New Zealand bird outwits alien predators

Jun 04, 2008

New research published in this week's PLoS ONE, led by Dr Melanie Massaro and Dr Jim Briskie at the University of Canterbury, which found that the New Zealand bellbird is capable of changing its nesting behaviour to protect itself from predators, could be good news for island birds around the world at risk of extinction.

The introduction of predatory mammals such as rats, cats and stoats to oceanic islands has led to the extinction of many endemic island birds, and exotic predators continue to threaten the survival of 25 percent of all endangered bird species worldwide.

Dr Massaro says the impact of exotic predators on the native birds of oceanic islands is particularly profound as they evolved over millions of years largely in the absence of these predators and appear naïve towards newly introduced mammals.

But their study on the bellbird, an endemic New Zealand bird, has identified the ability of a previously naïve island bird to change its nesting behaviour in response to the introduction of a large suite of exotic mammalian predators by humans.

Bellbirds were studied at three sites with varying levels of predation risk: a mainland site with exotic predators present (high risk); a mainland site with exotic predators experimentally removed (recent low risk); and an offshore island where exotic predators have never been introduced (permanent low risk).

It was found that females spent more time on the nest per incubating bout with increased risk of predation, a strategy that minimised activity at the nest and decreased the risk of an exotic predator locating and destroying the eggs.

"Parental activity during the nestling period, measured as number of feeding visits per hour, also decreased with increasing nest predation risk across sites, which would further reduce the risk of an exotic predator destroying the nest," Dr Massaro said.

"It shows that such species are not necessarily trapped by their evolutionary history as is generally considered to be the case but they, in fact, have the ability to change their behaviours in ways that appear adaptive.

"More importantly, this study demonstrates that such a change can occur over an ecologically relevant time-scale of years and not centuries."

Drs Massaro and Briskie say although their research was done on New Zealand birds, the conclusions are applicable worldwide. They believe conservation efforts towards the survival of other island birds could be more effective if advantage was taken of the ability of island birds to respond to exotic predators, especially when the elimination of such predators is not possible.

Citation: Massaro M, Starling-Windhof A, Briskie JV, Martin TE (2008) Introduced Mammalian Predators Induce Behavioural Changes in Parental Care in an Endemic New Zealand Bird. PLoS ONE 3(6): e2331. doi:10.1371/journal.pone.0002331

Source: Public Library of Science

Explore further: Genetic study tackles mystery of slow plant domestications

add to favorites email to friend print save as pdf

Related Stories

Japan snail sheds tail to escape, scientist finds

Oct 03, 2012

Snails that can shed their tails to escape much faster-moving predators and then regrow the amputated body section have been discovered living in sub-tropical Japan, a study said Wednesday.

The spiralling cost of invasive species

Aug 28, 2012

Some aliens arrived as stowaways. Others were brought in deliberately, for fun or profit. And others were so tiny that nobody noticed them until way too late.

Where birds fly offers clues to man

May 11, 2011

Each December a hardy flock of birdwatchers scatters across Mecklenburg County in North Carolina for the National Audubon Society's Christmas Bird Count, which has tracked bird movements for more than a century.

Recommended for you

Plants with dormant seeds give rise to more species

10 hours ago

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Researchers successfully clone adult human stem cells

14 hours ago

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

User comments : 0

More news stories

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

Male monkey filmed caring for dying mate (w/ Video)

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

Researchers develop new model of cellular movement

(Phys.org) —Cell movement plays an important role in a host of biological functions from embryonic development to repairing wounded tissue. It also enables cancer cells to break free from their sites of ...

Impact glass stores biodata for millions of years

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...