Category Archives: blog

The rail that came back from the dead —

White-throated rail (Dryolimnas cuvieri cuvieri) (CC BY-SA 4.0) (Author - Charles J Sharp)

White-throated rail (Dryolimnas cuvieri cuvieri) (CC BY-SA 4.0) (Author – Charles J Sharp)

New research has shown that the last surviving flightless species of bird, a type of rail, in the Indian Ocean had previously gone extinct but rose from the dead thanks to a rare process called ‘iterative evolution’.

The research, from the University of Portsmouth and Natural History Museum, found that on two occasions, separated by tens of thousands of years, a rail species was able to successfully colonise an isolated atoll called Aldabra and subsequently became flightless on both occasions. The last surviving colony of flightless rails is still found on the island today.

This is the first time that iterative evolution (the repeated evolution of similar or parallel structures from the same ancestor but at different times) has been seen in rails and one of the most significant in bird records.

The white-throated rail ((Dryolimnas cuvieri)), also known as Cuvier’s rail, is a chicken-sized bird, indigenous to Madagascar in the south-western Indian Ocean. They are persistent colonisers of isolated islands, who would have frequent population explosions and migrate in great numbers from Madagascar. Many of those that went north or south drowned in the expanse of ocean and those that went west landed in Africa, where predators ate them. Of those that went east, some landed on the many ocean islands such as Mauritius, Reunion and Aldabra, the last-named is a ring-shaped coral atoll that formed around 400,000 years ago.

With the absence of predators on the atoll, and just like the Dodo of Mauritius, the rails evolved so that they lost the ability to fly. However, Aldabra disappeared when it was completely covered by the sea during a major inundation event around 136,000 years ago, wiping out all fauna and flora including the flightless rail.

The researchers studied fossil evidence from 100,000 years ago when the sea-levels fell during the subsequent ice age and the atoll was recolonised by flightless rails. The researchers compared the bones of a fossilised rail from before the inundation event with bones from a rail after the inundation event. They found that the wing bone showed an advanced state of flightlessness and the ankle bones showed distinct properties that it was evolving toward flightlessness.

This means that one species from Madagascar gave rise to two different species of flightless rail on Aldabra in the space of a few thousand years.

Lead researcher Dr. Julian Hume, avian paleontologist and Research Associate at the Natural History Museum, said: “These unique fossils provide irrefutable evidence that a member of the rail family colonised the atoll, most likely from Madagascar, and became flightless independently on each occasion. Fossil evidence presented here is unique for rails, and epitomises the ability of these birds to successfully colonise isolated islands and evolve flightlessness on multiple occasions.”

Co-author Professor David Martill, from the School of Earth and Environmental Sciences at the University of Portsmouth, said: “We know of no other example in rails, or of birds in general, that demonstrates this phenomenon so evidently. Only on Aldabra, which has the oldest palaeontological record of any oceanic island within the Indian Ocean region, is fossil evidence available that demonstrates the effects of changing sea levels on extinction and recolonisation events.

“Conditions were such on Aldabra, the most important being the absence of terrestrial predators and competing mammals, that a rail was able to evolve flightlessness independently on each occasion.” (Phys.org)

The high price endangered animals pay for charisma —

“Wanted: beautiful, intelligent companion well-versed in the art of conversation.” It’s a familiar story, but don’t expect a fairy-tale ending. In this instance, we’re talking about a transaction that condemns one of the protagonists to life imprisonment in a cage – or an untimely death in transit at the hands of traffickers. Not exactly a match made in heaven.

The visually stunning and vocally versatile yellow-naped amazon is a prime example of the heavy price that parrots pay for their good looks, brain power and loquaciousness. This species is one of the most highly coveted in the Central American pet trade and its population has been devastated by poaching and trafficking.

The island of Ometepe – a wildlife haven in the middle of Nicaragua’s largest freshwater lake – harbours an estimated 1,800-2,000 yellow-naped amazons. This represents the largest remaining population not just in Nicaragua but throughout the entire range of this endangered parrot. Poaching pressure is no less severe in this part of the world, but the Ometepe population has remained relatively unscathed by virtue of its inaccessibility. Even here, an estimated 40 percent of nests are thought to have been plundered in recent years to supply the illegal pet trade.

