Plant hormone boost for New Zealand’s critically endangered night parrot

The flightless, nocturnal and sweet-smelling kākāpō was thought to be extinct, but during the 1970s, two remnant populations were discovered. One, in Fiordland, included only males.
From Wikimedia Commons, CC BY-ND

Janet Pitman, Victoria University of Wellington

New Zealand’s nocturnal and flightless parrot, the kākāpō, may be famous for trying to mate with the head of biologist Mark Carwardine, but this unique species is facing some serious challenges.

With fewer than 160 birds alive, kākāpō are critically endangered. One reason for their dwindling numbers is that they only breed every few years, when native trees produce masses of edible fruit or seeds.

Our research suggests that the birds’ breeding success depends on oestrogen-like hormones (phytoestrogens) found in these native plants.

Kākāpō are so rare that each bird has its own name. Sirocco was hand-reared as a chick and has become accustomed to people.

Hormone boost from plants

Our study included kākāpō (Strigops habroptilus) and two other New Zealand native parrots, the endangered kākā (Nestor meridionalis) and kea (Nestor notabilis). All three have infrequent breeding success.

Kākāpō in particular have a low reproductive rate and together with the kākā, only breed successfully every three or four years, during mast years, when mass fruiting of native trees occurs.

2016 was a mast year and a record breeding season for kākāpō – the best since New Zealand’s Department of Conservation began managing and monitoring the night parrots 25 years ago.

This link between the parrots’ successful breeding and high levels of fruiting in native plants has focused our investigations on potential stimulants present in their food plants that might activate or improve reproduction.

One hypothesis is that steroid-like compounds in the fruits of certain native plants provide a trigger for breeding. It proposes that kākāpō don’t produce enough of the hormone oestrogen to make a fertile egg, but by eating these fruits and the phytoestrogens they contain, the birds supplement their own hormone levels.

The native rimu tree produces a lot of berry fruit during mast years every two to four years.
Veronika Meduna, CC BY-ND

This increases the production of egg yolk protein, which in turn leads to eggs that have a better chance of being fertilised successfully.

We know from other studies that kākāpō seek out the fruit from the native rimu tree (Dacrycarpus cupressinum) during mast years. We believe that this is how kākāpō get extra oestrogen from their diet, and that rimu and other native plants provide a hormone boost that is key to kākāpō reproduction.

A kākāpō chick, newly hatched.
Andrew Digby / NZ Department of Conservation, CC BY-ND

Parrots more sensitive to oestrogen

In our current study, conducted by PhD graduate Dr Catherine Davis, we examined the receptivity of New Zealand and Australian parrots to a range of steroid compounds, including oestrogens, and compared it to those of other birds.

We tested various native plant species for oestrogenic content and we found that indeed there is a high amount of phytoestrogens in some of New Zealand’s native plants.

We then looked at the receptivity of parrots to this plant hormone. We studied the genetic makeup of the receptor that is activated by oestrogens in kākāpō, kea, kākā, kākāriki, the Australian cockatiel, and compared this with those in the chicken.

We found that the parrots’ oestrogen receptor was different. All of the parrot species have a unique sequence in the receptor gene, which may make them more sensitive to oestrogen, compared to other bird species, or humans.

In parrots, this receptor contains an extra eight amino acids in the region that binds the hormone.

Most kākāpō live on Codfish Island, a predator-free sanctuary island at the southern end of New Zealand. The Department of Conservation checks the birds regularly, particularly during breeding seasons.
Veronika Meduna, CC BY-ND

Increasing fertility

By adding this amino acid sequence to a computer modelling programme based on the human oestrogen receptor, we have shown that this difference in the parrot-specific receptor would change the strength with which it binds to the oestrogen hormone.

The down-stream effects of this may be an increased sensitivity to plant oestrogens in parrots. This research supports the notion that the parrots’ oestrogen receptor responds differently to oestrogenic compounds in native trees in New Zealand during mast years.

