NZ robins lose fear of predators

New Zealand robin populations have been found to lose their fear of rats after only one generation in a predator-free environment, raising questions about the reintroduction of birds from island sanctuaries to the mainland.

Researchers Ian Jamieson and Karin Ludwig from Otago University compared robins on Stewart Island, where Norway rats are common, with birds on Ulva Island, where rats were eradicated in 1996.

The birds on Ulva are descendants of birds from the Stewart Island population, and Ulva does have native predators – the flightless weka and a native owl.

A report on the research, published in Animal Behaviour, said the Stewart Island robins were more agitated than the Ulva birds in the presence of a rat model, and were more hesitant about approaching mealworm food, which they tended to collect one at a time.

Many of the robins on Ulva appeared to show little fear or recognition of the model rat and were much less agitated and more likely to consume all five mealworms in a shorter time, despite the nearby model rat.

Vigilance and antipredator behaviour were costly for the birds, as they needed to be traded off against other activities, such as feeding or resting, the report said.

New Zealand robins appeared to possess proper antipredator behaviours, such as mobbing and alarm calling, but needed to learn to recognise a mammalian predator as a specific threat.

If experience were important to develop predator recognition, then isolation for just one generation would have a significant effect on the performance of a population. That seemed to be the case for Stewart Island robins reintroduced to rat-free Ulva, the report said.

“These results raise the question of whether established populations on island sanctuaries are appropriate sources for harvesting for reintroductions back to the mainland.”

While predator-naïve birds might be more likely to forage in the presence of a potential threat, as long as some individuals survived an initial attack that incident might be enough to restore predator recognition capabilities.

Original story on

The Nature Collection


To celebrate NZ’s unique natural taonga, Peter Hayden has curated a highlights collection from three decades of NHNZ productions. Aotearoa’s landforms and its magnificent menagerie of natural oddities – birds, insects, trees like nowhere else on the planet – are showcased in 15 award-winning titles. From Discovery Channel and David Bellamy, to Wild South and Our World classics.

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Weka on the menu

Wednesday, 3 February 2010, 10:00 am
Press Release: Federated Farmers

Media Release
3 February 2010

This bird is a Weka, which is also the name of a well-known suite of machine learning tools.

Reasons to farm weka

Federated Farmers is backing entrepreneurial farmer, Roger Beattie, in his quest to secure trial approval to supply farmed weka.

“Here’s a true Kiwi entrepreneur who ought to have every policy encouragement to see if a new market can be created,” says Donald Aubrey, Federated Farmers game spokesperson.

“Mr Beattie firmly believes that the weka can be domesticated and if that’s the case, it could well become our version of the turkey. After all, that’s a bird native to the Americas that is now commonly farmed around the world. The turkey was domesticated around 500BC.

“I think the reaction from TVNZ’s Close-Up on Monday evening shows New Zealanders are open-minded to new possibilities. 85 percent of respondents felt Mr Beattie should be given the room to try. We do, too.

“New Zealand is a unique country and it stands to reason that our fauna has the unique potential to be farmed as well. As Mr Beattie rightly points out, no farmed species has ever become extinct. Really, it’s the complete opposite when it comes to farming.

Full press release on

Baby Tuatara Hatches on Matiu/Somes Island

Thursday, 28 January 2010, 11:12 am
Press Release: Department of Conservation

A photograph taken of a baby tuatara on Wellington Harbour’s Matiu/Somes Island this month has confirmed for the first time that the rare reptiles are hatching on the island.

The juvenile, just a few months old and about 8cm long, was spotted by Harriot (8) and Nicholas Lane (10) and their cousin Harrison Vernon (11) while they were walking around the island with their grandparents Bob and Suzanne Vernon.

Tuatara were transferred to Matiu/Somes in 1998 and since then adult tuatara are regularly seen on the island. It has long been suspected that they are breeding, and this was finally proven when eggs were found on the island in 2007 and hatched at Victoria University.

But this is the first confirmation that young tuatara have hatched on the island itself.

full media release on

Scientists play tag with whitebait species

Wednesday, 9 December 2009, 9:44 am
Press Release: NIWA

Draft NIWA MEDIA STATEMENT 9 December 2009

Catch me if you can! Scientists play tag with whitebait species

New Zealand’s iconic whitebait species are disappearing from our waterways, but help could soon be at hand for the threatened giant kōkopu. Scientists are carrying out a trial involving ‘tagging’ of individual farm raised fish as part of a plan to reintroduce them to our waterways.

The National Institute of Water and Atmospheric Research (NIWA) and Mahurangi Technical Institute (MTI), who will be providing the fish, have been engaged by the NZ Transport Agency and its Northern Gateway Alliance (NGA) partners to undertake a project as part of the mitigation programme associated with the recent construction of the Agency™s SH1 toll road. Together they aim to repopulate a stream in Orewa with giant kÍkopu. The giant kÍkopu is one of five galaxiid fish species which, in their juvenile form, make up the whitebait catch and is classified by the Department of Conservation as nationally vulnerable.

full press release on