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 A
very rare Ribbonfish, also know as Oarfish,
Regalecus glesne,
was found washed up on the coast near Hauxley in Northumberland
in February. They can grow up to 10 metres long and weigh more
than a quarter of a tonne and are usually more at home in deeper
sub-tropical seas. It is a very rare fish in UK waters, only 3
or 4 have been caught or washed up in the last 50 years. The
Ribbonfish propels itself with a long undulating dorsal fin and
is the longest bony fish in the sea, and this mode of swimming
may suggest a sea serpent and it is believed that it was feared
by mariners for many centuries as a mythical sea serpent or
monster.
 The
Moray Eel is quite a scary looking fish with its large pulsing
mouth and vacant stare, but there is more, for behind the large
fish’s toothy mouth looms a second set of jaws, which launch
from the throat, grab prey from the front teeth, then retreat
into the dark tunnel of the eels oesophagus. It’s the stuff of
science fiction, but it is a brilliant feeding mechanism for
such an elongated creature.
Unlike most bony fish, morays don’t seem to
generate enough suction to help in swallowing, instead it has
this novel dual-jaw arrangement. which allows the animal to both
restrain and transport big prey –the most efficient nourishment
for big animals-down the long throat. This is the only
vertebrate known to have such a feeding mechanism, but on a
different branch of the evolutionary tree, some snakes have a
related system, a set of ratcheting jaws that grip and manoeuvre
food into the gullet. This is a wonderful example of
convergence, when distant organisms facing the same problem
develop similar solutions.
Fish farmers off the coast of Norway are being
plagued by a tiny but very costly
sea creature that is fouling the nets which surround the farmed
salmon. The tiny hydroids,
Ectopleura larynx,
settle on the mesh of the nets looking like a
forest of thin white threads that appear to end in a pink
pinhead. These tiny creatures have shown that if the nets are
not cleaned often enough they can cause serious problems. In the
course of just a few weeks they can form carpets that almost
choke the meshes and thus lower the water quality for the farmed
fish. Scientists studying the recent increase in net fouling are
considering various possible explanations, such as composition
of the fish feed, or the type of coating used on the nets or
even net colour.
There were 9 reported sightings of Bottlenose
Dolphins during March, 8 of the north coast pod between Trenow
Cove near Marazion and St Ives, and one of the south coast pod
in the Carrick Roads, Falmouth.
Four of five reports of Harbour Porpoises
were off Porthgwarra and the other report was of 4 animals off
Trewavas Head. A pair of unidentified dolphins were seen off
Logan Rock on the 30th and off Porthgwarra on the 31st. Two Grey
Seals were seen ½ mile off Kenidjack Castle on the 15th and also
that day, an Octopus was seen by divers on the wreck of the Juan
Ferrar, off Boscawen
Point.
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