Many bird species incorporate spiders into their diets. This dietary inclusion is common among insectivorous birds and even some omnivores. Spiders provide beneficial nutrients, making them a valuable food source for birds, particularly during certain life stages.
Birds That Actively Hunt Spiders
Many bird species actively hunt and consume spiders. Insectivorous birds frequently include spiders in their diet. Examples include wrens, sparrows, blackbirds, robins, bluebirds, and blue tits. Omnivorous birds, such as crows and jackdaws, also consume spiders.
Birds employ various methods to capture spiders. They might swoop down to snatch a spider from above or chase it along the ground or on a tree. Some agile species can pluck spiders directly from their webs or capture them mid-flight. For instance, swallows are known for their aerial acrobatics, allowing them to catch spiders during flight.
Smaller, more nimble birds like warblers and sparrows can hover briefly to grab spiders and other prey from webs that are out of reach from perches. Wrens are particularly adept at foraging for spiders in dense foliage, tree bark crevices, and even within window wells. Brown creepers use their curved bills to find spiders hidden in tree bark.
Once a spider is caught, birds typically use their beaks to crush it. They generally consume a wide variety of spider species, with availability in their habitat determining which ones are eaten.
The Role of Spiders in a Bird’s Diet
Spiders offer distinct nutritional advantages for birds. They are rich in protein and fats, providing a high-energy and nutritious meal. This nutritional value is especially beneficial during periods of high activity, such as migration, or during the breeding season when birds require ample energy for themselves and their offspring.
Spiders also contain taurine, an amino acid that plays a role in the development of young birds. Research indicates that chicks fed a diet rich in spiders exhibit bolder personalities and improved learning abilities as adults. This suggests that adult birds may selectively feed spiders to their young to influence their offspring’s development and behavior.
While spiders are a valuable dietary component, they are often a supplemental or opportunistic food source rather than a primary one for most bird species. For many insectivorous birds, caterpillars, beetles, and other insects form the bulk of their diet during the breeding period. Spiders become particularly important when readily available, acting as a consistent food source throughout the year in many habitats.
For some species, like Blue Tits and Great Tits, spiders can constitute a substantial portion of their chicks’ diets, sometimes up to 75%. Parent birds prioritize soft, nutrient-packed items like spiders for their nestlings because they are easy to digest.