As regular CFZ-watchers will know, for some time Corinna has been doing a column for Animals & Men and a regular segment on On The Track... particularly about out-of-place birds and rare vagrants. There seem to be more and more bird stories from all over the world hitting the news these days so, to make room for them all - and to give them all equal and worthy coverage - she has set up this new blog to cover all things feathery and Fortean.

Monday, 30 October 2017

Even modest oil exposure can harm coastal and marine birds

Date:  October 12, 2017
Source:  Wiley

Many birds and other wildlife die following an oil spill, but there are also other potential long-terms effects of oil exposure on animals. In a recent Environmental Toxicology and Chemistry study that examined blood samples from birds present in the Gulf of Mexico in 2010 and 2011 following the Deepwater Horizon oil spill, even birds with small amounts of oil present on their feathers experienced problems related to their red blood cells.

Helmeted hornbill, on verge of extinction, finds respite in new zone outside of known range

by Basten Gokkon on 23 October 2017

A recent survey has found a high concentration of near-extinct helmeted hornbills in a conservation area in western Borneo.

This “hornbill paradise” is currently not included in the IUCN range map for this particular species.

Conservationists have called for the map to be updated, for more research in the area, and for stronger law enforcement to protect the distinctive bird.

A conservation area in western Borneo holds an unexpectedly rich population of the helmeted hornbill, a bird driven close to extinction by poaching for its distinctive casqued beak, a field survey has found.

A research team from the conservation group Planet Indonesia recorded over 50 visual and audio detections of the hornbill during its yearlong survey in the protected area in northwestern Kalimantan, the Indonesian part of Borneo.

The discovery indicated a large concentration of the helmeted hornbill (Rhinoplax vigil), said Adam Miller, executive director of the NGO, in a statement.

While Borneo in general is known to be a habitat of the species, Miller pointed out that his team’s findings were the first to detect the bird’s presence in the protected region.

“When we found the helmeted hornbill … we could not believe it,” Miller wrote in a separate email. “We had not expected this rainforest to be so rich with hornbills.”

Stretching across 1,800 square kilometers (695 square miles) of forested area, the remote landscape covers three administrative districts and connects to a national park in Malaysia’s Sarawak state.

Other than the helmeted hornbill, Miller said, the region contains seven other hornbill species: the oriental pied hornbill (Anthracoceros albirostris), the bushy-crested hornbill (Anorrhinus galeritus), the wreathed hornbill (Rhyticeros undulatus), the black hornbill (Anthracoceros malayanus), the white-crowned hornbill (Berenicornis comatus), the rhinoceros hornbill (Buceros rhinoceros) and the wrinkled hornbill (Rhabdotorrhinus corrugatus).

“This landscape is indeed a hornbill paradise,” Miller said.

Migratory bird sighted 'for first time in Tamil Nadu'

TIRUPUR, OCTOBER 19, 2017 20:11 IST

Common Stonechat comes from central Asia and Europe, and Western Marsh Harrier from western Eurasia and Africa.

Two migratory bird species, Eurasian Marsh Harrier (also called Western Marsh Harrier) and Common Stonechat, have been sighted by a group of bird watchers, reportedly for the first time, near the S. Periyapalayam irrigation tank in Tirupur, Tamil Nadu.

“Common Stonechat is sighted for the first time in Tamil Nadu if one goes by records compiled by ornithologists,” said K. Ravindran, a regular bird watcher at the S. Periyapalayam tank for a decade.

Mr. Ravindran, who is also the president of the Nature Society of Tirupur, said that Eurasian Marsh Harrier was seen elsewhere in Tamil Nadu. Common Stonechat comes from central Asia and Europe, and Western Marsh Harrier from western Eurasia and Africa.

The Nature Society of Tirupur attributes a few possible reasons for the sudden appearance of these two birds here.

“Either they may have lost their way to places they usually visit, or because of the disturbances happened to their earlier habitats,” said Mr. Ravindran.

Sunday, 29 October 2017

Adelaide Symphony Orchestra to celebrate the song of the pied butcherbird in new composition

Posted Sat at 3:33am

The flute-like chirps of an iconic Australian songbird has inspired one of the nation's most prestigious orchestras.

The pied butcherbird, found in many backyards around the nation but best heard in the Australian outback, will perform — in a way — as part of the Adelaide Symphony Orchestra on Saturday night.

"It's such a spectacular singer, perhaps the world's finest songbird," said Hollis Taylor, a violinist and composer.

