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WHAT IS ELASMODIVER? Not just Shark Pictures: Elasmodiver contains photos of sharks, skates, rays, and chimaera's from around the world. Elasmodiver began as a simple web based shark field guide to help divers find the best places to encounter the different species of sharks and rays that live in shallow water but it has slowly evolved into a much larger project containing information on all aspects of shark diving and shark photography. There are now more than 5000 shark pictures and sections on shark evolution, biology, and conservation. There is a large library of reviewed shark books, a constantly updated 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:
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SPINY DOGFISH |
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View all available Spiny Dogfish Pictures Spiny dogfish, Common spiny dogfish, Piked dogfish, Mud shark. Latin Name: Squalus acanthias Family: Squalidae Identification: Long, flattened, pointed snout. Grey to brown above usually with small white spots. White spots may follow lateral line. Eyes large. Mildly venomous spines on first and second dorsal fins. Anal fin absent. Belly white. Size: Maximum length 1.6 meters. size at birth 22-33 cm. Maximum recorded age 66 years. Habitat: Often cruise over sand and mud bottoms. Also frequently encountered over rocky reefs. From 0 to 900 meters. Inhabits estuarine, coastal and offshore waters sometimes migrating over great distances Newfoundland tagged individuals have been captured years later in Iceland. Normal migration patterns are usually more localized; Western Atlantic groups migrate between Canada and the US. Abundance and distribution: North and South Atlantic Ocean and South Pacific and Southern Ocean around Australia. Some populations may eventually be recognized as new species or distinct 'sub species'. An example of this is the recent resurrection of the North Pacific spiny dogfish Squalus suckleyi. The spiny dogfish's western range extends along the east coast of North America from Labrador to the Gulf of Mexico. Some populations are locally abundant while others have experienced steep declines leading to drastically reduced fishing quotas (especially in Europe). In the UK and Europe Spiny dogfish are the principal fish utilized in "fish and chips". They are also ground up to be used in fertilizers. Behavior: Cruises over soft bottoms either alone or in small groups. Occasionally schools (often segregated by sex) in response to food supply such as squid or salmon runs. May also form schools with other species such as leopard sharks and smoothhounds. Diet consists mainly of bony fishes. Other foods include octopus, squid and crustaceans. Reproduction: Ovoviviparous. Litter size from 1- 20. Spiny dogfish have a slow maturity rate (around 12 years) which makes them very vulnerable to over fishing. They also have the longest gestation period of any known vertibrate 18-24 months. Observations: Photographs: Similar species: The virtually identical North Pacific Spiny Dogfish Squalus suckleyi does not occur in the same areas as the spiny dogfish. The Smooth Dogfish or dusky smoothhound mustelus canis which has a sympatric range from the Bay of Fundy to the Gulf of Florida and from Southern Brazil to Argentina is easily recognizable as it lacks fin spines. Reaction to divers: These are curious and harmless sharks that will often closely approach divers and on occasion accompany them on their dives. If divers are buzzed by a dogfish they can often be recalled by tapping two stones together. The dogfish seem to find this irresistible and will repeatedly return to satisfy their curiosity. If engaging in dogfish feeds it is possible to play tug of war with these little sharks. Care should be taken to avoid their mildly venomous spines. Diving logistics: Spiny dogfish are sometimes attracted to inshore shark feeds organized in New England. As spiny dogfish schools are reported to reach plague like proportions in some areas, it may be possible to easily attract quite large numbers although the appearance of the schools is hard to predict. If planning to chum, try the summer months when the Gulf Stream has moved in towards shore. Other diving locations submitted by readers: Read about the spiny dogfish debate References:
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