The term “wood spider” is a common name encompassing a diverse group of arachnids that inhabit forests, woodlands, and gardens, including species like wolf spiders, orb-weavers, and funnel-web spiders. These creatures share a common role as ubiquitous and efficient predators within their ecosystems. Understanding what they consume and how they acquire their meals provides a clear picture of their function in the natural world, particularly in the control of insect populations.
Primary Prey: The Insect Diet
Wood spiders are primarily carnivorous, feeding almost exclusively on insects and other small arthropods that share their habitat. Their diet is largely governed by availability and the size of the spider, generally consisting of prey that is smaller than themselves. Common meals include soft-bodied insects such as flies, mosquitoes, moths, and springtails, which are easily subdued by venom.
Many ground-dwelling species, like wolf spiders, target crawling insects such as ants, small beetles, and crickets found in the leaf litter and on the forest floor. Some spiders are highly specialized feeders; for instance, the woodlouse spider (Dysdera crocata) possesses enlarged fangs specifically adapted to pierce the tough exterior of woodlice, which make up nearly its entire diet.
While insects form the bulk of their food source, larger woodland arachnids occasionally consume small vertebrates, including tiny frogs, lizards, or fish near water sources. Cannibalism is also a reality, as many spiders are opportunistic feeders and will consume smaller individuals of their own or other species if the chance arises.
Hunting Strategies and Prey Capture
Wood spiders employ two major strategies to secure their meals: active hunting and passive trapping. Active hunters, such as wolf spiders and jumping spiders, rely on speed, excellent vision, and stealth to track and overwhelm their prey. These spiders stalk their victims, often using patience and rapid movement before pouncing directly onto the target.
Wolf spiders use their keen eyesight and sensitivity to ground vibrations to locate prey, chasing them down before delivering a venomous bite. Jumping spiders use a burst of hydraulic pressure in their legs to launch themselves distances up to fifty times their body length, securing the prey with specialized front legs. This method bypasses the need for a web, as venom is injected immediately upon capture to paralyze the insect.
Passive hunters, like the orb-weavers and funnel-web spiders, rely on sophisticated silk structures to trap their food. Orb-weavers construct familiar, spiraled nets of sticky silk, waiting for flying insects to become entangled. Once vibrations signal a capture, the spider rushes out, quickly wrapping the struggling prey in a thick sheath of non-sticky silk before injecting venom.
Funnel-web spiders build silk-lined burrows with trip lines radiating outward. They wait inside the funnel retreat, sensing the vibrations of a passing insect before rushing out for a lightning-fast ambush.
Predators and Ecological Role
While wood spiders are accomplished predators, they also serve as a food source for a wide array of other animals, linking lower and higher tiers of the food web. Birds, such as wrens and robins, frequently consume spiders they find on foliage or the ground. Small mammals, including shrews and bats, and various reptiles and amphibians like lizards and frogs, also incorporate spiders into their diets.
The most specialized predators are the spider wasps (Pompilidae), which specifically hunt spiders. These wasps paralyze their victim with a targeted sting and then drag the immobilized body back to a nest or burrow. The spider serves as a living food source for the wasp’s developing larvae, demonstrating the spider’s complex position in the natural order.