Day Eight: The Galapagos Shark

Statistics

• Can grow to 12 feet in length
• Can weigh as much as 200 pounds
• Found off tropic oceanic islands
• Lifespan is at least 24 years

According to the International Shark Attack File, the Galapagos shark has been responsible for one fatal attack on a swimmer in the Virgin Islands. Inquisitive and persistent, the Galapagos shark is regarded as dangerous to humans and diving unprotected is not advisable in areas where they are abundant. They are known to approach close to swimmers, showing interest in swim fins or hands, and are drawn in large numbers by fishing activities.

Feeding

This shark feeds primarily on bottom-dwelling fishes as well as on squid and octopus. These fish include eels, flatheads, groupers, flatfish, and triggerfish. The Galapagos shark displays threat gestures to warn competitors in the search for food. Large sharks are potential predators of the Galapagos shark. Cannibalism is also reported within this species.

Reproduction

Galapagos sharks are "viviparous", or livebearing, with embryos nourished by a yolksac-placenta during gestation. Mating and birth occurs early in the year within Hawaiian waters. Female individuals often have mating scars from males biting the gills, fins, and body. After gestation during which the embryos develop inside the mother, live birth results in a litter size of 4-16 pups. Each pup measures 24-31 inches in length. The pups stay in shallow water nursery areas to avoid predation and cannibalism from members of their own species, eventually moving out to deeper waters as they mature. Males mature at 7-8 feet long and 6–8 years old, while females mature at 7½-8½ feet long and 7–9 years old. Neither sex is thought to reproduce until 10 years of age.

These sharks are very beautiful. Here’s a video of one up close.

Sources

http://en.wikipedia.org/wiki/Galapagos_shark
http://www.flmnh.ufl.edu/fish/Gallery/Descript/galapagosshark/galapagosshark.html