A child walks past a geiger counter, measuring a radiation level of 0.162 microsievert per hour, at a square in front of Koriyama Station in Koriyama, west of the tsunami-crippled Fukushima Daiichi nuclear power plant, Fukushima prefecture March 1, 2014.
A child walks past a geiger counter, measuring a radiation level of 0.162 microsievert per hour, at a square in front of Koriyama Station in Koriyama, west of the tsunami-crippled Fukushima Daiichi nuclear power plant, Fukushima prefecture March 1, 2014. REUTERS Reuters

Muttonbirds in New Zealand that spend their winters off the coast of Japan may have been exposed to radiation coming from the Fukushima nuclear power plant. New Zealand scientists from the University of Auckland will check whether the radiation from Japan has entered the island nation's ecosystem.

Scientists fear that the Fukushima radiation may have reached New Zealand's food chain with the help of the birds. The damaged nuclear power plant and its radioactive content have loomed in Japan. The 2011 tsunami had destroyed the back-up generators of the plant that would have helped cool its nuclear fuel.

The overheating of the Fukushima plant had triggered meltdowns in three reactors and forced hundreds of thousands to leave their homes. Tens of thousands are still unable to return to areas contaminated with radiation.

The University of Auckland researchers will examine the feathers of the muttonbirds for any traces of gamma rays which indicate the presence of radioactive isotope cesium-134. They will collect feathers from South Island's prime muttonbird sites especially in Stewart Island.

Birds like New Zealand's sooty shearwaters migrate every year and often spend the summer mating and taking care of their young ones in New Zealand. The birds fly to the coast of Japan for the winter.

Dr David Krofcheck from the University of Auckland's physics department said the research was taking precautions since there was no evidence to indicate that the birds in New Zealand have become radioactive.

However, studying the birds' feathers for gamma rays will let scientists know if the birds had spent enough time in Japan's Fukushima plant to be exposed to cesium-124 from nuclear fission. If researchers do find significant levels of gamma rays, the next issue would be determining if the radiation has reached the food chain or local ecosystems.

The sooty shearwater of New Zealand is important to the Maori for its cultural and economic value. They harvest the nearly fledged chicks during muttonbird season. Dr Krofcheck has consulted with the Maori and the Rikiura Titi Islands Administering Body about the study.

The researchers will collaborate with Department of Zoology in the University of Otago. Previous tests regarding the exposure of muttonbirds to Fukushima's radiation had found no traces of cesium being passed to the birds' chicks.