|
Marine
Biologist Ken Balcomb's
|
Comprehensive
Retirement Plan
from The Center for Whale
Research
|
A
pre-proposal to return and rehabilitate a captive killer
whale named Lolita to her home waters in Greater Puget Sound.
Prepared
by Center
for Whale Research
Friday Harbor, WA 98250 April, 1995
Our
Aims:
1)
to reach a sensible business agreement with Lolita's owner(s)
to retire her from show business and transport her back
to her home waters to live out the remaining years of her
life in a natural setting. In doing so, the paramount factor
will be to ensure Lolita's health and well-being in cooperation
with those who know her best.
2)
to acclimate Lolita in a natural seawater pen and train
her to "gate" to open water of Greater Puget Sound, much
like the training accomplished by the US Navy for dolphins
and killer whales (see: Bowers and Henderson, 1972).
3)
to conduct comprehensive DNA, veterinary, and physiological
studies of Lolita before, during and after her transition
to home waters to determine the genealogy, relative health,
and physiological demands of captive versus that of free-ranging
whales.
4)
to contribute to our understanding of the science of reintroducing
cetaceans to the wild: whether or not she actually returns
to her family, she can provide valuable information on foraging
ability and free-ranging behavior of an ex-captive.
5)
to ascertain whether a whale can remember and respond in
its native dialect after long term separation from its family.
6) to allow Lolita to return completely to a free-ranging
state with her family members, if she so chooses (reintroduce
her to the wild), or to simply provision her and provide
veterinary care while allowing her to free-range and return
at will to a "sea-pen" location in which she feels secure.
7)
to potentially recall Lolita at intervals from her free-ranging
or reintroduced state to ascertain her continuing health
status, and to obtain information about her environment
via medical and instrument sampling.
8)
to determine whether Lolita can acquaint other free-ranging
whales with trained behaviors that may be of scientific
value to us or survival value to them (e.g.. Can she introduce
them to feeding sites or behaviors which permit close observation
or veterinary care?).
9)
to boost public awareness about marine conservation and
the unique role of these remarkable cetaceans in the marine
ecosystem.
Background
and Significance
Why
retire Lolita and subject her to a research project now?
Killer
whales are actually large dolphins and are naturally very
social and cooperative top marine predators, with highly
evolved communication and mental processing abilities. They
are specialists that strategize and cooperate with one another
in very complex foraging situations, and they develop very
long-term functional relationships with other whales (and,
sometimes with people). With other whales these relationships
begin along matrilineal lines, and subsequently extend to
more distant kinship groups within a clan. Gametes disperse
throughout the clan, but the individual whales, both male
and female, remain in their natal matriline for life. This
functional family approach to successful cooperative predation
which they have evolved over millennia is now very obvious
in field studies, yet this species' modern captive display
in show business routines does little to depict it. On the
contrary, the display is much like a marine circus with
whale and human entertainers doing spectacular tricks together,
and there is some controversy over whether that is appropriate
display. Most of the whale entertainers were removed from
their wild family at a very young age and forced into artificial
social groups for these displays, or more recently for display
and captive breeding purposes.
Killer
whales are not an endangered species, and currently there
is no management need to breed them for reintroduction,
although reproductive and captive studies are of scientific
interest and may have management value in the future. There
has been recent discussion of reintroducing killer whales
and other dolphins for humanitarian or management purposes,
but the subject is controversial.
In
the particular case we bring up - that of Lolita - captivity
is primarily for public display and entertainment purposes,
as her facility has no other killer whales and since 1981
has made no application to acquire any. Her case is controversial;
but, nonetheless it represents a major concern for the whale
and an image problem for the captive display industry that
for the past fifteen years she has been essentially in solitary
confinement in an outdated, inadequate and deteriorating
facility in a program of limited educational or conservation
benefit to the public. It is a case like that of Ivan, a
gorilla that spent twenty years in a solitary cage in a
shopping mall in Tacoma until last year.
