"Animals"

"BISON"

Close-Up of a Bison

With their large, sharp horns, bison are formidable foes. During mating season, bulls fight for the right to breed with harems of cows, but rarely duel to the death.

Bison and Her Calf
Bison cows give birth after nine months and nurse their calves for about a year. Calves are able to stand shortly after birth, but remain vulnerable to wolves and bears until they reach maturity at the age of about three years.

Two Male Bison Fighting
Two male bison spar in a field. Males battle for mating primacy, but such contests rarely turn dangerous.

Herd of Bison
Conservation programs at parks and zoos have combined forces with farmers, working to increase bison populations. Today there are about 200,000 bison in ranches and reserves.

"SEA TURTLES"

GREEN SEA TURTLES
Green sea turtles are reptiles whose ancestors evolved on land and took to the sea to live about 150 million years ago. They are one of the few species so ancient that they watched the dinosaurs evolve and become extinct.

Flatback Turtle
Flatback turtles, such as this one in the Melbourne Aquarium, are native to Australia. Their carapaces can reach up to 39 inches (99 centimeters) long.

Leatherback Turtle Laying Eggs
Leatherback sea turtles lay their eggs in nests on shore, where they are vulnerable to scavenging dogs and beach-strolling humans.

Newly Hatched Leatherback Sea Turtle..Leatherback hatchlings make a perilous journey from their nest to the ocean, and are not even safe once they make it. Few survive to adulthood.

Female Leatherback at Surf's Edge..A female leatherback sea turtle heaves herself from the surf at night to nest. Females often return to the same nesting areas where they were born to produce their own offspring.

Kemp's Ridley Sea Turtle Hatchlings..Unlike other sea turtles, female Kemp's ridley turtles come ashore to lay their eggs in the daylight hours.

Olive Ridley Sea Turtle..Olive ridleys get their name from the coloring of their heart-shaped shell, which starts out grey but becomes olive green once the turtles are adults. They have one to two visible claws on each of their paddle-like flippers.

Loggerhead Turtle...Loggerhead turtles are the most abundant of all the marine turtle species in U.S. waters. But persistent population declines due to pollution, shrimp trawling, and development in their nesting areas, among other factors, have kept this wide-ranging seagoer on the threatened species list since 1978.