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Baird's beaked whale stranded at La Push, WA in January
2003
On
Tuesday, 28 January 2003, a large beaked whale carcass was reported to have
washed ashore on Second Beach at La Push, WA. The Northwest regional marine
mammal stranding network dispatched Ken Balcomb (Center for Whale Research,
Friday Harbor), Todd Chandler (Cascadia Research Collective, Olympia), Laurie
Hopkins (NMFS) and Dr. Stephen Raverty (DVM Pathologist, Abbotsford, BC) to the
scene to identify the species, collect specimen materials, and determine the
cause of death, if possible.
The stranding response team arrived on scene in
mid-day as the tide ebbed on 30 January and performed a necropsy on site. The
whale was 11.77 meters (38 feet) in length, identified as a Baird¹s beaked
whale, of undetermined sex and age. The genital region had extruded and
decomposed, and gonads were not located; but, tissue chromosomes will later be
analyzed to determine sex, and laminations in the cemental layers of a tooth
will be analyzed to determine age. The stomach contained bony remains of many
small fish, and the blubber thickness indicated that the whale had been feeding
and was in good body condition immediately prior to death. Tissues will be
examined for any evidence of disease process.
The right shoulder blade and many
ribs were broken, some internal organs were displaced, and the head and
acoustic fats in the mandibles and forehead were seeping blood. Although it was
not determined in the field if these traumas were antemortem or postmortem
(before or after death), that may be evident from analysis of collected specimen
materials. Grossly, the evidence suggests massive blunt trauma, for example
from ship strike or explosion nearby. If the whale suffered a ship strike while
alive, this would be the first record of such an incident involving a beaked
whale species that is normally shy and avoiding of vessel traffic. In any case,
this whale represents the second record of Baird¹s beaked whale from Washington
State, the first being noted by Slipp and Wilke (1953) of this uncommon deep
diving North Pacific whale species.
The entire whale is estimated to
have weighed twelve tons and could not be moved by the response team, but the
head (weighing approximately 700 pounds) was removed and dragged above the high
tide line for later examination. Rising tide, storm conditions, and approaching
darkness precluded further examination on 30 January, and most of the response
team departed around dusk.
On
31 January 2003, Ken Balcomb returned at mid-day to further examine the whale
and collect the earbones, which could provide additional evidence concerning
whether the whale had experienced an intense pressure trauma in vivo (while
living). This is very important to ascertain because beaked whales seem to be
especially sensitive to pressure trauma, such as are experienced during
underwater explosions, seismics, and sonar operations. [It is extremely interesting,
and perhaps germane to note that the US aircraft carrier, USS ³Carl Vinson²
(CVN70)² and its frigate escort, USS ³Ingraham² (FFG61) departed Puget Sound on
or around 22 January, 2003 for two weeks of sustainment training in the eastern
Pacific prior to arriving in Honolulu on 2 February 2003; see http://www.cvn70.navy.mil/.
I do not know if active sonar was employed during the transit phase of this
deployment, but ³Ingraham² is equipped with ANSQS56 mid-frequency sonar, which
is capable of producing 6.8-8.2 kHz ³pings² at a nominal source level of 223 dB
(at least). We had noted that ³pings² of high intensity medium frequency were
recorded from the Sea Sound hydrophones in Haro Strait on 22 January, as an
aircraft carrier was observed heading west in the eastern Strait of Juan de
Fuca late in the day; but, we do not know if this was USS ³Carl Vinson² and
escorts. It is further interesting, and perhaps germane, to note that there is
a US Naval exercise area nearby, designated W237, within the Olympic Coast
National Marine Sanctuary, just offshore of La Push, Washington. There should
be records available if there was exercise activity in this area around this
time, and if so what was the nature of that activity. This could shed light on
the tremendously important topic of sonar impacts on marine mammals in
Washington State and throughout the world.]
The earbones will be subjected to Computerized Tomography (CT) scans and subsequently decalcified and examined
histologically. Specifically, the presence of eosinophilic precipitate
(indicating an antemortem insult), blood in primarily the apex and base of the
cochlea (suggesting a neural canal and CSF entry to the ear), loss of
auditory neurons and metabolic tissues, and labyrinthine
collapse², if present, would be consistent with impulse trauma as previously
demonstrated in beaked whales as a result of sonar operations. Alternatively,
the whale could have experienced an unexpected and immaculate death, and simply
bashed onto the rocks before stranding on the sandy beach.
Ref: Slipp, J. and Wilke, F., 1953.
The beaked whale Berardius on the Washington coast.
J. mamm
. 34, 105-113.
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