Spiders

Apart from widespread and sometimes pathological fear of spiders, the most common reason for control is the elimination of unsightly webs.

Spiders can be readily distinguished from insects: they have eight legs instead of six and they have two body segments instead of three – the head and thorax are fused into one unit which contains eyes, mouthparts and legs. The abdomen section is soft and houses the reproductive organs, the silk glands and spinnerets, and the respiratory openings which are visible on the under surface like the pages of a book. This large surface area achieves the transference of oxygen into blood. There are usually four pairs of eyes which are arranged in a pattern which is constant for each species and is therefore an aid to identification. The fine hairs on various parts of the body are said to be sensitive to taste, touch and vibration.

Most spiders, being nocturnal, are seldom seen during the day unless disturbed. Those which depend on webbing to snare their prey seldom move far and hide in a crevice, curled leaf or appear camouflaged as twigs. Hunting spiders such as the huntsman are not dependent on webs for food.

Whether the spider traps prey in a web or hunts to capture it, the victim is injected with venom through the fangs. This immobilises the prey. Most species can survive for months without food. This is just as well, as insect prey is usually scarce in the cold winter months.

Silk or web is produced from glands in the abdomen and deposited through spinnerets. In some species, spiderlings let out sufficient web into the air to lift them up on the breeze and carry them away.