About Spotted Ratfish
Spotted ratfish (Hydrolagus colliei) are not related to rats, and they're not eels, and they're not a type of shark — though they're in the same class (Chondrichthyes, the cartilaginous fishes). They are chimaeras: a separate subclass (Holocephali) that diverged from the shark and ray lineage over 400 million years ago, before the first trees existed on land. They have fused tooth plates instead of individual teeth, a single opercular flap over the gills instead of multiple individual slits, and smooth iridescent skin instead of denticle-covered hide.
They're found throughout California coastal waters at 100 to 3,000 feet, with most recreational encounters at 100 to 500 feet over soft bottom. FishBase documents the maximum at 100 cm (about 40 inches). California catches typically run much smaller — 1 to 4 lbs is typical bycatch size.
Nobody targets ratfish. They come up on deep-drop rockfish or hake rigs and surprise the angler who pulls them to the surface and finds something they weren't expecting. The reaction is usually a double-take. That's fair — they look extraordinary.
How to Catch
Ratfish find your bait. They're benthic feeders on soft bottoms, using the lateral line system and electroreception to locate worms, clams, and small invertebrates. A baited dropper rig at 150–400 ft over sandy or muddy bottom will pick up ratfish if they're present. The bite is typically a slow, heavy pull — not the sharp bounce of a rockfish bite.
When you get one to the surface:
- Identify the dorsal spine immediately. It's the first spine on the first dorsal fin — typically 3–4 inches long, positioned prominently at the front of the fish. It's mildly venomous.
- Grip behind the head with a gloved hand or towel, avoiding the dorsal area.
- Use long-nose pliers to remove the hook.
- Release or keep — your choice. The fish doesn't get easier to handle over time.
Do not try to hold the fish by the tail — the elongated tail isn't structural for gripping.
Eating Profile
Edible, rarely kept. The flesh is white, mild, and lean — similar to other deep-water white-fleshed fish. Most California anglers release ratfish because they look alien and the fillet yield is modest. If you do keep one, dispatch quickly, ice immediately, fillet like a round fish (ignore the cartilaginous skeleton — it fillets the same as bony fish). Avoid the liver, which is not palatable. Pan-sear or bake; don't overthink it.
Common Mistakes
- Grabbing the fish without looking first. The venomous dorsal spine is the first thing you need to locate before your hands go anywhere near the fish. Don't reach for it without looking.
- Expecting it to fight like a rockfish. Ratfish are slow, deep-water animals. The fight is heavy with current resistance but not dramatic. They don't sprint or run.
- Assuming it's a shark. The body shape causes occasional confusion — it's cartilaginous, pointed tail, smooth skin. But the rabbit-like face, fused tooth plates, enormous eyes, and smooth opercular flap identify it immediately as a chimaera.
- Not having pliers ready. Always have pliers at hand on a deep-drop trip. If you're not prepared for hook removal without bare-hand contact, a ratfish encounter becomes awkward fast.
Month-by-Month
- Jan–May: Present year-round at depth; less commonly encountered as fewer anglers run deep-drop trips in winter.
- Jun–Jul: Deep-drop season picks up. Ratfish encounters increase with fishing pressure at 150–400 ft.
- Aug–Sep: Peak encounter season; most deep-water trips cover soft-bottom areas where ratfish occur.
- Oct–Nov: Still producing on deep-water rockfish trips; weather increasingly limits access.
- Dec: Rare encounters; deep-water conditions deteriorate for recreational fishing.
