Tuesday, November 4, 2008

What’s biting you?

Understanding - and escaping - the dreaded New Zealand Sandfly.

The New Zealand bush comes with good news and bad news on the bugs front: The good news is that, unlike in Australia, none of our insects will kill you. The bad news is the sheer quantity of one bug – the sand fly – may, with their tenacious and persistent biting, drive you to kill yourself.

Maori legend has it that Hinenui-te-po, goddess of the underworld released the sand fly near Milford Sound to prevent humans becoming idle and freezing to death in the face of Fiordland’s natural beauty. These days the little bloodsuckers are found wherever there’s flowing water and bush – most of the country really.

The female sand fly, which are the ones that bite (read into that what you will) live for about six weeks, in which time they have to hatch, develop as larva while feeding on aquatic algae and bacteria then metamorphose into flying insects, mate and feast on blood to get the sustenance required to lay eggs in a fast flowing stream to perpetuate the cycle. It’s a pretty short life, and getting a meal of your blood is one of the highlights – so it’s really no surprise that they’re so enthusiastic about it.

If you don’t want to be bitten, and don’t mind resorting to nasty chemicals, insect repellents with a high concentration of DEET are best. But remember it’s a strong solvent so will do horrible things to plastics (like your expensive outdoor gear) and has known side effects including; seizures, confusion, acute psychosis, nausea and vomiting and skin irritation. It’s also suspected of being a contributing element in Gulf War Syndrome.

If you plan to have a long and healthy outdoor career the herbal repellents are a better option. There is a range of products out there that work almost as well as the DEET based stuff, without the stress about contracting some awful ailment down the track. Be warned though, some of the best contain lavender oil which can sometimes result in exchanging sand flies for bumble bees!

Covering up as much as possible with light-coloured clothing will minimise the need for repellents. Tuck your trousers into your socks, wear thin polypropylene gloves and a fine head net then put your bug repellent of choice on any exposed bits left - and you’ll be sweet as bro!

If you want to explore some alternative bug solutions, some people think that consuming large doses of Vitamin B gives your sweat a repellent quality. I'm also told the early loggers in Fiordland apparently drank a glass of diesel each day to achieve the same effect. However, I’ve never had much luck with the Vitamin B theory… and I’ve never tried the diesel approach!

Once you’ve been bitten expect some pretty nasty mosquito bite style welts to arrive within a few days. Calamine lotion works well for the itching, but really all you can do is leave them alone, and console yourself with the fact that your body develops an immunity to sand fly bites over time, so each bite makes you a little bit better prepared for the next.