How to Identify Basking Shark

To identify Basking Shark (Cetorhinus maximus), look at these key features.

Physical Characteristics

Body shape

torpedo

Coloration

Typically dark grey to blackish-brown on the dorsal surface, often with lighter mottling, and a paler, sometimes whitish, ventral surface. The coloration can vary slightly depending on geographic location and individual.

Scale type

placoid

Mouth position

terminal

Distinctive features

Enormous, cavernous mouth that extends almost the entire width of the head, capable of opening up to 1 meter wide., Five very long gill slits that almost encircle the head, meeting dorsally and ventrally., Prominent, conical snout., Small, numerous, recurved teeth (non-functional for feeding)., Large, crescent-shaped caudal fin., Rough skin covered in placoid scales (dermal denticles).

Dorsal fin

Two distinct dorsal fins. The first dorsal fin is large, triangular, and erect, positioned about midway along the back. The second dorsal fin is significantly smaller.

Tail fin

Large, powerful, and crescent-shaped (lunate), with the upper lobe slightly larger than the lower lobe.

Pectoral fin

Large and triangular, positioned just behind the gill slits.

Distinctive fins

Anal fin is present and small. Pelvic fins are also present and relatively small.

Identification Tips

1. 1

   Size

   Second largest fish in the world, reaching lengths of up to 12 meters (40 feet), though average adults are 6-8 meters (20-26 feet).

2. 2

   Mouth

   Enormous, gaping mouth that is held wide open while feeding, almost reaching the eyes. This is the most distinctive feature.

3. 3

   Gill Slits

   Five very long gill slits that nearly encircle the head, meeting above and below the throat.

4. 4

   Snout

   Conical and pointed snout.

5. 5

   Behavior

   Often seen 'basking' at the surface, slowly swimming with its mouth open, filtering plankton. Its large dorsal fin and upper caudal fin lobe are often visible above the water.

Explore Basking Shark