We have previously confirmed the presence of oestrogenic activity in key compounds present in rimu and tōtara (Podocarpus totara), as well as extracts from a number of New Zealand plant species that kākāpō are known to graze. However, the chemical structures of the oestrogenic materials of most New Zealand native plants are not known.

The question remains why the rate of successful breeding of kākāpō in mast years is lower than that of other parrot species. The identification of plant chemicals capable of binding to the parrot oestrogen receptor together with information about plant grazing behaviours of parrots may provide new insights into the conservation of the species that are in decline.

With further research, we are hoping to identify the specific compound in native plants that elicits these oestrogenic properties. This information may enable us to synthesise this compound in the lab. It could then be administered in some way to increase the fertility of our native parrots.

Janet Pitman, Senior Lecturer in Reproductive Biology and Biotechnology, Victoria University of Wellington

This article was originally published on The Conversation. Read the original article.

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Bigfoot, the Kraken and night parrots: searching for the mythical or mysterious

In 2012 scientists succeeded in filming for the first time ever a giant squid in its natural habitat.
EPA/NHK/NEP/DISCOVERY CHANNEL/AAP

Euan Ritchie, Deakin University

It’s remarkable how little we know about Earth. How many species do we share this planet with? We don’t know, but estimates vary from millions to a trillion. In some respects we know more about the Moon, Mars and Venus than we do about the ocean’s depths and the vast sea floors.

But humans are inquisitive creatures, and we’re driven to explore. Chasing mythical or mysterious animals grabs media headlines and spurs debates, but it can also lead to remarkable discoveries.

The recent photographing of a live night parrot in Western Australia brought much joy. These enigmatic nocturnal birds have been only sporadically sighted over decades.

Another Australian species that inspires dedicated searchers is the Tasmanian tiger, or thylacine. A new hunt is under way, not in Tasmania but in Queensland’s vast wilderness region of Cape York.

This is the first photograph of a live night parrot, taken in Western Australia in March 2017.
Bruce Greatwitch

Other plans are afoot to search for the long-beaked echidna in Western Australia’s Kimberley region.

In the case of the thylacine, old accounts from the region that sound very much like descriptions of the species raise the prospect that perhaps Cape York isn’t such a bad place to look after all.

But in reality, and tragically, it’s very unlikely that either of these species still survives in Australia. For some species there is scientific research that estimates just how improbable such an event would be; in the case of thylacines, one model suggests the odds are 1 in 1.6 trillion.

Chasing myths

The study and pursuit of “hidden” animals, thought to be extinct or fictitious, is often called cryptozoology. The word itself invites scorn – notorious examples include the search for Bigfoot, the Loch Ness Monster or Victoria’s legendary black panthers.

The search for Bigfoot is an extreme case of cryptozoology.

Granted, it’s probably apt to describe those searches as wild goose chases, but we must also acknowledge that genuine species – often quite sizeable ones – have been discovered.

Remarkable discoveries of animals thought to be fantasies or long extinct include giant squid, mountain gorillas, okapi, Komodo dragons and coelacanths.

In some cases, like the giant squid, these animals have been dismissed as legends. The reclusive oarfish, for example, are thought to be the inspiration for centuries of stories about sea serpents.

Oarfish can grow up to 8 metres long and swim vertically through the water. Commonly inhabiting the deep ocean, they occasionally come to shallow water for unknown reasons.
AAP Image/ Coastal Otago District Office

Technology to the rescue

Finding rare and cryptic species is self-evidently challenging, but rapid advances in technology open up amazing possibilities. Camera traps now provide us with regular selfies of once highly elusive snow leopards, and could equally be used with other difficult-to-find animals.

Candid camera, snow leopards in the Himalayas.

Environmental DNA is allowing us to detect species otherwise difficult to observe. Animal DNA found in the blood of leeches has uncovered rare and endangered mammals, meaning these and other much maligned blood-sucking parasites could be powerful biodiversity survey tools.

Acoustic recording devices can be left in areas for extended time periods, allowing us to eavesdrop on ecosystems and look out for sounds that might indicate otherwise hidden biological treasures. And coupling drones with thermal sensors and high resolution cameras means we can now take an eagle eye to remote and challenging environments.

