Huntsman spiders are a frequent sight across Australia, recognized by their substantial size and rapid movements. These arachnids, belonging to the family Sparassidae, do not build webs for hunting; instead, they actively pursue prey. Their flattened, hairy bodies and legs splayed in a crab-like fashion can be startling. Despite their intimidating appearance, understanding their behavior and ecological role often shifts perception from fear to acceptance.
Widespread Presence Across Australia
Huntsman spiders are common throughout Australia, inhabiting nearly all states and territories. Approximately 200 different species are found across the continent. Their presence extends from arid deserts to lush rainforests and even cooler sub-alpine zones, showcasing their broad environmental adaptability. They are frequently encountered in various settings, including natural bushland, rural properties, and extensively in urban and suburban areas.
These spiders often seek shelter in narrow spaces, such as under loose tree bark, within rock crevices, or beneath logs. Their flattened bodies allow them to fit into tight spots, which is why they are commonly found hiding behind curtains, under furniture, or in wall cracks inside homes. It is not uncommon for them to be discovered in cars, sometimes even behind sun visors or scuttling across dashboards. While some species are widespread, others are more restricted to specific regions.
Factors Contributing to Their Commonality
The widespread prevalence of huntsman spiders in Australia is attributed to their adaptability to diverse climates and habitats, alongside other biological and environmental factors. They are opportunistic predators with a generalist diet, feeding on a variety of insects and other invertebrates like cockroaches, moths, and beetles, which are abundant. This broad diet ensures a consistent food supply.
Reproductive strategies also contribute. Female huntsman spiders produce a flat, oval egg sac, often containing up to 200 eggs. The female guards this egg sac diligently for about three weeks, protecting her offspring until they hatch, and often remains with her spiderlings for several weeks after hatching, providing further protection. Some species, like Delena cancerides, are social, living in large family groups that share meals and cooperate to raise young, enhancing survival rates. Their ability to coexist with human development, often finding shelter and food sources in anthropogenic environments, also supports their commonality.
Living Alongside Huntsman Spiders
Encounters with huntsman spiders are common for Australians. They are frequently found inside homes, particularly on walls and ceilings during warm or humid weather, or seeking refuge from rain. Australians also report finding them in garages, sheds, and vehicles. Despite their size and speed, huntsman spiders are generally not aggressive towards humans and prefer to flee when approached.
Their venom is mild, primarily used to immobilize insect prey, posing little danger to humans. Bites are rare and usually occur only if the spider feels threatened or cornered, with symptoms typically limited to localized pain and swelling. Many Australians recognize the beneficial role huntsman spiders play as natural pest controllers, consuming common household insects like cockroaches and mosquitoes. This understanding often leads to peaceful coexistence, with spiders left undisturbed to help manage insect populations.