska Fisheries Centers Quarterly Report,
April-May-June 1990. 


      PREDATION OF SALMON RUNS BY
      HARBOR SEALS IN SEVERAL
      MAINE RIVERS
---------------------------------------------------------- Letter :3.3

NMFS and state of Maine officials have identified the possibility of
a predation problem caused by protected species in five Maine
rivers--the Narraguagus, Dennys, Machias, East Machias, and Pleasant. 
Runs of wild North Atlantic salmon in these rivers have declined in
the past decade to levels that FWS and the Atlantic Sea Run Salmon
Commission, a state agency, consider dangerously low.\12

While the primary reason for the decline has been identified as the
salmon's low rate of survival while in the ocean, the commission
believes that predation by harbor seals may also be a factor on the
basis of reports from fishermen and local residents, who have
observed increased predation of Atlantic salmon by harbor seals in
recent years. 

Research on the extent of the predation of Atlantic salmon by harbor
seals has not yet been conducted.  In 1987, FWS and the state of
Maine asked NMFS to conduct such research; but NMFS declined, citing
a lack of funds.  Again, in October 1992, FWS and the commission
called for NMFS research to identify and monitor the reasons for the
declining Atlantic salmon populations.  According to FWS and NMFS
officials, neither agency has plans to conduct this research, because
limited funds are being used for other research in these rivers. 


--------------------
\12 Runs in two additional rivers--the Sheepcot and Duck Trap--may
also be at low levels, according to state officials. 


   UNSUCCESSFUL EFFORTS TO RESOLVE
   ADVERSE PREDATION
------------------------------------------------------------ Letter :4

Of the three instances in which predation is or may be a problem,
only at the Ballard Locks have actions been attempted to control
predation by sea lions.  The actions have been taken by federal and
state agencies and have included a variety of nonlethal harassment
techniques to keep the sea lions from the lock area.  The actions,
however, have been ineffective.  Other possible options include
capturing and holding the sea lions while the steelhead are present
or making structural changes to the locks and accompanying spillway. 
NMFS has also considered lethal alternatives, but while the MMPA
contains authority for the lethal removal of marine mammals in
certain circumstances, NMFS has concluded that this authority does
not apply to the current situation at the Ballard Locks. 


      INEFFECTIVE ACTIONS TAKEN AT
      BALLARD LOCKS
---------------------------------------------------------- Letter :4.1

Since 1985, NMFS has cooperated with the Washington Department of
Wildlife, the U.S.  Army Corps of Engineers (which operates the
Ballard Locks), and Indian tribes\13 to try to control predation by
sea lions and increase the number of returning wild steelhead.  These
efforts to address the predation were taken pursuant to section
109(h)(1)(C) of the MMPA, which allows for nonlethal removal of
nuisance mammals.  Added to the MMPA in 1981, this provision has been
used successfully in other Puget Sound locations to remove California
sea lions from ferry docks by building fences and to chase them away
from federal salmon research facilities. 

Initial attempts to remove sea lions from the Ballard Locks involved
detonating underwater firecrackers.  This attempt resulted in some
initial success but declined in effectiveness as sea lions became
accustomed to the noise.  NMFS and other agencies also tried
capturing sea lions in nets, feeding sea lions dead steelhead
injected with chemicals to make the fish taste bad, and building
barrier nets to keep the sea lions away from the locks.  However,
none of these techniques were effective. 

In 1989, NMFS tried a more extensive approach--capturing and
relocating the sea lions.  Of the 37 sea lions captured and relocated
270 nautical miles away to Washington's outer coast, 29 returned to
Puget Sound.  Some of the sea lions were relocated two and three
times but continued to return.  In 1990, NMFS relocated six sea lions
even further south to their breeding area off the southern California
coast.  However, three of the six returned--one in 30 days, the two
others in about 45 days.  A fourth sea lion returned as far north as
the Columbia River before turning around. 

The most recent attempts to control the sea lions occurred during the
winter of 1992-93, when underwater "acoustic deterrent devices,"
producing periodic uncomfortable sound pulses, were installed near
the locks.  These were improved versions of noise-producing devices
that had previously proved ineffective.  As before, the sea lions
were initially driven away but quickly accustomed themselves to the
sounds. 