"It was my first trip to Australia and I found myself in the middle of three birds singing a trio; it was absolutely glorious, I had no idea that birds sang in trios.

"It changed my life, it was an epiphany."

For more than a decade, Ms Taylor has studied the melodies of the pied butcherbird, turning those songs into pieces of music.

This year, she has spent months travelling the MacDonnell Ranges near Alice Springs and Far North Queensland, creating a unique piece for the Adelaide Symphony Orchestra which incorporates her field recordings.

"I really tried to celebrate the birdsong rather than improve on it, and so almost always the instruments are playing the direct transcriptions," Ms Taylor said.

Fight to save dozens of seabirds trapped in plastic

Thomas Moore, Science Correspondent
Sky News20 October 2017

A painful death on 'plastic island'

Conservationists have mounted a rescue mission to save dozens of seabirds trapped in plastic and Sky News was given exclusive access to the operation.

The RSPB landed on Grassholm island, eight miles off the Pembrokeshire coast, to cut free young gannets from the fishing ropes and nets that adults use to build nests.

Greg Morgan, warden for the RSPB reserve, said there is so much fishing gear floating in the water around the island that the birds mistake it for the seaweed that they should be using.

He said: "We estimate there are 18 tonnes of plastic in the nests on the island.

"The chicks sit on the nest. As they turn, the plastic gets twisted around their leg and ensnares them.

"They should have flown away by now. Eventually the adults give up and they are left to starve."

We saw birds with plastic twine twisted so tight around their legs that it had cut through to the bone.

Other birds were already dead, their feet tethered to the nest by rope.


Declining baby songbirds need forests to survive drought

Date:  October 19, 2017
Source:  Virginia Tech

A new study aimed to identify characteristics that promote healthy wood thrush populations on US Department of Defense land.

Before cutting down forest, land managers in drought prone areas might first consider the birds in the trees.

According to a new study by biologists at Virginia Tech and the Smithsonian Migratory Bird Center, the offspring of a certain songbird, the wood thrush, are more likely to survive drought in larger forest plots that offer plenty of shade and resources.

These results were published Oct. 18 in The Auk: Ornithological Advances, a journal of the American Ornithological Society.

Wood thrush are common to the United States, but populations have declined by more than 60 percent since the 1960s. In addition, many species of songbirds, such as blue jays, robins, and cardinals, as well as wood thrush, face the highest risk of dying within the first five days of leaving their nests.

A team of Smithsonian biologists led by Brandt Ryder worked closely with Ben Vernasco, a doctoral candidate in biology at Virginia Tech, on a study that aimed to identify characteristics that promote healthy wood thrush populations on U.S. Department of Defense land. Vernasco specifically worked to determine the factors affecting wood thrush survival during the post-fledgling period -- the stage lasting about 21 days until baby birds become independent.

How many golden eagles are there?

Date:  October 18, 2017
Source:  American Ornithological Society Publications Office

For conservation to be effective, wildlife managers need to know how many individuals of a species are out there. When species are spread out over large areas and occur at low densities, this can be tricky. However, a new study applies an old technique called 'mark-recapture' in a novel way to count golden eagles, eliminating the need to actually capture and mark eagles with math that allows scientists to turn individual observations into population estimates.

Friday, 27 October 2017

Smart birds: Canada geese give hunters the slip by hiding out in Chicago

Date:  October 23, 2017
Source:  University of Illinois College of Agricultural, Consumer and Environmental Sciences

It's open season for Canada geese in Illinois from mid-October to mid-January. Unfortunately for hunters, Canada geese are finding a new way to stay out of the line of fire. Rather than being 'sitting ducks' in a rural pond, they're setting up residence in the city. Ornithologists conducted a recent study to try to find out why there were so many Canada geese in Chicago in the winter.

Birds without own brood help other birds with parenting, but not selflessly

October 23, 2017

Birds will sometimes care for the offspring of other birds of their own species if they anticipate future benefits. Being tolerated in another bird's territory and the chance to inherit that territory later are considered rewards for which some birds are willing to postpone their own chance of reproduction. On 23 October 2017 veni researcher Sjouke Kingma from the University of Groningen has published an article on this subject in Nature Communications.

In almost 10 percent of bird species around the world, certain individuals postpone their own chance of reproduction to help birds of the same species to care for their offspring. This behaviour has also been observed in certain mammals, fish and insects. Since the days of Charles Darwin, biologists have assumed that all creatures are selfish, and do everything they can to maximize the chance of passing their genes to their offspring. So why do some birds sacrifice themselves for the sake of others? What do they gain by not producing their own brood and wasting energy to help others?

