Bat ray
The bat ray is a striking member of the eagle ray family, known for its six-foot wide, diamond-shaped body and graceful swimming style that resembles a bat in flight. Primarily found along the California coast, but also inhabiting the Oregon coast and extending to Mexico, bat rays prefer shallow sandy bays and kelp beds, typically at depths of up to 150 feet (45 meters). Their bodies are characterized by large, wing-like pectoral fins and a long, whip-like tail equipped with venomous spines, which serve as a defense mechanism against predators. Adult bat rays can weigh between 20 pounds (9 kilograms) for males and up to 200 pounds (90 kilograms) for females.
These rays have a distinctive feeding technique, using streams of water to uncover prey such as clams, oysters, and crabs from the ocean floor. Bat rays are mostly solitary but can gather in large numbers during migration and mating seasons, where females typically give birth to 6 to 12 live young. Despite facing threats from humans and natural predators like sea lions and sharks, bat rays can live up to 23 years in the wild. Their unique characteristics and behaviors make them an intriguing subject of study within marine biology.
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Bat ray
The bat ray is a member of the marine family of eagle rays. Its six-foot wide, diamond-shaped body swims gracefully through coastal waters and skims the sandy bottom at depths of six fathoms, or 150 feet (45 meters).
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Rajiformes
Family: Myliobatidae
Genus: Myliobatis
Species: Californica
The bat ray is named for its swimming style and appearance. It looks similar to a bat in flight as it glides smoothly through the water on enlarged, wing-like, pectoral fins. It belongs to a family of rays known as eagle rays, partly because their heads resemble eagles' heads and partly because they swim as gracefully as eagles fly.
Bat rays are sometimes called California bat rays because they live mostly along the California coast, although they also live north along the Oregon coast and as far south as Mexico. The chief places to find these sea creatures is in shallow, sandy bays and coastlines where the water is up to 25 fathoms, or 150 feet (45 meters), deep. Kelp beds are also popular areas within their watery habitats. They glide with ease through the water and are even able to leap from the water and fly for short distances.
Adult bat rays grow to measure up to six feet (two meters) between the tips of their long, outstretched, blunt-tipped fins. A male may weigh between 20 and 30 pounds, (9 to 13 1/2 kilograms), while a female may weigh as much as 140 to 200 pounds (63 to 90 kilograms). From above, the bodies of bat rays are diamond-shaped and are wider than they are long. A long, whip-like tail with one or two venomous, or poisonous, spines serves as ready defense against any intruder or attacker. The spine itself can cause great injury, and the poison is strong enough to cause illness or death. Smooth, brown, olive, or black skin covers the topside of the bat ray, while the skin underneath is white. Like others in the family, its head and large eyes extend in front of its fins, whereas the fins of some species in other families of skates and rays surround the heads and eyes.
The bat ray uncovers its prey by cruising along the ocean floor and squirting streams of water from its mouth into the sand. It can blow a hole up to one foot (30 centimeters) deep. This technique exposes the clams, oysters, sea pens, sea snails, marine worms, and crabs that hide in the sand. The ray may also seize lobsters and fish above the sand's surface. Another technique that many skates and rays use is to fan the bottom with their fins and blow away the sand. Plates of hard teeth within its mouth enable it to crush the shells, eat the soft flesh, and then spit out the shells.
Bat rays live and feed by themselves most of the year, but small groups or even groups of thousands may gather in migrating and mating season. Heavier females have more young than those which weigh less. They typically produce between 6 and 12 live young. Each young ray weighs around one pound (1/2 kilogram) at birth and grows as it drinks milk from its mother. It already has its poisonous spine, which it can flip in any direction. As it grows older, it can only flip its spine in one direction, that is, over its back. Even so, the spine is an effective defense against intruders or attackers.
Fishermen occasionally catch bat rays and discover that the rays can fight wildly. Most captured rays are released into the ocean. Aside from being fished by humans, other threats to the bat rays include California sea lions, great white sharks, and broadnose sevengill sharks.
The bat ray is one of five species of skates and rays which swim around North America. There are about 20 species in this family, which is one of seven families of skates and rays.
The bat ray can live up to 23 years in the wild.
Bibliography
“Bat Ray Facts for Kids.” Kiddle, kids.kiddle.co/Bat‗ray. Accessed 30 Mar. 2024.
“Bat Ray.” Monterey Bay Aquarium, www.montereybayaquarium.org/animals/animals-a-to-z/bat-ray. Accessed 30 Mar. 2024.
Schmidt, Katie. “Myliobatis Californica (Bat Ray).” Animal Diversity Web, animaldiversity.org/accounts/Myliobatis‗californica/. Accessed 30 Mar. 2024.