Currently, water salinity studies and behavioral studies of steelhead
are under way to better understand their movement through the locks. 
However, Washington State and NMFS regional biologists told us they
were unsure of what additional steps, if any, would be taken.  The
Director of NMFS' Office of Protected Resources expressed optimism
that options not yet fully explored may solve the problem without the
need to consider lethal alternatives, if funding resources can be
made available.  One option not yet tried would involve temporarily
capturing the sea lions when the steelhead are present and then
releasing them afterwards.  This option would entail some risk of
injuring the sea lions during capture, the expense of constructing a
holding facility for the sea lions, and caring for and feeding them
for up to 6 months while in captivity. 

Work has also been undertaken to study possible structural changes to
the locks and accompanying spillway.  In 1990, an interagency
technical committee was convened, comprising representatives from
NMFS, the Washington Department of Wildlife, and the Corps of
Engineers.  The committee did not recommend any structural
modifications but did recommend that fish passage studies be
conducted and that water spill patterns be modified.  The spill
pattern was modified in response.  Lighting experiments have also
been conducted to enhance the night-time passage of steelhead through
the locks.  But according to NMFS, test results were inconclusive
because of technical problems and insufficient numbers of returning
fish to validate the test. 


--------------------
\13 The Muckleshoot and Suquamish tribes have treaty fishing rights
to a share of the Lake Washington wild steelhead run. 


      NONAPPLICABLE AUTHORITY FOR
      LETHAL TAKING AT THE BALLARD
      LOCKS
---------------------------------------------------------- Letter :4.2

Faced with a lack of success in using nonlethal methods to discourage
sea lions from remaining at the locks, NMFS has also examined the
legality of using lethal removal methods.  Washington State and NMFS
regional biologists we interviewed believe that lethal removal of
selected animals could be effective and would discourage remaining
sea lions from staying in the area.  Furthermore, a 1989 NMFS study
concluded that "the lethal removal of small numbers of male sea lions
would have no [detrimental] impact on the population of over 177,000
animals, especially in view of the increasing population trend."

With regard to NMFS' authority to remove sea lions by a lethal
method, section 109 (h)(1)(B) of the MMPA provides for lethal taking
for "the protection of the public health and welfare." This section
has been cited, for example, to permit the removal of sick or
diseased mammals from public beaches.  NMFS examined whether the
authority granted by the section extended to situations like that at
the Ballard Locks but has concluded that it did not have the
authority and that the Congress did not intend the section to apply
in such instances. 

Another section of the act (sec.  101(a)(3)(A)) allows the Secretary
of Commerce to issue a waiver that would permit the lethal taking of
nuisance animals but not until the population reaches its optimum
sustainable population.  However, NMFS officials have not determined
that the population has reached optimum sustainable population as
defined by the act and NMFS' regulations.  According to an April 1992
NMFS report, the rate of population growth has been about 6 percent a
year, indicating a continued potential for absorbing additional
numbers of sea lions within their habitat.  A substantial slowing of
the growth rate, according to these officials, would be a possible
indication that the sea lion population was at or past its optimum
level.  In addition, even if NMFS concluded that the sea lion
population had reached optimum sustainable levels, obtaining a waiver
to allow for lethal takings is not automatic and would not be
accomplished without a potentially lengthy and contentious process of
obtaining public comments on the waiver proposal. 


   MMPA'S AND ESA'S AUTHORITIES TO
   RESOLVE PREDATION OF SPECIES
------------------------------------------------------------ Letter :5

Federal and state agencies' attempts to resolve predation by sea
lions at the Ballard Locks have been undertaken on the basis of
authorities contained in the MMPA.  To date, these authorities, which
permit limited nonlethal human intrusion into predation conflicts,
have not resulted in the successful resolution of predation by sea
lions.  Furthermore, the MMPA's existing authorities for the lethal
taking of marine mammals not at optimum sustainable populations,
according to NMFS, are intended to resolve conflicts between the
protected species and human activity, not to resolve instances in
which a protected species threatens the survival of an unprotected
species. 

