DRONES V HUMANS

Eagle catching a drone
Eagle catching a drone
Raptors are being trained to snatch drones out of the sky. Photo ©Shutterstock

Who won the ‘epic birdwatching test’?

To anyone who has witnessed the impact drones can have on birds, the following research from South Australia might be ‘disturbing’.

A group of scientists at the University of Adelaide have pitted humans and drones in a so-called ‘epic test of birdwatching’ – and the drones came out on top. Or did they?

Ecologist Jarrod Hodgson is reported in WIRED as having used thousands of fake birds to test whether drone-based bird counters are better than professional birdwatchers at tracking numbers

Plastic terns

The birders were asked to count a large number of plastic terns on a beach, from a distance typical for birdwatching. The researchers flew an off-the-shelf quadcopter 30 to 120 m above ground to photograph the fake birds – using a digital camera with the time-lapse function activated.

Later, people with little birdwatching experience counted the birds in the photos—and they were 43% – 96% more accurate than the experts on the ground. (Hardly surprising.)

“We consider [the results] are especially relevant to aggregating birds, including seabirds like albatrosses, surface nesting penguins and frigate-birds, as well as colonial nesting waterbirds like pelicans,” says Hodgson.

“Even when the animals themselves can’t be seen, their nests or tracks can provide reliable indicators of their presence.”

Serious side-effects

But as is often the case when science and nature clash, there are potentially serious side-effects to be considered.

Seeing a huge flock of roosting shorebirds spooked by a raptor flying overhead is ‘natural’ and the birds know how to cope with that threat. But when some idiot tourist with a duty-free drone repeatedly sends it out into a resting or feeding flock, the reaction is chaotic, frenzied and quite clearly more disturbing.

A study published in the journalCell in 2015 found that drone fly-bys raised the heart rate of black bears in Minnesota, and eagles have been known to attack drones in the wild.

Hodgson says, “The results of such research will help to refine and improve drone monitoring protocols so that drones have minimal to non-existent impact on wildlife.”

Let’s hope so.

©Tony Neilson 2018

Bird flock spooked by a predator
Shorebirds choose easy-exit beaches when roosting at high tide. Photo ©Tony Neilson

A SOUND SOLUTION

Black-tailed godwits in flight
Huge flock of migrating waders
New early warning system could reduce building collisions. Photo: ©Tony Neilson

‘Acoustic lighthouse’ warning system for birds

Following on from our recent posts about the mortal danger man-made structures pose to birds in flight, there is fresh hope from the world of science.

Hundreds of millions of birds die every year as a result of collision with tall structures such as skyscrapers and wind turbines.

So-called ‘bird friendly’ materials including ceramic frit patterns on glass, shutters and screens can help reduce the carnage.

Potentially more exciting, however, is trial technology called the ‘acoustic lighthouse’.

Revealed something

John Swaddle from the College of William and Mary, Williamsburg, VA revealed something of the new experimental research at this month’s (February) American Association for Advancement of Science (AAAS) annual meeting.

Swaddle says one of the reasons birds crash into buildings is that their vision is largely directed toward the ground and to the side while flying. “They have evolved to use navigation and foraging cues on the ground and their eyes are placed more to the sides of their skulls than in humans.

Black-tailed godwits in flight
Birds don’t look where they are going in flight. Photo: ©Tony Neilson

Texting while driving

“In other words, they aren’t looking where they are going, somewhat like someone texting while driving.”

The research group’s acoustic lighthouse idea would project a conspicuous sound out in front of a structure. “The novelty of the sound will attract the visual attention of a flying bird and increase the chances it will take evasive action,” he says.

And tests with captive birds indicate it works. “Birds slowed their flight speed twice as much, altered their flight posture to enable greater maneuverability, and some even avoided the structure when exposed to the acoustic lighthouse.”

Commercialisation of the acoustic lighthouse is expected to follow successful field trials.

Natural Images 2018

THE INVISIBLE KILLER

New glass window technology illustration
Sandpiper flock in flight
Glass windows take out billions of birds every year. Photo ©Tony Neilson

‘Smart’ windows may reduce bird carnage

It is almost impossible to comprehend the impact that windows have on birds.

