Not every hedgehog owner thinks to offer fish, and honestly, it’s not a staple food for a reason — hedgehogs are insectivores, not pescatarians. But fish is a legitimate protein source that most hedgehogs can handle without any issue, provided you choose the right kind, prepare it correctly, and don’t overdo it. The answer is yes, with a few things worth knowing first.
Fish in a Hedgehog’s Diet
Hedgehogs in the wild eat insects, the occasional small invertebrate, and whatever else they stumble across while foraging at night. Fish isn’t a natural part of that picture. That said, cooked fish is a complete protein source — rich in animal-based protein and omega-3 fatty acids — which means it falls within the category of foods a hedgehog’s digestive system can handle and benefit from.
As the experienced owners on Hedgehog Central note, most fish that are commonly available are safe to offer: salmon, whitefish, sardines, cod, trout, and mackerel all fall into this camp. It’s not a food that needs to be avoided — it just needs to be offered sensibly. For a broader understanding of what a hedgehog’s protein needs actually look like, our what hedgehogs eat guide covers the foundations in full.
The Mercury Question
This is the part of the fish conversation most hedgehog articles skip past, and it deserves real attention. Mercury accumulates in fish through a process called biomagnification — larger, longer-lived predatory fish consume smaller fish repeatedly over their lifetimes, building up higher and higher concentrations of mercury in their tissue. For a small animal like a hedgehog, even modest mercury exposure from regularly eating high-mercury fish could be genuinely harmful over time, potentially causing nerve damage and kidney problems.
The practical upshot is straightforward: stick to low-mercury fish and avoid high-mercury species entirely.
Low-mercury fish — good choices: Salmon, sardines, cod, tilapia, trout, anchovies, and herring. According to FDA and EPA fish guidance, these species consistently rank among the lowest in mercury content and are safe for regular human consumption at two to three servings per week. For hedgehogs, offered only occasionally, the mercury exposure from these species is negligible.
Moderate-mercury fish — offer rarely if at all: Albacore tuna, halibut, mahi-mahi, and snapper. These are fine for humans once a week, but given how small a hedgehog is and how infrequently fish should feature in their diet anyway, there’s little reason to reach for these species when better options are available.
High-mercury fish — never: Swordfish, shark, king mackerel, and tilefish. These have no place in a hedgehog’s dish. As the Alaskan Salmon Company’s mercury guide explains, the mercury levels in large predatory fish stem directly from a lifetime of consuming other fish — exactly the kind of cumulative exposure a hedgehog’s small body has no buffer for.
Standard canned tuna sits in an interesting middle ground. Skipjack tuna (the kind in most canned light tuna) has relatively modest mercury levels, while albacore has considerably more. Given that hedgehogs should only receive fish occasionally and in small amounts, canned light tuna in water — not brine, not oil — is probably fine as a very occasional option. Canned albacore is better avoided.
The One Side Effect to Know About
There’s something veteran hedgehog owners mention consistently that doesn’t always make it into care guides: fish can cause noticeably smellier poop. It’s not a sign of digestive distress, and it doesn’t mean the fish is harming your hedgehog — it’s simply how some hedgehogs process fish protein. As confirmed by multiple contributors on Hedgehog Central’s fish discussion thread, there’s nothing nutritionally wrong with feeding fish, but the poop factor is real and worth knowing about before you start.
If your hedgehog’s enclosure already has a strong smell, adding fish to the diet might not be the quality-of-life improvement you were hoping for. For everyone else, it’s a minor consideration rather than a dealbreaker. Our guide on do hedgehogs smell bad covers the broader odour question if you want more context.
How to Prepare Fish for Your Hedgehog
Preparation matters here more than most people realise. A few non-negotiable rules:
Always cook it. Raw fish carries a real risk of bacterial contamination — including Salmonella and Vibrio vulnificus — and should never be offered to hedgehogs. Baking, steaming, or poaching are all appropriate cooking methods. Avoid frying, which adds unnecessary fat and often involves oil that isn’t suitable for hedgehogs.
No seasoning whatsoever. Salt, garlic, lemon, butter, herbs, sauces — none of it. Plain and simply cooked is the only way to go. Many common seasonings that are harmless to humans are genuinely toxic to small animals.
Remove all bones. Fishbones are a choking hazard and can cause internal injury if swallowed. Check the flesh carefully before serving, and offer only boneless portions.
Cut it small. Flake the fish into small, manageable pieces rather than offering a large chunk. A few small flakes at a time is plenty.
Skip canned fish in brine or oil. If you’re using tinned fish, choose varieties canned in water only, with no added salt. Even a small amount of the sodium levels in brined fish is more than a hedgehog needs.
Leave any uneaten fish in the enclosure for no more than a couple of hours. Fish spoils faster than most foods, and you don’t want your hedgehog eating something that’s been sitting out in a warm cage overnight.
What About Fish-Flavoured Cat Food?
This comes up often and the answer is generally positive. Many hedgehog owners use a quality pea-free cat kibble as the base of their hedgehog’s diet, and some of those formulas are fish-flavoured. According to feeding guidance from Vale Wildlife Hospital — one of the UK’s leading wildlife rehabilitation centres — the claim that hedgehogs shouldn’t eat fish-flavoured cat food is a myth. There’s no meaningful nutritional difference between fish-flavoured and other flavours, though some hedgehogs simply don’t find fish-flavoured kibble as appealing.
The same rules apply to wet fish cat food: choose a high-quality product with fish as the primary ingredient and no artificial preservatives, and avoid anything with excessive fillers, salt, or mystery additives. Our best hedgehog food guide has recommendations if you’re evaluating options.
How Often Can Hedgehogs Eat Fish?
Fish should be an occasional treat rather than a dietary fixture — a few times a month at most, alongside the insect-based protein and quality kibble that should form the core of your hedgehog’s meals. The are hedgehogs good pets article has a good overview of the general care commitment involved, including feeding routines, if you’re still building out your understanding of hedgehog ownership.
A small portion — think a teaspoon or two of flaked fish — is appropriate for an adult hedgehog. More than that, and you start running into the digestive and mercury considerations we’ve already covered.
The Best Fish to Start With
If you want a reliable starting point, cooked salmon or sardines are hard to beat. Both are consistently among the lowest-mercury fish available, both are rich in omega-3 fatty acids, and most hedgehogs respond well to the flavour. Sardines in particular have the advantage of being inexpensive, easy to find canned in water, and highly nutritious for their size. Just rinse them thoroughly before serving if they’re canned, even in water, to remove any residual salt.
Cooked cod and tilapia are also solid, neutral-flavoured options that are easy to prepare at home and unlikely to provoke any digestive upset.
Conclusion
Fish is a safe, protein-rich occasional treat for hedgehogs when it’s the right kind, properly cooked, and offered in sensible amounts. Stick to low-mercury species like salmon, cod, sardines, and trout; cook it plain without seasoning; remove all bones; and keep portions small and infrequent. The main thing to manage is the smellier poop that sometimes follows — which is more of an inconvenience than a health concern — and the importance of never offering raw or high-mercury fish.
As you build out a balanced diet and care routine for your hedgehog, having the right feeding setup makes the whole process easier. Our best hedgehog products page covers everything from feeding bowls and food options to the full range of care essentials your hedgehog’s setup needs.