The Department of Environmental Protection has issued guidelines to the public on how to correctly identify black and brown widow spiders.

In the latest edition of the Department’s Envirotalk newsletter, plant protection officer Claire Jessey describes the “distinctive orange-red or red hourglass shaped marking on the underside” of the belly of the female black widow — the far more dangerous of the two spiders.

She writes that female brown widows have a “yellowy-orange to orangey-red hourglass shape on the underside of their large spherical abdomen.”

Ms Jessey says the egg sac is the best way to identify a widow spider: black widow egg sacs are round to pear shaped, white or cream, with a smooth surface, while brown widow egg sacs are off-white to tan and round, with many tufts of silk sticking out, giving a spiky appearance.

The newsletter states: “Over the last several years, members of the public have been presenting specimens of the brown widow spider (Latrodectus geometricus) for identification with the concern that they are black widow spiders (Latrodectus mactans).

“And although we have had a few incidents of black widow spiders on imported grapes and bananas in the past, it is an unusual occurrence and the spiders in those situations were captured and destroyed.

“Similarly, an inspection of a housing estate in Southampton in 2009 revealed spiders that appeared to be black widows. However, they were ultimately identified by a University of Florida spider expert as exceptionally dark brown widows.

“Black widow spiders are not known to be established on the Island. However, their cousins the brown widows are present in every parish.

“The brown widow spider is not considered to be a ‘dangerous’ spider in spite of its toxic venom, as they are extremely reluctant to bite, so their presence should not itself be cause for alarm.

“As there has been some interest in the media recently regarding spiders, including black widows, being intercepted in fresh produce, and given the high vigilance of the public to spiders in general, it is worth knowing the difference between our local brown widow population and the black widows.”

The Department advises “extreme caution” when handling a live suspect black widow specimen and says images of spiders and egg sacs can be e-mailed to Ms Jessey at cjessey@gov.bm for identification.