The natural diet of a squirrel consists of nuts, seeds, fungi, and insects, providing the precise nutrition needed for their active metabolism and survival. Human intervention often introduces readily available foods that can be detrimental to their health. Understanding which common foods pose a risk is important, as these opportunistic foragers are not protected from the dangers of the human food landscape. Inappropriate consumption can lead to acute poisoning, severe nutritional deficiencies, or debilitating digestive distress.
Items Causing Acute Toxicity
Some human foods contain compounds that are chemically toxic to squirrels and can cause immediate, severe, or fatal reactions. Chocolate and caffeinated products contain methylxanthines, such as theobromine, which squirrels cannot efficiently metabolize. This stimulant builds up rapidly in their small bodies, leading to hyperactivity, tremors, an abnormal heart rhythm, seizures, and potentially death. Caffeinated beverages, coffee grounds, and cocoa powder pose a similar danger due to their high concentration of these compounds.
Raw beans, particularly kidney beans, pose a threat due to the lectin phytohaemagglutinin. This toxin causes severe gastrointestinal distress and can interfere with cellular metabolism. While cooking neutralizes this compound, raw legumes are highly toxic, even in small quantities, potentially leading to vomiting and severe diarrhea.
Many fruit pits and seeds, specifically those from peaches, cherries, plums, and apples, contain cyanogenic compounds like amygdalin. When chewed or crushed, the compound is metabolized into cyanide, a fast-acting poison. Though the toxic concentration is low, a squirrel’s small body size makes them susceptible to poisoning if they break through the hard outer shell to access the kernel inside.
Moldy foods, including corn, peanuts, or bread, are hazardous because of the mycotoxins they harbor. Certain fungi, such as Aspergillus, produce aflatoxins, which are highly toxic carcinogens that attack the liver and suppress the immune system. Ingestion of these toxins can lead to acute organ dysfunction, internal bleeding, and sudden death.
Foods That Create Nutritional Deficiencies
A squirrel’s long-term health depends on a proper balance of minerals, particularly the ratio of calcium to phosphorus, which should be around 2:1. Foods high in phosphorus and low in calcium disrupt this balance, causing the body to pull calcium from its reserves to process the excess phosphorus. This depletion of skeletal calcium causes Metabolic Bone Disease (MBD), a common and preventable condition in squirrels fed an improper diet.
Common foods that are severely imbalanced include corn, peanuts, and sunflower seeds. While squirrels readily eat these, a primary diet of such items leads to rapid skeletal demineralization. MBD causes bones to become brittle and weak, resulting in pain, fractures, swollen joints, and neurological symptoms like seizures and paralysis.
The consumption of junk food, such as bread, crackers, and pasta, introduces empty calories without providing necessary vitamins, minerals, and protein. These high-carbohydrate items offer little nutritional value and cause the animal to feel prematurely full. This false sense of satiety prevents them from seeking the diverse foods required to maintain a healthy metabolism and strong bone structure.
Human Foods Causing Digestive Distress
Squirrels possess a delicate digestive system ill-equipped to process many manufactured human foods, resulting in severe gastrointestinal upset. Dairy products, like cow’s milk, are problematic because most adult squirrels are lactose intolerant. They lack the necessary enzyme, lactase, to break down the lactose sugar. Ingestion often leads to diarrhea, causing rapid dehydration and electrolyte imbalance, which is dangerous for small mammals.
Heavily refined sugars found in candy, baked goods, and processed snacks can overwhelm a squirrel’s system. These concentrated sugars disrupt the normal balance of gut flora, leading to painful digestive distress and potentially dangerous spikes in blood glucose. The lack of fiber and high caloric density of these items offer little more than immediate energy, displacing nourishing foods.
Foods high in sodium, such as salted nuts, chips, and processed meats, pose a significant risk to a squirrel’s kidney function. Their small kidneys are not efficient at filtering the high amounts of sodium found in these items. Excessive salt intake causes increased thirst and urination, and can lead to hypernatremia (salt poisoning), resulting in severe dehydration, muscle tremors, and organ stress.