Monday, July 28, 2014
   
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Sharks Of The Pacific Northwest

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Basking Shark During World War II, this species became a nuisance to British Columbia’s commercial nets. In 1953 BC newspapers reported stories of Barkley Sound basking sharks destroying the gillnets of many fishermen. In 1955 the BC Department of Fisheries installed a cutting blade on the bow of the regional fisheries patrol vessel, the Comox Post. When the vessel approached a school of basking sharks the knife edge would be lowered from a hinge by a cable so that the cutting edge was just below the surface of the water and sharks cruising on the surface would be sliced in half.
Blue Shark   This species prefers colder waters (7-16°C) but tolerates warmer water too (+21°C). Blue sharks normally active and fast swimmers at the surface and can be found down to a depth of approximately 610 m. Males and females live segregated. Aside from the Oceanic whitetip shark, and the Silky shark, this is probably the most abundant offshore species. Blue sharks seem to migrate clockwise with the Gulf Stream and some have been tagged in US waters only to be recaught in Spain. Others have been tagged in the Canary Islands and were recaught in Cuban waters.
Bluntnose Sixgill   This species lives preferably in deeper waters over the continental shelves and upper slopes, down to about 2000 m. Sluggish, but a strong swimmer, normally found close to the bottom but can ascend to the surface when feeding. Nocturnal, rests on bottom during daytime. Juveniles often found close inshore.
Broadnose Sevengill Shark   The sevengill is primarily a benthic shark found over the continental shelves down to depths of about 650 m, but has also been found in shallow waters. Larger sharks prefer deeper waters. The sevengill is a very active swimmer often cruising slowly near the bottom. This species apparently coordinates its movements in bays with tidal cycles, moving in with a tidal rise and out with its fall.
Brown Catshark   The brown catshark is believed to be a solitary nocturnal shark. Can be found at depths of up to 564 m. This is a slender shark with a long snout. Small dorsal fins located on the back half of the shark. The first dorsal fin is located over the pelvic fin. It has a short lower caudal lobe with a slightly longer upper caudal lobe. The terminal lobe is relatively wide. The shark has a long snout with large eyes with relatively small spiracles and five pairs of gill slits.
Brown Smoothhound This shark is an active and fast swimming species in coastal waters. The brown smoothhound can be found individually or in small schools. The shark can segregate by sex and size. It is generally found on continental shelves from o to 200m.
Filetail Catshark   Little is known about this shark. It is able to survive in low oxygen environments and is very difficult to find and study. Commonly lives between 91 and 1251m. This is a slender shark with a long snout. Small dorsal fins located on the back half of the shark. The first dorsal fin is located over the pelvic fin. It has a short lower caudal lobe with a slightly longer upper caudal lobe. The terminal lobe is relatively wide. The shark has a long snout with large eyes with relatively small spiracles and five pairs of gill slits.
Great White Shark   A huge and powerful shark, very active with a stiff (scombroid-like) mode of swimming. Due to its feeding behavior, white sharks are often found in the vicinity of seal populations (South Australia, South Africa, California). White sharks possess a higher body temperature due to a modified circulatory system that enables them to retain a body temperature warmer than the surrounding water (up to 10 to 15 °C higher). This offers a higher activity level due to an increase in muscle power.
Leopard Shark   This shark is an abundant species of cool and warm-temperate waters. Found inshore and offshore in continental littoral waters. It is most common on or near the bottom in shallow water, from about 4m down to 90 m. Prefers sandy or muddy bays. This is an active strong swimming species. They can be found individually or in small schools that seem to be nomadic. The swimming motion of this species is undulating. Can be seen together with Brown Smoothhound and Grey smoothhound or Spiny dogfish.
Longnose Catshark   There is little is known about this shark. It is able to survive in low oxygen environments and is very difficult to find and study. Commonly lives between 180 and 1881 m. This is a slender shark with a long snout. Small dorsal fins located on the back half of the shark. The first dorsal fin is located over the pelvic fin. It has a short lower caudal lobe with a slightly longer upper caudal lobe. The terminal lobe is relatively wide. The shark has a long snout with large eyes with relatively small spiracles and five pairs of gill slits.
Pacific Angleshark   This shark is slow and timid. It lays buried in the sand and strikes at prey rapidly. It is generally nocturnal and solitary. This shark has a ray like body. Strong dorso-ventrally flattened with a wide head and very wide pectoral and pelvic fins. No anal fin. Lower caudal lobe on the tail is larger than upper lobe. This shark has a wide mouth terminal with nasal barbs. The shark has 5 pairs of gill slits.
Pacific Sleepershark   This shark is an ambush predator and can capture faster prey. It has the ability to suction great a great deal of water in and suction in prey. This shark has a cylindrical body with no anal fin and short pectoral fins. It has low dorsal fins with the first dorsal slightly larger than the second. It has a moderately long upper caudal lobe to the tail fin. The snout is rounded with a mouth that appears almost straight in a ventral view. It also has 5 pairs of gill slits.
Prickly Shark   The sharks can be found as an individual or part of a group. Feeding mechanism is most likely suction to inhale prey. This shark has two dorsal fins that are close to the same size there is also no anal fin. The shark also has large broad pelvic fins. The upper lobe of the caudal fin is large while the lower lobe is short. It has large eyes, wide nostrils and small spiracles.
Salmon Shark   This shark is considered very common and lives in coastal and oceanic waters from the surface down to depth of approximately 668 m exhibiting a preference for boreal to cool water. They are able to maintain a higher body temperature (rete mirabile). This species can be solitary, found in schools or feeding aggregations.
Shortfin Mako   The shortfin mako is generally a nervous particularly fast species which prefer epipelagic and littoral waters from the surface down to at least 417 m. They have the tendency to follow warm water currents in their most northern and southern parts of their range during summer months. The mako is probably the fastest shark species of all. When caught often leaps several times out of the water.
Spiny Dogfish   A well studied species. This is probably the most abundant shark species of all. This shark lives preferably close to bottom. Active swimmer found over the continental and insular shelves and upper slopes down to approximately 1236 m. This species can tolerate brackish water and is often found in enclosed bays and estuaries. It can be found as an individual or in enormous groups.
Thresher Shark   This shark lives in coastal waters over the continental and insular shelves, and epipelagic. Found from the surface down to 366 m, with juveniles living in shallow waters. This shark is a very active and fast swimmer that can leap out of the water. This species and the other thresher sharks possess an elevated body temperature due to a special blood circulatory system (rete mirabile) that enables them to live in colder waters.
Tope Shark   This shark is an active and fast swimming species of coastal waters that can be found in pelagic waters but not oceanic. Prefers depths from the surface down to about 598 m. It is often found in small schools that are highly migratory. Males and females live segregated except during mating season. Juveniles are born in shallow water. This species is sometimes called the “Soupfin shark.”

