A parasite attack on Darwin’s finches means they’re losing their lovesong



A Small Tree Finch from the Galápagos Islands with an enlarged nostril caused by a parasite.
Katharina J Peters, Author provided

Katharina J. Peters, Flinders University and Sonia Kleindorfer, Flinders University

A parasite known to infect beaks in some iconic Darwin finches on the Galapagos Islands is changing the mating song of male birds.

Our research, published today in Proceedings of the Royal Society B, reveals how the parasite deforms the beak. This has the effect of weakening the male bird’s mating call, and making it no longer clearly distinguishable from that of other closely related species.

A changed song can have an important effect on the male finch’s ability to find a mate.




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It’s another factor that could contribute to declining numbers of these already threatened birds on the Pacific archipelago, about 1,000km off the coast of South America.

A family song to impress

A male finch learns the mating song from his father, and produces the same song for the rest of his life.

It’s a simple tune consisting of one syllable repeated 3 to 15 times, depending on what species of finch he belongs to. Larger-bodied finch species produce a slower song with few syllable repeats, and smaller-bodied finch species produce faster song with many syllable repeats.

Whatever species of finch you belong to, hitting the high notes is important – because females prefer males who can produce such vocally challenging songs.

In the case of the Medium Tree Finch (Camarhynchus pauper), a critically endangered species that only occurs on Floreana Island of the Galapagos Islands, its species-typical song has a bright resonance that rings across the forest canopy.

Medium Tree Finch.
Author provided35.5 KB (download)

An accomplished male singer that can hit the high notes is quickly swooped up by a female looking to pair with a proficient singer.

The ‘Vampire’ parasite

The Vampire Fly – a suggested name for the parasite Philornis downsi given its blood feeding habits from dusk until dawn – was first discovered in a Darwin’s finch nest in 1997.

The parasitic Philornis larvae in a finch nest.
Sonia Kleindorfer, Author provided

Since then, the devastating impacts of its larval feeding habits on nestling birds have been coming to light. The adult fly is vegetarian, but the females lay their eggs into bird nests and their larvae feed on nestling bird beaks from the inside out.

Many Darwin’s finch species now have beaks with massively enlarged nostrils because of damage the feeding fly larvae have caused during the nestling stage. We discovered that a changed beak apparatus measurably affects the song of Darwin’s tree finches with consequences for pairing success.

A Medium Tree Finch male with extremely enlarged nostrils is unable to hit the high notes.

Medium Tree Finch with enlarged nostrils.
Author provided32.2 KB (download)

We found the same pattern in Small Tree Finches (C. parvulus) with enlarged nostrils.

Male finches that produce song with a narrower frequency bandwidth, because their song has a lower maximum frequency, have poor quality song. These males are less likely to be chosen by females, a pattern we documented in both the Medium Tree Finch and the Small Tree Finch.

Also, the song of Medium Tree Finches with enlarged nostrils sounds like the song of the Small Tree Finch.

Small Tree Finches.
Author provided29 KB (download)

When species merge

But confusion among the species and their mating songs may not necessarily be a bad thing for the future survival of individual finches – though it could herald the collapse of species lineages.

Previously, we discovered evidence of hybridisation in Darwin finches. This is where two separate species of finch breed which could potentially produce a new species, phase out one of the species, or cause the collapse of the two existing species into one.

We observed hybridisation driven by female Medium Tree Finches pairing with male Small Tree Finches.

When a female Medium Tree Finch inspects male Small Tree Finches in the forest, she pairs with one who produces high quality song, even if that male is from another species.

A Tree Finch with a normal beak and nostril size, so no infection from the parasite.
Katharina J Peters, Author provided

This female choice seems to be paying dividends, because hybrid pairs with greater genetic diversity also sustained fewer of the parasitic larvae in the nest. And that could lead to fewer birds with infected beaks.




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There are concerted efforts underway to develop control and eradication methods for P. downsi on the Galapagos Islands, building on a collaborative relationship between the Charles Darwin Foundation and the Galapagos National Parks. The Philornis downsi Action Group is an international consortium of concerned scientists working to develop biological control methods.

Our new research is an important step towards understanding how this invasive fly may be changing the evolutionary pathway of Darwin’s finches by literally changing the beak of the finch.The Conversation

Katharina J. Peters, Postdoctoral fellow, Flinders University and Sonia Kleindorfer, Professor of Animal Behaviour, Flinders University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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How we’re helping the western ground parrot survive climate change



A western ground parrot being released with a GPS tracker fitted.
Alan Danks

Shaun Molloy, Edith Cowan University and Robert Davis, Edith Cowan University

When a threatened species is found only in one small area, conservationists often move some individuals to another suitable habitat. This practice, called “translocation”, makes the whole species less vulnerable to threats.