Both
Lolita and the Miami Seaquarium where she is housed are
victims of changing demographics of South Florida tourism,
with diminishing revenue for improving the situation and
not much to look forward to in the economically foreseeable
future. The facility is subject to severe damage from natural
disasters such as the devastating Hurricane Andrew which
caused the death of several of her fellow captive marine
mammals. During that storm, her water filtration and cooling
system were temporarily knocked out, and enormous jacks
now support the concrete stadium around her, with puddles
of seawater gathering around the leaking floor. It is likely
that no marine park is currently willing to buy Lolita,
because in their view she is approaching maximum longevity
(which is statistically probable if she remains in captivity),
and many think she is past her reproductive prime for captive
breeding purposes. We are not privy to her owner's specific
plans for Lolita, but we are concerned for her future and
are trying to offer a plan before it is too late. We are
also trying to anticipate future information needs in the
science of cetacean reintroduction and in marine ecosystem
management particularly as it pertains to this whale's home
waters of Puget Sound. Lolita is perfect for both purposes,
as we hope to demonstrate.
From
our review of cetacean releases to the wild, mostly of dolphins
(but including short-term captive releases of killer whales),
and from discussions with marine mammal veterinarians, trainers
and collectors, we suggest that these animals can be viably
returned to the natural state, where longevity may be greatly
increased. Dolphin releases have been successfully done
even after prolonged captivity lasting more than a decade
(for examples, see: Cetacean Releases, DRAFT 1994), but
they have often been uncontrolled and/or without sufficient
follow-up. There is a general need to develop a scientific
protocol for increasing the probability of successful reintroduction
of cetaceans in the future for both management and rehabilitation
purposes. There is also political support for developing
such a protocol: for example, in response to a Congressional
request, the United States Navy (NRaD) recommended, among
other things, that the Navy establish reintroduction as
an exploratory initiative and foster the research and development
of the necessary methods and technologies (Brill and Friedl,
1993).
In
summary, the cumulative economic, demographic and biological
risk factors appear greater to Lolita's survival and less
humane in her present artificial surroundings in Florida
than those resulting from bringing her back to her home
waters of Washington State for potential reintroduction
to her natural habitat and family. There is also a strong
scientific and political incentive to begin developing a
proposal to do just that. The merits of such a proposal
are objectively clear when one considers the improved knowledge
such a program will provide in the science of reintroduction
such as has been called for, and the constructive benefit
to the resident whales from the media attention generated
(e.g.. The huge promotion of the importance of maintaining
a healthy ecosystem for the whales and their prey resources).
The attention can also generate revenue potential for the
Miami Seaquarium.
Why
Lolita? Aren't there other whales in captivity to pick on?
Lolita
is a native daughter of Washington, and is the last survivor
in captivity from the Washington State population. Her free-ranging
extended family has also survived, is well documented and
is year-round "resident" to Greater Puget Sound, and they
can be located in this habitat much of the time. This is
a very unique situation, and it is not the situation for
any other cetacean in captivity. In fact, Lolita probably
offers the most unique opportunity for a rehabilitation
and reintroduction study of any cetacean ever in captivity,
and arguably her quality of life will be improved if she
was made available for such study.
What
specifically is known?
Lolita
(AKA Tokitae) was captured on 8 August 1970 at Penn Cove,
Whidbey Island about forty miles north of Seattle. She was
a member of the southern resident community of killer whales
(AKA orca, from the scientific name Orcinus orca) that frequent
the Greater Puget Sound marine habitat. Lolita was one of
seven young whales sold to marine parks around the world
in this roundup of virtually the entire population. From
more than a dozen such captures, approximately 58 young
whales were removed, and approximately 68 mostly older individuals
remained. Due to a Federal court order, and public resistance
to further removals, no captures have occurred in the Greater
Puget Sound region since 1976, and the population is now
recovering and estimated to return to pre-exploitation size
by the end of this century. All captures since 1976 have
taken place in Iceland, and most of the killer whales in
captivity are now Icelandic, or genetically mixed offspring
from Pacific and Icelandic whales. The Icelandic whale population
has not been well studied, and the logistics of rehabilitation
and reintroduction study off Iceland are formidable, if
not impossible due to that government's stance on whaling
and animal issues.
Lolita
was sent to the Miami Seaquarium in Florida in September
1970, to share a pool with a young male whale named "Hugo"
captured in Puget Sound in 1968. The six other young whales
exported from her capture went to parks in Texas, Australia,
Japan, France, and the United Kingdom. All six, and Hugo,
have since died. Whereas, natural lifespan in the wild is
currently estimated at 50 80 years (Olesiuk, et. al., 1990),
all of these young animals died prematurely in their teens
or younger. It is a sad fact that no whale lifespan in captivity
has yet approached the average lifespan of these animals
in the wild. The arbitrary breaking of bonds and mixing
of whales from different populations in small enclosures
to satisfy entertainment and breeding requirements may be
causing a well-masked stress response which reduces survivability.