Yellow-naped Amazon parrot (CC BY 3.0) (Attribution-Matt edmonds at English Wikipedia)

Yellow-naped Amazon parrot (CC BY 3.0) (Attribution-Matt edmonds at English Wikipedia)

Local demand is at least partially responsible for the decline of the yellow-naped amazon – a staggering 25 percent of households in Ometepe keep parrots as pets – but national and regional demand are just as problematic, and there are disturbing reports of an increase in transcontinental trade, which could spell disaster for this beleaguered bird. Trafficking methods are also becoming more sophisticated – for example, portable incubators are increasingly being used to smuggle the parrots abroad before they have hatched. Clutches of eggs are harder to detect and easier to transport, as they don’t make noise or require feeding in transit.

Who’s A Naughty Boy, Then?

It is illegal to take yellow-naped amazons – eggs, nestlings or adult birds – from the wild, but the chances of being apprehended are slim. In the absence of any meaningful law enforcement, parrot poachers can transgress with virtual impunity. Anyone caught in possession of a parrot can expect to escape with, at worst, a metaphorical slap on the wrist.

There is no denying the global importance of this island stronghold and its treasure trove of yellow-naped amazons – which begs the question: why are there relatively few protection measures in place to safeguard the birds? Part of the answer lies in the sheer magnitude of the task. The cost of protecting even a small proportion of nest sites is prohibitive, and more resources are urgently needed.

The parrot’s predilection for holes in mature trees and its tendency to return to the same nest site year after year mean that breeding sites are easy for would-be poachers to pinpoint and stake out. With the best will in the world, it is all but impossible to guarantee island-wide protection.

Communities have a crucial role to play in addressing illegal wildlife trade, and Ometepe is no exception. Fauna & Flora International (FFI) has been working with islanders for many years to encourage the adoption of environmentally friendly and climate-smart farming practices. Those same people hold the key to the survival of the yellow-naped amazon.

Community-Led Solutions

FFI’s outreach activities are building local support for the protection of the parrots, and community-led patrols are already helping to combat poaching at known active nest sites. But there is potential to achieve much more by harnessing local knowledge. By establishing a network of guardians and providing incentive payments for nest protection, we hope to stay one step ahead of the poachers.

In this respect, we are aiming to learn from FFI’s successful sea turtle conservation efforts in Nicaragua, which have seen local community members make the transition from egg poachers to turtle guardians. But however effective the anti-poaching measures may be, we know that long-term protection of these parrots – as with sea turtles – will ultimately hinge on demand reduction.

With that in mind, FFI has launched an awareness campaign aimed at schools and other influential groups. We are working to understand the drivers behind parrot ownership and poaching, as a first step to changing local mindsets and attitudes. But this is a deeply entrenched cultural norm in Nicaragua, and will require sensitive handling. Before we claim the moral high ground, we need to remind ourselves that it wasn’t considered socially unacceptable in western circles to keep a pet parrot in a cage until relatively recently. As for stemming the international demand, that’s a whole different story. We’re currently on the lookout for the perfect partner to help FFI realise that ambitious goal. “Successful, active centenarian, passionate about parrots, seeks sympathetic funder for long-term relationship.” (Phys.org)

How jackdaws remember what they did where and when —

Western Jackdaw (CC BY 2.0) (Author - Maxwell Hamilton)

Western Jackdaw (CC BY 2.0) (Author – Maxwell Hamilton)

Corvids are capable of cognitive feats that almost resemble those of humans. Neuroscientists at Ruhr-Universität Bochum (RUB) intend to find out how their brain manages to fulfill such complex tasks – although its structure is completely different than that of the human brain. For a year, the researchers have been training two jackdaws in a complex behavioural experiment, where the birds learn to remember what they did where and when. The underlying processes in the brain are to be determined through subsequent neurophysiological analyses. An article on the research conducted by the work group Avian Cognitive Neuroscience, headed by Dr. Jonas Rose, has been published in the RUB’s science magazine Rubin.

Remembering places

For the purpose of the experiment, the animals learn to remember a sequence of locations that they visited and the colours they saw there. They have then to retrieve that information in a different location; if they do everything right, they are rewarded with food. The researchers use this task to study the basis of the so-called episodic memory. It stores unique events and is based on the fact that individuals are able to remember what they did where and when. Other groups have demonstrated in other behavioural experiments that corvids have this ability. However, the neural basis of that ability has as yet not been analysed.

