LIBBY HAMILTON, KENT
Stage 1: The egg sac
In the spring, female spiders start to produce egg sacs. These silky, cocoon-like constructions can each contain up to 70 eggs, and a female spider can produce as many as 10 egg sacs over her lifetime.
Stage 2: Spiderling
Juvenile spiders, known as spiderlings, hatch from the eggs and undergo their first moult inside their egg sac. When they’re ready to emerge, they cut a hole in the sac and escape, temporarily staying close by before dispersing.
Stage 3: Moulting
Each spiderling must go through up to eight moults before they reach adulthood and sexual maturity. Before each moult, the spider withdraws to a quiet area and stops feeding for a few days. Beneath its outer layer, a new, softer exoskeleton is forming while enzymes start to dissolve the inner surface of the old one, almost as if it’s unfastening a suit made of Velcro. Gradually, the old exoskeleton splits open, and the spider peels off the old ‘suit’. The spider is soft and vulnerable but can expand in size while the new exoskeleton hardens.
Stage 4: Adult
Males reach adulthood and sexual maturity in late August and September after their last moult. It’s at this time of year we see them running around our homes. It’s a bit like the Love Island of the spider world, as house spiders try to couple up. Males roam looking for the more stationary females, picking up on chemical signals in the females’ spider silk that let them know she’s sexually mature.
Stage 5: Mating
Since spiders are carnivores, they’ve developed courtship rituals to ensure the female doesn’t mistake the male for prey. Once the male has been accepted by the female, he’ll co-habit the female’s web before mating. The male uses organs called pedipalps, located near his mouth, to give the female his sperm. She stores the sperm in her spermathecae organs, until she is ready to produce eggs next spring. The male spider dies as winter approaches, while the female overwinters in her web.
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