by Mervin Matthew,
Government Information Service
 Live mountain chicken
Forestry officials here are working with counterparts at the Zoological Society of London to determine the cause and eventually bring an end to the crisis which resulted in a significant decline in the population of the island’s mountain chicken.
Professor Andrew Cunningham of the Zoological Society of London has been monitoring the decline of the crapaud population since it began in 2002.
He explained to GIS News on Tuesday that due to the unique nature of this species of frog researchers are very concerned about the declining population.
“The mountain chicken is a really important species. It is the second largest frog in the whole world and has an amazing life cycle. The reproduction of this frog is unlike any other species. The female will prepare a full nest in a burrow in the ground and she lays her eggs in that next. When they hatch, the tadpoles stay underground in that next and the female comes and feed the tadpoles with infarcted eggs that she passes herself. When they metamorphose and turn into small frogs, the female continues to look after them for a number of days after they leave the burrow. So this is a really interesting reproductive strategy but the mountain chicken, being one of the largest frogs in the world, is a very important predator of invertebrates on Dominica and in Montserrat. They feed on a huge number of crickets and millipedes and agricultural pests. Therefore, they are a very important for the ecology of the island and for human wellbeing as well.”
Early in 2002 dead crapaud were found in various parts of the island and their friendly calls slowly faded. After extensive examinations researchers determined the cause of their deaths.
 Professor Andrew
Cunningham of the
Zoological Society of London
“A fungus, called Chytrid fungus, appeared to have been introduced into Dominica. We do not know how it got here but it started to kill the crapaud. By 2004, the population of crapaud on Dominica had declined by over eighty percent (80%). So, only two in ten animals are left alive. Since 2004, that decline continued at least until a couple of years ago to the point the animal was almost completely wiped out across the whole island.”
The Chytrid fungus however did not only affect the crapaud population.
“This fungus is causing problems for other species of amphibians across the world; in North and South America, Africa, Australia and in Europe, this fungus is spreading. We think it started to spread in the 1960’s and it has been causing many different species of frogs and toads and salamanders to decline. It kills them and the populations decline very rapidly. We think about a hundred species have gone extinct in the last twenty to thirty years purely because of the spread of this fungus.”
Researchers are still trying to determine how the fungus was introduced into Dominica’s forests.
 Effect of Chytrid fungus on frogs
“There is quite a lot of research going into that not just with the mountain chicken but with other species that have been hit hard with this fungus. Some species of frogs do not appear to be affected by the fungus and the ‘gounouge’ here in Dominica is one of those species (those little tree frogs). They are as numerous as they have ever been on the island and yet we know they can be infected by this fungus. Indeed, some of them seem to be carriers of the fungus so they are infected but not killed by it.”
In an effort to replace the dying crapaud population a captive breeding programme has been introduced at a special facility within the botanic gardens.
“From here, the main thing is to see if we can breed the animals in captivity in Dominica and if we can, we will then start a release programme similar to the one that has, so far, at least been successful in Montserrat. But this time, we will be using captive bred animals from within the country rather than bring them back from overseas. They will be Dominican frogs through and through and we will then be releasing them, assuming that we are successful in breeding, back into their natural habitat on the island. The animals will be tagged with a transmitter so that we can follow them knowing where they go and how they survive. If they do get infected by the fungus, we should be able to detect if that is happening or if they are able to survive or if they move to new areas, we should also be able to detect if that is happening. But, this is someway into the future because at the moment we still have to breed the animals here in Dominica.”
It is difficult to determine when the crapaud population will once again begin to live within the island’s forests but Professor Cunningham is confident that it will happen.
“It is a very iconic species for Dominica. What will the Nature Isle be like without its nature? It is really important that we all make a big effort over the next few years to conserve the species and hopefully try to get the numbers back up through captive breeding, through protection in the wild and so on so that one day again, people can eat the national dish of Dominica. But that is not going to happen for a little while I am afraid.” |