At RUB, the jackdaws complete the experiment in a hexagonal aviary, where they have been undergoing daily training of approximately two and a half hours for the past year. The aviary is fitted out with touchscreens on four walls. On three of them, dots in different colours appear that the animals have to pick. Only after the first dot has been picked does the next one appear, etc. In a fourth location, the bird then has to retrieve the information which colour it saw in which location.

Learned in a month

In order to retrieve the sequence of the locations, the animal had first learned to allocate symbols to the locations: a camping site, bathroom, and a port. However, the symbols are never presented in the locations themselves. The jackdaws only see them on the fourth touchscreen, where they have to provide their answer. Initially, they used to pick the symbols at random; only if they hit the correct sequence, they were rewarded with food. Thus, they learned to allocate camping site, bathroom and port to one of the other three touchscreens.

“We weren’t sure if the animals would be able to learn this,” explains Jonas Rose. “But then, they did it quite fast, within the space of one month.” In 60 to 80 per cent of all experiment rounds, the animals list all three locations correctly. In this experiment design, the probability of getting the answer right by guessing is approximately 17 per cent.

Working memory overloaded?

Now, the birds are training to remember which colour they saw at which location, with the sequence of locations and the allocation of colours changing in each round. At first, the jackdaws struggled quite a bit. “We are trying to determine if the animals’ working memory simply can’t cope with so much information,” explains Rose, “or if they struggle with the colour task as such.”

To this end, the researchers don’t require the jackdaws to allocate colours to locations in every trial; rather, in some trials the birds only have to list either the sequence of locations or the sequence of colours. Today, the animals answer correctly in 20 per cent of all experiment rounds where they have to name both locations and colours; thus, they score higher than the probability of guessing, which amounts to 5.5 per cent. The biopsychologists from Bochum are therefore still confident that the animals can learn the task. If not, they will gradually simplify the experiment. (Phys.org)

One of world’s oldest bird species found at same Canterbury site as monster penguin —

Protodontopteryx ruthae (Illustration by Derek Onley)

Protodontopteryx ruthae (Illustration by Derek Onley)

One of the world’s oldest bird species has been discovered at the same North Canterbury site a monster penguin fossil was found.

Bony-toothed birds (Pelagornithids), an ancient family of huge seafaring birds, were thought to have evolved in the Northern Hemisphere, until the discovery of the family’s oldest but smallest member in New Zealand.

At 62 million years old, the newly-discovered Protodontopteryx ruthae is one of the oldest named bird species in the world, inhabiting New Zealand soon after the end of the dinosaurs.

While its descendants were some of the biggest flying birds ever, with wingspans in excess of 5 metres, Protodontopteryx was only the size of an average gull. Like other members of its family, the seabird had bony, tooth-like projections on the edge of its beak.

The seabird fossil was identified by the same team that recently announced the discovery of a 1.6 metre-high giant penguin from the same site.

Amateur palaeontologist Leigh Love discovered both the penguin and the partial Protodontopteryx skeleton just months apart at the Waipara Greensand fossil site. 

The bird was named Protodontopteryx ruthae after Love’s wife Ruth.

Scofield said the age of the fossilised bones suggested pelagornithids evolved in the Southern Hemisphere back when New Zealand had a tropical climate and a sea temperature of about 25 degrees Celsius.

“While this bird was relatively small, the impact of its discovery is hugely significant in our understanding of this family. Until we found this skeleton, all the really old pelagornithids had been found in the Northern Hemisphere, so everyone thought they’d evolved up there.”

Mayr said the discovery of Protodontopteryx was “truly amazing and unexpected”.

“Not only is the fossil one of the most complete specimens of a pseudotoothed bird, but it also shows a number of unexpected skeletal features that contribute to a better understanding of the evolution of these enigmatic birds.”

Later pelagornithid species evolved to soar over oceans with some species measuring up to 6.4 metres across. 

Protodontopteryx’s skeleton suggests it was less suited for long-distance soaring than later pelagornithids and probably covered much shorter ranges. Its short, broad pseudoteeth were likely designed for catching fish. Later species had needle-like pseudoteeth which were likely used to catch soft-bodied prey like squid.

The last pelagornithid species died out 2.5 million years ago, just before modern humans evolved.

The Waipara Greensand site has yielded several important scientific discoveries for Love in recent years. In 2014 he made headlines when a fossil he found was recognised as belonging to an unknown group of flying seabirds and was named Australornis lovei.

The following year Love discovered the world’s oldest tropicbird fossil, which also revealed the true origins of a bird which until his discovery had only ever been found in the northern hemisphere.

