Lessons from a Tiri Visit

The second GBICT sponsored visit of islanders to Tiritiri Matangi took 17 interested locals for a high speed ride into a unique reserve.  David Speir went along for the experience of a rat-free island.

Environmental News Issue 5

The forecast wasn’t that crash hot: nor’westerlies freshening with a frontal change to the SW. A familiar story but the intensity factor is not so easy to predict — so it was with some trepidation we gathered at Tryphena Wharf.

Once on the boat John O bribed us nicely with bacon and tomato sandwiches so we would meekly fill in his questionnaire. By 8.00am we were away with D’Saro’s twin Cummins diesels making short work of the NW chop as we charged toward Tiritiri. Captain Paul Downey’s boat has a seakindly twenty knot plus motion; and before we knew it we were rounding Tiri heading into the wharf on the SW side of the Island. The local DOC ranger met and briefed us before we split into two parties for our guided ramble. There was no overt search of my bag for rats or mice or turning out of my pockets a la Hauturu.

First impressions were of a pristine gulf island – low, fairly uniform native cover and orderly pathways to follow. The beach approaches were well sign-posted – it would be difficult to land here oblivious to the status of the island. There were none of the usual rubbish signatures of our modern world evident as we walked initially along the coastal past some innovative blue penguin nesting boxes. No roaming dogs here to cut short their breeding efforts. One of the first things evident was the profusion of berries on understorey species – we have the same shrubs and trees here but something else is taking that food. The local birds were soon right around us. It’s no small leap of experience to meet a saddleback in the person after a lifetime of seeing just the banknote image.

The birds – saddlebacks, bell-birds, robins, red crowned parakeets, stitchbirds and white-heads seemed not quite tame but relatively relaxed in this dense low habitat. Some were easier to locate than others but all were present in a density quite unknown to this writer. Our group encountered an unfledged (and unidentified) chick perched purposefully on a low branch. He would have been a quick snack for Mickey Rat where I come from. A slightly unreal representative of primeval NZ – a takahe (his name was Greg ) who strode purposefully down the path toward us, examined us for potential food offerings and finding none headed on to meet the next tour from the Kawau Kat.

The efforts of the many to replant this island, were hard to comprehend but easy to appreciate. A remnant of the bland grassland that the island was sits at the very apex of the landform, a vivid reminder of what faced the first groups of revegetators. The uniform height of the vegetation and the lack of tall trees told the story – this island had been mostly denuded. Even now the lack of suitable old, tall forest inhibits species like kaka from breeding here – they need the puriri hollows for nest spaces. Tiri is much drier than Aotea, it lacks the mountainous terrain to precipitate rainfall, so has little wetland habitat and few permanent streams.

It quickly dawned on me that habitat restoration can be crossed off the Barrier’s to do list – no need. We have superb intact habitats from wetlands to dense mature forests of varying makeup. We are in another league altogether. Trackwork in the creative sense is not that necessary either – we already have an excellent network. Visitor facilities we have of various styles and budgets – much of it under utilized away from the summer peak.

But absent from Tiritiri Matangi and in abundance on Aotea is the silent and mostly unseen predator, food consumer, and competitor for nearly all of our bird, reptile and invertebrate species – rattus rattus the black rat, aka. the tree rat, aka the ship rat. A prehensile, rapidly breeding omnivore whose population is limited only by the food available but whose densities can easily attain 50 per hectare.

We enjoyed (again courtesy of the Trust) a packaged lunch in the Visitor Facility near the Tiri Light and mixed with a larger group of visitors off the Kawau Kat. Our return hike to the wharf took us right past a small group of kokako – awesome. And now we had to go. I kept thinking how great it would be to stay overnight and hear the chorus at dawn.

The Sou’wester blew hard on our tail as we surfed home on the boisterous gulf swells.

Thanks D’Saro; thanks GBICT.