According to Gram Research analysis, nearly all European hedgehogs (92%) eat slugs and snails as their primary food, but this diet exposes them to dangerous toxins. A 2026 study of 209 hedgehogs found that those eating more slugs had significantly higher levels of toxic zinc and rodent poison in their livers, revealing how environmental pollution spreads through food chains and threatens these already-endangered animals.
Scientists studied what European hedgehogs eat by analyzing their droppings and found that almost all hedgehogs eat slugs and snails. While this is their favorite food, the research revealed a concerning problem: slugs are picking up dangerous chemicals like rodent poison and zinc from the environment, and then passing these toxins to hedgehogs when they eat them. The study of 209 hedgehogs across Europe shows that hedgehogs eating more slugs had higher levels of toxic chemicals in their livers, which could be harming these already-threatened animals.
Key Statistics
A 2026 research article analyzing the diet of 209 European hedgehogs found that slugs and snails appeared in the diet of 92% of individuals, making them the most frequently consumed food source.
According to the 2026 study of 209 hedgehogs, invasive Spanish slugs were found in the diet of 80% of individuals, and these slugs are known vectors of parasitic lungworms and accumulate high concentrations of environmental contaminants including zinc and rodenticides.
A 2026 analysis of 209 European hedgehogs revealed that diet richness was negatively correlated with brodifacoum (rodent poison) levels in the liver, suggesting that hedgehogs eating more diverse foods had lower toxin exposure.
The 2026 study of 209 hedgehogs found that the relative abundance of slugs and snails in the diet was positively correlated with hepatic zinc concentration, indicating that slug consumption directly increases toxic metal exposure.
The Quick Take
- What they studied: What do European hedgehogs eat, and does their diet connect to poisoning and disease?
- Who participated: 209 European hedgehogs from various locations across Europe. Scientists identified what they ate by examining their feces using DNA testing.
- Key finding: Slugs and snails appear in 92% of hedgehog diets and are their most common food. However, hedgehogs eating more slugs had higher levels of toxic zinc in their livers, and slugs also carry rodent poison that builds up in hedgehogs.
- What it means for you: This research matters for hedgehog conservation. It shows that environmental pollution is reaching hedgehogs through their food chain, particularly through slugs. While this doesn’t directly affect humans, it highlights how pollution spreads through nature and why protecting hedgehogs requires reducing environmental toxins.
The Research Details
Scientists collected fecal samples (droppings) from 209 hedgehogs living in various European locations. Instead of trying to identify what the hedgehogs ate by looking at their stomach contents, they used a modern DNA technique called metabarcoding. This technique reads the DNA fragments in the droppings to identify exactly which animals and insects the hedgehogs had eaten. The researchers then compared what each hedgehog ate with measurements of toxic chemicals found in the hedgehogs’ livers to see if diet and toxin levels were connected.
This approach is much better than older methods because it doesn’t require killing animals to examine their stomachs. The DNA method can identify tiny pieces of food that would otherwise be unrecognizable. The scientists also measured how much of each food type appeared in each hedgehog’s diet and looked for patterns based on where the hedgehogs lived.
This research method is important because it gives scientists a clear picture of what wild animals actually eat without harming them. By connecting diet information to toxin measurements, the study reveals how pollution moves through food chains—a critical insight for protecting endangered species like hedgehogs. Understanding these connections helps conservation experts develop better strategies to protect hedgehogs by reducing environmental toxins.
The study examined a reasonably large sample of 209 hedgehogs across multiple European locations, which strengthens the findings. The use of DNA metabarcoding is a well-established, reliable scientific technique. However, the study is observational, meaning it shows correlations (connections) between diet and toxins but cannot prove that eating slugs directly causes toxin buildup—other factors could be involved. The research was published in a peer-reviewed scientific journal, meaning other experts reviewed it before publication.
What the Results Show
The study revealed that slugs and snails are by far the most important food for European hedgehogs, appearing in the diet of 92% of the animals studied. Earthworms were the second most common food (54%), followed by beetles (54%), moths and butterflies (48%), and grasshoppers (54%). Interestingly, about 29% of hedgehogs had also eaten pet food, likely from human sources.
The most concerning finding was the connection between slug consumption and toxic chemicals. Hedgehogs that ate more slugs had significantly higher levels of zinc in their livers. Additionally, hedgehogs eating more slugs showed higher levels of brodifacoum, a rodent poison widely used in agriculture and pest control. This suggests that slugs are accumulating these toxins from the environment and passing them to hedgehogs through the food chain.
A particularly worrying discovery was that Spanish slugs (an invasive species) appeared in the diet of 80% of hedgehogs studied. These slugs are known to carry parasitic worms that cause lung disease in hedgehogs and accumulate high concentrations of environmental toxins. The research found that slug consumption was most common in areas with high rainfall, possibly because slugs thrive in wet conditions.