According to the US Fish and Wildlife Service, 750 million birds die each year as a result of collisions with glass-clad buildings. Other research available on Google suggests the global annual glass-related death rate could exceed a billion.

Sadly, that still doesn’t compare to the devastation caused by free-ranging cats, which the American Bird Conservancy estimates at 2.4 billion annually in the US alone. (Birdlife Australia recently reported the figure for Australia at around 365 million – a million per day.)

Slow acceptance

Architects and developers are slowly accepting that they should be building more ‘bird-friendly’ structures – using new glass technologies such as ceramic frit patterns, UV coatings, shutters and screens.

But there is still a big gap between a building being ‘bird-friendly’ and one that is totally ‘bird-safe’.

New glass window technology illustration
Concept illustration showing ‘darkening’ effect of glass made with perovskites. Photo: Science

To put things in perspective, think about the last time you were at someone’s place and almost walked straight into a closed glass door – probably on the way inside from the deck or balcony. (I know I’ve done it – with glass in hand.)

The fact is that plain glass is invisible to humans – and to birds. We learn from (hard) experience and visual clues that it is not something to walk through, but birds don’t get those signals. Most birds’ first encounter with glass is their last.

New smart windows

I mention all this because there is something very new on the horizon that has strong energy-generating potential and might also make windows more obvious to birds (the latter being more a personal hope than a fact).

Science magazine reported in January on amazing new smart windows that can darken the sun and also generate electricity. They use a family of crystalline materials called perovskites.

Transforming windows

The magazine says perovskites can transform windows, keeping them clear on cold days, but turning them dark in the hot summer sun.  ‘Two research groups report that they’ve created perovskite-tinted windows that not only transition based on the temperature, but also harvest power like solar cells. The new technology could one day help cool buildings by shading out sunlight and generating power to boot.’

Although darken/lighten products have been around for some time, perovskites offer a possible route to smart windows and solar windows at the same time.

PIGEON ‘WHISTLES’ DANGER WITH FEATHERS

Pair of crested pigeons at waterhole, dusk
Pair of crested pigeons at waterhole, dusk
Crested pigeons show off their ‘gem’ colours in evening light, Bowra. Photo: ©Tony Neilson

Australia’s indigenous crested pigeon (Ochyphaps lophotes) is in the scientific spotlight – because it has developed the ability to ‘whistle’ with its feathers.

According to a recent report in Current Biology the bird is able to signal alarm with specifically modified wing feathers.

Researchers used video and feather-removal experiments to demonstrate that the highly modified 8th primary wing feather (P8) produces a distinct note during each downstroke.

Note changes

When crested pigeons flap their wings to take off, the upstroke of each beat produces a 1.3-kilohertz low note, and the downstroke produces a 2.9-kilohertz high note.

The study group found that the noise came from the eighth feather on the pigeon’s wing – and the high note disappeared when that feather was removed. But when the feather was placed in a wind tunnel, the high-frequency sound returned.

Bird reaction

To see how other birds reacted to the noise, the researchers played audio recordings of slow and fast wing beats to pigeons in their natural habitat.

During the slow beats, the birds stayed where they were. But the faster wing beats set the birds fleeing. It seems these ‘wing whistles’ are serving as a type of warning signal – based on the speed of the cycle.

EXTINCTION OF THE NATURAL EXPERIENCE

Condor, Taronga Zoo, Sydney
Condor, Taronga Zoo, Sydney
The death of ‘experience’ spells yet another danger for global wildlife. Photo: ©Tony Neilson

Young people losing touch with outdoors

‘The average Australian child spends less time being active outdoors than a maximum security prisoner.’

That has to be the most ‘arresting’ opening sentence of all time.

The shock finding is at the core of new research by Queensland-based ecologists Danielle Shanahan and Richard Fuller.

‘The Extinction of Experience’ is a global phenomenon based on the notion that, for most humans, their experience of nature has been extinguished.

Only over-45s understand

In southeast Queensland where Shanahan and Fuller’s Research Council-funded project is focused, it is clear that understanding of nature is much higher in people over 45 than those under that age.