The captive population is unlikely to produce animals suitable
for future reintroduction in the current breeding scheme.
In
any population, however, a few individuals are potential
survivors of extreme situations, including those encountered
in transport and captivity. Lolita is obviously one of these
hardy survivors, perhaps in part because of her relatively
advanced age at capture. She was about 15 feet long and
six to seven years old in 1970, and is now a mature nulliparous
adult about 31 years of age. She is approximately 22 feet
in length, weighs about 8,000 pounds, and is reported to
be in excellent physical health. Judging from her survival
to date and her veterinary reports, she receives excellent
care, quality food and training, and she is alert and responsive
to people who come to see her shows. She has adapted well
to human control. Even her owners admit, however, that her
pool is too small, outdated, and seriously in need of maintenance.
It is an 80' oval pool 12 20 feet deep filled with natural
seawater that is drawn from Biscayne Bay and chilled to
about 65 degrees F. The pool was severely damaged by Hurricane
Andrew, and with just a little push from another hurricane,
her entire physical support system could fail. Unfortunately,
we see no feasible backup plan for her survival, except
to move her to even less adequate tanks on site or perilously
move her to another marine park in the event of another
disaster. That is not really a viable plan for Lolita's
long term benefit, so we propose developing one.
The
Proposing Institution
The
Center for Whale Research, Inc. was founded to promote,
support and conduct benign scientific research on marine
mammals of the Order Cetacea - whales, dolphins and porpoises.
The research methodology is primarily that of photo identification
in population and behavioral studies in the wild. Photo-identification
relies on the demonstrated permanence of pigmentation and
scar patterns which are extremely reliable, for example
in killer whales. The knowledge gained from these studies
is provided to governments, to the public and to conservation
organizations.
The
Center is funded by contributions from individuals and organizations,
occasional grants, sales of whale related items, and contracted
studies. It is incorporated as a non profit organization
in the State of Washington with IRS 501 (c)(3) tax deductible
status [EIN 91 1334319].
The
principle studies underway as of 1995 are the Orca Survey
- a long term photo identification study of killer whales
in the Pacific Northwest since 1976; and, the Bahamas Marine
Mammal Survey - a general survey of marine mammals in the
Bahamas Islands, with particular emphasis on photo identification
studies of bottlenose dolphins, pilot whales, and beaked
whales. Other studies include collaboration on population
studies of humpback and blue whales in the North Pacific
Ocean, and development of technologies and techniques for
benign studies of free-ranging cetaceans. Much of the Center's
fieldwork is conducted in cooperation with Earthwatch, a
Massachusetts based volunteer environmental organization.
The
Center is staffed by a full time volunteer director, a volunteer
publicist, and five part time volunteer researchers. Over
ninety percent of the Center's budget is spent on program
activities. For purposes of this project, if a scientifically
responsible plan is developed and approved, the Center will
undertake dedicated fundraising and will solicit extensive
collaboration with Pacific Northwest zoos and aquaria, the
Miami Seaquarium, and agencies in the State of Washington
to bring Lolita home.
The
staff and volunteers of the Center are keenly interested
in the well-being of all whales and dolphins, both in the
natural state and in captivity. Lolita potentially bridges
the gap that has developed between captive marine mammal
research and research on a free-ranging population quite
nicely. As a result, she offers the sciences of Zoology
and Reintroduction Biology a most unique opportunity.
Why
do we think Lolita has a family to return to?
What
is known of her family?
The
Southern Resident Community of killer whales is comprised
of three pods, J, K, and L. This population now totals 94
in mid-August of 1995, which is roughly 39% higher than
its size of 68 when we censused it in 1976. All three southern
resident pods were cropped during 1967 73 in a live capture
fishery for aquaria. At least 44 of the 58 removals were
of southern residents, mostly immature whales that were
taken or killed during captures in this period. Perhaps
up to 14 whales that were taken or captured were so-called
Transients that are genetically distinct and have a range
from Alaska to California. A photographic catalogue of both
residents and transients was published by Bigg, et. al.
