Biggest American freshwater fish in danger

This video says about itself:

[White] Sturgeon at the mouth of the Harrison river, a tributary to the Fraser river in Canada.

From Scientific American:

Dammed if we do, dammed if we don’t: New World’s biggest freshwater fish at risk

By John Platt

Two of the world’s biggest freshwater fish are in big trouble, come reports from scientists in North and South America.

First up, the genetically distinct Kootenai River population of white sturgeon (Acipenser transmontanus), North America’s largest freshwater fish. This massive monster has been known to reach almost six meters in length and weigh half a metric ton, but its size hasn’t offered it any protection. In fact, it has made it more attractive, and the species has historically been heavily overfished.

The problem in the Kootenai River isn’t overfishing, although it is man-made: Montana’s Libby Dam, built in 1974. The dam prevents the river from the very flooding that used to tell the sturgeon it was time to spawn. Before the dam was built, an estimated 10,000 white sturgeon lived in the river. Now, just 500 remain, and they have not spawned in the wild in 35 years. Oops. …


Meanwhile, in South America, another of the world’s largest freshwater fishes—in fact, the largest species with scales—is also in danger of extinction, if it even still exists. A paper in the December issue of the Journal of Applied Ichthyology reports that the giant Amazonian arapaima (Arapaima gigas) are threatened by weak and unenforced fishing regulations in Brazil, despite the species’s protected status under the Convention on International Trade of Endangered Species of Wild Fauna and Flora (CITES).

Arapaima can reach more than four meters and weigh more than 180 kilograms. The fish actually comes to the surface to breathe, leaving it vulnerable to fishing with spears and nets.

Part of the problem with preserving the arapaima is that it has never really been studied, until now. Authors Leandro Castello and Donald Stewart examined several arapaima samples in museums and found that only one of them was actually the Arapaima gigas. “Our new analyses indicate that there are at least four species of arapaima,” Castello told BBC News. “So, until further field surveys of appropriate areas are completed, we will not know if Arapaima gigas is extinct or still swimming about.”

The Threadfin acara, Acarichthys heckelii, is widespread in the Amazon basin: here.

Did lemurs reach Madagascar on rafts?

This video is called Sifaka lemurs leaping and locomoting in Madagascar.


Natural rafts carried Madagascar’s unique wildlife to its shores

Jeremy Hance

January 20, 2010

Imagine, forty million years ago a great tropical storm rises up on the eastern coast of Africa. Hundreds of trees are blown over and swept out to sea, but one harbors something special: inside a dry hollow rests a small lemur-like primate. Currents carry this tree and its passenger hundreds of miles until one gray morning it slides onto a faraway, unknown beach. The small mammal crawls out of its hollow and waddles, hungry and thirsty, onto the beach. Within hours, amid nearby tropical forests, it has found the sustenance it needs to survive: in a place that would one day be named Madagascar.

The world’s fourth largest island, Madagascar is home to some of world’s most unique and bizarre wildlife, including 70 species of the much-loved lemur. But how did such animals reach the island, 300 miles from the African mainland? A new study published in Nature has uncovered the dramatic answer.

The researchers, Professors Matthew Huber of Purdue and Jason Ali of the University Hong Kong, write that species rode out to Madagascar on natural rafts, such as trees, which were blown out to sea. After surviving a harrowing, yet (according to the researchers) feasible trip, the immigrants would have reached the shores of their new home and propagated.

Using a computer simulation of ocean currents during that time, the researchers argue that the long migration would have been possible. The animals that reached the island would then have evolved in complete isolation over millions of years into the odd forms that survive today, such as the long-fingered aye-aye and the world’s tiniest chameleon.

Today, currents between Africa and Madagascar flow south and southwest—not east—making such rafting trips impossible. However according to the complex computer simulation, currents flowed eastward between 20 to 60 million years ago, the pivotal period when researchers say terrestrial species arrived in Madagascar. In addition, these currents were fast enough to bring animals across the 300 miles before they would have perished from thirst. As well, Madagascar’s fauna are all small-bodied and capable of long periods of dormancy, raising the chances of the success of their journey. The scientists argue that some of the animals may have been swept out into sea during hibernation, which would increase their chances of survival, since hibernating animals require little food or water.

The other theory of how Madagascar was populated entials a landbridge connecting Africa to Madagascar. However there is no physical evidence of such a landbridge and the land bridge hypothesis should mean that Madagascar would also contain large-bodied vertebrates, such as ancestors of giraffes, hippos, elephants, lions etc. But, of course, there is no record of any such animals reaching the island.

This is not true for (dwarf) hippos.

“I was very excited to see this paper,” says Anne Yoder director of the Duke University Lemur Center and a reviewer of the study. “Dispersal [byway of rafts] has been a hypothesis about a mechanism without any actual data. This takes it out of the realm of storytelling and makes it science.”

Madagascar is second only to Australia in terms of its number of endemic, i.e. unique, species, but is thirteen times smaller than Australia.

See also here. And here.

New theory on the origin of primates: here.

New Theory of Primate Origins Sparks Controversy: here.

Mankind’s closest living relatives – the world’s apes, monkeys, lemurs and other primates – are on the brink of extinction and in need of urgent conservation measures according to Primates in Peril: The World’s 25 Most Endangered Primates, 2008–2010: here. Photos here.

