Species Spotlight: Oceanic Manta Rays vs Spine-Tailed Devil Rays

Current knowledge of oceanic manta rays in New Zealand is very limited. These impressive rays are often confused with spine-tailed devil rays. We’ve written this species spotlight in conjunction with Manta Watch New Zealand, to raise awareness of their research about these majestic creatures.

1. Size – Adult oceanic manta rays weigh up to 2,000kg whereas the spine-tailed devil rays reach about 300kg in weight.

2. Length – A fully grown oceanic manta ray’s wingspan can reach up to 7m whilst spine-tailed devil rays reach to about 2m.

3. Appearance – Besides their difference in size, there are some differences in appearance which can help us tell the two apart.

4. Stingers – Whilst both are closely related to stingrays, the oceanic manta ray does not have a stinger at the end of its tail whereas the spine-tailed devil ray does. However, they are generally harmless.

5. Range – The spine-tailed devil ray is found worldwide in tropical to warm, temperate waters. In New Zealand, they are usually found in waters deeper than 200m in the open ocean. The oceanic manta rays are generally found along the continental shelf in water temperatures of 18°C or more.  

6. Population Size – Global population size estimates for both species are lacking as well as population size estimates for New Zealand. Analysis of collection records and sightings data suggest that spine-tailed devil rays are more abundant than oceanic manta rays in New Zealand.

7. Diet – Both oceanic manta rays and spine-tailed devil rays feed on plankton such as krill, copepods and crustacean larvae. Depending on the concentration of food, these rays may feed in a straight line or barrel roll (somersault) through the water column.

8. Behaviour – Oceanic manta rays are generally solitary (besides for courtship, mating and aggregating at feeding sites or cleaning stations). You are more likely to see spine-tailed devil rays in groups.

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