Stingray (various)

 

Class: Chondrichthyes
Order: Myliobatiformes
Family:    Dasyatidae
Size:    Width: Up to 7 feet (2.1 m) 
Weight: 1 to 750 pounds (0.45 to 340 kg) 
Diet: Molluscs, crustaceans, worms and fish 
Distribution: Tropical waters worldwide
Young:  2 to 9 live young per year 
Animal Predators:  Sharks 
IUCN Status: Several stingrays of the Dasyatidae family are listed: see Conservation below for details
Terms: Young: Pup
Lifespan: Unknown

 

Facts/Trivia:

·         There are over one hundred stingray species in the world.

·         Several stingray species have become major tourist attractions, in areas such as Stingray City in the Cayman Islands.

·         Some stingrays (like the Mangrove stingray) can jump out of the water while swimming.

 

Description

Stingrays have flat bodies. They are most closely related to sharksboth have cartilage rather than bone inside their bodies. Stingrays have large pectoral fins that look like wings, and when they use these fins to propel themselves through the water, they look as if they are flying. When stingrays stop swimming, they sink to the sea bed because unlike other fish, they do not have an air-filled bladder to help them stay afloat. Stingrays have a long, tapering tail, and growing from the tail is a barbed spine that contains venom. They have eyes on the top of their head and their mouth is located on the bottom. Females are usually larger than males. 

 

Habitat

Stingrays can be found in shallow temperate and tropical waters throughout the world, including oceans, seas, estuaries and rivers. They like to bury themselves under sand with only their eyes showing. 

 

Feeding Habits

Stingrays feed on crustaceans, fish, molluscs, worms and shrimp, crushing them with their teeth. They use their large fins to stir up the water bottom to bring shellfish out of their hiding places, then settle on the bottom, covered by sand, while eating. 

 

Reproduction

Female stingrays give birth to live young from eggs that developed inside their body. The larger the stingray, the more young they have at one time. The babies emerge tail first, with their wings rolled up. The wings unfold immediately, and the pups begin swimming right away.  

 

Behaviour

Stingrays are not aggressive and prefer to swim away when threatened, but they occasionally sting people as a reaction to being stepped on. When a rays spine comes in contact with another animal or person, the pain can last for months. It is recommended that people shuffle their feet while entering water in an area where stingrays are common. This warns stingrays that someone is coming and gives them the opportunity to move out of the way.

 

Conservation

The Niger freshwater stingray of Cameroon and Nigeria; the Mekong freshwater stingray, found in limited quantities in two Asian rivers (Mekong and Chao Phraya); the porcupine ray of the Indian and Pacific oceans; and the giant freshwater stingray of Australia and Indonesia are all listed as Vulnerable by the IUCN. A subpopulation of the giant freshwater stingray found in Thailand is listed as Critically Endangered. The Ganges stingray, found in the Ganges river in India; the pincushion ray of Africa; the white-edge freshwater whipray of Indonesia, Thailand and Malaysia and the marbled freshwater stingray of Thailand and Cambodia are all listed as Endangered. The blue-spotted ribbontail ray, found in the Indian and Pacific oceans is listed as Lower Risk, Near Threatened. The causes listed for their decline are massive habitat degradation as well as fishing pressure. 

 

Sources

http://animaldiversity.ummz.umich.edu/accounts/dasyatis/d._americana$narrative.html

http://library.thinkquest.org/C007974/2_1sti.htm

http://www.marinethemes.com/smoothray.html

http://www.wikipedia.com/wiki/Stingray

http://core.ecu.edu/biol/nortons/NCFishes/SharksSkatesRays/southern%20stingray/SouthernStingray.html

http://www.jeannieshouse.com/oceanarium/mantas/manta.html

http://mbgnet.mobot.org/salt/animals/stingray.htm

http://www.geocities.com/thetropics/6733/stingray.html

http://www.enchantedlearning.com/subjects/sharks/rays/

http://www.flmnh.ufl.edu/fish/Gallery/Descript/SouthernStingray/SouthernStingray.html

http://home.att.net/~travelwriter/caymanislands.htm