For the past two years browntail moth larvae have made life miserable for the crew of Humber Lifeboat and their families stationed on the isolated headland.

The caterpillars carry up to two million spiked and barbed hairs which can penetrate skin and cause a strong allergic reaction and some of the crew, including coxswain Dave Steenvoorden, have suffered from almost constant chickenpox-like rashes. Even when supposedly dormant, they can still cause problems – two of the lifeboatmen's children recently got covered in rashes simply from playing outside and coming into contact with last season's hairs. There had been hope that numbers would naturally decline but this autumn bushes of sea buckthorn on the Point and at Kilnsea are grey with thousands upon thousands of nests full of overwintering caterpillars. Lifeboatmen fear next year could be the worst yet.

Yorkshire Wildlife Trust, which owns the headland, cannot use sprays on the protected site of scientific interest. In the past it has tried cutting and burning the nests but there are so many it has had little impact. Next month volunteers from Japan and Korea will spend two weeks chopping bushes down around lifeboatmen's houses.

Andrew Gibson, the trust's outer Humber officer, said: "Experience in other areas is that the population should have crashed – that at the moment doesn't seem to be the case. We didn't expect as many nests to be present at this time of year ."

Mr Steenvoorden said: "This year has probably been the worst, to be honest. What made it easier was the fact that we knew what to do so we managed it better – keeping the windows closed, not putting the washing outside and not having any work outside at all on the station for three months."

He said he was sick of being "fobbed off" by East Riding Council's public protection section. He said: " What I haven't got faith in is East Riding Council's public protection – we are the public and they just fob us off. They don't answer my phone calls... I have no faith at all (in the latest measure). They had a go at burning them before with a blowtorch and it didn't work. The only way of solving it is to completely spray – crop-dust it – from one end to the other and they won't do that because it's not selective and it is a special site of scientific interest."

Sally Burns, head of housing and public protection at East Riding Council, said: "The land belongs to the Yorkshire Wildlife Trust and is a national nature reserve. While the foliage remains there is little which can be done to remove the caterpillars. East Riding Council is working with the trust, which is taking the lead on the issue, and is pleased to act with them where they would like our input."