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Saturday, May 7, 2011

Skate and Variant Skates Fish Atlantic Ocean

Skates Fish are closely related to sharks and rays. Skates Fish can be found in shallow bays to deep‐sea habitats and live on the bottom of the sea floor. Skates Fish have a huge pair of pectoral fins that connect the head to their body. The rounded shapes of the fins help form their flattened disk‐like body, with eyes on top and mouth underneath. The flat body and large fins give skates the appearance of flying when swimming through the water. They have small thin tail with 1‐2 fins on the tip that helps the skate steer, plus they can locate prey with electric organs found in their tail. The skate fish eats a variety of crustaceans, mussels, clams, snails, and worms. One of the best‐known species is the little skate, which can be found along the New Jersey coast in the Atlantic Ocean. This skate is 1 to 2 feet (30 to 61 centimeters) long. A larger skate that lives along the New Jersey coast is the barn‐door skate.

Skate Fish

Skate Fish are oviparous, meaning egg layers. After a breeding season, female skates can store sperm to fertilize and secrete eggs continually throughout a 3‐ 4 month period. Females may lay a pair of eggs every three to five days and may produce between thirty to forty pairs of fertilized eggs. The eggs are encased in a tough, leathery protective egg case that is black, with four points. Long thin tendrils extend from each point to anchor the egg cases to seaweed, rocks, or sand. Inside the egg case is yolk, much like the yolk in a hen’s egg. A skate embryo utilizes the yolk as nourishment and develops inside the egg case.

Development is complete in about 12 weeks when the skate hatch outs, looking like a miniature adult. Often after the eggs hatch the empty eggs cases wash ashore and are known as “mermaids purses” to beachcombers.

Skates

Skates are bottom-dwelling, egg-laying fish that are related to sharks and stingrays. Five species are common to the Gulf of Maine. All are both scavengers and carnivores that feed on a variety of organisms such as crustaceans, mollusks, worms and fish. Skates reach sexual maturity at a late age, have few offspring, and are relatively long lived. In addition, egg gestation rates can range from nine months up to six years. These characteristics, coupled with fisheries that select for the removal of large individuals, make skates highly susceptible to over fishing.

Thorny Skate (Amblyraja radiata)

• AKA: Starry Skate, Mud Skate
• Depth range: 25 to 75+ fathoms, most common in waters 50 fathoms or deeper.
• Max size: 41 in. (103cm) long, 25 lb.
• Color: Dark brown to grayish body surface, which may contain irregular dark spots.
• Conspicuous spines that resemble rose thorns, found on midline of back and tail.

Winter Skate (Leucoraja ocellata)

• AKA: Big Skate, Spotted Skate, Eyed Skate
• Depth range: shoal to 60 fathoms, most common in 25-35 fathoms.
• Max size: 43 in. (108cm) long, 15 lb.
• Color: Light brown body surface covered with small dark spots.
• Small spines cover majority of dorsal surface.
• Juveniles (less than 12 in. long) look very similar to the little skate and the two are often indistinguishable from one another.
• Males less than 22 in. long have small and inconspicuous claspers.
• Females less than 22 in. long lack small, rough patches of spines around the cloacal vent.

Skate

Little Skate (Leucoraja erinacea)

• AKA: Summer Skate, Common Skate
• Depth range: shoal to 75 fathoms, most common in 25-50 fathoms.
• Max size: 22 in. (55cm) long, 4 lb.
• Color: Light brown dorsal surface covered with small dark spots. Small spines cover majority of body surface.
• Males 14-22 in. long have large conspicuous claspers.
• Females 14-22 in. long have rough patches of spines surrounding the cloacal vent.

Smooth Skate (Malacoraja senta)

• AKA: Prickly Skate, Smooth Tailed Skate
• Depth range: 25 to 75+ fathoms, most common in waters 50 fathoms or deeper.
• Max size: 26 in. (64cm) long, 2.5 lb.
• Color: Pale brown, may have small dark spots on dorsal body surface.
• Wings lack hard spines.
• Pointed snout

Barndoor Skate (Dipturus laevis)

• Depth range: shoal to 100 fathoms, most common in 25-50 fathoms.
• Max size: 60 in. (152cm) long, 40 lb.
• Color: Brownish (may have reddish hue), with small dark spots covering dorsal body surface, distinct ventral gray coloration.
• Wings lack hard spines.
• Very pointed snout.

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