(1987), and the resident catalogue has been recently updated
by Ford, et. Al. (1994). Photographs taken during Lolita's
capture demonstrate that she came from a southern resident
pod; she is therefore genetically compatible with the region's
population.
The
southern resident pods are seen regularly during the summer
in the protected inshore waters of Georgia Strait and Puget
Sound, especially in the vicinity of Haro Strait, west of
San Juan Island, and off the southern tip of Vancouver Island.
Southern residents, especially K pod and L pod, frequently
make excursions out of Juan de Fuca Strait to areas off
the west coast of Vancouver island and the Olympic Peninsula,
where they forage amongst commercial trollers on the offshore
banks to catch salmon. In September and October, all three
pods can often be found off the mouth of the Fraser River
in Georgia Strait, intercepting late season runs of salmon
before they enter the river. During the winter, J pod is
the most commonly sighted pod in inshore waters, especially
in the Alki Point, Vashon Island and Pt. Defiance areas.
Even during salmon season, these whales are known to eat
species of fish other than salmon, and their population
is probably prey resource limited by the year-round availability
of non-salmonid as well as salmonid species.
From
twenty years of detailed individual photo-identification
study, we have learned that the southern resident killer
whale society is matrilineal and apparently matriarchal.
No offspring has been observed to emigrate from its natal
pod, nor have any immigrated. The maternal bond is quite
strong and apparently life-long, as for example in elephants.
Average longevity in this population is calculated to be
29-50 years, males and females respectively, and sexual
maturity in both sexes occurs in the teens (Olesiuk, et.
Al., 1990). Social maturity for males occurs in late teens
or early twenties. Sexual activity is precocial, mating
is presumed to be polygynous, but paternity is not known.
mtDNA studies now underway may soon reveal fascinating detail
to overlay the observational studies (see, for example,
Amos, et. Al., 1991). They will in all probability also
reveal Lolita's matrilineal affinity.
What
have we done so far, and what steps need to be taken?
Our
greatest concerns are for the long term well-being of Lolita,
the pods to which she may be reintroduced, and the cause
of conservation and wise management of Greater Puget Sound
marine resources. We wish to take all possible precautions
to minimize risk or suffering to Lolita in development of
this proposal. As in the case for Ivan the gorilla, we have
to approach this whole project with the mindset that we
have a naturally wild but socially deprived animal in our
care, and we have to keep its best interests in mind. From
a captive wild animal's point of view, our wishes and efforts
may be irrelevant. It may long for freedom, and savor its
remembrance, or it may accept the free meals and medical
plan, ad hoc. But, in almost all cases where the option
is available, creatures in captivity prefer being with others
of their kind over solitary confinement. That is the humane
standard of captivity. Where possible, the choice should
be left to the wild animal involved whether it should remain
alone. In that, Lolita may be a most unique cetacean candidate,
being large-brained and potentially vocally communicative.
We are encouraged from the recent successful reintroduction
of the captive gorilla, Ivan, to the company of other gorillas
following over 20 years in a solitary cage in a shopping
center. Ivan quickly adapted to his new social setting in
a new environment and mated with a female gorilla within
x days of his reintroduction.
Several
steps need to be taken prior to proposing that anyone transport
the captive whale Lolita from the Miami Seaquarium to her
native waters for rehabilitation and potential reintroduction.
These can be logically divided into several phases some
of which may run concurrently: 1) developing a detailed
scientific and husbandry protocol that meets the professional
standards of the zoological display industry; 2) gaining
public support (including permission from the owner of Miami
Seaquarium) for a whale rehabilitation/reintroduction project;
3) selecting a sea-pen site or sites and meeting government
criteria for rehabilitation/reintroduction of a marine mammal;
4) conducting pre-transport evaluations and experiments,
including acoustic experiments to assess potential recognition
by her pod; 5) assembling a team of specialists to actually
carry out the transport and acclimatization of Lolita; and,
6) including sufficient safeguards such that any actual
return to the wild will be up to Lolita, not us or other
parties.
The
success of each phase of the project will help determine
the timing and procedures for subsequent phases. For example
the degree of apparent mutual recognition elicited by the
acoustic experiment will provide data on which the proposed
timing of the eventual transport and potential reintroduction
will be based. A short term experiment to determine if Lolita
can and will pursue and devour live fish in her tank, similar
to an experiment conducted by Newman and Markowitz (1993)
at Marine World Africa USA in California in 1993, may also
be done. In that experiment, the two whales, which had been
in captivity for 24 and 13 years, immediately echolocated
on, caught and ate the fish. If such an experiment is permitted
by the owner, allowing Lolita to catch live fish may be
continued as environmental enrichment even after the results
of the experiment are known.
