Pest Free Great Mercury Island

I was lucky enough to be invited to join the Moehau Environment Group (a long established group who work with predator control in the northern Coromandel Peninsula) on one of their walks across part of Great Mercury Island along with Pete Corson of Department of Conservation and Andy Hopping – the resident Ranger on the island.  The purpose of the walk was to see and talk about the effects since the pests were eradicated on the island in 2014 – and enjoy the absolutely stunning scenery and bays along the way.

We learnt that without rats or cats (there has never been possums or stoats on the island) a number of things have flourished:

And really this is only some of the examples of change and is only the beginning of what this island can become.  For us scuba divers here in Whitianga, the benefits will likely extend to increased flora and therefore fish life along the coast of this island, as increases in seabird life and their fertilisation of the foreshore and sea fringes has downstream benefits.

The really important thing is for you – our boating population – to really be mindful when visiting this island and even if you intend to anchor just off any of the Mercury Island group, that you are maintaining pest control on your vessel and you are extremely careful not to harbour any pest in any bag or container that could escape onto these islands.

• Tips to help keep your boat free of pests:
• Keep your boat tidy and clean.
• Don't leave rubbish or fish scraps on board.
• Before departure, inspect your boat for signs of rats and mice, eg chewed wiring or holes in gear or bags, and for insects (especially ants).
• Owners of larger vessels are encouraged to maintain pest control on board. Use glue boards for insects, and traps or bait stations for rodents.
• All food should be packed in sealed containers. Don't just use open shopping bags or cardboard boxes as these are known to harbour pests.
• Do your loading in daylight hours. Most pests are active at night and will come aboard then.
• Vessels should stay anchored offshore except for embarking and disembarking passengers. Tenders are OK as long as you inspected them for pests before arrival.

These steps will help keep the Mercury Islands pest-free and could also save you from pest damage on board your boat.

At the end of our walk Sir Michael Fay (one of the owners of the island) met us and it was great to hear his enthusiasm to continue this project and protect this very special part of our local environment and such an important jewel in the efforts for species preservation and protection.

If you are interested in volunteering on the island for a 5 day stint working on the projects they have going on there you can contact Andy Hopping, Ranger.

For more information

Peter Corson, Project Manager
Ahuahu-Great Mercury Island Pest Eradication
Whitianga Field Base, Department of Conservation
PO Box 276, Whitianga 3542
Email: pcorson@doc.govt.nz

Pre-eradication there were 7 – 8 breeding pairs of Dotterals on the island.Today there are 25 breeding pairs and each of these had 3 eggs this season and likely to hatch them all and raise these babies.The national average for a breeding pair is less than 1.

Kaka have flourished in the bush and we saw and heard many of these beautiful parrots flying through the trees.

Kakariki have increased too and their calls were numerous.

Bumble bee populations have exploded – they burrow underground and were targeted by rats.Bumble bees are great pollinators – better than honey bees.

The island is home to the biggest amount of snail species in the country and it is thought they are increasing in numbers.