I was a bit surprised when I caught a baby sevengill shark in Port Phillip Bay. The Bay is known for gummy shark, so at first that’s what I assumed this was. But after reviewing the photos, and a few comments on our Facebook page, it’s pretty clear that it was a sevengill.
There are only two types of sharks with seven gills – the bluntnose and the sharpnose. This was a baby bluntnose sevengill. Most other shark species have five gills.
The bluntnose sevengill shark is one of the only sharks in the cowshark family (Hexanchidae) that prefers shallow coastal waters. As well as being known as the bluntnose sevengill shark, it is also known as the spotted cow shark, mud shark, and the Tasmanian tiger shark.
They are a large shark that grows up to 3m (about 10 feet) in length and up to 110kg (240lbs). It has a blunt snout with a broad head, large body, one dorsal fin far back in its body, a large anal fin, and small black and white spots covering its back and fins. Its lower jaw has six rows of comb-shaped large teeth and five rows of saw-like teeth on the top jaw.
These sharks are considered fairly aggressive. They are known to hunt in packs for large prey, and their diets are known to consist of approximately 30% mammals (dolphins and seals). They have large mouths for eating large prey, and eat other sharks as well as their own kind, rays and bony fish.
Needless to say, I threw this baby back to get nice and big.