Some of the discoveries, including the Protodontopteryx fossil, will be displayed in an exhibition about ancient New Zealand at the Canterbury Museum later this year. (Stuff)

Endangered sparrows are threatened by climate change —

Dusky Seaside Sparrow, one of the numerous subspecies of Seaside sparrow, has recently become extinct (US Fish & Wildlife Service)

Dusky Seaside Sparrow, one of the numerous subspecies of Seaside sparrow, has recently become extinct (US Fish & Wildlife Service)

A new study in The Condor: Ornithological Applications finds that some sparrow species will go extinct within the century due to climate change.

Seaside sparrows (Ammospiza maritima) and saltmarsh sparrow (A. caudacuta) sparrows are closely related species and among only five bird species that are almost completely restricted to coastal salt marshes for their entire life. These sparrows’ nests are predominantly destroyed by predators or flooding.

Salt marshes are globally limited to about 30,000 square miles (45,000 square km), with one-third of the total on North American coasts. Of the 25 species or subspecies limited to tidal wetlands worldwide, 15 are restricted to the US Atlantic and Gulf coasts. Given rapid climate changes and other threats to salt marsh ecosystems, many of these species are in serious danger.

The global breeding range of the saltmarsh sparrow extends from Virginia to Maine, with a population estimate of 60,000 birds. Sea-level rise can negatively impact breeding seaside and saltmarsh sparrows by reducing the amount of available habitat, and by increasing nest flooding rates. Furthermore, the high human population densities of Mid-Atlantic states also make it difficult for sparrows to thrive in the region.

This study aimed to estimate population trajectories for seaside and saltmarsh sparrows within Edwin B. Forsythe National Wildlife Refuge in New Jersey, identify the primary drivers of those trajectories, and explore potential management strategies to prevent declines.

The researchers found that seaside sparrows persisted under a 1 ft (0.35 m) rise in sea level scenario and also under a sea level rise of almost 2.5 ft (0.75 m). Saltmarsh sparrows survived in neither scenario. With a 1 ft rise in sea level, the seaside sparrow population experienced a compound decline of .35% a year. Under the 2.5 ft sea level rise scenario, this decline increased to .56% a year. The saltmarsh sparrow median time to quasi-extinction was 20 years under both scenarios.

The results indicated that seaside sparrows are likely to persist, while saltmarsh sparrows are likely to become locally extinct in the next 30 years.

“Given the projected increases in sea level over the next few decades and threats from predators, we will need to implement timely and creative actions to avoid extinction of saltmarsh sparrows,” said the paper’s lead author, Samuel Griffith Roberts. (Phys.org)

The Most Promiscuous Bird in the World —

Saltmarsh sharp-tailed sparrow (Licenced under GFDL 1.2) ( Author - Wolfgang Wander)

Saltmarsh sharp-tailed sparrow (Licenced under GFDL 1.2) ( Author – Wolfgang Wander)

UConn ornithologist Chris Elphick and his colleagues carried out DNA tests to discover the paternity of Saltmarsh Sparrow (Ammospiza caudacutus) nestlings.

Saltmarsh Sparrows practically blend into the grays and browns of the marshes they inhabit along a narrow fringe of coast in Connecticut and other eastern states.

But as new research by CLAS faculty member Chris Elphick and colleagues shows, these shoreline birds are remarkable for their “extreme levels of multiple mating” and are thought to be the most promiscuous birds in the world.

Elphick’s work was carried out in collaboration with Christopher E. Hill from Coastal Carolina University and Carina Gjerdrum of the Canadian Wildlife Service.

In an article in The Auk, a premier ornithological journal, the scientists describe mating patterns that give new meaning to the term “multiple paternity.”

Fifty-seven out of 60 broods had at least two chicks with different fathers. At least 97 percent of females were mating with more than one male. In any one nest, it was impossible to tell who the fathers were of all the chicks without checking DNA.

While most small birds have monogamous relationships, ornithologists say that low levels of “extra-pair mating” happen in many species. Even so, the promiscuity levels seen in Saltmarsh Sparrows are extraordinarily high. Only the Greater Vasa Parrot of Madagascar and the Superb Fairy-Wren of Australia are known to come close.

The researchers didn’t set out to track the sexual habits of the sparrows. But as an offshoot of their long-term research on the birds, funded by Connecticut Sea Grant, the US Environmental Protection Agency, and the Connecticut Department of Environmental Protection, they decided to track whether reports of unusual mating patterns were true.

