Feed aggregator

Not your average starling. Nathan Rupert/Flickr, CC BY-NC-ND

Encountering a snake in the wild is many people’s worst nightmare. So imagine walking through the dense tropical forests of north Queensland and stumbling across an aggregation of 15 hungry snakes loitering beneath a giant canopy tree.

You’re probably wondering why the snakes are there? The answer is that the tree above is laden with hundreds (sometimes thousands) of bird nests; a colony of metallic starlings (Aplonis metallica).

And it’s not just snakes. For the past three years I have been studying these colonies as part of a PhD program at the University of Sydney. Our paper describing this remarkable ecological phenomenon has just been published in PLoS ONE.

In a single year, I recorded more than 100,000 animals (representing 42 species) beneath starling colony trees.

Annual bonanza

These aggregations are tiny (with an average of 140 square metres). They therefore represent one of the most dense and species-rich animal groupings on Earth. Many of the species encountered beneath the starling colonies are 1,000 times more abundant there than beneath otherwise similar trees in the surrounding landscape.

The hosts of this annual animal extravaganza are small, glossy-black birds with bright red eyes (the metallic starlings). In reality, we know little about them.

Existing literature suggests they migrate to northern Queensland from New Guinea each year, although it is possible that some stay in Australia year-round. The starlings begin nesting in November, and we think they raise three broods of young before nesting ceases at the beginning of April. Starlings return to the same trees every year (I know of one tree active for at least 15 years), and the trees they use are remarkably unique.

Most trees used by starlings are poison-dart trees (Antiaris toxicaria; the same species Asian peoples used to dip the tips of their poison darts). The significance of the tree’s toxicity to the starlings is unknown, but they are tall (emergent from the surrounding canopy), with smooth bark, and are isolated from nearby vegetation.

Through climbing experiments, we found that starlings likely actively seek out these trees to minimise nest predation by snakes (in most cases, snakes cannot climb the tree trunks).

The area directly beneath the colonies is similarly unique. The ground is covered by seeds and guano dropped by the thousands of starlings above, and the smell is extraordinarily pungent. The massive surge of nutrients dropped at these sites, together with mechanical disturbance by visiting animals, kills the surrounding vegetation such that the colonies form a barren moonscape in stark contrast to the dense forest just metres away.

Rainforest menagerie

I stumbled across my first Cape York starling colony when I was 14 years old. Despite the large number of snakes using the tree, I initially took the system for granted – the snakes are there to eat the birds – that seemed straightforward enough.

It wasn’t until I described the system to Rick Shine at the University of Sydney that we decided to investigate the colonies in more details, as part of my PhD program. To do this, I located 28 trees in the rainforests at the northern tip of Cape York, which I’ve been surveying for the last three years.

Nightly surveys with a head-torch regularly revealed enormous numbers of scrub pythons (Morelia amethistina), brown tree snakes (Boiga irregularis), cane toads (Rhinella marina), giant tree frogs (Litoria infrafrenata), small mammals (such as Melomys capensis) and centipedes. Those animals aggregate to feed on fallen starling chicks, massive numbers of invertebrates, and seeds dropped by the starlings.

To survey for day-time visitors, I primarily used infrared camera traps. Sifting through the first set of photos was mind-blowing. Nearly every photograph showed more than 30 feral pigs or scrub turkeys (Alectura lathami), as well as more “exotic” species such as noisy pittas (Pitta versicolour) and palm cockatoos (Probosciger aterrimus). The latter species is meant to be rare, but we sometimes found 10 individuals in a single photograph.

We even recorded three specimens of a giant blue-tailed monitor lizard never previously recorded from the Australian continent (Varanus doreanus).

There is little doubt that these seasonal gatherings of animals are a unique part of Australia’s natural heritage. Animal aggregations captivate people’s imaginations, and there are few places on earth where so many different species come together to utilise such a massive nutrient subsidy.

Remarkably, this system remained undescribed until now, offering yet-another reminder of the scientific importance and sheer awesomeness of the Australian tropics.

Daniel Natusch received funding for this research from the Skyrail Rainforest Foundation, the Holsworth Wildlife Endowment, and the Australian Research Council.

I read about the butterfly decline noticed by people all around the country, described by Patrick Barkham (Record low UK butterfly count is ‘a shock and mystery’, 10 October). I don’t find it so much of a mystery, having spent the summer planning for and walking from the Royal Botanical Gardens in Edinburgh on what we called a Bee Line.

This initiative was triggered by a visit in September 2014 to our former farm on the edge of Salisbury Plain. When we moved there in the late 1940s, there were permanent pastures, hedges and ancient drove roads lined with wayfarers’ trees and carpeted with wildflowers – orchids, harebells, trefoils – and abuzz with bees, butterflies, dragonflies and pollinators of all kinds. Now, 60 years on, it is a silent landscape; no cows, chickens, sheep, or even farm workers, just contractors, and of course no birds, butterflies, bees or flying insects. Between 30 August and 6 September we followed our Bee Line, walking some 80km from Edinburgh to our home along small roads, footpaths, cycle tracks, disused railway lines, through open moorland. We saw few butterflies, moths or bees and even noted a lack of midges.

