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4 mars 2016 5 04 /03 /mars /2016 17:21

Ceci est une suite à "Un rocher sur la lande" (paragraphe : "Le paradoxe yakoute") mis en ligne le 27 février dernier.

Le spécialiste sud - coréen du clonage Hwang Woo - suck, déjà investi dans un programme de reconstruction du mammouth laineux, a entamé des recherches pour la renaissance du lion des cavernes, à partir de la découverte, l'an dernier, de 2 lionceaux "vieux" de 12000 ans en république de Sakha (Yakoutie). Siberian Times, ce jour. South Koreans kick off efforts to clone extinct siberian cave lions.


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4 mars 2016 5 04 /03 /mars /2016 17:04

Verte, bleue, et même orange, en fonction de la lumière incidente...

La météorite géante qui a explosé au dessus de la Tunguska en 1908 a t - elle constellé le sol de pierres vertes plus précieuses que les émeraudes? Siberian Times, ce jour. Olga Gertcyk. Was this "emerald" brought to earth 108 years ago by the Tunguska meteor?


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4 mars 2016 5 04 /03 /mars /2016 11:11

Ceci fait suite à "Le Miroir : la baleine - rhytine en reconquête", mis en ligne le 10 novembre 2015.

L'ARBRE AU SABOT ET LE CHEVAL PÂLE. "Gallon of Milk", baleine grise albinos, vient d'être observée sur la côte Baja California, Mexique. Tenplay, ce jour.


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4 mars 2016 5 04 /03 /mars /2016 10:53


Ceci fait suite à l'article "Mort sur la route", mis en ligne le 25 octobre 2015


UNE NICHE ECOLOGIQUE NE RESTE JAMAIS VIDE. Le léopard "Typhoon" a investi le territoire de "Meamur", vacant depuis le décès de celui - ci. Vladivostok Times, ce jour.

Леопард Тайфун занял территорию погибшего в Приморье крестника Ильи Лагутенко

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3 mars 2016 4 03 /03 /mars /2016 16:40

Les cétacés se regroupent par espèce pour consommer les harengs le long des 150 miles du Georges Bank (Cape Cod). Science Daily, hier.


For a few weeks in early fall, Georges Bank -- a vast North Atlantic fishery off the coast of Cape Cod -- teems with billions of herring that take over the region to spawn. The seasonal arrival of the herring also attracts predators to the shallow banks, including many species of whales.

Now researchers from MIT, Northeastern University, the Institute of Marine Research in Norway, and the National Oceanic and Atmospheric Administration, have found that as multiple species of whales feast on herring, they tend to stick with their own kind, establishing species-specific feeding centers along the 150-mile length of Georges Bank. The team's results are published today in the journal Nature.

Based on acoustic data they collected in the region in 2006, the researchers identified and mapped the calls of various whales, and discovered a clear grouping of species within the dense herring shoals: Humpback whales congregated in two main clusters, at either end of the spawning grounds, while minke, fin, and blue whales set up feeding territories in the space in between.

In general, calls from each whale species increased dramatically at nighttime, when herring tended to form extremely dense shoals. During the day, these whale calls dissipated, as herring scattered throughout the seafloor.

These results represent the first time that scientists have observed such predator and prey interactions over a large marine region.

"It's known that different marine mammal species will eat fish, but no one has mapped their simultaneous feeding distributions over these huge scales," says Purnima Ratilal PhD '02, associate professor of electrical and computer engineering at Northeastern University. "Maybe there is some territorialism going on, or maybe they are preferentially selecting these locations based on their different foraging mechanisms. That's material for new research."

Ratilal and her husband, Nicholas Makris, professor of mechanical engineering at MIT, along with their students, are co-authors of the paper.

Fishing for sound

In 2006, Makris and Ratilal led a two-week cruise to Georges Bank, initially to track and study the behavior of populations of herring, which can number in the billions within a single shoal. The team had developed a remote-sensing system that uses acoustics to instantaneously image and continuously monitor fish populations over tens of thousands of square kilometers. Unlike conventional technologies, their system uses the ocean as a waveguide through which acoustic waves can travel over much greater distances, to sense the marine environment.

To get a much wider, more detailed view of the herring populations, Makris and Ratilal deployed 160 hydrophones during their 2006 cruise, towing the array, like a "big acoustic antenna," in and around Georges Bank. Using their ocean acoustic waveguide sensing technique, they mapped the evolving shoals over the two-week period in October.

During that cruise, the group remembers hearing distinct sounds coming through the ship's hull.