In the past, this approach has worked really well for some species, but climate change is creating new problems. Will the climate change at that location in the future, and will it remain suitable for the species of interest? On the other hand, some regions might become appropriate for a threatened species.

This fundamental question is important in a rapidly changing climate, yet it has seldom featured when picking new areas for translocations.

Western ground parrots live and nest on the ground, making them very vulnerable to foxes and cats.
Alan Danks/DBCA

Saving the western ground parrot

Our recent research applied climate change modelling to translocation decisions for the critically endangered western ground parrot. This species is now restricted to a single population, with probably fewer than 150 birds, on the south coast of Western Australia.

It is enigmatic, in that it lives and nests entirely on the ground, unlike almost all other parrots except the closely related night parrot. And it is one of the many unique animals that make Australia so distinctive from all other parts of the world. But living on the ground has its drawbacks, as the parrot is very vulnerable to foxes and cats.

Its home near the south coast is particularly vulnerable to the effects of climate change. As southwestern Australia becomes warmer and drier, the risk of fire to the parrot increases.

Understanding potential climate change impacts is essential when selecting reintroduction sites. We developed high-precision species distribution models and used these to investigate the effect of climate change on current and historical distributions, and identify locations that will remain, or become, suitable habitat in the future.

Our findings predict that some of the western ground parrot’s former south coast range will become increasingly unsuitable in the future, so reintroductions there may not be a good idea. Four out of 13 potential release sites are likely to become inhospitable to these threatened birds.

On the other hand, many of the former or future sites are likely to become important refuge habitats as the climate continues to warm, and would make an excellent choice for any translocations or reintroductions.

We have given this information to an expert panel, who will use these predictions identify and prioritise areas for management and translocation.

Researchers have radio tracked a small number of birds to learn more about habitat use and movement patterns.
Allan Burbidge

The parrot in the coal mine

Fire is already a significant threat which, combined with predation by feral cats, may have led to the loss of this species from its former home at Fitzgerald River National Park. Many of these threats act together, so they must all be considered and managed alongside climate change.

What’s more, the western ground parrot may be an important indicator for the fate of many other species it currently (or formerly) shares its range with. These include the western whipbird, noisy scrub-bird, and a carnivorous marsupial, the dibbler.

These species are all likely to face the same threats and may be equally affected by the changing climate. Future studies will attempt to model these species and to assess whether all will benefit from similar management.

Many challenges remain for the western ground parrot, including the possible negative genetic impacts of the current small population size, and the increasing risk of damaging fires in a drying and warming climate.

But locating “future-proofed” sites is giving us some hope we can ensure the long term persistence of this enigmatic species, and the myriad other unusual species that occur in the biodiversity hotspot of southwestern Australia.


The authors would like to thank Allan Burbidge and Sarah Comer from the WA Department of Biodiversity Conservation and Attractions for their invaluable help and guidance in putting together this article.The Conversation

Shaun Molloy, Associate research scientist (Ecology), Edith Cowan University and Robert Davis, Senior Lecturer in Vertebrate Biology, Edith Cowan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Adani’s finch plan is approved, just weeks after being sent back to the drawing board


Stephen Garnett, Charles Darwin University; Brendan Wintle, University of Melbourne; David Lindenmayer, Australian National University; Don Franklin, Charles Darwin University, and John Woinarski, Charles Darwin University

The Queensland government has ticked off a crucial environmental approval for Adani’s Carmichael coalmine, bringing the contentious project a step closer to becoming reality.

It has approved Adani’s proposed management plan for the endangered black-throated finch, less than a month after the state’s environment department announced a delay in approval because the plan was judged to be inadequate.




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Four days after the May 18 federal election, in which the mine’s future was a prominent issue, Queensland Premier Annastacia Palaszczuk called for an end to the delays and uncertainty.

In a statement issued today, the government said it has now approved a “strengthened” version of the plan, submitted by Adani earlier this week.

Under the revised plan, Adani has now committed to:

  • “establish enhanced understanding” of the finch, with the help of “appropriate population studies”

  • implement “appropriate monitoring protocols” to track the finch’s population over time

  • restrict grazing in nearby areas.

The only remaining state environmental approval for the project now is Adani’s groundwater management plan, on which a decision is due by June 13.

Bad plan caused the delays

As members of the scientific panel that reviewed the finch management plan, we can understand the Premier’s frustration. There is no excuse for such a poor plan to have been put forward for approval when the company has been aware for almost a decade that the land it wants to mine is home to the largest known remaining population of the black-throated finch.

