By Ella DaviesThe summer heat might be fading but things are hotting up for house spiders.
If you’re not afraid of them, autumn is the best time of year to see one of the arachnids as males come out of their usual hiding places in search of a mate.And according to the Society of Biology, which has launched a new recording scheme, the spiders may have started early.
Thanks to a smartphone app they have already received 3,000 reports – including sightings in August – but there have been few previous studies of this kind for accurate comparison.
Dr Geoff Oxford from the University of York and the British Arachnological Society cites his paper published in 1987 that suggested sightings of house spiders peaked in late September but the spiders’ movements were not recorded earlier in the year, so their exact behavioural patterns remain to be revealed.
Dr Rebecca Nesbitt and colleagues at the Society of Biology hope that by encouraging people to study spiders they can shed light on their seemingly mysterious habits.
To make it easy for citizen scientists to record spiders on their patch, the biologists have released a phone application to gather valuable data for scientists in situ – and get to know the spiders we share our homes with.
“We are trying to collect as much data as possible from around the UK. It is amazing how much there is still to discover about even the animals that live closest to us, but scientists can’t collect this much information alone,” said Dr Nesbitt.
There are five closely related species of house spider in the UK from the genus Tegenaria which means “mat” in reference to their sheet-like webs.
These are the large brown spiders you sometimes see scuttling across the kitchen floor or stuck in the bath.
“When male large house spiders stop in the middle of a room, they are not planning who to scare next, as often assumed. They are just exhausted,” explains Dr Oxford.
“Like a cheetah they can run very fast for a short distance, and then have to stop to recover.”
Although they sometimes live indoors, these spiders are most likely to be found living in sheds or wood piles.
Males are easy to identify due to the pedipalps protruding from their head – structures that resemble boxing gloves which are used to transfer sperm to females.
“I find large house spiders a fascinating group of species. They are awesome and beautiful to examine close up,” says Dr Oxford.
“From a research angle, some of the species hybridise and provide a fascinating window on geographical distributions and the evolution and possible fusion [or loss] of species through hybridisation.”
He also adds that spiders play an important role as “nature’s safest insecticides”: snacking on midges, mosquitoes and other insects.
The recording scheme encourages the public to photograph and identify the spiders they find and provides information on the most frequently encountered species.
Dr Oxford lists the following as the ten spiders you’re most likely to encounter around your home: Large house spiders (T. saeva and T. gigantea), the common house spider (T. domestica), the cardinal spider (T. parietina) in the south of England, the daddy long legs spider (Pholcus phalangioides), the European garden spider (Araneus diademata) and orb-weaver (Zygiella x-notata) can often be found on windows, lace web weavers (Amaurobius similis and A. fenestralis) live in the crevices of external walls and on hot days the black and white striped jumping spider (Salticus scenicus) hunts on exposed walls. – BBC Environment
