Manta Rays: Feeding strategies
Manta Rays: Feeding strategies
Manta rays, or mobulid rays, are classified as the world's biggest rays, with Reef mantas (Mobula alfredi) growing as big as 4m wide and Oceanic mantas (Mobula birostris) as large as 7m wide. For an animal that big, you can be sure they spend a lot of time thinking about food! If you're planning a trip to the Maldives, especially to InterContinental's Maamunagau lagoon, you're bound to run into these gentle giants munching away on their favourite foods. So here is everything you need to know about Manta ray feeding habits!
Mobulid rays feed on Plankton, or very small shrimp, krill, arrow worms, and jellyfish. To maximize their food intake, they have cultivated a variety of feeding strategies.
The manta swims through the water with its massive mouth wide open and its spoon-like cephalic fins unfurled to scoop plankton-rich water through its gills. This is known as straight feeding, but we often see many variations of it in the rays' swimming positions and the strategies they use as a group. Here are some of the main ones:
01. Surface Feeding
Very often, especially after a rainy spell, Plankton gathers at the water's surface, attracting the mantas. Here, the manta will tilt its head back, so its mouth is just below the surface and swim horizontally forward with its cephalic fins open. After a few meters, it will dip down a few meters, do a 180-degree turn, and swim again in the opposite direction.
02. Somersault Feeding
Some mantas appear to learn how to do somersaults, or backflips, at depth while they feed. Although not all manta rays can do this, those who do will perform several 360-degree, tight, repeatedly turns before they eventually break the loop and go back to feeding normally.
03. Chain Feeding
In this case, we see several mantas coming together in a group. They line up horizontally, head to tail, and swim through the water column like they normally would. Similar to a flock of birds flying in a 'V' formation, they position themselves slightly above or below the individual in front of them.
04. Piggyback Feeding
When a larger manta is feeding, usually a female, some smaller males will come close to her and swim right on top of its back. They even time the movement of their pectoral fins to align with the bigger manta, looking as though they are piggybacking. On occasion, you can see up to 4 manta rays stacked this way, but their piggyback will break once the lowest manta turns to go back in the opposite direction. This method helps them feed on Plankton in different parts of the water column. This method has only ever been seen in Reef manta rays (Mobula alfredi).
05. Cyclone Feeding
By far the most impressive spectacle for snorkelers, cyclone feeding occurs in only a few areas of the world (most notably, Hanifaru Bay). Cyclone feeding is when a group of as many as 150 manta rays come together. They begin by chain feeding and slowly looping around until they form a large circle, and as more mantas join the feeding train, the loop grows across the water column to look like an underwater cyclone. Cyclones can be around 15 meters wide and last as long as 60 minutes!