Continue reading...

Scientists have reconstructed the "voicebox" of an extinct bird that lived at the time of the dinosaurs - and they say it honked or quacked like a duck.

The Spanish photographer Xavi Bou digitally combines sequential pictures of birds to create a single image, or chronophotograph, that reveals the shapes of their flight paths against Catalonian skies. His work shows the variety and beauty to be found in the daily activities of the local birds, including spiralling storks, swooping starlings and giddy swifts

Continue reading...

Max McMurdo has made a career out of turning household tat into chic new forms. But can his creations match his talk? We put him to the test

Max McMurdo stands on the doorstep surrounded by toolboxes, neat as a pin. A professional upcycler, he has offered to convert my worst bits of household junk into brilliant new forms. It’s hardly surprising that he is smiling: upcycling is a form of recreational optimism. The whole pursuit is underpinned by the belief that no tat is too tatty. All junk can be saved.

McMurdo, 38, defines upcycling as “adding emotional or financial value [to waste objects] through the addition of design”. The idea has been around since at least the 1990s, and while the principle of adding value to waste makes sense, I have always disliked most of the interiors styles it has generated. Too often, upcycling bolts an adjective – such as “shabby” or “industrial” – to the word “chic” in the hope of rendering rubbish desirable. But maybe Max will change my mind.

Continue reading...

A virus stole the gene coding for the poison of black widow spiders, scientists have found.

Biologist Ryan Killackey filmed for seven years in order to create an account of a remote forest community under pressure from US and Chinese oil companies. The result was Yasuni Man, which focuses on the Yasuni biosphere reserve in Ecuador. The ITT Initiative, which would have protected the Ishpingo, Tambococha and Tiputini regions, was killed off by President Rafael Correa in 2013. This month, the first oil from the Yasuni fields is due to be pumped up by a Chinese company and piped to customers in California

• Yasuni man is an intimate portrait of a beautiful land under siege for its oil

Continue reading...

Car manufacturers told they must address climate change by switching to low-emission models − or face a sell-off of their shares, reports Climate News Network

Major investors have warned the automotive industry it needs to accelerate its readiness for a low-carbon world if it is to retain their support and prosper.

Vehicle makers must put climate change specialists on their boards, engage better with policy-makers, and invest more heavily in low-emission cars, says a network of 250 global investors with assets of more than $24tn (£20tn).

Continue reading...

Sixth attack in 21 months persuades the premier, Mike Baird, to lobby federal government to install shark nets on north coast beaches

All beaches in Ballina on the New South Wales north coast are closed after a man was bitten by a shark while surfing, the sixth attack in 21 months in the area.

The attack has caused a backdown from the premier, Mike Baird, who has resisted the idea of shark nets on north coast beaches has now announced he will lobby for them to be installed.

Continue reading...

IMAGE POWER: A striking photograph will always stir more emotions and create a bigger impact than a spreadsheet of statistics, says acclaimed National Geographic photographer Thomas Peschak.

Wenlock Edge, Shropshire Even though the woundwort has lost its place in the pharmacy, bees visit these late flowers for the nectar tucked inside them

Woundwort grows from a hedge as if to mark some hurt, not to heal so much as to witness it. Hedge woundwort, Stachys sylvatica, belongs to the betony, horehounds and catmint of the waysides. It has small tight whorls of “blood and bandages” flowers – purply red clasps with white markings – nettle-like leaves and a hairy stem that when rubbed has a stink bad enough to do you good.

Related: Country diary: Baltimore, Ireland: For centuries these leaves were nature's gift to wearied travellers

Continue reading...

IEA report says energy efficiency a huge investment opportunity, and growing rapidly, but must be ramped up to avoid dangerous climate change.

September proved a bumpy month for the Victorian energy efficiency market, but ultimately it marked the first significant monthly recovery this year.

$1 million per megawatt hour? That's the cost imposed on the market when a gas generator slightly increased its output for 15 minutes during a recent high price event in South Australia. It's hard to imagine a better case for battery storage.

Queensland energy minister says federal Coalition has been solar scare mongering and will be out of a job if it continues to keep its head in the sand on renewables. But mainstream media has a long way to come as well.

Queensland panel says 50% renewables by 2030 not just doable, it will be "cost neutral" to consumers and won't affect reliability. It maps out three scenarios that will add more than 6,000 jobs, more than $5bn to state economy and cost a fraction of Coalition forecasts.

Most Australian households looking at battery storage just want to make the most of their solar investment and use as little grid supplied energy as possible. But what should they look to buy?

With space heating beginning to look like a high carbon option, can ‘person’ heating make a comeback? Developments in radiant heating technology suggest it can.

Solar shading are dirty words to the solar industry. Is it possible to beat shading and boost the output of a solar system?

AGL chief says 1.4MW solar PV array across Yalumba wineries in SA shows how distributed energy empowers business, offering greater control of energy use and costs, resilience during system failures.