Drones are opening up amazing possibilities for biological survey and wildlife conservation.

The benefits of exploration and lessons learned

It’s easy to criticise the pursuit of the unlikely, but “miracles” can and do occur, sometimes on our doorstep. The discovery of the ancient Wollemi pine is a case in point. Even if we don’t find what we’re after, we may still benefit from what we learn along the way.

I’ve often wondered how many more species might be revealed to us if scientists invested more time in carefully listening to, recording and following up on the knowledge of Indigenous, farming, and other communities who have long and intimate associations with the land and sea.

Such an approach, combined with the deployment of new technologies, could create a boom of biological discovery.

Euan Ritchie, Senior Lecturer in Ecology, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University

This article was originally published on The Conversation. Read the original article.

Still here: Night Parrot rediscovery in WA raises questions for mining

Robert Davis, Edith Cowan University

The Night Parrot is unquestionably one of Australia’s most enigmatic, elusive and enthralling species. The final frontier of Australian ornithology, this cryptic parrot eluded dedicated expeditions to find it for nearly half a century.

Last week, a momentous chapter in the Night Parrot story was written, with the first photograph of a live Night Parrot in Western Australia. The photos come in the wake of several other recent sightings, including the parrot’s rediscovery in Queensland in 2013.

Despite media reports, the parrot has never been officially listed as extinct, with sporadic evidence of its existence throughout the 20th century.

But now we know for sure that the parrots are alive and found across the continent, we can move on to making sure they remain so in the future.

Mystery bird

We know that Night Parrots favour spinifex or tussock grasslands, often close to inland wetland systems. But the areas of potential habitat are vast throughout inland Australia.

The Night Parrot has been listed as endangered in the Action Plan for Australian Birds since 1992. It is listed as endangered under federal legislation.

It has never been listed as “presumed extinct” or “extinct”. Reliable ongoing reports and the well-known cryptic nature of the species meant that the ornithological community considered it likely to have survived, albeit incredibly hard to spot.

The Night Parrot has been known to exist in WA since at least 2005, when a colleague and I clinched the first peer-accepted sighting in recent Australian history during an environmental impact assessment for the Fortescue Metals Group (FMG) Cloudbreak mine.

Fortescue Marshes, where the Night Parrot was first seen again in WA in 2005.
Robert Davis

This was by no means the first sighting of Night Parrots in WA, with regular and reliable reports since at least the 1980s. But until 2005 none had provided sufficient detail to eliminate other possibilities. Further sightings have been monitored at another location in the arid zone since 2009 and that work is pending publication.

The significance of the latest find is immense. A dedicated team of birdwatchers (Adrian Boyle, Bruce Greatwich, Nigel Jackett and George Swann) has confirmed the existence of a population in WA. The discovery, resulting from a well-planned expedition, is the start of a real dialogue about Night Parrot conservation in WA.

The latest record cements the fact that Night Parrots are present at several locations in WA and potentially throughout arid Australia, including in regions rich in mineral resources.

In contrast to the Queensland populations, which have so far been found in national parks and pastoral leases, the WA situation sets up a quandary for how to manage development, Night Parrots and mining.

Mining and conservation

Our 2005 sighting was important because, given the parrot’s endangered status, FMG was required to provide offsets for potential disturbance to Night Parrot habitat. The offsets included avoiding areas of likely habitat on the Fortescue Marshes, and funding follow-up surveys throughout the areas surrounding the proposed mine. These unfortunately did not find further evidence of Night Parrots.

Research offsets from FMG also funded the writing of a national research plan for Night Parrots. This was later followed by on-ground research on Night Parrots at Pullen Pullen Reserve in Queensland, the population found by naturalist John Young in 2013.

Recent developments by other WA resource companies have seldom considered Night Parrots. My personal experience is that surveys usually look for endangered mammals such as Northern Quolls and Bilbies, but rarely search properly for Night Parrots. This is likely due to two main reasons.