"We were hearing these strange haunting sounds in the galley, like an upsweep, then a down-sweep," Makris recalls. "Purnima recognized these were whale calls, and had all the characteristics of a classic humpback song. At that point she started the research that led to the current paper in Nature, which she spearheaded."

Makris notes that such whale calls have been heard through the hulls of ships for thousands of years.

"The Patogonian Indians even had a name for them: 'Yakta,'" Makris says. "People had been listening to these sounds for a very long time, and it's really this century that we're starting to localize and observe their behavior."

Hearing hotspots in the night

The group continued looking through the data, even after they had analyzed them for herring signals, to look this time for whale calls. The team developed a technique to sift through the acoustic data for interesting signals -- a method called passive ocean acoustic waveguide remote sensing (POAWRS).

Through the years, the team gathered research on the characteristics of certain whale species' calls and looked for these characteristics in their acoustic data. They eventually identified several hundred thousand calls, mostly along the northern edge of Georges Bank.

"Different marine mammals in the ocean produce different sounds, sort of related to their size," Ratilal says. "Humpbacks have a distinct song, while some species of tooth whales can sound like birds chirping."

"Fin whale calls, on the other hand, are in the register of a bass guitar," Makris adds.

The researchers located the source of each call by triangulation and other methods unique to waveguides, and found that the call rates of four main species of whales observed -- humpback, sei, minke, and blue -- tended to go up significantly at night, possibly in response to the increasing number of herring.

"Spawning herring typically don't form big shoals during daytime because it's too risky they can get caught more easily," Makris notes. "So they form just as the sun goes down. That's when the whale calls start going wild and begin to come from on top of the shoals."

These calls were concentrated in species-specific "hotspots," with humpback whale calls bookending the other three species, all along the northern length of Georges Bank.

The group found that humpbacks in particular emitted a distinct pattern of calls that may indicate a cooperative feeding ritual, which others have observed.

"The whales will circle the herring, and then one will blow a bubble to contain the fish group, and another will scream and scare the fish into a tight ball," Ratilal says. "Then another will give a signal, and they'll all come up with their jaws open."

Going forward, the team hopes to tease out more marine behaviors in their dataset.

"With this technology, you can really sense a lot of things," Makris says. "Fish and marine mammals are just two examples." Ratilal adds, "There are quite a few other interesting phenomena in our dataset."

Journal Reference:

Delin Wang, Heriberto Garcia, Wei Huang, Duong D. Tran, Ankita D. Jain, Dong Hoon Yi, Zheng Gong, J. Michael Jech, Olav Rune Godø, Nicholas C. Makris, Purnima Ratilal. Vast assembly of vocal marine mammals from diverse species on fish spawning ground. Nature, 2016

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3 mars 2016 4 03 /03 /mars /2016 16:16

Cet article fait suite à "La Merveille et la Gloire", paru sur ce blog le 3 novembre 2015.


Daily Mail, hier. Les scientifiques attendent avec impatience la naissance de plusieurs protées anguillards (Proteus anguinus), ou salamandres blanches, prévus en Slovénie dans les jours qui viennent. Cet animal aveugle, qui vit dans des grottes aquatiques plongées dans l’obscurité, ne pond qu’une ou deux fois par décennie. A Londres, le Daily Mail souligne que ce sont “les seuls vertébrés cavernicoles d’Europe” et qu’“ils peuvent vivre jusqu’à cent ans, mais ne se reproduisent que très rarement”.

Le quotidien raconte que les “premiers documents historiques sur les protées anguillards datent de la fin du XVIIe siècle. De fortes pluies avaient inondé les grottes et fait ressortir à la vue des humains ces pâles créatures. Les gens qui les avaient alors trouvées croyaient qu’il s’agissait de jeunes dragons vivant dans les entrailles de la terre.”

L’observation de la reproduction de ces animaux en milieu naturel est un événement particulièrement rare. Là, les salamandres vivent dans un aquarium spécialement aménagé dans la grotte de Postojna en Slovénie. “Les chercheurs utilisent des caméras infrarouges pour filmer la femelle et ses œufs – qui ont été soigneusement placés sous un rocher – sans les déranger”, détaille le Daily Mail.

Sur les 55 œufs pondus, seuls quelques-uns devraient éclore, et les biologistes font tout ce qu’ils peuvent pour les protéger des prédateurs et des changements trop brusques de température.

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2 mars 2016 3 02 /03 /mars /2016 17:02

L'année 2015 aura été celle d'un basculement qualitatif de la lutte contre le braconnage dans l'extrême orient russe. Les résultats obtenus en la matière sont les meilleurs jamais enregistrés, et la période présente est marquée par une intense réflexion sur l'évolution sensu lato des méthodes de ciblage. Voir pour le détail : Amur Tiger Centre, ce jour.


