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Raincoast
Research commenced a long-term study on the acoustics and natural
history of killer whales, orca, in the Broughton Archipelago in
1984. This region, between Kingcome and Knight Inlets provided protected
marine habitat, including inlet, archipelago and estuarine environments.
An underwater hydrophone monitors the heart of the archipelago where
four major waterways intersect and whales passed frequently. All
whales are identified, either through photo-identification or audio
recordings when they pass at night. Both resident and transient
orca use the area and on one occasion an offshore group was encountered.
While
many groups of transient whales are encountered hunting primarily
harbour seals and harbour porpoise, but also Steller sea lions and
dolphins, among the northern resident whales, the area "belongs"
to the "A" pods. If other pods came through, they were generally
escorted by an "A" pod member. In April and May members of this
group could be seen entering the inlets at the time of the oolichan
spawn. Oolichans are an oil-rich member of the smelt family tied
closely with First Nation tribes who made "grease" from these fish
an essential food and trade item. The whales don't appear to eat
the oolichans, but the chinook salmon do and these large fish follow
the oolichans and are in turn pursued by the whales.

Oolichan
(© Alexandra Morton, ink)
In
June whale activity diminished. But in July through October, when
large assemblages of orca gather in the salmon-rich adjacent waters
of Johnstone Strait, individual families used the area to sleep,
feed and relax for a day before re-entering the Strait. Whales swim
while sleeping, shutting down one side of their brain at a time.
Their pattern was to enter Fife Sound at the beginning of the ebb
tide, fish until Tribune Channel, then sleep all the way down Tribune.
This channel is straight and deep, no sudden obstructions, the ebb
tide slowed their progress and carried scents of what lay ahead
- the perfect place for a whale nap. While pebble beach chatter
underwater, tidal action roars, speedboats scream and big ships
and tugs obliterate all other sound - the inlets were completely
silent. Whale calls echoed six times in some places like the ringing
of church bells.
In
winter when salmon are no longer running in schools as big as rivers,
the whale families breakdown into their smallest divisible units
- mothers and offspring. In many killer whale groups everyone stays
with mom for their entire lives. If families are small two sisters
sometimes swim together with their collective children and grandchildren.
In winter the whales hunt for bottom fish, and the inlets provide
sheltered water and a rest from the windy winter weather of this
coast.
In
1993 the salmon farming industry introduced underwater sounds designed
to hurt the ears of seals and repel them. The whales vanished to
protect their sensitive and essential hearing - ending thousands
of years of passage through this archipelago. All the inlets of
this coast are likely "claimed" by whale families and whether another
let the "A" pods in is unknown. In 1999, the salmon farms turned
off their noise, but the whales do not trust the silence yet. Raincoast
looks forward to the day Tsitika, Yakat, Scimitar and the others
reclaim the Broughton.
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Arrow, a young transient male swims up Cramer Pass
with his mother (© Alexandra Morton)

Orca
call

Group
spyhop (©
Alexandra Morton)
Killer
whales love to perform activities precisely together. This begins
at birth when infant whales learn to open the blowholes to breath
at the surface with their mothers. This group spyhop demonstrates
one of the mysteries of the orca - do they have ritual-like behaviours?
Orca love a good sunset and sunrise and this photo was taken as
shafts of sunlight pierced a thick cloud bank over Alert Bay sending
radiant bars of light to the sea. This kind of activity has also
been observed in captive whales "greeting" the sunrise.

Transient
orca in winter (©
Alexandra Morton)

Two
orca (© Alexandra Morton, ink)
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