Tag Archives: rodents

Hunting henriettas on Ruapuke Island – on the tail of New Zealand’s first mice

8 January 2013 – 11.16am

Few people are aware of Ruapuke Island. Guarding the eastern approaches to Foveaux Strait, the 1600 ha island is large enough to appear as a smudge of colour at the very bottom of TV3’s weather map. Yet the island’s low relief means that passengers on the Stewart Island ferry 20 km to the west barely notice it compared to the imposing bulks of Bluff Hill and Mt Anglem.

Henrietta Bay on the south coast of Ruapuke Island. The cannon is claimed to have come from the Elizabeth Henrietta. Image: Colin Miskelly

Henrietta Bay on the south coast of Ruapuke Island. The cannon is claimed to have come from the Elizabeth Henrietta. Image: Colin Miskelly

Ruapuke Island is privately-owned, mainly by descendants of the Kai Tahu chief Tuhawaiki. Most of the island is rough farmland (sheep and beef cattle), with a large patch of rimu / rata / kamahi / miro / kahikatea forest in the centre. Long sandy beaches separate granite and basalt headlands, with shallow lagoons lying behind several beaches.

Ruapuke was an important site for two of New Zealand’s earliest industries – the harvesting of fur seal skins and flax (harakeke) fibre. But the island has another more furtive claim to historical fame – or infamy. It was the first New Zealand site to be colonised by mice.

The brig Elizabeth Henrietta was engaged in the flax trade when it ran aground in Henrietta Bay on 25 February 1824. It was eventually refloated in August that year, but some time during its enforced stay, mice made it to shore. This was 6 years before the second recorded presence of mice in New Zealand, at the Bay of Islands in 1830. The residents of Ruapuke Island did not know what the strange creatures were, and reportedly referred to them as ‘henriettas’ after the ship they came from.

A mouse caught on Ruapuke Island. Image: Colin Miskelly

A mouse caught on Ruapuke Island. Image: Colin Miskelly

I was privileged to be invited to stay on Ruapuke Island at the tail-end of 2012. My hosts knew the significance of the island’s mice, and had been involved in the collection of tissue samples (i.e. mouse tail tips) for a genetic study that has confirmed that Ruapuke’s mice are from a different lineage to the rest of New Zealand’s mice. Yet during 188 years of mouse presence on Ruapuke Island, no specimens had reached Te Papa’s extensive collection of New Zealand rodents. Prepared with a selection of traps and baits, I spent 3 days trying to rectify this. It took some effort, as the mice were scarce (or wary), with two only caught in 27 corrected trap-nights. The main challenge was hiding the traps from inquisitive weka, which took 4 cheese baits, and would have taken any mice if I didn’t beat them to it.

A weka on Ruapuke Island. Image: Colin Miskelly

A weka on Ruapuke Island. Image: Colin Miskelly

Related blogs
Ruapuke Island – 1941 and 2012 – In the footsteps of Edgar Stead (Part 9)
Take that you dirty rat! – the unglamorous side of museum work

By Colin Miskelly | Posted in Biodiversity, Field trips, History, Mammals | Also tagged | Comments (1)

Our far South – Antipodes and Bounty Islands: dots of importance

8 March 2012 – 7.40am

I awoke on the morning of 6 March to discover that we had very rapid progress over night and were approaching the rugged columnular basalt cliffs of the Antipodes Island, crowned with green tussocks. The home to the Antipodean albatross,the Antipodes Island parakeet and the erect-crested penguin (to name just a few of the birds!). It is almost pest free, but sadly mice still live in this barren place.

Bounty Island shag. Photo Anton van Helden, copyright Te Papa.

Furseal. Photo Anton van Helden, copyright Te Papa.

The only native mammals found on shore here are elephant seals and the New Zealand and Sub-Antarctic furseals. 1804 saw the first sealing gang arrive at the Antipodes. This American gang killed about 60,000 seals over the course of the year they were stationed on the islands. While the location of prime sealing grounds was jealously guarded at the time, the evidence they took home led to a sealing boom on the islands.

After 1807 sealing was occasional and catches small. By the 1830s seals were all but wiped out and sealing in the Antipodes came to an end.

Incredibly sealing in the Southern oceans saw some 7 million furseals (Arctocephalus spp.) were killed for their skins. Essentially by 1830 all populations of furseals were so depleted to make fursealing unecomonic.

Bounty Island shag. Photo Anton van Helden, copyright Te Papa.

Populations of furseals have bounced back, but interestingly it seems that the Bounty Islands may be the main breeding area with the Antipodes islands being primarily a haul-out area.

The erect-crested penguins endemic to the islands, and like many penguin species, they are showing signs of decline.

