TOM HEVEZI/THE CANADIAN
The behaviour of northern bottlenose whale
is the most visible way scientists have of determining the relative health of
the Sable Gully, the largest submarine canyon in eastern North America.
Whales in Sable
Gully helping scientists protect ecosystem
HALIFAX - An
endangered species of whale that can dive as deep as a kilometre to feed is
helping scientists determine how to protect an unusual marine ecosystem off
Canada's East Coast.
Observations of northern bottlenose
whales in the Sable Gully - the largest submarine canyon in eastern North
America - are proving to be an effective way to determine the health of the
area, federal Fisheries Department scientists told a news conference Monday.
"If the whales are doing well, we can probably assume
that the underlying ecosystem is still fairly robust and supportive'" said Paul
McNab, who manages the marine protected area about 200 kilometres southeast of
"Whales become a fairly easy study indicator
because you can go out there on the surface and take photographs, you can count
whales, you can look at whether they are still reproducing."
A group of marine scientists recently completed a
two-week trip to the gully to study deep-water animal life, some of which makes
up the diet of the northern bottlenose.
complemented an earlier study, carried out in July, in which sci entists used a
submersible to probe the depths off Nova Scotia and Newfoundland.
The small, remotely controlled sub was used to capture
pictures of rare corals and fish that inhabit the dark, craggy floor of the
Lead scientist Trevor Kenchington said the more
recent trip, which wrapped up last week, involved the use of the Canadian Coast
Guard vessel Wilfred Templeman, which captured marine life in a trawling net
that was pulled about a kilometre under the surface.
60-metre-wide net was pulled through the gully, but it never came close to the
bottom, Kenchington said.
More than 220 species of fish,
squid and various shrimp-like crustaceans were lifted to the surface.
"I've been a marine scientist for about 30 years (and) I
have never known a single trip to sea to get us as much knowledge as this one
aid," said Kenchington.
Many of the species observed were
recorded for the first time in Canadian waters, although the scientists were
unsure whether any of them are "totally new" to science.
Kenchington said one "weird and wonderful" creature was
particularly puzzling. "It looks like somebody put a filet of smoked salmon
into the net. It's about the consistency of rather thick Jell-O and none of us
have a clue what it is:'
Other creatures caught in the
net included lanternfish, a tiny fish with big eyes that emits a bluish light
to hide from predators as it emerges from the depths to feed near the surface
From greater depths, scientists came face to
face with several ghastly predators, including the aptly named ogre fish. While
adults are only about 15 centimetres long, their menacing fangs make them look
like something conjured for a horror movie.
world down there: lots of horrible looking, but quite small predators waiting
for things like the lanternfish to come swimming down to be swallowed," said
The catch also included plenty of"weird
squids", including the armhook, a squid with hooks like cat claws. It is one of
two species of squid that comprise the main diet for the bottlenose whale.
Kenchington said by learning more about the gully's
creatures and what sustains them, scientists will have a better idea of what to
"We do know the whales are there and we know the
whales are important to Canadians. We know they are feeding, therefore we
really want to know why their food is there:'