One hypothesis is that they only help their relations, i.e. younger brothers and sisters with whom they share their genes. This is thought to be a way for the helpers to pass on their genes, without reproducing themselves. In a recent study, evolutionary biologist Sjouke Kingma refutes this widely accepted vision by showing that these individuals are also trying to improve their own future prospects. Kingma compared 44 species of birds, some of which help other birds while denying themselves their own brood. Although some birds only help family members, his research showed that a lot of birds are even more keen to help non-family members if they stand to inherit their territory in the future.

Reintroduced marsupials may pose new threat to ground–dwelling birds

23 October 2017

October 24, 2017

Native marsupials reintroduced in south-western Australia are a threat to ground-dwelling birds, a University of Queensland study has found.

Researcher Graham Fulton said ground-nesting and ground-dwelling birds had generally declined at a greater rate than other Australian bird groups, with the loss of eggs believed to be an important factor.

"We don't know a lot about the identity of ground-nest predators," he said.

Mr Fulton, a PhD student in the UQ School of Biological Sciences, said his research at Dryandra, south-east of Perth, highlighted the need for a greater understanding of the impacts of reintroducing native marsupials.

"Marsupials are not generally regarded as potential nest-predators of these birds, partly because the biology of rare Australian marsupials is not fully understood due to their rarity," he said.

The study found that three marsupials – boodie and woylie bettongs (Australian rat kangaroos) and brushtail possums (pictured right and left) – took eggs from artificial nests similar to those of the threatened painted button quail (pictured below right).

"Approximately one-third of the eggs were taken by the two bettongs and another third by brushtail possums," Mr Fulton said.

Geese-like birds seem to have survived the dinosaur extinction

By Jeff Hecht

They looked like loons but honked like geese, and are kin to a group of modern birds that includes ducks, geese and chickens. Meet the Vegaviidae, a newly named group of waterbirds that seemingly lived through the mass extinction that took out the dinosaurs.
Although the Vegaviidae are now extinct, they are the first bird group known to have survived the mass extinction, says Federico Agnolin at the Bernardino Rivadavia Argentine Museum of Natural Sciences in Buenos Aires.

At the end of the Cretaceous Period 66 million years ago, a mass extinction – probably caused by an asteroid impact – wiped out a swathe of species, including all non-avian dinosaurs. Birds survived the disaster, but which groups carried the flame has been unclear.
Bird fossils from the end-Cretaceous between 72 and 66 million years ago are few and fragmentary, says Joel Cracraftat the American Museum of Natural History in New York.

One of the few known species is Vegavis iaai, discovered on Vega Island off West Antarctica and described in 2005. Vegavis was a fish-eating diving bird that resembled a modern loon. However, Agnolin says its skeleton shows that it was related to ducks and geese, and to land fowl such as chickens.

Last year, palaeontologists described a second Vegavis fossil that included a syrinx, the bird version of vocal cords. They concluded that the birds honked like geese.

Thursday, 26 October 2017

Yellow-breasted Bunting at risk of extinction


BirdLife International is pushing an action plan to save the Endangered Yellow-breasted Bunting, after unchecked hunting has pushed it to the verge of extinction in the space of just three decades.

In the mid-1990s, the observed decline of Yellow-breasted Bunting in Hokkaido, Japan, alerted conservationists that this superabundant species might be in trouble. It has suffered a huge decline, possibly as much as 95 per cent of its population, in the span of just two to three decades. Prior to 2004, this attractive seed-eater was not regarded as of conservation concern, but since 2013 it has been listed as Endangered and this year the discussion on BirdLife’s Globally Threatened Birds Forum concerned a potential further uplisting to Critically Endangered.

The species migrates in huge flocks which are hunted in massive numbers, and its plight has been worsened by improvements in communication and transportation. The species gathers in large numbers at night to roost, making the birds easy to trap in high numbers. It is known as ‘Rice Bird’ in China, where it is hunted for food; this practice has been illegal since 1997 but continues on the black market to this day. 

'Lonely swan' reunited with flock at RSPB reserve

12 October 2017

An injured swan which was abandoned when its herd migrated to Iceland in March has been reunited with some of its former companions.

The whooper swan, named Hula, damaged a wing and was unable to join the annual 2,000-mile round trip from Frampton March Nature Reserve in Lincolnshire.

