false_false_widowsNews stories about false widow spiders are an annual occurrence, but this year the coverage has been far more persistent, with more sensationalised, unsubstantiated and downright nonsense stories than usual. With over 650 species of spider in the country but very limited public awareness there is little appreciation of the diversity of spiders, and any spiders vaguely resembling false widows (and some spiders looking nothing like false widows), are being identified as such by the press and subsequently members of the public, and vice versa since it seems fact-checking by journalists is rare. Having said that, false widows are fairly common and widespread in the South, and have been around for some time.

There are a number of spiders considered ‘false widows’, but the species the name usually refers to, Steatoda nobilis, was first recorded in 1879 in Devon, and is believed to have been imported with bananas from the Canary Islands. We cannot be sure when it first became established, but in recent decades there is evidence of a range increase, possibly because of climate change. It has been well established from Cornwall to Essex since at least 1990. The situation at present is no different to what it has been for many years – the only difference this year is that many more people are aware of them, and looking for them owing to the media coverage. In actuality, given that March 2013 was one of the coldest on record, it is more likely that we have fewer of them this year than last.

Steatoda nobilis, and the more widespread but less common Steatoda grossa, are capable of biting people when feeling threatened (as can about a dozen spider species found in the UK), though it would appear from their relative abundance in many urban areas and the number of verified bites that such an occurrence is extremely rare – they prefer dark undisturbed corners and flee given the chance. Reactions to the bite can vary, and in a few very rare instances people have had allergic reactions. Some of the recent stories have involved bacterial infections with no spider spotted at all – a case of media scaremongering perpetuating itself and people self-diagnosing using the internet!

For more information:
http://wiki.britishspiders.org.uk/index.php5?title=False_Widow_Spiders

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