Voir aussi : WWF Russie, ce jour.

Подведены итоги работы охотнадзора Приморского края в 2015 году

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2 mars 2016 3 02 /03 /mars /2016 16:30

Quatre nouvelles réserves à tigres devraient voir le jour en Inde (leur création a été formellement approuvée par le gouvernement). Elles seront établies respectivement à Ratapani (Madhya Pradesh), Sunabeda (Odisha), Orang (Assam), Guru Ghasidas (Chhattisgarh). En outre,des propositions sont actuellement à l'étude concernant 7 réserves à tigres supplémentaires : Suhelwa (Uttar Pradesh), Mhadei (Goa), Dibang (Arunachal Pradesh), Cauweri MM Hills (Karnataka). Pour le seul Tamil Nadu, 3 futures réserves potentielles sont à l'étude : Srivilliputhur Grizzled Giant Squirrel, Megamalai Wildlife sanctuaries et Varushanadu Valley. L'ensemble est destiné à éviter les goulets d'étranglement territoriaux auxquels la population croissante de tigres allait être inévitablement confrontée à l'avenir si de nouveaux espaces ne leur avaient pas été spécialement dédiés. The Times of India, hier. In - principle approval given to 4 new tiger reserves : Government.


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1 mars 2016 2 01 /03 /mars /2016 16:18

Dans le Sud de la péninsule du Kamtchatka, le lac Kurilskoye est pris par les glaces, pour la première fois depuis 10 ans. Ceci ne facilite pas la vie des canards, cygnes, et pygargues de Steller. The Siberian Times, ce jour. Global warming? Kurilskoye Lake freezes for first time in 10 years.


Le Kurilskoye est un lac de cratère contenu dans une vaste caldeira. Sa superficie de 77 km2 en fait le troisième plus grand lac du Kamtchatka, et le second plus grand lac d'eau douce derrière le lac Kronotsky. Il a une profondeur moyenne de 176 m, et une profondeur maximale de 306 m. Les premiers européens qui l'ont découvert furent des cosaques, en 1703. Ce lac est aussi le site de reproduction le plus important d'Eurasie pour le saumon sockeye (et le deuxième du monde derrière l'Alaska), au sein d'une péninsule qui abrite à la fois la plus grande profusion et la plus grande diversité de saumons au monde (au moins six espèces différentes y prospèrent), et dont sont originaires 15 à 25% des saumons du Pacifique.

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28 février 2016 7 28 /02 /février /2016 09:29


Ceci fait suite à "Kamtchatka, en toute logique" publié sur ce blog le 30 septembre 2015.

Loren Coleman on September 16th, 2006

Writing in an “A manatee, off our coast?” in the Chinook Observer of Long Beach, Washington State, September 13, 2006, Captain Ron Malast writes:

There have some unusual sightings and catches along the Washington Coast this summer, but none more bizarre than the sighting of a manatee. While trolling for tuna on a course parallel to the Big Dipper, at about 40 miles off the coast, I received a radio call from a skipper of another charter boat. The skipper, for whom I have great respect as a fisherman and a straight shooter, wishes to remain anonymous for fear of being put in a straight-jacket and sent to a loony bin.

He said, “Did you see that? It was a manatee. It was bigger than a sea lion and about 12 feet long. At first I did not know what it was, but we cruised closer to it and I looked it straight in the eye. I then knew exactly what it was, it stayed on the surface for about two minutes, unafraid and then slipped off into the deep. When my brother, who was also on the charter boat, and I got home, we immediately got on the computer and pulled up a picture of a manatee and it was the same mammal that we had seen that afternoon. I will remember it to my dying day for what it was – a manatee.”

Zoologist Bernard Heuvelmans was one of the first to recognize the fact that Steller’s Sea Cow may not be extinct. More recently mainstream scientists, such as marine biologists Bret Weinstein and James Patton of the University of California have noted that there are vague reports of Steller’s Sea Cows from along the northwest coast of North America and the northeast coast of Asia, in the Arctic Ocean and Greenland. If such reports are not discounted, then Hydramalis gigas stelleri, or a subspecies, may still be alive today.

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  • : Le retour du tigre en Europe: le blog d'Alain Sennepin
  • : Les tigres et autres grands félins sauvages ont vécu en Europe pendant la période historique.Leur retour prochain est une nécessité politique et civilisationnelle.
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