Northwest Shark Preservation Society

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Measuring a Small Seven Gill SharkThe mission of the Northwest Shark Preservation Society is to use current research techniques to study various shark species and the interactions they have with their environment; to educate and enlist society in the protection of sharks thereby aiding in the protection of aquatic ecosystems; and to pioneer relationships between the scientific community and the general public.

Why Conserve Sharks?

Sharks have inhabited the world’s oceans for over 400 million years. But humanity, with our short sighted environmental policies, have put many species at risk, and driven others to extinction. NOAA has estimated that the North American Coastal Shark Population has decreased 90%.*** It is estimated that 70 – 100 million sharks are killed every year as a result of bycatch and for the vast international demand for shark fins for soup. This popular delicacy requires that sharks be finned. The most common form of fining involves bring the shark aboard ship, cutting the fins off and throwing the still living shark back into the water. The shark, now unable to swim, slowly sinks and drowns because it cannot generate the forward movement that allows it to breath.

Our Research Boat

A recent report on sharks in the northwest Atlantic reveals that populations of some large species have fallen by 75% to 90% since 1986. Research indicates that some formally high population species are now present at less than 2% of their original numbers. Pacific shark populations have fallen with similar percentages.

As apex predators, sharks maintain a balance within the marine ecosystem and they play a critical role in our oceans. Their disappearance could have devastating effects throughout the marine environment. For example, populations of marine mammals, fish and crustaceans could experience rapid population growth. This would cause a cascading like effect that could damage the entire marine ecosystem. Our goal then is to help stop the slaughter of all shark species and help reverse the effects of over fishing, bycatch loss and recreational fishing pressures throughout the Pacific Northwest.

***Jackson, J.,  “Historical over fishing and recent collapse of coastal ecosystems.”  Science, DOI:10.1126/Science (2001), pg 293,629.

 

Get Involved

There are many ways that you can become involved with our mission. One way is to Contact Us to help in some fashion. We need help with business functions, fund raising and educational activities. Please Contact Us if you are interested.  You can also follow us on Facebook and twitter and finally, a donation to our cause is always appreciated. A cash donation has its rewards too. You can view the rewards at our donation center.

Send A Kid to Camp

We are working to raise capital for our newest project involving a science camp high school students. This summer our education department will take our outreach to the next level. We will be providing an all-expense-paid week-long trip to the coast for select high school students. Check out our funding page.

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