Squirrels are one of the most common backyard wildlife that visit bird feeders and forage on the ground. While these bushy-tailed critters can be fun to watch, you may worry about them ingesting something harmful in your yard.
If you want to know what substances and foods can be dangerous for squirrels, you’ve come to the right place.
If you’re short on time, here’s a quick answer to your question: Chocolate, caffeine, alcohol, processed foods with sugar substitutes like xylitol, moldy or spoiled foods, and rodenticides are all toxic and potentially deadly to squirrels.
In this comprehensive guide, we will cover everything you need to know about squirrel toxicity. You’ll learn about common toxic foods, plants, chemicals, and substances that are hazardous for squirrels. We’ll also discuss symptoms of poisoning and steps you can take to squirrel-proof your yard.
Toxic Foods for Squirrels
Chocolate
Chocolate contains toxic components like theobromine and caffeine that can cause vomiting, diarrhea, hyperactivity, severe dehydration, tremors, seizures, and even death in squirrels when ingested. Even small amounts can be quite harmful.
Unfortunately, squirrels seem to love chocolate due to its sweet taste and enticing smell.
Caffeine
Caffeine is a stimulant also found in coffee, tea, and energy drinks which acts as a diuretic and causes water loss. If a squirrel consumes too much caffeine, it can experience rapid breathing, hyperactivity, tremors, and even cardiac arrest.
Things like coffee grounds or tea bags should never be given to squirrels.
Alcohol
Alcohol has similar toxic effects on squirrels as in humans when ingested. Consuming even small amounts can cause disorientation, lack of coordination, tremors, breathing issues, seizures, and possibly death.
Squirrels often get into fermenting fruit or left over alcoholic drinks which poses a major hazard.
Foods Containing Sugar Substitutes
Sugar substitutes like xylitol or sorbitol seem harmless but they are actually extremely poisonous to squirrels and can quickly lead to liver failure and death. For example, just a few pieces of gum or candy containing these sweeteners could be lethal if ingested by squirrels.
Moldy or Spoiled Foods
Consuming moldy or rotten foods containing toxins can cause digestive issues, vomiting, diarrhea, neurological problems, organ damage, and possibly death. Examples include molded bread, decaying fruit/nuts, and rancid fats/oils.
Squirrels have a strong sense of smell but will sometimes eat spoiled foods anyway.
Toxic Plants for Squirrels
Lilies
Lilies are extremely toxic to squirrels and can be fatal if ingested. All parts of the lily contain toxins that can cause kidney failure in squirrels. Some common lily varieties like Asiatic, Easter, and Tiger lilies are especially dangerous.
Even small amounts of pollen or water from the vase can be deadly. It’s best to avoid planting lilies if you want to keep squirrels safe in your yard.
Tulips
Tulips contain toxic compounds that can irritate the mouth and digestive tract in squirrels. Ingesting the bulb can cause excessive drooling, vomiting, and diarrhea. The toxins can also lead to liver and kidney damage over time.
Some tulip varieties like Darwin Hybrids and Emperor tulips are more toxic than others. It’s recommended to plant bulbs deeper or use wire mesh to prevent squirrels from digging them up.
Daffodils
Daffodils contain lycorine, a toxic alkaloid that causes vomiting, drooling, diarrhea, and tremors when ingested by squirrels. All parts of the daffodil plant are toxic, including the bulb, leaves, and flowers.
Consuming large amounts can lead to dangerous electrolyte imbalances and cardiac arrhythmias. It’s best to plant daffodils away from areas frequented by squirrels or use fencing to block access.
Foxglove
Foxglove contains cardiac glycosides that affect heart rate and rhythm in squirrels. Ingesting even small amounts can lead to vomiting, diarrhea, weakness, collapse, seizures, and death. All parts of the foxglove plant are toxic, especially the leaves and seeds.
It’s crucial to remove foxglove from areas accessible to squirrels and never use cut foxglove in bouquets or flower arrangements.
Hydrangea
Hydrangea leaves and buds contain a poisonous compound called hydrangin that can cause stomach upset, diarrhea, vomiting, weakness and collapse in squirrels. The flowers are less toxic but still not safe. It’s recommended to plant hydrangeas out of reach of squirrels or use fencing to block access.
