Quantcast
Environmental News for a Healthier Planet and Life

Love Triangles Kill, at Least for Swift Parrots

Animals
Love Triangles Kill, at Least for Swift Parrots
Swift parrot. Dejan Stojanovic / ANU

Tasmania's swift parrots can't catch a break. Logging has reduced their preferred blue gum breeding habitat by a third in the past 20 years. Sugar gliders, a kind of nocturnal possum introduced in the 1800s, are gobbling up female parrots at an alarming rate. And now, The Guardian reported Tuesday, scientists have found that the skewed male-to-female ratio is changing the mating habits of the endangered species in a way that puts its survival further at risk.


As the female population has declined to the point where there is only one female for every three male parrots, the excess males have begun to bother already-paired females for sex, distracting both parents from mating and raising young. In a study published in The Journal of Animal Ecology on Monday, researchers at Australian National University (ANU) found that more than half of swift parrot nests now had babies from more than one father.

"This is remarkable for parrots because most species are monogamous," lead researcher Prof. Rob Heinsohn said in an ANU press release.

The shared parenting isn't working out for the babies, however. While equal numbers of eggs are being laid, fewer are living to leave the nest, Heinsohn told The Guardian. That's because the breeding male parrot ends up spending all his time fighting off unattached males and the female spends her time dealing with the harassment and sneaking sex with the interlopers.

"We think the females are having sex with the other males for a range of reasons, but probably the main one is just to get them off their backs," Heinsohn said in the press release.

Both parents have less time, then, to gather food for their offspring.

"Although most population decline was directly attributable to sugar gliders killing nesting females, the impact of conflict and lower success from shared mating reduced the population by a further five percent," Heinsohn said in the press release.

The researchers calculated that if the lowest observed rate of shared paternity persisted for three generations, the birds' population would decline by 89.4 percent.

Sugar gliders are an especial threat to female parrots because they can enter hollow nests and kill females while they are incubating their eggs there. They kill off more than half of the female swift parrots in Tasmania every year.

A sugar glider Jonathan Hornung / CC BY-SA 2.5

Study co-author Dejan Stojanovic told The Guardian that scientists were working with the Tasmanian government to control the sugar glider population and installing nesting-boxes for the parrots that lock when the sun sets at night, but nothing had been done about deforestation.

"I am not confident at all [that the species will survive]," Stojanovic told The Guardian. "We have been working on swift parrots for the last decade, we know so much about them, even to the point that we know about their sex lives now … but even though we know so much, we are actively logging their habitat. We are wilfully pushing the things that are going to lead to their extinction."

Ningaloo Reef near Exmouth on April 2, 2012 in Western Australia. James D. Morgan / Getty Images News

By Dana M Bergstrom, Euan Ritchie, Lesley Hughes and Michael Depledge

In 1992, 1,700 scientists warned that human beings and the natural world were "on a collision course." Seventeen years later, scientists described planetary boundaries within which humans and other life could have a "safe space to operate." These are environmental thresholds, such as the amount of carbon dioxide in the atmosphere and changes in land use.

Read More Show Less

EcoWatch Daily Newsletter

A 3-hour special film by EarthxTV calls for protection of the Amazon and its indigenous populations. EarthxTV.org

To save the planet, we must save the Amazon rainforest. To save the rainforest, we must save its indigenous peoples. And to do that, we must demarcate their land.

Read More Show Less

Trending

UN Secretary General Antonio Guterres delivers a video speech at the high-level meeting of the 46th session of the United Nations Human Rights Council UNHRC in Geneva, Switzerland on Feb. 22, 2021. Xinhua / Zhang Cheng via Getty Images

By Anke Rasper

"Today's interim report from the UNFCCC is a red alert for our planet," said UN Secretary General Antonio Guterres.

The report, released Friday, looks at the national climate efforts of 75 states that have already submitted their updated "nationally determined contributions," or NDCs. The countries included in the report are responsible for about 30% of the world's global greenhouse gas emissions.

Read More Show Less
New Delhi's smog is particularly thick, increasing the risk of vehicle accidents. SAJJAD HUSSAIN / AFP via Getty Images

India's New Delhi has been called the "world air pollution capital" for its high concentrations of particulate matter that make it harder for its residents to breathe and see. But one thing has puzzled scientists, according to The Guardian. Why does New Delhi see more blinding smogs than other polluted Asian cities, such as Beijing?

Read More Show Less
A bridge over the Delaware river connects New Hope, Pennsylvania with Lambertville, New Jersey. Richard T. Nowitz / Getty Images

In a historic move, the Delaware River Basin Commission (DRBC) voted Thursday to ban hydraulic fracking in the region. The ban was supported by all four basin states — New Jersey, Delaware, Pennsylvania and New York — putting a permanent end to hydraulic fracking for natural gas along the 13,539-square-mile basin, The Philadelphia Inquirer reported.

Read More Show Less