ISLANDS = RATS?
When we arrived on the island over six years ago, we discovered we also shared the tiny green isle with rats. Their droppings littered the floors of the empty buildings, nibbled plastic packets of butter (the type you get with your muffin at a café) were strewn about the back kitchen and ‘The Fishermen’ visitors reported seeing a rat climb out a window as they made breakfast.
We thought rats were just part of island life. Nigel was baiting ad hoc with no results.
Then the rat problem escalated. There were more droppings, even out in the open – ‘The Fishermen’ asked if we had rabbits? One night time I was awoken by a strange scratching sound – I couldn’t figure it out. Eventually we found the gnawed polystyrene under our kitchen sink where rats were getting inside by climbing from the ground up the kitchen sink drainpipe and through a gap in the floor. They were trying to gnaw their way out of the kitchen cupboard. We plugged the hole.
Still they came back, one night gnawing through the polystyrene at the back of the fridge and into the plastic – making a hole you could stick your finger through. The gnawing of the plastic woke us up and when we went to investigate a dark shadow raced to the sliding door exit, while Nigel lept onto the couch and Georgie dog ran about in a frenzy and I – quite blind without my contact lenses – was completely oblivious.
On my walks I would catch sight of a dark round shape in the grass; was it a baby Weka or a rat?
I snapped a photo of what looked like a squirrel in the grass – but it was a rat standing on its hind legs; laughing.
I reported regularly to Nigel my discovery of rat footprints on the beaches; sometimes resembling a little rat highway along the edges of the concrete reinforcements. But Nigel remained firm, rat baiting was his domain and if I didn’t like how he was doing his job I could go back to the city.
In the summer evenings Georgie and I would go for a ‘ratting’ walk mid-way up the island around the Quad we would see the rats in the trees and running under the buildings, so I filmed it all.
THE TIDE CHANGES
Then about this time three things happened that changed the rats rule.
One morning I discovered a recent clutch of Dotterel eggs on the front beach had been destroyed overnight; and there were rat prints (as well as gull prints) all over the sand around the nest. Dotterels are an endangered, endemic species in New Zealand. The shore birds – about the size of a Starling – lay their nests in a scrape of sand about the high tide mark and are at risk of predation from Black Backed Gulls, and the usual introduced pest suspects – rats and mustelids. On this island apart from the Gulls, their only other predators were rats.
That was the final straw for me; I made up some new rat bait stations myself, baited them and placed them around the front beaches. Each morning all the bait was gone, so I’d rebait and I kept on rebaiting.
Then while I was logging some of my film footage, Nigel sat down to watch. I was playing back some of the scenes I’d caught of the rats in the trees and scampering across the grass, of Georgie chasing a rat under a building and losing sight of it.
Then Nigel received a phone call from Mike, a local Councillor who introduced himself. Mike is passionate about the local islands and amongst other things asked about our rat situation.
THE BATTLE COMMENCES
So, with military precision Nigel began the battle against the rats. He tripled the amount of bait stations, setting them out precisely around the island, GPS-ing their coordinates and drawing up a huge map of the stations locations. He made up a notebook and diligently recorded which stations he rebaited. He checked stations almost daily, sometimes I’d trail around after him, making notes in the notebook. A few weeks later no baits were being taken.
In early 2013 members of the Council and Bio-security team visited the island with Tui the ‘rat dog’. They set up some rat traps and educated us on how to set up and monitor tracking tunnels.
I hadn’t seen a tracking tunnel before; a long square plastic tunnel in which we placed a tracking ink card. These ‘Gotcha’ ink cards and tunnels were invented by an inspiring New Zealander, Warren Agnew.
The cardboard cards fitted neatly into the bottom of the tunnels. In the centre of the card is wet ink, where we lay the peanut butter lure. Both ends of the card are white cardboard; so any critter who ventures inside the tunnel and eats the lure leaves their inky footprint behind for identification. These tracking tunnels help us identify if any rogue rat has made it to the island.
When the ‘rat team’ returned a few months later they couldn’t find any evidence of rats. I’d identified rat prints in one tracking tunnel on the far back beach; and then nothing.
The ‘rat team’ visit annually to check and after three years without a trace of a rat we were officially declared pest free.
The chances of a rat swimming ashore – from a boat or another island – are still quite high, so we remain vigilant.
After almost a year away, to look after another island, we returned in early 2015, and I slipped seamlessly into the role of volunteer predator controller, combining checking stations and tunnels with my daily and weekly walks and beach combing.
I also kayak out to a rock island in front of us, weather permitting, and check the bait stations there.
We have less bait stations set up now, (and more tracking stations) and they’re new Weka-friendly designed stations. The brodifacoum bait is deadly to Weka; even if they ate a poisoned rat.
Using toxic bait is certainly not my personal preference, but it’s what we’ve been supplied with for the job. I’d prefer to use a humane trap – like the Good Nature ones.
We also share the island with Weka and the tracking tunnels aren’t Weka proof. Weka are chicken-sized, flightless birds, endemic, endangered and also fond of peanut butter. They are also very smart. I staple the tracking cards to the tunnel, otherwise the Weka pull the cards out to get to the peanut butter. Weka will also squeeze themselves into a tracking tunnel to eat the peanut butter lure, sometimes without leaving a footprint, other times stomping all over the ink card rendering it useless. The more ‘Weka-proof’ I make the tunnels (by closing up the ends with gaffer tape, or a metal rod) the more determined the Weka are to get to the peanut butter lure; pulling the whole tunnel away from its tethers and to make their displeasure known they drag the tunnels away to the beach so the tide washes the tunnels out.
So a delicate balance continues; enough Weka-safe bait stations around the island to possibly kill any rat that swims ashore; without harming the local Weka. Maintaining tracking stations to identify any rogue rat, while trying to find a way to keep the Weka from hi-jacking the tracking stations.
Upon reflection I think we went through all the typical stages of ‘newbie’ pest controllers:
- Oblivious of the rats then>
- Aware then >
- Frustrated, angry, indignant then >
- Taking action then >
- Having no results then >
- Taking coordinated, educated, effective action then >
- Having positive results then >
- Becoming pest control advocates J
- Keeping up the effort, voluntarily; and looking for better, more humane answers for rat control.
The positives for being pest free is a noticeable increase in young seedling growth in the native bush areas – and I’m sure I hear more birds singing.
I’m Fiona (Fe). For the past six years I’ve lived on tiny, privately owned Islands in New Zealand with my partner who is an Island caretaker. I’ve developed Islomania (an obsessional enthusiasm or partiality for islands); particularly around bird life, beach clean-ups and pest eradication.
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