The predation of steelhead by sea lions at the Ballard Locks was a
topic of discussion when a group of over 30 organizations
representing both conservation and fishing interests held a series of
meetings earlier this year to discuss reauthorization issues
concerning the MMPA.  The goal of the meetings was to develop
proposed amendments to the MMPA and reach a consensus on specific
language that all the organizations could support.  To address
predation by marine mammals, such as that at the Ballard Locks, the
group developed proposed language amending the MMPA that would allow
NMFS to consider lethal removal of seals and sea lions when they are
identified as habitually exhibiting dangerous or damaging behavior
that cannot otherwise be deterred.  However, only 13 of the
organizations, including both fishing and conservation organizations,
endorsed the specific language of this proposal, which may reflect
the difficulty in reaching consensus on how to effectively address
instances of predation by marine mammals.\14

In July 1993, legislation (H.R.  2760) to amend the MMPA was
introduced in the House of Representatives.  The legislation
incorporated many of the suggestions made by the organization of
fishing and conservation interests, as well as concerns expressed by
NMFS, the Marine Mammal Commission, and other organizations.  To deal
with predation by marine mammals, the bill would require the
Secretary of Commerce to establish a task force to determine the
extent, if any, to which seals and sea lions are affecting salmon
stocks. 

The case of possible adverse predation by marine mammals on Columbia
River salmon, which are protected under the ESA, could lead to a
situation even more difficult to resolve.  Should the predation of
ESA-protected salmon species in the Columbia River by sea lions and
harbor seals be documented as a threat to these species, NMFS will
have to determine how to protect the salmon under provisions of the
ESA and at the same time comply with the MMPA's provisions for
protecting the marine mammals.  It is unclear to us how the
authorities under the MMPA and the ESA would be applied to resolve
this potential adverse predation situation. 


--------------------
\14 An official involved in these meetings informed us that other
groups would have supported the lethal taking provision, but their
concurrence was not obtained because of time constraints. 


   AGENCY COMMENTS
------------------------------------------------------------ Letter :6

We discussed the information contained in this report with
responsible officials of the major agencies involved, including
headquarters representatives of FWS' Division of Endangered Species,
Office of Management Authority, and Division of Fish and Wildlife
Management Assistance; NMFS' Office of Protected Resources; and
regional FWS and NMFS representatives.  These officials generally
agreed with the factual information presented, and on the basis of
their comments, we made changes as appropriate.  As agreed with your
office, we did not obtain written comments on a draft of this report
from the agencies and organizations we contacted. 


   SCOPE AND METHODOLOGY
------------------------------------------------------------ Letter :7

To obtain information on the extent to which species protected under
the ESA and MMPA were adversely affecting nonprotected species, we
held discussions with NMFS and FWS headquarters and regional
officials.  We also met with officials of the Washington State
Department of Wildlife and the State of Maine Atlantic Sea Run Salmon
Commission and discussed predation issues with officials of the
Pacific States Marine Fisheries Commission, the Center for Marine
Conservation, the Marine Mammal Commission, and the Northwest Indian
Fisheries Commission.  We conducted our review between January and
July 1993 in accordance with generally accepted government auditing
standards. 


---------------------------------------------------------- Letter :7.1

As arranged with your office, unless you publicly announce its
contents earlier, we plan no further distribution of this report
until 30 days from the date of this letter.  At that time, we will
make copies available to the Secretary of Commerce, the Secretary of
the Interior, and other interested parties.  We will also make copies
available to others on request. 

Please contact me on (202) 512-7756, if you or your staff have any
questions.  Major contributors to this report are listed in appendix
I. 

Sincerely yours,

James Duffus III
Director, Natural Resources
 Management Issues


MAJOR CONTRIBUTORS TO THIS REPORT
=========================================================== Appendix I


   RESOURCES, COMMUNITY, AND
   ECONOMIC DEVELOPMENT DIVISION,
   WASHINGTON, D.C. 
--------------------------------------------------------- Appendix I:1

Paul O.  Grace, Assistant Director
Thomas A.  Heck, Assignment Manager


   SEATTLE REGIONAL OFFICE
--------------------------------------------------------- Appendix I:2

Laurence L.  Feltz, Regional Issue Area Manager
William E.  Hanson, Evaluator-in-Charge
Stanley G.  Stenersen, Evaluator

