Manta Birostris (latin) or giant oceanic Manta Ray is a ray in the family of the Mobulidae.
It is the largest known ray in the ocean and can grow up to 7 meters (23 ft) and can weight more then 1000 kg (2200 lb). Most Manta Rays have an average size of around 4 meters (12 ft).
Beside the giant Manta Ray, the reef Manta Ray is also encountered often at the Similan Islands. Manta Rays can speed up to around 25 km/h if they feel threaten by their natural predators such as the Great Hammerhead, Tiger and Bullshark as well as the Killer-whale.
Manta Rays are filter feeders and they consume mostly Zooplankton. They need to filter wast amounts of water to eat about 13% of their body weight per week.
Manta Rays often visit cleaning stations around coral reefs while cleaner fish free them from parasites.
Both species are listed as vulnerable by the International Union for Conservation of Nature (IUCN). The biggest threats to this fish as to most of the marine life are man made, pollution and fishing nets.
They are protected in international waters by the Convention on Migratory Species of Wild Animals (CMS), but are more vulnerable closer to shore.
Males become sexually mature when their width is about 4 m (13 ft), while females need to be about 5 m (16 ft) wide to breed.
When a female is becoming receptive, one or several males may swim along behind her in a "train". During copulation, one of these males grips the female's pectoral fin with his teeth and they continue to swim with their ventral surfaces in contact.
He inserts his claspers into her cloaca and these form a tube through which the sperm is pumped. The pair remains coupled together for several minutes before going their own ways.
It is Manta Season now!
The Team of Khao Lak Scuba Adventures