Elphick, an assistant professor of ecology and evolutionary biology, and Gjerdrum, then an EEB research technician who now works for the Canadian Wildlife Service, collected data on sparrow paternity for two summers in nine marshes along the Connecticut coast.

To do their sparrow research, they catch the birds in fine mesh nets and band them. For this study, they took blood samples to test the birds’ DNA. Chicks in the nest were also sampled.

Chris Hill, a biologist at Coastal Carolina University, did the molecular analyses for the study.

It was easy to determine maternity of the chicks, because the mothers sit on the nests, Elphick says: “The tricky part is the fathers.”

Male Saltmarsh Sparrows take no part in chick rearing, so the only way to associate a male with a brood is to catch all the males in an area and conduct paternity tests.

Easier to figure out was whether the chicks in a nest had the same father, and the DNA analyses showed how rare that was.

The Saltmarsh Sparrows face multiple habitat threats, and their conservation is the focus of Elphick’s research. They live only in a narrow fringe of coastal land from Virginia to Maine, a habitat favored by humans for development and seaside homes.

Their saltmarsh nests are flooded regularly, so many chicks drown. As sea levels rise with global warming, the birds’ very existence is threatened.

But for now, they hold the world’s record for promiscuity in the bird world. (Phys.org)

Rare and world’s fattest parrot, Kakapow, has record breeding season —

Kakapo (CC BY 2.0) (Author - Department of Conservation) (Photo Chris Birmingham)

Kakapo (CC BY 2.0) (Author – Department of Conservation) (Photo Chris Birmingham)

The world’s fattest parrot, the critically endangered kakapo, has enjoyed a record breaking breeding season, New Zealand scientists said , with climate change possibly aiding the species’ unique mating spree.

Less than 50 years after the flightless nocturnal bird was thought to have been extinct, at least 75 chicks are expected to survive this year, Andrew Digby, a science advisor to New Zealand’s kakapo recovery, operation told AFP in April 2019.

Digby oversees a breeding programme so precisely monitored that scientists can state the last of 249 eggs laid will hatch on which day.

It will significantly boost the population which has grown to 147 adults since a small number of the plump green, yellow and black birds were discovered in 1970.

Digby described the kakapo as an “unusual” parrot as the females control the breeding process and only mate every two to four years when New Zealand’s native rimu trees are full of fruit.

“We don’t quite know what the trigger is but one of the things we are looking at is that the rimu berry is really high in vitamin D, a super food basically, which is associated with fertility and health,” he said.

The rimu trees have produced a bumper crop this year with Digby saying one theory was that climate change and temperature fluctuations could be behind the berry bonanza.

The surviving kakapo—whose name means “night parrot” in Maori—are kept on four predator-free islands off the New Zealand coast.

At the start of the breeding season, the males which weigh about 4.0 kilograms (nine pounds) put themselves on display while the females choose a partner.

They mate and then end the relationship, shutting the male out of the incubation and rearing processes.

The kakapo recovery programme is so tightly monitored that although they remain in the wild, each one has a radio transmitter attached to its body and there are monitoring systems embedded in their nests.

Digby knew that of the 50 adult females, 49 produced 249 eggs, of which 89 have so far hatched and 75 were expected to make it to adulthood.

That is more than double the success rate from the last breeding season three years ago.

“It’s probably one of the most intensively managed species in the world,” said Digby, who wants at least 500 birds before any thought is given to easing up the intensity of the recovery operation. (Phys.org)

The Cerrado once connected the Andes with the Atlantic Rainforest —

Buff-browed foliage-gleaner (CC BY-SA 2.0) (Author - Cláudio Dias Timm from Rio Grande do Sul)

Buff-browed foliage-gleaner (CC BY-SA 2.0) (Author – Cláudio Dias Timm from Rio Grande do Sul)

The tropical forests of the Andes and Brazil’s Atlantic Rainforest biome are separated by almost 1,000 km of drier areas with open vegetation in the Chaco, Cerrado (Brazilian savanna), and Caatinga (Brazilian semiarid) biomes. Today, these tropical forests are not connected, but the fact that they share closely related species and lineages suggests that these biomes were connected in the past. For example, 23 rainforest bird species have been found in both the Andean and Atlantic tropical forests.

Several published studies reinforce such hypothesis. What scientists do not know for sure is whether this connection consisted of past gallery forests along rivers in what is now the Chaco (which spans across southern Bolivia, northern Argentina and Paraguay) or the Cerrado (in part of Bolivia, central-west Brazil and northern Paraguay).