The cob has been waiting patiently for the other birds to return, staff at the centre said.

"The lonely swan is lonely no more," Chris Andrews, from the reserve, said.

"About 20 swans arrived back from Iceland this week and are spending their days eating sugar beet tops in nearby fields before returning to the reserve at night.

"Hula spotted two other whoopers close to the reserve and went over to join them," he said.
"Since then he seems to have spent a lot of time hanging out with them."

Mr Andrews said it is not known if they are simply friends or potential mates.

Whooper swans - so named because of the noise they make - migrate to breeding grounds in Iceland in the spring. A group of up to 60 return to the reserve each year for winter.

Mr Andrews said the others are expected to return over the next few days.

Britain's smallest bird finds sanctuary in gardens


The British Trust for Ornithology’s (BTO) Garden Bird Feeding Survey (GBFS) has revealed that a cold spell in late winter 2016-17 caused an influx of birds to feeders, including Goldcrests in particular.  

Winter 2016-17 was generally mild and garden feeders consequently quiet, but results from the GBFS found that more birds were making use of the supplementary food we put out during a cold snap in late January and early February. 

One of the species coming to British feeders in the colder weather was Goldcrest. In fact, Garden BirdWatchers have recorded high numbers of the species in gardens over the last two winters, with counts in February 2017 being 35 per cent higher than the average for the previous five years.

So far this year, it looks promising for another Goldcrest garden invasion, with high preliminary counts for September. Numbers of the species are severely affected by low winter temperatures, but the predominately mild winter weather of recent years might have helped to boost numbers.

New Zealand bird of the year: playful alpine parrot kea soars to victory

The world’s only mountain parrot whose cheeky antics divide Kiwis, beats kererū and kākāpō to coveted crown

Monday 23 October 2017 23.56 BSTLast modified on Tuesday 24 October 2017 00.52 BST

The kea, the world’s only alpine parrot, has been crowned New Zealand bird of the year, with thousands more votes cast for the species than there are surviving individuals.

New Zealand’s annual bird of the year competition hit new heights this year with more than 50,000 votes cast from around the country and the world. The competition is in its 13th year, and pits the country’s rare and endangered birds against one another. No bird has won twice.

The kea – a highly intelligent and inquisitive olive green mountain parrot that lives only in the Southern Alps – received 7,311 votes, streets ahead of the native wood pigeon, the kererū, which came second with 4,572 votes, followed by the kākāpō with 2,554 votes.

There are 168 bird species in New Zealand and about a third are threatened with extinction, with dozens more on the endangered list. Some species have dwindled to a few hundred individuals tucked away in isolated pockets of the country.

Wednesday, 25 October 2017

Not so cold duck? Man keeps looking for bird thought extinct

AP Science Writer
OCTOBER 23, 2017 8:34 AM

Hope is the thing with feathers, poet Emily Dickinson wrote. For Richard Thorns, the feathers are pink.

Thorns' hope? To prove that a colorful duck is not extinct. This week, he launches a seventh expedition into the inaccessible wilds of Myanmar to search for the pink-headed duck that hasn't been seen alive since 1949, and that was in India. No one has seen the bird alive in Myanmar in more than a century.

Thorns, a British writer who quit his shop clerk job 20 years ago after reading about the pink-headed duck in the book "Vanishing Birds," has spent $20,000 of his own money on previous fruitless trips. His birder brother called him mad.

"I could have had a lot of nice things," the 53-year-old said. "I don't want nice things. I want to see a pink-headed duck."

This time, he is backed by the Global Wildlife Conservation group, which launched a hunt for "lost species " — 25 quirky and elusive plants and animals beginning with the duck. A sports optic company and cheesemaking company are also helping pay.

Thorns and three others plan to head to the wetlands north of the vast Indawgyi Lake during the rainy season where they believe they have a better chance of spotting the duck. And Thorn thinks he has a secret weapon: elephants.

He used canoes in the past and thinks he probably spooked the shy birds. Now he plans to bring elephants stomping through the wetlands.

"Clearly a bird isn't going to hunker down if there are 2-ton elephants," said Thorn.

As crazy as it may seem, Thorns may be onto something, said ornithologist Kevin McGowan at Cornell University who isn't part of the expedition.

"Fairly regularly birds get rediscovered," says McGowan, who has gone on unsuccessful expeditions for the ivory-billed woodpecker. "We don't see all the world that is in front of our eyes."