There has already been ample time to undertake the studies Adani has pledged to carry out in the future. Had it done so before now, it could have put its claims to be able to manage the finch’s extinction risk on a much more solid footing.

As it is, the plan we reviewed made biologically improbable assumptions about the finch, while ignoring what is known about the finch’s precipitous decline so far. Under the plan, people with the curious title of “fauna spotter-catchers” were to find finches and move them “to suitable habitat adjacent to the disturbance, if practical” before the habitat is destroyed.

It sounds impractical, and will in all likelihood prove to be so. If the adjacent habitat already has finches, it is likely to be “full” and so won’t be able to support mining refugees. If it lacks finches, there is probably a very good reason.

The finch has been observed only a handful of times in just a tiny proportion of the area purchased for conservation purposes near the mine site. The finch has had more than 10,000 years to occupy and breed in the proposed conservation area that is supposed to offset the impact of the mine. It hasn’t, and it probably won’t.

As far as can be determined by overlaying the available maps, the proposed conservation area has a different geology and soil type. Adani has categorically failed to provide robust scientific evidence to demonstrate that the conservation reserve will adequately offset the loss of the finches and the habitat in the mined area. It has had more than 10 years to conduct the science to provide the evidence.



Meanwhile, before the existing habitat is mined, the plan had talked about grazing being used to control bushfire fuel loads and reduce the abundance of a weed called buffel grass. Yet grazing is thought to be the main reason the finches have disappeared from most of their once vast range – they once occurred from the Atherton tablelands to northern New South Wales.

The new plan is said to “restrict grazing” but no details are yet available. Under the original plan, the cattle would have got fat on the buffel grass pastures just as they did in all the places where the finch once lived.

Rigorous research

What must really frustrate the Queensland Premier is the contrast between Adani’s efforts with the black-throated finch and the much more rigorous work done by mining companies who find themselves in similar situations. Rio Tinto, for example, is currently funding high-quality research on two other birds, the palm cockatoo and red goshawk, ahead of its planned expansion of bauxite operations on Cape York Peninsula.

Vista Gold, meanwhile, funded research on stress levels in Gouldian finches long before mining was planned to begin at its Mt Todd goldmine in the Northern Territory.

In criticising Adani’s plan, we are not criticising mining. Like all Australians, we use the products of mining every day. We enjoy a high standard of living that is delivered partly by royalties from mining. We also understand that miners (and politicians) in Queensland want to see jobs created.

Most mining companies, however, provide jobs while willingly abiding by national and state legislation. They compromise where necessary to minimise environmental harm. And crucially, they commission research to demonstrate how they can mitigate damage well before that damage occurs, rather than when their operations are already underway.




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In contrast, the so-called research and monitoring that went into Adani’s finch plan seems only to conclude that more research is needed. After nine years, Adani did not even know the population size of the finch, how it moves around the landscape, or even what it eats.

Given the time available, this bird could (and should) have been among the best-studied in Australia. The management plan could then have been based on robust evidence that would show how best to safeguard the finch population.

Now the research and monitoring is a hurried add-on with no proof that the threat posed to the finch can actually be solved and an extinction averted. Given the high stakes involved, Australians might reasonably have expected something altogether more rigorous.The Conversation

Stephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin University; Brendan Wintle, Professor Conservation Ecology, University of Melbourne; David Lindenmayer, Professor, The Fenner School of Environment and Society, Australian National University; Don Franklin, Adjunct Research Fellow, Research Institute for Environment and Livelihoods, Charles Darwin University, and John Woinarski, Professor (conservation biology), Charles Darwin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why Adani’s finch plan was rejected, and what comes next



The black-throated finch is on the verge of extinction.
Brian McCauley/flickr, CC BY-NC

Samantha Hepburn, Deakin University and April Reside, The University of Queensland

Adani’s plan to manage an endangered finch was rejected last week by the Queensland government, stalling progress on the Carmichael mine.

The mine would cover much of the best remaining habitat for the endangered black-throated finch. The Queensland government required Adani to commit to gathering more accurate finch population data, limit the cattle grazing in the finch conservation area and determine food availability throughout the year, before they could approve the plan.

The rejection is one of two outstanding environmental approvals required before Adani can commence work on the mine. The second is the plan to manage groundwater-dependent ecosystems, which the Queensland government has yet to come to a decision on.




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The federal government has been reported as “already approving” the finch plan. But legally, the Queensland government must determine whether the plan complies with the conditions of the environmental authority and, under the bilateral framework, the federal government must give due regard to this assessment.