Once again after a night of travel we found ourselves in the early hours of the morning at our next location, the jagged and totally inhospitable looking Bounty islands.

Bounty Islands.

These are projections of rock sticking out of the sea, yet home to numerous furseals, Salvin’s albatross and their very own shag.

Sadly we could not go ashore on Spider island in the group to look for the species of Spider that Phil Sirvid would have liked me to collect.

Sadly our trip now is coming to an end and this will be my last blog post from the boat. It will be weird to be on land again in just a couple of days.

Salvin’s albatross. Photo Anton van Helden, copyright Te Papa.

By antonvanhelden | Posted in Biodiversity, Birds, Field trips, Mammals, Penguins | Also tagged , , , , , | Comments (1)

Take that you dirty rat! – the unglamorous side of museum work

20 October 2011 – 1.22pm

The position of Curator Terrestrial Vertebrates was a new one for Te Papa in mid 2010. My predecessor had been the Curator of Birds, and the expanded role meant that for the first time a curator would be responsible for land mammals, as well as for birds, reptiles and frogs. It didn’t take long to discover the logic behind the new job description…

Waiting in a corner of the spirit collection area were two fork-lift pallet loads of long-neglected rodent specimens. Most had been collected by members of the former Ecology Division DSIR and New Zealand Wildlife Service. They had been donated to the National Museum during the massive government service restructurings of the late 1980s that resulted in the creation of successor agencies Landcare Research and the Department of Conservation.

Kiore caught in snap trap, Taranga (Hen Island). Photo: Colin Miskelly, Te Papa

Despite the turmoil of restructuring and job losses, both the Department of Conservation and Landcare Research embarked on two decades of developing huge advances in pest eradication techniques. Most notable were developments in the application and use of anticoagulant baits to eradicate four species of introduced rodents from ever larger islands. As an unexpected consequence, those two unloved and nearly forgotten pallet loads of festering and desiccating specimens contained many examples of rodent populations that are now extinct.

A kiore specimen being prepared for preservation in the field, Taranga (Hen Island), December 2010. This population has since been eradicated by the Department of Conservation. Photo: Colin Miskelly, Te Papa

Between 1987 and 2007, kiore (Pacific rats), Norway rats, ship rats and house mice were eradicated from over 90 islands around New Zealand, ranging in size up to 11,300 hectare Campbell Island. Examples of rats and mice from many of these islands were in jars on those two pallets, but until they were catalogued and entered into Te Papa’s electronic database, there was no easy way to determine which of the extirpated rodent populations were represented in the national collection.

Tom Schultz checking collection details on a rat specimen in the Te Papa spirit collection. Photo: Colin Miskelly, Te Papa

With the help of Natural Environment collection technician Tom Schultz over the last 4 months, all the samples have been sorted, and decisions made on which to keep as spirit specimens versus prepared as skeletons versus sent to the landfill. All 664 spirit specimens that we chose to keep have been labelled, placed in jars of ethanol in the spirit collection, and all their data entered in the EMu electronic database.

Rat specimens in the Te Papa spirit collection. Photo: Colin Miskelly, Te Papa

We now know that among the 323 kiore, 77 Norway rat, 52 ship rat and 212 house mouse spirit specimens are examples of 43 populations that have been eradicated for conservation reasons. Extirpated populations represented include:

Kiore (Pacific rat) Rattus exulans: Kermadec Is (Raoul & Macauley), Moturua I. (Bay of Islands), Lady Alice I. (Chicken Is), Taranga (Hen I. – eradication yet to be confirmed), Mokohinau Is (Burgess I., Trig I., Stacks C, D & F), Tiritiri Matangi I., Little Barrier I., Cuvier I., Mercury Is (Red Mercury, Stanley, Double & Korapuki Is), Ohena I., Middle Chain I. (Aldermen Is), Mayor I. (Tuhua), Rurima Rocks, Kapiti I., Long I. & Motuara I. (Queen Charlotte Sound), Centre Island (Foveaux Strait), Codfish I. (Whenua Hou), and Putauhinu I.

Norway rat Rattus norvegicus: Raoul I., Bay of Islands (Motukiekie, Moturua, Okahu, Urupukapuka & Waewaetorea Is), Motutapu I., Whale I. (Moutohora), Breaksea I. (Fiordland), and Campbell I.

Ship rat Rattus rattus: Rangitoto I., Big South Cape I. (Taukihepa), and Macquarie I. (eradication yet to be confirmed for latter).

House mouse Mus musculus: Allports I. (Queen Charlotte Sound), Enderby I. (Auckland Is), and Macquarie I. (eradication yet to be confirmed for latter).

By Colin Miskelly | Posted in Biodiversity, Mammals | Also tagged , , | Comments (2)
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