According to a new study based on genomic and biogeographical data for two bird species —  buff-browed foliage-gleaner (Syndactyla rufosupercilita) and planalto foliage-gleaner or russet-mantled foliage-gleaner (S. dimidiata) — the past connection between Andean and Atlantic tropical forests ran through the Cerrado. Such connection may have emerged several times during the Pleistocene, the geological epoch that lasted from approximately 2.5 million years ago to 11,700 years ago.

The study was part of a research project conducted by Gustavo Cabanne, an ornithologist at Argentina’s Museum of Natural Sciences (MACN), in collaboration with Cristina Yumi Miyaki, a professor at the University of São Paulo’s Bioscience Institute (IB-USP) in Brazil. Results of the study were published in the journal Molecular Phylogenetics and Evolution.

Biogeography is the study of the relationships among living beings, latitude, elevation and climate over time. Paleobiogeography focuses on species distribution and relationships in remote epochs. An understanding of the paleobiogeography of the species that inhabit certain biomes in the present can help scientists infer the distribution of these same biomes in the past.

“The main challenge in biogeographical research is integrating and interpreting the information obtained from several sources, such as data on biological components and genomes for the species analyzed, geology and paleoclimate, palynology [pollen and spores], and even remote sensing data from satellite imagery,” Miyaki said.

“We needed to collect and analyze all these kinds of data in order to investigate the hypothesis that there was an ancient connection between the Andean and Atlantic tropical forests and to test whether this connection ran through the Cerrado or the Chaco. The connection may have consisted of gallery forests that, during the Pleistocene, would have been remnants of wetland vegetation crossing more arid biomes.”

According to Cabanne, the existence of a connection between the Andean and Atlantic tropical forests is supported by palynological studies, among others, according to which both forests expanded transitorily in some regions (such as the Cerrado) toward the Andes during the most recent glacial cycle and last glacial maximum, i.e., the coldest period among the various ice ages that occurred in the past 2.5 million years (at least 11 have been identified).

“In this past biogeographical context, the Andean and Atlantic tropical forests may have served as refugia. Their dynamic history [connection and isolation cycles] may have been an important driver of speciation in the Neotropics [a region comprising Central and South America, the Caribbean and parts of Mexico and the United States],” Cabanne said.

In the present interglacial period, Cabanne explained that these biomes represent forest refugia, where isolated organisms in either biome are expected to differentiate. During the Pleistocene ice ages, both forests were connected, allowing for gene flow between forest domains.

Genetic and computational analysis

In the study published in Molecular Phylogenetic & Evolution, researchers chose to study the Buff-browed Foliage-gleaner, a New World ovenbird whose scientific name is Syndactyla rufosuperciliata, a passerine belonging to the order Passeriformes and family Furnariidae, as do other ovenbirds, such as the Rufous hornero (Furnarius rufus) and 230 other species found in Argentina, Bolivia, Brazil, Ecuador, Paraguay, Peru and Uruguay. There are five recognized subspecies in this taxon.

S. rufosuperciliata is an appropriate model with which to explore the Andean-Atlantic forest connection because it inhabits both the main forest domains and the areas that could have been directly involved in bridging them: the gallery forests of the eastern Chaco and some parts of the southern Cerrado,” Cabanne said.

Researchers used niche modeling to investigate the historical connectivity between the two regions. They then used DNA sequences from 71 birds and the genomic analysis of samples from other 33 specimens to evaluate the genetic structure of the population and the gene flow within the species. Lastly, they performed population model selection with the aid of approximate Bayesian computation (ABC), a method of inference based on summary statistics.

According to the researchers, their genomic analysis showed that the populations of S. rufosuperciliata now found in the Andean and Atlantic tropical forests belong to different lineages, but hundreds of thousands of years ago, the species was far more widely distributed, and its lineages were less differentiated from a genomic standpoint.

As the ice age continued and the vegetation in the Cerrado advanced and retreated, Andean and Atlantic birds became isolated from each other for tens of thousands of years, leading to diversification into two lineages.

The data also suggested new contacts between the eastern and western populations of the species during the interglacial periods of the Pleistocene, when temperatures rose and rainforests advanced, permitting cross-breeding between the two lineages and new gene exchanges.

