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Photo copyright Bill Mashek
Aetobatus narinari, Spotted Eagle Ray
Taken in the Galapagos Islands
Spotted Eagle Rays are second only to Mantas in size, reaching a width of over 2 m. They are stingrays with venomous barbs near the base of the tail which can deliver a fatal sting.
The name Aetobatus is derived from the Greek aetos meaning "eagle" and batis meaning "ray". The eagle part comes from the ray's beak-like nose. The A. Narinari species refers to several forms of Eagle Ray across the world. In fact, the name actually might refer to four different species, a so-called "species-complex". Molecular research is presently underway to help resolve the matter.
The pregnancy of the female Eagle Ray lasts a year. Up to four pups are then born fully developed and measuring 17-35 cm across.
Young Eagle Rays are kept in nurseries: a place where the mother gives birth and the babies and juveniles spend the first part of their lives. It's thought that nursery grounds provide the young a better source of food and protection against predation
The Eagle Ray lives on seagrass flats and sandy areas of coral reefs. Its disc is diamond-shaped and is wider than it is long. The tail is long and slender.
Eagle Rays are more often seen actively swimming than are the other rays. They are often encountered near the surface and sometimes even jump out of the water. They are, however, also found down to 60 m. Normally they are solitary but, as in the photo, they may be seen in large groups.
The low reproduction rate of just four or less offspring a year, the ray's inshore habitat and thus susceptability to a variety of inshore fishing gear, has lead to it being classed as Near Threatened and Vulnerable on the IUCN Red List.
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