What’s wrong with Adani’s plan?

Last Friday Queensland’s Department of Environment and Science decided not to approve Adani’s black-throated finch management plan because it does not fulfil certain basic requirements.

The decision is based on a detailed report from an independent expert panel.

The black-throated finch is on the verge of extinction, one of 238 threatened Australian birds.

The black-throated finch is experiencing habitat loss and degradation.
Steve Dew/flickr, CC BY



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The greatest threat to the black-throated finch is habitat loss: it has disappeared from over 80% of its original range. Strong protection, and careful management, of its remaining habitat is crucial.

The finch, once found across north-eastern Australia, is now largely found on Moray Downs and surrounding properties, north-west of Clermont in central Queensland. A core part of the habitat is within the 28,000 hectare (ha) footprint of the Carmichael mine, where there are far more black finches than elsewhere due to the intact woodlands and a history of minimal livestock grazing.

It is expected the mines will disturb 50,977 ha of black-throated finch habitat, and that 34,156 ha will be completely cleared.

A total of 87 square kilometres of habitat will be destroyed through the creation of open pits, and a further 61 square kilometres may be degraded beyond repair due to the influence of underground mining on groundwater.

After habitat loss, the second greatest threat to the finch is cattle grazing, which destroys the grass seeds they need to survive. Yet Adani’s management plan for the black-throated finch involved grazing cattle on areas that are supposed to be devoted to conservation of the finch.

Instead of establishing a finch conservation reserve, the Adani plan proposed what was in effect a paddock. Providing a species management plan that effectively conserves finch habitat is a core condition of Adani’s mining licence.

State vs federal priorities

The Queensland government’s rejection of the plan brings into stark focus some of the problems with the existing environmental assessment framework.

The Adani plan includes cattle grazing, despite the threat to finch habitats.
Shutterstock

The environmental authority for the mining licence was approved by the Federal government. The environmental management plan for the finch did not, however, address core impact concerns. And yet this is the very reason that the plan was required from the outset. The inadequacies of the plan only became apparent because of the oversight of the Queensland government.

The federal government has not been proactive despite’s its mandate under our National environment act – the Environmental Protection Biodiversity Conservation act. In fact, a recent analysis found the federal government has approved hundreds of projects to clear black-throated finch habitat over the last 18 years.




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There are clearly differences in priorities regarding the environment between a federal Liberal and a state Labor government. However, environmental assessment can only be effective if is not undermined by political agendas, and is grounded in scientific rigour and scrutiny.

A one-stop shop

At the federal level, any project likely to have a “significant impact” on a matter protected by the Environment Protection and Biodiversity Conservation Act must be referred to the federal environment minister.

If the minister decides the project impacts a matter of national environmental significance, he or she will then determine how to assess that project at the national level. Legislated options include: an environmental impact statement, a public environment report and public inquiry.

The federal government has entered into bilateral agreements with all state and territory governments. As a result, rather than the state and federal governments conducting separate assessment, the aim is to promote a single, focused environmental evaluation.

The Queensland government has entered into a bilateral assessment agreement with the Commonwealth government for Adani’s coal project, which effectively allows it to make an environmental assessment that the Commonwealth Minister will then take account of when deciding whether to grant approval.

This means that both the Queensland and the federal government are involved in the approval and assessment process environmental authorities and conditions, one of those being the management plan for the black-throated finch. In order to optimise outcomes they need to work together collaboratively.

Where to next?

The rejection means that Adani will now need to submit a new or revised plan that addresses the Queensland government’s concerns. In particular, Adani will need to limit cattle grazing in the conservation area, and gather more information regarding the availability of seed throughout the year.

This may take time but is critical, because in its current form, the plan does not meet the legal requirements for the Environmental Authority, which means that it cannot be approved at the state level.

Without state approval the Adani coal mine cannot proceed. The Queensland government has rigorously assessed Adani’s management plan by commissioning a report by an independent expert panel and then acting on the advice of this report.

This robust approach is crucial to the whole framework of environmental assessment. Genuine commitment to protecting endangered species and managing vital groundwater resources is vital if we want to reverse Australia’s dire trajectory of environmental decline.The Conversation

Samantha Hepburn, Director of the Centre for Energy and Natural Resources Law, Deakin Law School, Deakin University and April Reside, Researcher, Centre for Biodiversity and Conservation Science, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Pet Cassowary Kills Owner


The link below is to a news report of a Cassowary killing its owner in the USA.

For more visit:
https://www.theguardian.com/us-news/2019/apr/14/cassowary-attack-giant-bird-kills-owner-in-florida-after-he-fell