The analysis of genomic diversity between Andean and Atlantic birds combined with paleoclimate data suggested that these gene exchanges occurred via the Cerrado to the north rather than via the Chaco further to the south.

“Our results showed that the Andean and Atlantic tropical forests were refugia and that populations of the species from both regions made contact via the Cerrado,” Cabanne said. “This suggests that the historical dynamics of the Andean and Atlantic forests played an important role in the evolution of forest birds in the region.”

“Our findings are consistent with studies of other organisms and may indicate a more general pattern of connectivity among biomes in the Neotropics,” Miyaki added.

In addition, this new study and previous research by the same group “point to high levels of cryptic diversity [meaning morphologically similar but genetically diverse species] between the Andes and Atlantic Rainforest biomes and suggest that the Andean population of S. rufosuperciliata should be recognized as an independent species,” Cabanne added. (Phys.org)

Rooster Maurice wins legal battle over noise with neighbours in France —

Corinne Fesseau with Maurice in her garden at Saint-Pierre-d'Oléron in La Rochelle (AFP)

Corinne Fesseau with Maurice in her garden at Saint-Pierre-d’Oléron in La Rochelle (AFP)

Maurice, who roosts on the picturesque isle of Oléron off the Atlantic coast, was accused of disturbing a retired couple who own a holiday home nearby.

News of his legal troubles flew around the world, gaining him a flock of supporters.

His owner, Corinne Fesseau, was cock-a-hoop at news of the ruling.

“It’s a victory for everyone in the same situation as me. I hope it will set a precedent for them,” she was quoted by AFP news agency as saying.

At a hearing in July, her lawyers had argued the complaint was ridiculous because crowing roosters were part of country life.

Ms Fesseau, who has lived on Oléron for 35 years, would have had to move or somehow silence Maurice if the judge had ruled against her.

She now will be given €1,000 (£900; $1,100) in damages from the plaintiffs instead, her lawyer said on 5 Sept. 2019.

The legal battle involving the bird saw a “Save Maurice” petition garner 140,000 online signatures.

The four-year-old has become a celebrity of sorts in France, where the Gallic Cockerel is one of the national emblems.

Merchandise has been made in his honour and letters of support have come from as far away as the United States, according to Reuters news agency.

The high-profile case is considered an illustration of the growing tension between residents living in rural France and those moving to escape city life.

“This is the height of intolerance – you have to accept local traditions,” Christophe Sueur, the mayor in Ms Fesseau’s village, told AFP.

The mayor of another town, Bruno Dionis du Sejour, wrote an open letter in May calling for the sounds of rural life – including cows mooing and church bells – to be inscribed on France’s heritage list to protect them against such complaints. (BBC News)

Do songbirds pay a price for winter wandering? —

Red-breasted nuthatch (CC BY-SA 3.0) (Author - Cephas)

Red-breasted nuthatch (CC BY-SA 3.0) (Author – Cephas)

In years when winter conditions are especially harsh, birds that depend on conifer seeds for food are sometimes forced to leave their homes in northern forests and wander far from their normal ranges to find enough to eat. A new study published in The Auk: Ornithological Advances uses citizen science data to show for the first time that these winter movements—called “irruptions”—lead to a decline in birds’ population density in their breeding range the following summer, suggesting that irrupting birds succumb to the difficulties of avoiding predators and finding food in unfamiliar landscapes.

Many birdwatchers love irruptions, because they can temporarily bring seldom-seen boreal birds south in large numbers. However, we know very little about how these journeys into unfamiliar territory actually affect bird populations. Red-breasted Nuthatches are a useful species in which to study this, because they return to the same core breeding areas even after winters with massive irruptions, making it possible to track how their breeding populations are doing from one year to the next.

Environment Canada’s Erica Dunn checked more than fifty years of records from Ontario’s Long Point Bird Observatory (LPBO) against citizen science data from Project FeederWatch, the Christmas Bird Count, and eBird to confirm that fall irruptions at Long Point are a good indicator of what’s going on with nuthatches across North America in any given year. Then, she used Breeding Bird Survey data to see how nuthatches fared in summers following major irruptions and found that breeding population density tended to dip noticeably after a winter where nuthatches had wandered more widely than usual.

This is the first study to demonstrate a correlation between the magnitude of birds’ winter irruption and their population density during the following breeding season. While these large-scale winter movements may be a necessity for birds in years where food is scarce, the rigors of travel, exposure to predators, and need to find food in unfamiliar places might take a toll. (Phys.org)