Passa ai contenuti principali

Asian relative of cane toad threatens Madagascar havoc

A relative of the cane toad, which has devastated wildlife in Australia, has invaded Madagascar, scientists report.
The Asian common toad was first seen on the island in March, and there have been several sightings since.
In a letter to the journal Nature, researchers warn that the arrival of the amphibian could cause "an ecological disaster" and wreak havoc on the country's unique fauna.
They say that urgent action is needed to remove the toads before they spread.
The fear is that the poisonous amphibians could poison local wildlife and carry diseases, such as the deadly chytrid fungus that has killed amphibians around the world.
One of the authors, Jonathan Kolby, of James Cook University in Queensland, Australia, said: "It's worrying because Madagascar has amazing endemic biodiversity - plants, animals and amphibians that are found nowhere else.
"And this one species has the propensity to damage that."
The amphibians were first seen in Toamasina, the main port of Madagascar. It is thought that they arrived in shipping containers from their native home in South East Asia.
"They are a very hardy and adaptable species," said Mr Kolby.
"They can handle a long ride on the ocean in a container, and then hop out wherever they end end up. And this is most likely how they got there."
The fear is that the warty brown creatures could repeat the damage that their relative, the cane toad (Rhinella marina), caused in Australia.
Cane toads, native to Central and South America, were introduced to Australia in the 1930s, initially to control pests, but they are now widespread and number in their millions.
They produce toxins that are deadly to the local birds, mammals and reptiles that prey on them and they have had a dramatic impact on the country's wildlife.
Asian common toads (Duttaphrynus melanostictus) are smaller than cane toads, but they are also venomous - and researchers think Madagascar's animals could be especially vulnerable.
"These animals have never been exposed to Asian toad toxins before and will likely not have an evolutionary defence against them," said Mr Kolby.
The 11 co-signatories of the letter add that the toads could outcompete other species and potentially spread the deadly chytrid fungus.
The researchers, from Australia, the US and Madagascar, say that conservationists and Madagascan government need to act quickly to eradicate the toads.
Mr Kolby said: "The question is, can we still eradicate them? Have we caught it soon enough that eradication could be a feasible option? Obviously we all hope the answer is yes."

Commenti

Post popolari in questo blog

Che cosa sono i Campi Flegrei?

  Le recenti scosse di terremoto hanno riportato l'attenzione degli scienziati sui Campi Flegrei. Che cosa c'è in quest'area? Perché si chiama così? Che rischi ci sono?     Campi Flegrei: rendering in 3D dell'area a partire da immagini satellitari fornite dalla NASA. I  Campi Flegrei  sono un'area vulcanica attiva che si trova in Campania, nel golfo di Pozzuoli e che include (completamente o in parte) i comuni di Bacoli, Giugliano, Monte di Procida, Napoli, Pozzuoli e Quarto. Il nome Campi Flegrei deriva dal greco, sta per "campi ardenti, in fiamme" e dà l'idea di come  questa zona sia stata caratterizzata fin dall'antichità da attività vulcanica . A differenza del  Vesuvio , spiegano all'Istituto Nazionale di Geofisica e Vulcanologia, i  Campi Flegrei  non sono un unico  vulcano , ma un campo vulcanico, attivo da oltre 80mila anni, formato da diversi centri vulcanici distribuiti su un'area depressa chiamata  caldera : quest'ultima ...

Londonderry explosion: 'Firebomb' explodes in Everglades Hotel

No-one was injured in the explosion but the reception area was extensively damaged A masked man has thrown what police have described as a "firebomb" into the reception area of a Londonderry hotel. The Everglades Hotel, in the Prehen area of the city, was evacuated after the device was reported at 23:15 BST on Thursday. The device exploded a short time later when Army bomb experts were working to make it safe. No-one was injured in the explosion but the reception was extensively damaged. Deputy First Minister Martin McGuinness has tweeted: "Derry is a place looking to the future and will not be held back by those living in the past. Their attack on the Everglades must be condemned." PSNI Chief Superintendent Stephen Cargin said: "A masked man went into the hotel and left a hold-all at the reception desk saying he was from the IRA. 'Ball of flames' The device exploded in the reception area of the hotel when Army bomb experts were wor...

Valkyrie, il robot della Nasa

Costruito sul modello dell'uomo, si muove con grande libertà e può valutare situazioni critiche. Valkyrie, il robot della Nasa. La Nasa lo ha tenuto segreto per più di una anno, da quando cioè, durante il  Darpa Robotics Challenge  dell’anno scorso, disse che stava lavorando al progetto di un robot umanoide, insieme a prestigiose università Usa, ma senza svelarne le caratteristiche. Ora eccolo: è R5 (Valkyrie per gli amici), alto un metro e 90, 125 kg, autonomia assicurata dallo zaino battery-pack. Più umani dell'uomo AL POSTO DI CHI?  Valkyrie parteciperà alla prossima edizione della sfida tra robot - il Darpa - con prove impegnative, come il camminare su terreni irregolari, salire una scala, utilizzare attrezzi e guidare un’auto: ecco perché è stato progettato con dimensioni e fattezze umane. L’obiettivo ultimo di questi oggetti ad altissima tecnologia è insomma quello di sostituire l’uomo là dove è necessario, in zone o condizioni di estremo pericolo ...