Tips for visiting a pest-free island

By Jess MacKenzie

“You have to think like a seed,” Gemma said as she turned the insides of my trouser pockets out with a long, narrow piece of metal.

“I struggle to think like a human,” I pointed out as she dug deep into the corners. (I’d like to note that I wasn’t wearing the trousers at the time.)

“Here,” she said, and sure enough she’d found the remnants of an earlier tramping trip somewhere – golden grass seeds that had burrowed themselves deep into the seams. They had survived several journeys through the washing machine and my apparently sub-par attempts at pocket-emptying. I felt a little embarrassed.

“I’m sorry you had to see that,” I said. Then, “Maybe I should check my boots again…”

I’d done quite a good job on the outside of my boots, but there was plenty hiding underneath the inner soles. Gemma, well-versed in biosecurity as part of her island role rangering with DOC, did a stellar job with a miniature vacuum cleaner. I suspect my boots were cleaner than when I first bought them.

When you go to a pest-free island, you need to be conscious of all the things you’re taking with you. Just one invasive seed that makes it through biosecurity quarantine could start to grow on the island – exactly where it’s not wanted. It can spread and compete with native species, altering habitat for native plants and animals.

Stowaways like rats, mice, ants and plague skinks also predate. A single rat can quickly decimate a vulnerable population on an island and it can take years to recover.

Microorganisms found in soil and dust can also cause huge problems. Myrtle rust is one example of a pathogen that lives in soil and we’ve seen the impact that can have.

Islands have borders, making them ideal to clear of pest species and turn into havens. But those borders can be breached. Keeping the native species on these islands safe depends on vigilant visitors.

DOC have a rigorous biosecurity process for visiting their offshore pest-free islands. But there are many public islands around New Zealand anyone can go to – and it’s your responsibility to help protect them amazing place you’re about to visit.

So I thought I’d share some tips from my biosecurity quarantine experience, to help you prepare and do your bit when visiting a pest-free island.

1. Use the biosecurity checklist

You can find a biosecurity checklist on the DOC website. This outlines what you need to consider and do before leaving. It was also my first step in preparing to head out to the island.

2. Only take what you need.

Every pocket and corner is a chance for something to sneak in with you. Before you go, think about what you actually have to take. Be prepared and know before you go, but don’t overpack.

3. Clean your boots.

Your boots are in the prime position for hosting hitchhikers. Things can get stuck in the soles, in the shoelaces, in the tongue, or just in the boot itself. (My brother once found a mouse in his gumboot. After he put the gumboot on…)

We used SteriGENE (a hospital-grade disinfectant) on our boots, as well as any other gear that might have been in touch with animals. You may not have SteriGENE, but you can do a good job with a thorough scrub in soapy water.

4. Think like a seed – or any pest species.

Go through all your gear in detail. Turn your pockets inside out. Undo all zips and give everything a shake out – your pack, your sleeping bag, your tent, your sunglasses case. Where there’s soil get in there with a hearty scrub, and if it’s an item you’ve had in storage for a while give it an extra check in case things have snuck in.

Check your woolen clothes and socks. Socks are notorious. I spent a good forty-five minutes picking seeds out of my socks. I recommend My Generation: The Best of the Who as a soundtrack to get stuck in.

If you’re heading over to the island in a kayak or boat, you’ll also need to ensure you give it a thorough check. You’re also more likely to get stowaways like rats or mice so it pays to really take your time.

5. Get a friend to double-check.

This was an important part of our quarantine. Gemma checked my gear, and with my new knowledge and pointy pocket-turning implements I was able to check someone else’s with equal meticulousness. As noted at the start, that extra pair of eyes can make a huge difference.

Before you head out, get someone to check. If you’re going with a friend swap bags, or find someone else to have a look before you go.

6. Seal it tight.

Once we’d checked our gear, it went into yellow waterproof buckets for the boat journey across. This meant that absolutely nothing could get inside. We even had a bucket for clothes we were going to wear on the boat trip, which we only took out on the day of the journey.

You can make sure anything you’ve prepared is sealed tight. Keep your food in sealed containers to avoid attracting insects. Do all zips up securely so nothing can sneak in.

Don’t open it until you arrive.