Broad
based political support for the project will be important
in all phases for several reasons. Many areas of oversight,
experience and expertise will be relevant to various aspects
of the project, and a generally supportive public will encourage
help from the scientific community, permitting and supervisory
agencies, land owners, possible funding sources, and others.
Widespread public interest in the project will also help
to fulfill an important objective: To draw attention to
the whales that live in and depend on the waters of Puget
Sound and thereby engender a sense of stewardship toward
them and their ecosystem.
When
the whales' health and well being are an important consideration,
the overall health of the Puget Sound marine ecosystem will
become important for the public to understand and improve.
For example, the whales' need for bountiful salmon and other
fish runs requires that wetlands, streambeds and rivers
be productive for them to simply eat. We know and otherwise
suspect that PCB's and other contaminants build up in whales'
fatty tissues and may cause reproductive failure or firstborn
neonate mortality. From a general awareness of these ecosystem
effects, the public will be more concerned about point and
non-point pollution, oil spills and other sources of contamination
that must be prevented to ensure water quality. Whales,
especially a star whale like Lolita returning home, can
help rally active concern to protect and conserve natural
resources.
For
the millions of people who will follow Lolita's progress
back to her native waters and reunion with her family, the
health of her habitat and her prey sources will become generally
known. Lolita is not only a unique individual; she is a
unique vehicle to understanding and appreciation for marine
conservation.
Examples
of some scientific experiments that might be conducted with
Lolita's help.
1)
DNA studies for genealogical relationships. mt DNA from
blood or biopsy samples will further confirm Lolita's origin
as well as improve general understanding of free-ranging
pods. mtDNA studies using skin samples are already underway
in free-ranging populations in Prince William Sound, Southeast
Alaska, northern British Columbia, and in offshore, transient,
and southern BC/Washington. In September, 1995, biopsy studies
for DNA analysis will commence in Washington State. Potentially,
all of Lolita's immediate living relatives will soon be
known. It is vital that holders of animals in captive populations
contribute samples from their animals and make the results
available for scientific and conservation purposes. We suggest
that for this, all Icelandic whales should be sampled, and
all genetic crosses should be studied in detail. This information
is very important to science, and should not be considered
proprietary.
2)
Communication studies. As a first step in reintroducing
Lolita to her pod, we propose playback experiments to Lolita
from recordings of several pods to look for recognition
of her native dialect. We also propose making recordings
of Lolita's vocalizations for playback experiments in the
vicinity of her extended family to look for response. Based
upon results of those experiments, we anticipate further
proposing establishing a live two way communication link
via satellite between Lolita's tank in Miami and her extended
family in Puget Sound. Orca pods and communities share vocabularies
of calls, and we believe that when she hears her family's
characteristic vocalizations, Lolita will recognize them
and vocally respond. This interaction will help establish
the level of recognition between Lolita and her family,
and may help prepare her emotionally for reintroduction.
3)
Physiological studies. Physiological techniques and telemetry
have advanced significantly since the US Navy conducted
studies of free-ranging killer whales in the late 1960's
and early 1970's (see: Bowers and Henderson, 1972; and Ridgeway,
1972 versus Mate, 1989; and Goodyear and Andrews, 1993).
It is now technically feasible to instrument a free-ranging
whale using benign suction cup attachment of physiological
and other transducers and computer memory chips to send
data back via radio signal, either with line of sight or
satellite relay. Lolita can be trained to gate, range freely,
and return to the security of her enclosure, all the while
sending information such as body temperature, heart rate,
acoustic emanations, brain wave patterns, depth of dive,
oceanographic and ambient acoustic conditions. In routine
medical examinations before and after free-ranging experiments,
she can present urine, blood samples, respiratory air samples,
etc. for unprecedented access to information regarding the
physiological state of a captive versus free-ranging killer
whale. The US Navy is doing similar studies with dolphins,
and potentially has interest in obtaining information on
this larger species of cetacean.
When
we examine the Navy criteria (Brill and Friedl, 1993) of
attributes for a candidate for a reintroduction program,
we find that Lolita is very nearly ideal:
1)
exact knowledge of its group and location from which the
animal was acquired is known.