Meet Ares, a brand new baby Coquerel’s sifaka at the Wildlife Conservation Society’s Bronx Zoo. Like all lemurs, Coquerel’s sifaka is native only to the island of Madagascar where they are endangered due to habitat destruction. With the birth of Ares, the total population of Coquerel’s sifakas in accredited zoos rises to 51: here.

Guardian: Madagascar: trees reveal lemur secrets: here.

Video: Lemur conservation in Madagascar – Primate populations in the forests of Madagascar are declining: here.

Since it was far removed from the mainstream of African evolution, the Indian Ocean island of Madagascar witnessed some strange megafauna mammals during the Pleistocene epoch. A good example was the prehistoric primate Archaeoindris, a gorilla-sized lemur (named after the modern indri of Madagascar) that behaved like an overgrown sloth, and in fact is often referred to as the “sloth lemur”: here.

New Madagascar chameleon species: here.

Birds and mammals in new English nature reserve

This video from Britain is called Saltholme Wildlife Reserve.

From Wildlife Extra:

Unusual birdlife in residence after just 1 year at Saltholme

20/01/2010 00:02:19

RSPB Saltholme celebrates first birthday

January 2010. In the twelve months since its doors first opened, Saltholme has had almost 100,000 visits. RSPB Salthome wetlands offer a wild retreat within the industrial heartland of Tees Valley, and has attracted a great mix of wildlife enthusiasts and nature reserve first-timers.

Wildlife visitors – Bitterns, Sand martins, lapwings and even a corncrake

Sand martins turned up and used the nesting bank specially created for them. Common terns flocked to the purpose-built cockleshell-covered island in front of the visitor centre, and lapwings, peregrines and yellow wagtails have also been regular visitors. Some rare and secretive birds joined other wildlife on the reserve too, from a corncrake in mid-summer to two bitterns that have taken up residence this winter.

And the recent arctic conditions have brought all sorts of usually elusive birds up close to delighted visitors.

Reed buntings and water rails left the sanctuary of their usual reedbed homes to search for food, and there were amazing views of skylarks on ice of the main Saltholme pool.

Hares & voles

Other highlights were the ‘mad’ hares boxing, while water voles paddled around the reserves waterways.

Dave Braithwaite, Saltholme Site Manager, says: “Saltholme has brought nature to the doorstep of many of people that may not have even considered visiting a nature reserve before.

Saltholme has three architect-designed hides, including a striking watchpoint which overlooks one of its busiest pools. The state of the art visitor centre offers panoramic views of the wetland.

A group of sex-mad water voles rescued from one of Europe’s biggest sewage works prior to building work at the site are “breeding like rabbits” in their temporary home, Thames Water has said: here.

A petition, back by almost 22000 pledges from the Scottish public, will be handed to the Scottish Parliament today, demanding tougher action to tackle the illegal killing of birds of prey: here.

UK’s oldest known arctic tern returns to roost: here.

English dinosaur tracks protected

This video from Utah in the USA says about itself:

Travel Adventure: Kane County Dinosaur Tracks

180 million years ago you could see the dinosaurs who left behind the tracks we are seeing today.

From the BBC:

Dinosaur tracks to be protected

The tracks are at risk from exposure to the elements and damage from erosion

Dinosaur footprints discovered in Oxfordshire mudflats are to be protected as part of a geological conservation site.

Up to 40 sets of tracks, at Ardley Trackways near Bicester, include those belonging to large dinosaurs related to Brachiosaurus and Tyrannosaurus.

The tracks, found in 1997, are located alongside where the M40 now runs.

Natural England confirmed that the area has been made a site of special scientific interest (SSSI).

The board will decide whether to confirm the designation in four months, after a public consultation.

Researchers have been able to work out how fast the dinosaurs were travelling by studying the distance between individual footprints.

It is thought that some of the species reached speeds of up to 20mph (32kph).

Natural England is working with the owners and operators of the site to ensure that the fossilised tracks are preserved.

See also here.

China: Dinosaur “Death Pits” Created by Giant’s Footprints? Here. Tiny dinos perished in footprint death pits: here.

Dutch anti-immigration bureaucracy kills Haitian girl

This video says about itself:

Amnesty International is urging authorities in the Dominican Republic to immediately halt the mass deportation of Haitian migrants amid claims by the authorities that the move is necessary to prevent the spread of cholera.

For people who might think that I blame all the tragedies of the Haitian people on the United States government, armed forces, and corporations: no, others cause horrible problems as well.

Like Dutch authorities.

From Dutch daily Algemeen Dagblad:

Teenager dies because of immigration authorities’ procrastination

Denaise Jean-Baptiste might have lived safely in the Netherlands

PORT-AU-PRINCE – The 15-year-old Denaise Jean-Baptiste from Haiti would probably still be alive if the IND [Dutch immigration authorities] would not have procrastinated.

They procrastinated about the file about reunification with her mother in the Netherlands. Now, the girl has died during the violent earthquake in Haiti. The family’s lawyer has asked the Foreign Affairs department to grant permission to her brother and two sisters to come to the Netherlands soon.