The first is the incredibly cryptic nature of the Night Parrot. Clearly the species has evaded detection for so long because it is difficult to find.

The second is what I term “the Thylacine factor”. The only equivalent species in Australia that has the same degree of scepticism and mythology is the Thylacine.

Thylacines have (so far) not been rediscovered. But developers, consultants and regulators take the same attitude to Night Parrot sightings. The parrots are often seen as a mythical animal that doesn’t exist. The idea of looking for them is met with mirth.

Finding the parrots

Recent findings from research by Steve Murphy in Queensland, and other recent work in WA, are slowly providing us with the tools to overcome both of these issues. With better knowledge of their specific habitat requirements, including a need for long-unburned grasslands close to water sources, we can reduce the daunting challenge of Night Parrots potentially existing anywhere that spinifex is found.

Fire is one of the threats facing the Night Parrot.
Robert Davis

The recent release of calls from the Queensland population and a new recording of calls from the WA population provide the most powerful tool yet for doing surveys. Playing back the calls can be used to elicit a response from any Night Parrots in the area. The call can also be used to identify calls from deployed remote recording devices.

As more populations are discovered and more evidence becomes available, this will help convince the public and decision-makers that the parrots are (hopefully) found across a wide range and need careful management, despite the difficulty of observing them.

Let’s hope government bodies will strongly enforce the requirement to search for Night Parrots in all areas of potential habitat within their known current and historic range. This should ensure that we don’t lose any parrots before they are even found.

Robert Davis, Senior Lecturer in Vertebrate Biology, Edith Cowan University

This article was originally published on The Conversation. Read the original article.

Cracked it! A 30-year cold case involving an egg and the mysterious Night Parrot

Leo Joseph, CSIRO; Jeremy Austin, University of Adelaide, and Penny Olsen, Australian National University

Sometimes nature leaves little clues that can be difficult to interpret, so getting things right isn’t always easy.

Consider the case of an egg that was found in northern Australia’s remote Tanami Desert. It was spotted abandoned on the ground among spinifex in the early 1980s.

After being studied by ornithologists, the view was that it may well be an egg of the spinifex-nesting Night Parrot, described by the Smithsonian as one of the world’s most mysterious birds. The chances of finding such a rarity are astronomical.

The bird’s scientific name is Pezoporus occidentalis and it is known in that part of the Northern Territory as Yurrupudpudpa by the local indigenous group, the Eastern Warlpiri.

But was this really the egg of a Night Parrot? There are no confirmed Night Parrot eggs among the extensive collections of the world, so nobody was really sure.

Nevertheless, the possibility drifted loosely into the literature that it was the only known egg of the Night Parrot.

A remarkable bird

The Night Parrot – as the name suggests – is a truly nocturnal parrot, and the only other one is the Kakapo of New Zealand.

This bird of the Australian outback is also extraordinarily elusive, known from fewer than 30 specimens scattered through the world’s museums, despite its range stretching all the way from the Pilbara to northwestern Victoria.

In 2013, the parrot was “rediscovered” after its almost complete disappearance in the early 20th century and despite considerable efforts to prove it was still around.

Naturalist John Young found a tiny population alive and seemingly well, if not in great numbers, in remote western Queensland.

Since then, research has yielded plenty of information about what the birds need for their conservation and management.

So what then of the fate of the Tanami egg find?

For 30 years the egg sat unstudied, first in the South Australian Museum and then in the Museum and Art Gallery of the Northern Territory, under accession code T2614.

Finally, a team led by one of us (Penny) decided to investigate further, with the results published today in Australian Field Ornithology.

An actual egg of the Night Parrot would be a great prize – not least because knowing of a place where Night Parrots could be shown to have bred would be a useful piece in a jigsaw of the bird’s biology that was still wildly incomplete.

Extracting the DNA

Penny contacted Jeremy Austin at the Australian Centre for Ancient DNA at the University of Adelaide. The plan was to extract DNA from dried membranes inside the egg to obtain a DNA sequence that could verify the egg’s origin.