2)
the animal was collected in the wild (not captive born).
3)
the animal was self-sufficient before acquisition.
4)
in terms of the animal's age at reintroduction, there is
a low risk of mortality (Lolita is in her prime of life).
5)
the animal is socially competent (Lolita has lived for six
years with her family, for ten years with Hugo, and for
the past fifteen years with other cetaceans).
6)
if made available for return to a sea-pen and free-ranging
studies in Puget Sound, the animal will have had experience
in a variety of environments.
7)
the animal exhibits flexible responses to novel and varied
environmental conditions.
8)
the animal's behavior is readily modified through the standard
techniques of operant conditioning.
9)
the animal exhibits no aberrant behavior.
10)
the animal is in excellent health and physical condition.
11)
the animal has not been exposed to any life-threatening
diseases.
When
we consider questions concerning whether it is more humane
to return Lolita to her home waters versus leaving her in
her solitary tank in Miami, whether it is more humane to
transfer Lolita to another marine park and the company of
unrelated animals of her species or return her to her family,
and whether it is more appropriate to display her for entertainment
purposes or employ her in a scientific development of reintroduction
procedures and inquiry into her species ecological requirements,
we get into controversial areas of discussion; but, we nonetheless
consider Lolita the ideal candidate for such discussion,
and we hope that science, conservation, and her species
will benefit from it.
Concluding
Remarks
There
is probably no more appropriate forum for such discussion
of reintroduction of a captive killer whale to its home
waters in the Pacific Northwest that in the 1995 Annual
Meeting of the AZA in Seattle this September. A major topic
of discussion at this meeting will be reintroduction of
zoological specimens to wild populations, pros and cons.
The peer group of assembled AZA experts have the most expertise,
and the most at stake, aside from the animals themselves.
The Governor of Washington State has called for discussion
with Miami Seaquarium on the subject of returning Lolita,
because she is the last remaining native daughter in captivity,
and she offers the key to arousing tremendous public interest
in the conservation and preservation of the Greater Puget
Sound marine environment. We hope that this pre-proposal
is seriously considered by AZA participants as a way of
bringing their aquarium colleagues into step with current
attitudes regarding their role in conservation. These creatures
are more than circus actors for entertainment, they are
important for public education and conservation purposes;
and, their maintenance must be in accordance with humane
standards.
References:
Amos,
B., J. Barrett and G.A. Dover, 1991. Breeding system and
social structure in the Faroese pilot whale as revealed
by DNA fingerprinting. Rep. Int. Whal. Commn. (Special Issue
13), pp. 255-268.
Bigg,
M.A., G.E. Ellis, J.K.B. Ford, and K.C. Balcomb, (1987).
Killer whales, a study of their genealogy and natural history
in the Pacific Northwest. Phantom Press, Nanaimo (out of
print).
Bowers,
C.A. and R.S. Henderson, 1972. Project Deep Ops: deep object
recovery with pilot and killer whales. NUC TP306, US Navy,
pp. 1-86. Unclassified, but hard to find.
Brill,
R.L. and W.A. Friedl, 1993. Reintroduction to the wild as
an option for managing the Navy marine mammals. Technical
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Cetacean
Releases, DRAFT 1994. Published by the Center for Whale
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Ford,
J.K.B., GE Ellis and K.C. Balcomb, (1994). Killer whales,
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Columbia and Washington State. UBC Press, Vancouver, pp
1-102.
Goodyear,
J.D. and R. Andrews, 1993. The first whale ECG with a self-contained
tag and radio and satellite-linked depth and heart-monitoring
tags for whales.
Mate,
B., 1989. Satellite-monitored radio tracking as a method
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Newman,
K. and H. Markowitz, (1993). Echolocation by killer whales
while in pursuit of live fish. Abstracts, Tenth biennial
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Marine Mammalogy.
Olesiuk,
P.F., MA Bigg, and GE Ellis, (1990). Life history and population
dynamics of resident killer whales (Orcinus orca) in the
coastal waters of British Columbia and Washington State.
Reps. Int.f Whal. Commn. (Special Issue 12): 209-248 Ridgeway,
S., 1972. Homeostasis in the aquatic environment. [In]
Ridgeway,
S.H. (Ed.), Mammals of the Sea, biology and medicine, Charles
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