Photo Identification Guide: Gill Rakers of Manta ... - Manta Trust

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Photo Identification Guide: Gill Rakers of Manta & Mobula Rays. Manta and mobula rays are all large filter feeding fishes which use their modified gill rakers to ...

Photo Identification Guide: Gill Rakers of Manta & Mobula Rays Manta and mobula rays are all large filter feeding fishes which use their modified gill rakers to filter planktonic food from the water column. Each individual has five pairs of gill slits, each of which is encircled by a ring of feathery gill filaments known as ‘rakers’. The gill rakers of manta and mobula rays are increasingly being used in Chinese medicine. As a result, there is an increasing demand for these feathery gill filaments in Asia, driving a global fishery for these increasingly threatened species. When the rakers are removed from the dead animals (usually Above: Gill Rakers for Sale in China Above Right: Gill Raker Soup – Peng Yu Sai at the fish markets) they are cut in half, before being dried and then shipped to the point of sale.

Gill Rakers Drying in Sri Lanka

This guide has been created to aid the identification of the each species’ gill rakers in order to help scientists and conservationists working in the field to better understand and monitor the trade in these animals.

Gill Rakers inside the mouth of a Spine-tail Mobula Ray (Mobula japanica)

Gill Rakers Being Removed From an Oceanic Manta Ray (Manta birostris)

Species

Whole Animal

Gill Raker Close-up

Dry Raker

Oceanic Manta Ray Manta birostris

Chinese Trade Name: Flower Gill

Sickle-fin Devil Ray Mobula tarapacana

Species

Spine-tail Devil Ray Mobula japanica

Bent-fin Devil Ray Mobula thurstoni

Whole Animal

Gill Raker Close-up

Dry Raker

Species

Whole Animal

Close-up

Dry Raker

Short-fin Pygmy Devil Ray Mobula kuhlii

Image Needed

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Whale Shark Rhincodon typus

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Guide Created by: Guy Stevens, Director – Manta Trust [email protected] / www.mantatrust.org Image Copyright: Guy Stevens, Paul Hilton, Thomas Peschak, Daniel Fernando & Gisela Kaufmann Thanks: Dr. Mahmood Shivji - Professor Director, Guy Harvey Research Institute for DNA analysis of the gill raker samples & The Manta Ray of Hope Project for supplying market research data and Images.