If a DNA sequence could be obtained, then it could be compared with sequences from two Night Parrot specimens that had both been found dead, incredibly enough, in western Queensland in 1990 and 2006. These are lodged in the collection of the Queensland Museum.

It was a simple but good plan, perhaps a little technically exacting to execute, but Jeremy’s expertise carried the day. A DNA sequence was obtained from the mystery egg.

On entering it into databases of DNA sequences of the world’s birds and with a figurative as well as literal holding of breath, the researchers waited for the result.

The DNA sequence turned out to be an excellent match for … a Brown Quail (Synoicus ypsilophorus).

It’s an ex-parrot egg

It was nowhere near a match for the Night Parrot, or indeed any other parrot.

This may have settled the matter, but not quite. Apart from being a rather interesting record of the Brown Quail, one more angle needed pursuing. That was a visit to egg collections held in the research collections of museums, specifically that of the CSIRO’s Australian National Wildlife Collection (ANWC), in Canberra.

The ANWC egg collection has a number of clutches of eggs of Brown Quail as well as several of one of the Night Parrot’s closest relatives, the Eastern Ground Parrot (Pezoporus wallicus).

Eggs (top, left) from the Crested Pigeon from near Mt Hopeless in South Australia and (top, centre) the Eastern Ground Parrot, near Noosa in Queensland and (top, right) near Evans Head in New South Wales. Eggs from the Brown Quail (bottom, left) at Bruny Island in Tasmania and (bottom, left) from near Orange in New South Wales.
Australian National Wildlife Collection, Author provided

The Eastern Ground Parrot, though a different and better-known species, is an ecological and evolutionary equivalent of the Night Parrot but found in coastal heaths. The point is that they are indeed a very closely related species, so their eggs can reasonably be expected to be similar.

All the world’s parrots lay eggs that are white – bleached sand white – and somewhat rounded, not pointed, at one end like a chicken’s egg tends to be.

The egg found in the Tanami Desert was indeed pale, though not bleached sand white, and it was pointed at one end. A scan through the ANWC collection showed that some clutches of Brown Quail eggs are rather pale and whitish but that they never attain that bleached whiteness of a parrot egg. Typically, they are variably speckled brown.

And the shapes of Brown Quail and parrot eggs differ markedly. One end of the quail’s egg is always pointed, just like the Tanami egg.

The value of collections

Though we may with hindsight ponder why the Tanami egg was ever thought to be of a parrot, let alone a Night Parrot, the story is a salutary lesson in the value of research collections held in museums.

They provide the material from which DNA can be extracted and sequenced to build up molecular-level descriptions of the world’s biodiversity. They provide us with robust understanding of what the species of the world and their eggs (or larvae or fruits or seed heads) look like.

Museums are a major repository of the raw data with which we study how life on earth has evolved. Along the way, they can also provide us with answers to tantalising mysteries about rare and little known species.

As for the mysterious Night Parrot, the search goes on for new populations and more details of this elusive bird.

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Dr Steve Murphy, who is studying the Night Parrot population in western Queensland, co-authored this article.

Leo Joseph, Research Director and Curator, Australian National Wildlife Collection, CSIRO, Canberra, CSIRO; Jeremy Austin, Deputy Director and ARC Future Fellow, Australian Centre for Ancient DNA, University of Adelaide, and Penny Olsen, Honorary Professor in the Division of Evolution, Ecology and Genetics, Australian National University

This article was originally published on The Conversation. Read the original article.

Australia: Saving the Night Parrot

Australia: More on the Night Parrot

The link below is to an article with more news on the elusive Night Parrot.

For more visit:
http://www.australiangeographic.com.au/journal/mysterious-night-parrot-caught-on-film.htm

Australia: Queensland – Night Parrot Found Again

The link below is to an article reporting on the rediscovery of the Night Parrot in western Queensland, Australia.

For more visit:
http://www.australiangeographic.com.au/journal/night-parrot-seen-alive-again-after-30-years.htm