Not just Shark
Pictures: Elasmodiver contains photos of sharks, skates, rays, and
chimaera's from around the world. It began as a simple web based
field guide to help divers find the best places to encounter
different species of sharks and rays but it has slowly evolved into
a much larger project containing information on all aspects of shark
diving and photography. There are now more than a thousand shark
pictures and sections on shark evolution, biology, and
conservation. There is a large library of reviewed shark books, a
constantly outdated shark taxonomy page, a monster list of shark
links, and deeper in the site there are numerous articles and
stories about shark encounters. Elasmodiver is now so difficult to
check for updates, that new information and pictures are listed on
an Elasmodiver Updates Page that can be accessed here:
If you're looking
for a broader range of marine life pictures the following links
represent a new area of elasmodiver.com that contains pictures of
other marine organisms and of marine habitats. This expansion of
Elasmodiver is in its first stages but will eventually include pages
on all types of marine mammals, bony fishes and marine invertebrates
as well as coastal habitats, reefscapes and other imagess relating
to the ocean. Please return regularly to enjoy the progress.
Identification: Highly
flattened body. Long pointed snout. Leading edges of pectoral fins are concave
near tip of snout, convex around head and have a second more defined concavity
behind head before extending outward to free tips. Trailing edge of pectorals
broadly rounded. Pelvic fins distinct. Row of spines above each eye and from
lower back along tail. Dorsum shades of brown with subtle dark and/or pale spots.
Dark patch on snout is not always obvious. Prominent dark circle (ocelli) on each pectoral fin with light centers. Ventrum pale. Eyes
proportionately larger than big skate.
Size: Maximum
length 120cm but usually from 60 to 90cm.
Habitat: Sometimes
seen on low lying kelp (broadleaf kelp) but generally found ongently
sloping sand and mud bottoms usually below 20 meters to 600 meters. Inhabits coastal areas, estuaries, bays and continental
shelves.
Abundance and distribution: Once
frequently encountered in British Columbia and Washington, Longnose skates are
now uncommon from Alaska to Southern California.
Behavior: Usually
seen lying motionless on substrate or under sand with eyes protruding but occasionally seen actively foraging
over soft bottoms. May occasionally enter shallows in search of food.
Reproduction: Oviparous.
Lays flattened egg capsule with hooked extensions on corners.
Photographs:
Deep Cove, Vancouver Island.
Similar species:
Big
skate - Raja binoculata distinguished by more kite shaped body and dark centers
of occeli, California skate - Raja inornata, and
Starry skate - Raja
stellulatawhich has a blunter snout and more intricate markings.
Reaction to divers: Very
docile. Remains motionless unless molested. Try not to hover directly above the
body as this may cause it to bolt.
Diving logistics:
Rarely seen at a few locations along the North Pacific coastline. The photograph
above was taken in November at Deep Cove, Vancouver Island in110ft of water on
gently sloping silt far from any walls or reef structure. Anyone finding a Longnose skate whilst diving is encouraged to
contact me in order to built an information base of sightings. Useful
information would include depth, time of year, and bottom composition.
Other diving locations:
References:
Coastal Fish Identification, California to Alaska. - Paul Humann - New World
Publications.
Pacific
Fishes of Canada - J.L.Hart. Fisheries Research board of Canada. Ottawa
1973.
Coastal
Fishes of the Pacific North West - Andy Lamb and Phil Edgell - Harbour
Publishing