Surprisingly, the study found no connection between hedgehog diet and infection with two specific pathogens tested: Corynebacterium ulcerans and circovirus. This suggests that what hedgehogs eat doesn’t directly increase their risk of these particular infections. However, the study did find that hedgehogs with more diverse diets (eating a wider variety of foods) had lower levels of brodifacoum in their livers, suggesting that dietary variety may offer some protection against toxin accumulation.
Previous research on hedgehog diet relied on examining stomach contents or fecal analysis under a microscope, which provided less detailed information. This study’s use of DNA metabarcoding confirms earlier findings that slugs and snails are the primary hedgehog food but provides much more precise identification of what species they eat. The finding that environmental toxins accumulate in hedgehogs through their diet is consistent with broader research showing how pollution moves through food chains in nature. However, this is one of the first studies to specifically document how slugs act as toxin vectors to hedgehogs.
The study shows correlations between diet and toxin levels but cannot definitively prove that eating slugs causes toxin buildup—other factors like where hedgehogs live or their overall environment could play a role. The research measured toxins at only one point in time for each hedgehog, so it cannot show how toxin levels change over time. The study also didn’t measure all possible toxins, only brodifacoum and zinc. Additionally, the sample sizes for some food types were small, which limits conclusions about less common foods. Finally, the study was observational and couldn’t control for all variables that might affect hedgehog health.
The Bottom Line
Based on this research, conservation efforts should focus on reducing environmental toxins, particularly rodenticides and heavy metals like zinc, that accumulate in slugs and snails. Habitat management that encourages dietary diversity in hedgehogs may help reduce toxin exposure. Controlling invasive Spanish slug populations could reduce both toxin exposure and parasitic infections. These recommendations have moderate to strong support from this research but would benefit from additional studies. Individual hedgehog lovers can help by avoiding rodent poisons in their gardens and creating diverse habitats with varied food sources.
Wildlife conservationists, environmental scientists, and policymakers should prioritize this research when making decisions about pesticide use and habitat protection. Gardeners and homeowners can apply these findings by avoiding rodent poisons and creating wildlife-friendly gardens. Veterinarians treating hedgehogs should be aware of potential toxin exposure through diet. The general public should care because this research illustrates how environmental pollution affects all wildlife through food chains.
Changes in hedgehog populations and toxin levels would take years to observe after implementing conservation measures. Reducing rodenticide use in an area might show effects within 1-2 years, but population recovery would likely take 5-10 years or longer. Individual hedgehogs’ toxin levels could change within weeks to months if their diet or environment changes.
Frequently Asked Questions
Are hedgehogs being poisoned by eating slugs?
Research shows hedgehogs eating more slugs accumulate higher levels of toxic chemicals like rodent poison and zinc in their livers. Slugs absorb these toxins from contaminated soil and water, then pass them to hedgehogs through the food chain, potentially harming the animals over time.
What do European hedgehogs eat most?
A 2026 study of 209 hedgehogs found slugs and snails in 92% of their diets, making them the primary food. Earthworms, beetles, moths, and grasshoppers were also common, each appearing in about 48-54% of hedgehogs studied.
Why are Spanish slugs bad for hedgehogs?
Spanish slugs, found in 80% of hedgehogs studied, carry parasitic worms that cause lung disease and accumulate high concentrations of environmental toxins like zinc and rodenticides. They’re an invasive species that poses multiple threats to hedgehog health.
Can eating different foods help hedgehogs avoid poison?
Research suggests hedgehogs with more diverse diets had lower rodent poison levels in their livers, indicating dietary variety may offer some protection against toxin accumulation by reducing reliance on contaminated slugs.
How can I help protect hedgehogs from toxins?
Stop using rodent poisons and pesticides in your garden, plant diverse native plants to support varied insect populations, and maintain natural areas with leaf litter. These actions reduce environmental toxins and provide hedgehogs with safer, more diverse food sources.
Want to Apply This Research?
- Track weekly hedgehog sightings in your garden along with environmental factors: rainfall, pesticide use nearby, and garden diversity (number of plant and insect species observed). Note any changes in hedgehog health or behavior.
- Create a toxin-free garden by eliminating rodent poisons and pesticides, planting diverse native plants to support varied insect populations, and maintaining areas with natural leaf litter where slugs and earthworms thrive. Log these habitat improvements in the app to track your contribution to hedgehog conservation.
- Over months, monitor whether your garden attracts more hedgehogs as you reduce toxins and increase diversity. Track seasonal patterns in hedgehog activity and correlate them with rainfall and garden conditions. Share observations with citizen science projects tracking hedgehog populations in your region.
This research describes patterns in hedgehog diet and toxin exposure but does not provide medical advice for hedgehogs or humans. The study shows correlations between slug consumption and toxin levels but cannot prove direct causation. If you find an injured or sick hedgehog, contact a local wildlife rehabilitation center or veterinarian. This information is for educational purposes and should not replace professional wildlife management or veterinary guidance. Always consult with conservation experts before implementing habitat changes intended to help wildlife.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.