White tail spiders come out in search of food during warm summer weather, and their numbers are up, according to some pest controllers.
White tails, which can inflict a painful bite, top the list of pests homeowners want eradicated.
As soon as the temperature topped 25C, the phone started ringing, said Gisborne's Stomp'em Out Pest Control owner James Guyton.
The amount of white tails had been worse this summer and there were a lot of children being bitten, he said.
"There were only one or two children that I came across last year but this year there have been about nine or 10, and quite a few adults.
"Last year, it wasn't often we went over 24 degrees but this year we are into 28 and 29-degree temperatures, and the hotter the weather, the more prolific the white tails."
Mr Guyton said bedrooms, wash houses and bathrooms seemed to be the main places white tails liked to lurk.
"They like the moist areas."
Osbornes Bugs Eastland owner-operator Eamon Osborne had also noticed an increase in demand for white tail extermination services.
"They're a hot climate insect and the warmer weather makes the numbers increase.
"Last year, it was German cockroaches and white tails, but this year it is just the white tails."
Kurt Loklindt, of Target Pest Control in Christchurch, said he had also had the usual increase in white tail spider jobs this summer.
"What normally happens this time of year is because it's warmer the spiders come out of hibernation and end up going through doors and windows to feed on other spiders in the voids. They end up in people's houses and people end up getting bitten quite a bit more."
He'd had 10 to 20 spider jobs a week this summer, with about 80 per cent being for white tails.
Chris Crean, from Buzzz Off Pest Management in Auckland, said he was receiving upwards of 10 jobs a week involving white tails, about the same as previous summers.
"Everybody's got windows and doors open this time of year so there's more seen around," he said.
The National Poisons Centre said the number of reported white tail spider bites had remained about the same over the past six years.
In the period from January 2011 to December last year, the centre received 117 inquiries about unidentified spider bites and 37 calls involving white tail spiders where the caller was able to identify the species.
John Fountain, a medical toxicologist at the centre, said there was a misconception about white tails.
"There's been a lot of myth put out that a bite can lead to very nasty ulcers and skin lesions et cetera. This is not actually the reality.
"We hear from a lot of people who believe they've been bitten by a white tail spider because they've got some sort of painful area that's developed and they attribute that to a spider when, in fact, that's highly unlikely."
The centre received the highest number of calls about white tail spider bites following media reports on the subject, he said.
What do white tail spiders look like?
Dark grey spiders are 12-17mm long and readily recognised by a distinctive white patch on the end of the abdomen.
Are their bites dangerous?
According to the Ministry of Health, most white tail spider bites are harmless but occasionally a severe reaction may result in a deep ulcer.
What should you do if bitten?
It is better to see a doctor soon after the bite. To relieve stinging and swelling use ice or apply an anti-sting ointment.
Additional reporting: Sophie Rish-worth of the Gisborne Herald