Frogs’ fluorescence, why?


This video says about itself:

17 March 2017

A group of Argentine and Brazilian researchers has discovered the first case of natural fluorescence in amphibians, in a species of tree frog that is frequently found in South America.

From Science News:

First fluorescent frogs might see each others’ glow

Natural Day-Glo may play a role in amphibian’s fights and flirtations

By Susan Milius

10:00am, April 3, 2017

Could fluorescence matter to a frog? Carlos Taboada wondered. They don’t have bedroom black lights, but their glow may still be about the night moves.

Taboada’s question is new to herpetology. No one had shown fluorescence in amphibians, or in any land vertebrate except parrots, until he and colleagues recently tested South American polka dot tree frogs. Under white light, male and female Hypsiboas punctatus frogs have translucent skin speckled with dark dots. But when the researchers spotlighted the frogs with an ultraviolet flashlight, the animals glowed blue-green. The intensity of the glow was “shocking,” says Taboada of the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” in Buenos Aires.

And it is true fluorescence. Compounds in the frogs’ skin and lymph absorb the energy of shorter UV wavelengths and release it in longer wavelengths, the researchers report online March 13 in Proceedings of the National Academy of Sciences. But why bother, without a black bulb? Based on what he knows about a related tree frog’s vision, Taboada suggests that faint nocturnal light is enough to make the frogs more visible to their own kind. When twilight or moonlight reflects from their skin, the fluorescence accounts for 18 to 30 percent of light emanating from the frog, the researchers calculate.

Polka dot frogs, common in the Amazon Basin, have plenty to see in the tangled greenery where they breed. Males stake out multilevel territories in vast floating tangles of water hyacinths and other aquatic plants. When a territory holder spots a poaching male, frog grappling and wrestling ensues. Taboada can identify a distinctive short treble bleat “like the cry of a baby,” he says, indicating a frog fight.

Males discovering a female give a different call, which Taboada could not be coaxed to imitate over Skype. The polka dot frogs’ courtship is “complex and beautiful,” he says. For instance, a male has two kinds of secretion glands on the head and throat. During an embrace, he nudges and presses his alluring throat close to a female’s nose. If she breaks off the encounter, he goes back to clambering in rough figure eights among his hyacinths, patrolling for perhaps the blue-green ghost of another chance.

New national parks in Argentina


This 2014 video, in Spanish, is called Mar Chiquita, Miramar Córdoba.

From BirdLife:

14 March 2017

Argentina will have two new National Parks

At the stroke of a pen, the largest saltwater lake of South America, Mar Chiquita, and the nearby Estancia Pinas are now set to become National Parks.

Clouds of up to half a million phalaropes cover the sky, almost blocking the sun. The horizon then turns pink with over 100,000 Chilean flamingo Phoenicopterus chilensis living and nesting there. The gold of the grasslands, protecting the enigmatic maned wolf Chrysocyon brachyurus, is so bright it makes your eyes squint. The water covers everything as far as the eye can see, but the sounds and colours of the birds stand in a festival for the senses capable of moving any human being: Mar Chiquita is a true “sea of ​​nature”.

This is the daily life at Mar Chiquita and the Dulce River, the largest salt lake in South America, a Wetland of International Importance according to the Ramsar convention and one of the five Important Bird Areas (IBAs) in danger of Argentina.

A few years ago Aves Argentinas (BirdLife in Argentina) set out to work to achieve the effective conservation of many of its IBAs, especially those categorized as “in danger”. This was the case 3 years ago with Buenos Aires Lake, fundamental for the future of the Hooded Grebe Podiceps gallardoi, which today is largely covered by Patagonia National Park.

The time has now come for Mar Chiquita. Although currently listed as a Multiple Use Reserve it has several problems of forest clearing, unplanned use of water resources and tourism, and illegal hunting that affect it negatively. This is why Aves Argentinas, with the objective of turning it into a National Park, began work in the area, identifying fiscal areas that could be joined to the protected area and getting donors for eventual land purchases. Local actors, researchers, environmental educators, the Bird Watchers Club and villagers were all involved in the process. Little by little, the idea of a National Park took shape and strength.

The provincial and national governments then became enthusiastic about the project. The National Park Administration gave its approval and on Monday March 6 all parties signed an agreement to begin work on the creation of the new National Park – which could exceed 700,000 hectares and so will become the largest National Park in Argentina.

It will become one of the most important national protected areas as it includes some of the most densely populated sites for birds in the country. It will undoubtedly become a favourite for birdwatching tourism in particular – which today attracts more than 40,000 foreigners each year to Argentina.

In a region that has been left behind, the new National Park is also a possibility for economic development. Within the framework of this agreement, Aves Argentinas integrates an advisory committee together with the local organization Yaku Sumaq and representatives of the Austral University.

Undoubtedly it might bring as well an auspicious future for migratory birds: shorebirds such as the Wilson’s Phalarope Phalaropus tricolor, Red Knot Calidris canutus, Hudsonian Godwit Limosa haemastica or the American Golden Plover Pluvialis dominica congregate there in large numbers.

In the northern grasslands there are rare and little-known species such as Dot-winged Crake Porzana spiloptera, Sickle-winged Nightjar Eleothreptus anomalus or Bay-capped Wren-spinetail Spartonoica maluroides.

In the few pieces of the Chaco plains that remain on the southern and eastern edges of the lagoon – the areas most affected by the advance of agriculture – there are still birds threatened by wildlife traffic such as the Ultramarine Grosbeak Cyanoloxia brissonii and even some of the rarer Yellow Cardinal Gubernatrix cristata.

In addition to the big news, the agreement signed between the national government and the province brought another round of good news as it also establishes the joint work for the creation of another new National Park in Estancia Pinas, a 100,000 hectare site of dry chaco plains in the west of the Córdoba province (central Argentina).

In this site we can find populations of Chaco Eagle Buteogallus coronatus, among many other bird species, and the last populations of guanacos Lama guanicoe of the province. Furthermore, populations of the recently discovered Chacoan peccary Catagonus wagneri, an endangered species that was believed extinct until decades ago.

As Aves Argentinas celebrates its centenary, the BirdLife community rejoices the good news – the result of years of hard work. Without a doubt, great news for people, birds and nature.

Conserving the natural grasslands of South America. As agriculture, forestry, roads and urbanization brought economic development to the vast grasslands of South America, the area of this important ecosystem was reduced by half. Luckily, ranchers and conservationists are joining forces to save these vital lands: here.

World’s first fluorescent frog discovered in Argentina


This video says about itself:

14 March 2017

World’s first fluorescent frog that glows bright green is found in Argentina

Under normal light the polka-dot tree frog is a dull green/brown colour.

But scientists stumbled upon the species’ rare ability under their UV torches.

It is rare for land animals to have fluorescent skin pigments.

The pigments absorb light and re-emit it at longer wavelengths.

Read more here.

See also here.

Scientific description of this new discovery about Hypsiboas punctatus frogs: here.