Bull huss vs dogfish: how to tell them apart

The names cause some of the confusion

“Bull huss”, “nursehound”, “greater-spotted dogfish” and “large-spotted catshark” refer to Scyliorhinus stellaris. “Lesser-spotted dogfish” and “small-spotted catshark” refer to Scyliorhinus canicula. Common names vary, so a scientific name is useful when checking an identification.

Spot pattern

Bull huss tend to show larger, bolder and more widely spaced dark spots, sometimes mixed with pale spots. Lesser-spotted dogfish usually carry many smaller dark spots over a paler grey-brown body. Pattern is useful, but photographs, lighting and individual variation mean it should not be the only feature.

Nasal flaps and mouth

Look underneath the snout. On a lesser-spotted dogfish, the nasal flaps extend towards and connect around the mouth area. On a bull huss, the nasal flaps stop short and remain more clearly separated from the mouth. A clear underside photograph is therefore more useful than another distant side view.

Size and build

Bull huss can grow substantially larger and look heavier through the head and front of the body. Lesser-spotted dogfish are generally smaller and more slender. Size supports an identification but does not prove it—a juvenile bull huss can overlap with a larger dogfish.

Habitat can support, not decide, the ID

Bull huss are associated particularly with rocky ground, algae and crevices, while small-spotted catsharks also occur on sand and mud as well as rocky areas. Where the fish was caught is context, not a substitute for physical features.

How to photograph the fish for identification

• Take one full side-on image showing the overall spot pattern and body proportions.
• Take one clear underside image of the snout, nasal flaps and mouth.
• Keep the fish supported and minimise time out of water.
• Do not rely on colour, one spot or estimated size alone.

Sources and uncertainty

Check the Wildlife Trusts nursehound guide, its small-spotted catshark guide, and the MarLIN small-spotted catshark description. Castwise Fish ID can suggest an answer and alternatives, but it is not a legal or biological determination.

Sources and further checks

Conditions and rules change. Before a session, use the Met Office coast and sea forecast, check RNLI angling safety advice, and verify retention rules in the current UK MCRS table plus the authority for the water you fish. Sources reviewed 15 July 2026; see the Castwise editorial policy.