In a 2016 Wildlife Australia article, the ecologists say their work and that of others at the University of Queensland is part of a growing international study of a declining experience of nature, and what that means for people and conservation.

The implication is that people who don’t experience nature for themselves are unlikely to value it.

Faster recovery

Shanahan and Fuller say evidence is mounting that an extinction of nature experience is also detrimental for people’s health and wellbeing. They cite faster recovery from surgery for hospital patients with a view of trees, and reduced cardio-vascular death rate for people living near green spaces.

However,  when it comes to motivating conservation, they say the importance of experiences with nature and the psychology behind it are not well understood. “But it makes intuitive sense. As Robert Pyle said back in 1978, what is the extinction of the condor [above] to a child who has never seen a wren?”

THE BIRD HUNTER IN NORTH KOREA

Miranda Wetland manager Keith Woodley portrait
Keith Woodley – part of the Kiwi contingent with entree to North Korea. Photo: ©Tony Neilson

Keith Woodley is one of very few foreigners to have been beyond the barriers to North Korea to see what’s happening with their wading birds.

For that alone, the New Zealander is a deserving new member of the Natural Images Conservation Champions Club.

We interviewed the tall, be-whiskered manager of the Pukorokoro Miranda Shorebird Centre near Auckland about his trips to the DPRK in search of some of the world’s missing waders.

He also loosened up about his involvement in unravelling the mysteries of the East Asian-Australasian wader flyway, corrupt developers and politicians in South Korea, his outstanding Godwits – Long-haul Champions book, and a few other surprising things.

The interview – including rare images from North Korea – will be posted in two parts, starting before our April e-news is due. So keep checking the website.

WHEREFORE ART THOU, RED GOSHAWK

Mature male red goshawk keeping watch near a nest
Mature male red goshawk keeping watch near a nest
The richly marked male red goshawk is much smaller and half the weight of the female. Photo: ©Tony Neilson

Satellite tracking of endangered raptor a partial success

Natural Images has been wondering what happened to the critically endangered red goshawks involved in what the Queensland Government has described as a ‘world first’ satellite-based study of this rare and elusive raptor.

We have received reports from birding experts familiar with the Cape York-based project that the study birds – including a mature female fitted with a transmitter – may have perished.

Natural Images approached the Queensland Department of Environment and Heritage Protection (DEHP) for comment on the Rio Tinto-sponsored tracking project to find out more about the elusive raptor, and the news is a mix of good and bad.

A DEHP spokesperson confirmed in mid-February that two of the birds had been ‘bow netted’ for the study: an adult female (pictured below) caught in September 2015 and a fledgling female from the same nest in January 2016. Both were captured in the Weipa region of Cape York.

GPS satellite transmitters were attached to both birds via a ‘backpack’ harness.

Scientists with transmitter-carrying red goshawk
Queensland EHP scientists and a Rio Tinto representative with a female red goshawk netted near Weipa. Photo: EHP

So where are they now? The DEHP spokesperson says the transmitter on the adult female “failed due to technical issues” after being tracked for three months. But the movements of the juvenile female are still being tracked after more than 12 months.

Whether or not the adult bird is still alive is anyone’s guess, but the department says understanding the movements of the red goshawk in relation to their surroundings is “vital to developing management actions suitable to protect them”.

Adults range wide area

Preliminary results indicate an adult home-range of nearly 300 square km, and that juveniles can disperse as far as 370 km from the nest.

Young red goshawk with parent at nest
The female ‘chick’ (left) is already much bigger than her father. Photo: ©Tony Neilson

The DEHP says more birds need to be tracked before suitable management actions can be developed. “But the study has already succeeded in proving the efficacy of this tracking technique, opening the door to a previously [unaffordable] understanding of this spectacular, highly secretive threatened bird.”

Surveillance of the younger bird is scheduled to end in January 2018 when her transmitter harness deliberately ‘degrades’ and falls off.

The red goshawk is a large, reddish-brown hawk with strongly streaked and barred plumage, massive yellow legs and feet, and a slight crest. The male is about 50 cm long and weighs about half that of the 60 cm female.

Email: tonywneilson@icloud.com

©Natural Images 2017