26th October 2007
The body of a minke whale (Balaenoptera acutorostrata),
that washed ashore on the south coast of
Cornwall has been examined by volunteers from the Cornwall Wildlife
Trust's (CWT) Marine Strandings Network. The whale was first seen
floating offshore several days before and was reported to have a
large gash in its head.
"There was little we could do until the whale beached", said Maddie
Precious, one of the coordinators of the Network, "but it did
finally strand on the Roseland peninsular and we were able to record
it. HM Coast Guard were naturally concerned about the risk to
shipping of such a large, heavy object, so we're all relieved to
know where it is!"
The whale was found to be a female. "She was lying on her right side
in the sand" said Jeff Loveridge, one of the CWT volunteers who
helped to record the whale. "It was quite sobering to see such a
magnificent animal in that state but, at the same time, it gave us a
chance to get a rare look at one of the smallest whales. The
minke
whale is quite small compared to other filter-feeding whales: this
one measured around 9m and they weigh around six to eight tons".
Jeff continued: "The throat pleats extended from its mouth all the
way down its body to about half its length. When they feed, the
whales take in a massive mouthful of water and the pleats allow the
throat to expand until the water is forced out between the baleen
plates that hang down from the top jaw, filtering out the small
fish, krill or squid. ”
"We weren't able to see the top of the head so couldn't confirm that
it had been injured there, but from the description we were given
when it was floating, it sounds likely that the cause of death was
from collision with a ship or injury from a propeller", said Jan
Loveridge, Strandings Network coordinator." You'd expect a whale to
avoid an oncoming ship, but apparently they have been known to be
oblivious to them when resting or feeding. Most fatal ship strikes
are apparently caused by ships travelling at speeds over 14 knots",
Jan explained, "and, although whale species with a highly visible
blow might be avoided by vessels in daylight, they can be very hard
to see at night. That's especially true for the minke, which only
has a small blow of about 3m in height, so they're difficult to see
even in calm weather".
Rory Goodall, a CWT volunteer and founder of Elemental Tours says
"We were particularly sad to see this one after having seen two
minkes feeding off Land's End a few weeks back on a trip to sea with
a friend,. As Rory describes, " We've seen more minke whales this
summer on our boat trips than ever before, even though we've been at
sea less due to adverse weather. Looking at our records and those of
Seawatch-SW, who've kept a dawn to dusk watch at Gwennap Head, near
Land’s End throughout the summer, the maximum number of sightings
coincided with high temperatures and unusually large numbers of
basking sharks in the area from late August to mid September. In
places, the sea was teeming with bait fish, “breezing” the surface,
being chased by larger predators beneath them, all feeding on a late
plankton bloom. This kick-started the food-chain into top gear,
attracting not only the minke whales but bottlenose dolphins,
harbour porpoises and even more unusually, pods of Risso’s dolphins.
Unfortunately, this wildlife frenzy occurred in some of the busiest
shipping lanes in the world and the more cetaceans attracted to the
area, the more likelihood of a ship strike."
It’s been fantastic to see all this and some of our younger
passengers were thrilled to be confronted by these fascinating
creatures. Their Mum said they realized how lucky they were to see a
minke whale and it was an opportunity of a lifetime. Her son said
his legs were shaking with excitement when he saw the whale and
still shake now when he thinks about it!"
The minke whale is found throughout the world's oceans, from the
Arctic to the Antarctic and is the whale most likely to be seen from
the shore in the UK. Minke whales were originally ignored by whalers
due to their small size, but as larger whales became rarer due to
over-exploitation and other threats, they became more economically
attractive. They are still commercially hunted in the North Atlantic
and this represents a major threat to the UK population.
"We're grateful to the members of the public and HM Coast Guard who
kept reporting the progress of the whale to us and its location when
it actually beached", said Jan Loveridge. "We're always pleased to
receive reports of stranded marine animals via our Hotline on 0845
201 2626. We'll be sending the report and photos of this one to the
Natural History Museum as usual, for inclusion in the national
database"
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