New Peruvian bird species discovered by its song

Date:  October 23, 2017
Source:  Florida Museum of Natural History

Though found in 1996, this manakin wasn't discovered to be a new species until researchers listened to its song years later.
Credit: Andy Kratter/Florida Museum of Natural History

A new species of bird from the heart of Peru remained undetected for years until researchers identified it by its unique song.

In 1996, a group of Louisiana State University and Florida Museum of Natural History researchers traveled to the Cordillera Azul, an isolated mountain ridge in Peru, where they discovered a previously unknown manakin species.

With its bright yellow front feathers, the bird was different from the local subspecies of striped manakin, but nearly identical to the subspecies Machaeropterus regulus aureopectus found in the distant Venezuelan tepuis. But it has a completely different voice.
The newly discovered manakin's song lacks undertones and has a one-noted rising vocalization, rather than two-noted falling vocalization with undertones or a falling monosyllabic vocalization with undertones.

It was given the name Machaeropterus eckelberryi, commemorating the 20th century bird illustrator Don Eckelberry.

Andy Kratter, a museum ornithology collection manager, said the differences went unnoticed for years because the research team didn't have vocalizations for all of the bird species.


British obsession with feeding birds is making their beaks grow longer, scientists believe

Sarah Knapton, science editor 
19 OCTOBER 2017 • 7:00PM

The British obsession for feeding birds is causing their beaks to grow longer so they can reach into bird feeders, scientists suspect. In an extraordinary example of rapid evolution, researchers have discovered that the UK tit has a beak up to 0.3mm longer than its European counterparts.

Although it sounds like a tiny difference, scientists believe even such a small advantage could aid survival, ensuring those with longer beaks live long enough to lay eggs, and pass on their genes.

Researchers at Oxford University have been studying the Wytham Woods great tit population in Oxfordshire for 70 years and recently spotted that British great tits’ beaks have been getting longer since the 1970s.

Scientists at Oxford also teamed up with researchers from Sheffield University, the University of East Anglia and Dutch experts to also examine whether genes have changed to allow for the longer beaks. They found significant differences in the DNA of British tits compared with those in the Netherlands.

Grassland sparrows constantly searching for a nicer home

Date:  October 11, 2017
Source:  American Ornithological Society Publications Office

Some birds regularly move to new territories between years, depending on factors including habitat quality and the presence of predators, but what about within a single breeding season? Grassland ecosystems are particularly dynamic, continuously shaped by fire and grazing, and a new study confirms that one particular grassland bird moves frequently each summer in search of the best territories. For grasshopper sparrows, the grass really does look greener on the other side.

DNA tests on albatross excrement reveal secret diet of top predator

Date:  October 18, 2017
Source:  University of Tasmania - Institute for Marine and Antarctic Studies

A study that used DNA tests to analyse the scats of one of the world's most numerous albatrosses has revealed surprising results about the top predator's diet. DNA analysis of 1460 scats from breeding sites around the Southern Ocean has shown that the diet of black-browed albatrosses contains a much higher proportion of jellyfish than previously thought.

Japan’s anime-loving penguin Grape-kun passes away at Tobu Zoo

The cardboard cut-out he fell in love with was moved from the enclosure to be with the penguin as he passed away.

In April this year, a Humboldt penguin called Grape-kun stole our hearts when he appeared to develop feelings for a cardboard cut-out of an anthropomorphic penguin from the Japanese hit anime Kemono Friends.

The character, called Hululu, was placed in the penguin enclosure at Tobu Zoo in Saitama Prefecture as part of a limited-time promotion for the anime, which saw other anthropomorphised animal characters from the series scattered throughout other areas of the zoo as well.

While the other animals paid no attention to the cardboard cutouts in their midst, Grape-kun became so enamoured by his 2-D visitor that he couldn’t tear his eyes away from her, and it wasn’t long before photos began surfacing online, showing the penguin staring up at her for hours at a time and refusing to leave her side.

Monday, 23 October 2017

Museums Worcestershire: How flightless parrot reached Worcester

15th October

Sometimes referred to as an Owl Parrot due to its moon-like face, the bird is nocturnal and entirely vegetarian, feeding mainly on flowers, roots and leaves.

While our specimen is slightly faded in colour, the Kakapo is usually a bright mossy green with dappled yellow and black.