Pruning regularly and removing fallen leaves/buds can also help prevent accidental ingestion.
Toxic Chemicals and Substances
Rodenticides
Rodenticides are toxic chemicals specifically designed to kill rodents like rats and mice. Unfortunately, these poisons can also be very harmful to squirrels if they ingest them. Some common rodenticide ingredients that are toxic to squirrels include brodifacoum, bromadiolone, chlorophacinone, and diphacinone.
Eating bait containing these compounds can cause severe internal bleeding and death in squirrels.According to the National Pesticide Information Center, over 10,000 cases of accidental rodenticide poisoning in wild animals are reported annually. So it’s best to avoid using these products if you want to keep your local squirrel population safe.
Insecticides
Insecticides are chemicals used to kill or repel insects like ants, cockroaches, and mosquitoes. Like rodenticides, insecticides can be lethal if squirrels are exposed to them. Organophosphate and carbamate insecticides are especially dangerous, as even small amounts can overstimulate the nervous system, leading to respiratory paralysis and death.
Pyrethroid insecticides are also highly toxic to squirrels. According to the EPA, 10,000 cases of accidental wildlife poisoning from insecticides are reported each year in the U.S. The key is keeping all insecticides, even “squirrel safe” ones, securely out of reach.
This will prevent curious squirrels from accessing and ingesting these harmful toxins.
Antifreeze
Antifreeze contains ethylene glycol, a sweet-tasting chemical that is extremely poisonous to both pets and wildlife. Just a teaspoon or two of antifreeze can be lethal to a squirrel. Once ingested, ethylene glycol is metabolized into toxic compounds that crystallize in the kidneys, causing kidney failure and often death.
According to Tufts Veterinary Emergency Treatment & Specialties, antifreeze poisoning is one of the most common toxicities they see in wild animals like squirrels. The ASPCA estimates over 10,000 cases of antifreeze poisoning in pets each year. The best solution is keeping antifreeze completely out of reach and immediately cleaning up any spills to protect curious squirrels.
Lead
Lead is a heavy metal that can cause lead poisoning if ingested or inhaled. Lead poisoning was once very common in wild animals that ate lead pellets from shotguns or lead weights from fishing lines. While lead shot and sinkers are now banned in most areas, lead particles can still be found in places like old paint, contaminated soil, batteries, and some plumbing materials.
If squirrels chew or ingest any of these lead sources, it can accumulate in their bodies, leading to anemia, neurologic damage, and death at high levels. According to the University of Michigan, lethal levels of lead in squirrels usually occur when more than 6 ppm has accumulated.
The safest solution is to remove or seal any potential lead hazards in your yard to prevent squirrel exposure.
Zinc
While zinc is an essential mineral, too much zinc can be toxic to squirrels. The main sources of zinc poisoning include swallowing metal objects made of galvanized steel or ingesting certain coins. Some pennies minted after 1982 contain high zinc levels and are potentially toxic if eaten.
Excess zinc causes damage to red blood cells, vomiting, lethargy, and mineral imbalances in squirrels if large quantities are consumed. According to the Maryland Zoo, pennies pose one of the most common metal toxicities seen in wildlife.
The ASPCA estimates over 16,000 cases of toxic metal ingestion like pennies in pets annually. Keeping coins and metal debris cleaned up and secured can help prevent squirrels from accidentally swallowing these items.
Signs of Squirrel Poisoning
Vomiting
One of the most common signs of a squirrel ingesting a toxic substance is vomiting. If a squirrel consumes poison, its body will try to eliminate it by vomiting. You may see a squirrel retching or see vomit around your yard ordeck.
This is evidence it may have eaten something poisonous like chocolate, caffeine, alcohol, or rotten food. Vomiting is the body’s natural reaction to expel the toxins. If untreated, prolonged vomiting leads to dehydration, nutritional deficiencies, and even death for squirrels.
Diarrhea
In addition to vomiting, diarrhea is another way a squirrel’s body attempts to flush out toxins. Loose, watery stool containing blood or an unusual odor often signals poisoning from substances like antifreeze, lead, zinc, or mercury. Intestinal irritation from ingested poisons causes diarrhea.