This camouflage allows the Kakapo some protection against birds who hunt above the forest using sight, but is of little use against mammals who hunt using smell. Before the arrival of humans the Kakapo was common throughout New Zealand’s forests, but became vulnerable to attack from introduced species such as rats and cats. The bird is now heavily monitored and managed on predator-free islands.

This specimen is believed to have travelled to the museum in the latter half of the 19th century, although its precise history is uncertain. Worcester had become a lively centre for natural history research and learning by this period, with the founding of the Worcestershire Natural History Society and other dedicated groups creating and promoting their own collections.

Turns Out One of World's Rarest Songbirds Never Actually Existed

6 OCT 2017

In a truly fascinating case, scientists have discovered that what was once thought to be an extremely rare, elusive songbird in Africa, may have never existed after all.

For more than 30 years, experts tried to catch a glimpse of a bird so evasive it was deemed almost mythical. And now DNA analysis points to an explanation for these frustrating efforts, and it's bad news for the bird's entire species.

This weird story starts with a family of brightly-coloured, medium-sized songbirds that tweet all across Africa and Asia. Collectively known as bulbuls and greenbuls, they comprise approximately 130 species.

One of those species is a yellowish-green bird called the icterine greenbul (Phyllastrephus icterinus), a cute forest-dweller common across the entire western and central Africa.

Introducing self-resetting traps to protect endangered birds in Mauritius

6 Oct 2017

By Jean Hugues Gardenne and Obaka Torto

Improving the efficiency of rat control is vital to protect the critically endangered Mauritius Olive White-eye (Zosterops chloronothos) and sustain its population in the Black River Gorges National Park. In line with BirdLife International’s global conservation strategy to Save Species, BirdLife’s Partner in Mauritius, the Mauritian Wildlife Foundation has introduced the use of self-resetting traps to preserve the highly endangered bird endemic to Mauritius.

Zosterops chloronothos.jpegThe Mauritius Olive White-eye is estimated to have an extremely small population that continues to decline rapidly due to predation by mammals such as rats that have been introduced in their habitats. The species also has a very small range as  its habitat is declining in quality and extent. It feeds on nectar, fruit and insects, and travels considerable distances to feed on nutritious flowers. The species has long been protected by law and the Black River Gorges National Park partly covers the species’ distribution.

Sunday, 22 October 2017

New 48 MILLION-YEAR-OLD bird discovered in Germany with ‘likely relation to hoopoes’

A NEW 48 million-year-old species of bird has been discovered in Germany that is a “likely relation to modern hoopoes”, according to experts.

PUBLISHED: 05:02, Wed, Oct 18, 2017 | UPDATED: 05:58, Wed, Oct 18, 2017

Fossils have been discovered of a 48 million-year-old bird

Fossils were discovered of the 48 million-year-old bird that is similar in size to a wren and uses waxy oils to clean its feathers.

The author of the study, Dr Shane O’Reilly, said: “This research shows these long-beaked tiny birds, about the size of a wren, are likely the ancestors of modern hoopoes and wood-hoopoes.

“The Messelirrisoridae birds probably spent most of their lives in trees, rather than foraging on the ground or catching insects in flight.

“The uropygial gland, also called the preen gland, is an important gland in modern birds that produces a waxy oil that is transferred to feathers during preening.

Extinction worry for Africa’s largest eagle species


Polemaetus bellicosus -Masai Mara-8.jpgThe population of Africa’s largest eagle species is in freefall in South Africa and may be edging towards extinction, according to a new UCT study.

Martial eagle sightings have dropped by as much as 60% since the late 1980s, in stark contrast to human population growth across their shared natural habitat, the study published this week in the scientific journal Bird Conservation International found.

Although the exact reasons for the decline remains unclear, researchers say their findings point to an urgent need to better understand the threats to the bird.

The study also highlighted a decline in Martial eagle sightings within protected areas, including the Kruger National Park and the Kalahari Gemsbok National Park.

However, declining numbers of the species in protected areas were not as severe as elsewhere, suggesting that these areas could act to limit the factors leading to the sharp decline.

Dr Arjun Amar and PhD student Danië* Cloete from UCT’s FitzPatrick Institute of African Ornithology conducted the study using two Southern African Bird Atlas Project surveys carried out 20 years apart. 

Their previous research showed that comparing these surveys provided an accurate way of measuring changes in the population size of this species.

Martial eagle total population figures are still relatively inexact, but their conservation status was uplisted in 2013 from Near Threatened to Vulnerable - which means they are recognised to be globally threatened.