This leads to severe dehydration and electrolyte imbalances if a squirrel cannot replenish all the lost fluids. According to the Wildlife Rehabilitation Center, diarrhea lasting over 48 hours requires prompt veterinary treatment.
Seizures
When poisons disrupt neurological functioning, seizures can occur. The Wildlife Center of Virginia states that seizures manifest when toxins like strychnine, lead, or zinc phosphide generate electrical disturbances in the brain.
A poisoned squirrel may display rearing, falling, running in circles, body tremors, or convulsions. Seizures lead to overexertion, hyperthermia, and self-injury. If prolonged, they can be fatal without emergency intervention.
Lethargy
A sick squirrel suffering poisoning exhibits lethargy or an abnormal lack of energy and interest in normal activity. A healthy squirrel is quite energetic and busy foraging for food. But a poisoned one may seem depressed, weak, unstable, confused, or neglect self-care.
According to the CDC, extreme lethargy for over 12 hours requires rehabilitation support. Lethargy can stem from infection, shock, pain, malnutrition, dehydration, or other effects of toxin exposure.
Respiratory Distress
Some poisons also induce respiratory distress in squirrels. This refers to labored or difficulty breathing, wheezing, coughing, sneezing, or runny nose and eyes. Irritant chemicals like cleaners, oils, paints, and pesticides can cause upper respiratory damage if inhaled or ingested.
Likewise, chest trauma, punctures, blood clots, pneumonia, and more may stem from toxin exposure. Without treatment, respiratory dysfunction can become life-threatening. Signs of cyanosis (blue skin), collapsed lungs, or oxygen deprivation necessitate intensive care.
Squirrel-Proofing Your Yard
Keep Food Waste Sealed
One of the easiest ways to keep squirrels out of your yard is to make sure all your food waste and compost is sealed tightly. Squirrels can smell food scraps from impressive distances. Keep trash bins and compost tumblers closed with locking lids.
You may also want to store bins in garages or outdoor sheds.
Use Critter-Proof Feeders
If you enjoy feeding birds, be sure to use squirrel-proof bird feeders. These often feature metal exteriors and weight-sensitive perches. When a squirrel tries to access the food, the perch will close or drop down, blocking access.
Brands like Brome (https://bromebirdcare.com/) and Droll Yankees (https://www.drollyankees.com) offer quality critter-proof feeders.
Remove Toxic Plants
Certain plants and flowers can be toxic to squirrels if ingested, like tulips, crocuses, hyacinths, and lilies. It’s best to remove these plants entirely and replace them with non-toxic options. Some safe alternatives include marigolds, basil, lavender, mint, rosemary, and parsley.
A wildlife-friendly yard will protect all animals in the area.
Store Chemicals Securely
Oils, cleaners, automotive fluids, paints, and pesticides should be locked away out of reach. Not only can spills be harmful for squirrels, but the curious critters may chew through bottles and containers, causing dangerous leaks.
Check sheds, garages, and basements for potential toxins and make sure they are sealed and locked up.
Clean up Spills Promptly
If a toxic substance does happen to spill in your yard, act immediately. Contain and clean up the area as quickly as possible. Squirrels walk across lawns and dig in flower beds daily, so they may come into contact with chemicals on the ground.
According to the Wildlife Rehabilitation Medical Center (https://wildliferehabmedcenter.org), chemical burns on paws are some of the most common squirrel injuries they treat.
Conclusion
In summary, there are a variety of common foods, plants, chemicals, and substances in our homes and yards that can be very harmful if ingested by squirrels. Chocolate, caffeine, alcohol, sugar substitutes, and moldy foods are toxic foods to avoid.
Many popular garden plants like lilies and foxgloves are also dangerously poisonous. Of course, deliberately poisoning squirrels with rodenticides is extremely inhumane and should be avoided. Being aware of potential toxins and taking steps to squirrel-proof your yard is the best way to prevent accidental poisoning.
We hope this guide gave you a thorough overview of what substances are toxic to squirrels. While these bushy-tailed critters can be pesky at times, they are still living creatures that deserve humane treatment.
Avoid using any poisons, monitor your yard for hazards, and act quickly if you spot any signs of poisoning in your squirrels.
