Updated Sunday with Environment Authority reaction -
A species of rat has been spotted roaming in the wild in Malta, despite being endemic to central Chile.
Over the weekend, eagle-eyed citizens spotted and photographed the Chilean rodent, better known as the common degu, in woodland in Buskett.
But its presence is a more than just a bizarre sight: it’s a problem for local flora and fauna because it reproduces at a rapid rate.
Naturalist Arnold Sciberras, who works as a pest control consultant, said he believes they were most likely imported and then released but are now living in the wild.
Sciberras said he had first come across the degu in Malta as early as 2018 and since then had observed and trapped specimens all across the island – in Albert Town, the Marsa golf course, Wied Blandun, Corradino, Buskett, Girgenti, Wied l-Isqof and Wied il-Għasel.
It seems to be doing well in humid areas such as local valleys
“I’m of the opinion that the species will find it difficult to survive the summer heat, however it seems to be doing well in humid areas such as local valleys, owing to the fact that they have also managed to breed successfully in Wied Blandun,” Sciberras told Times of Malta.
“I really urge the public not to dispose of unwanted pets in the wild but contact societies, or even people like myself, so that we may aid in capturing and rehoming.
“Exotic species in the local habitat may die a cruel death, or even worse, live to thrive and decimate local species.”
The common degu (Octodon degus) is a small rodent endemic to the Chilean matorral ecoregion, roughly the size of a fancy rat – the type of rat bred for pets. They are strictly herbivorous and diurnal, meaning they are active during the day, however, in the height of summer they do not leave their burrows in the middle of the day as they suffer in high heat.
In recent years they have experienced something of a surge in their popularity as pets, due to their daytime habits as well as lifespan, which can reportedly stretch up to 13 years in ideal conditions.
Naturalist Alan Deidun said the presence of the degu could be problematic for local biodiversity.
“If the species is invasive it could have huge ecological and sociological repercussions on flora and fauna,” he said.
“When we set policy we usually do so to control invasive alien species that produce rapidly and displace the native species. In this case, the fact that it is a rodent is worrisome, because they reproduce at a very rapid rate.”
Environment Authority assessing the situation
In a statement on Sunday morning, the Environment Authority said it is assessing the situation.
"In line with the recently adopted National Strategy for Preventing and Mitigating the Impact of Invasive Alien Species (IAS) in the Maltese Islands, a rapid response process has been set up to assess the best way to control the spread of this invasive alien species in Malta, with particular reference to Buskett, in collaboration with other entities," the authority said.
"Whilst it is noted that some experts indicate that it might not survive the summer dry and hot climate of Malta, ERA is considering the precautionary approach. This is also considering the presence of humid valleys and areas with perennial springs in the Maltese Islands. Moreover, ERA notes that some species which were claimed as ‘difficult to establish themselves in Malta’ have now became invasive alien species in a number of areas in Malta and Gozo, including the Levantine Frog (il-qorru; iż-żrinġ l-għarib), the Red-Eared Slider (il-fekruna tal-ilma ħelu) and different Freshwater Crayfish (iċ-ċkala tal-ilma ħelu). These species are either escapees from the pet trade or were deliberately released or discarded into the environment,"the authority added.
It insisted that pets should never be deliberately released or abandoned into the environment, since many do not survive whilst others may not only thrive but become invasive, leading to considerable environmental and economic issues, with potential impacts to nature and biodiversity as well as agriculture and fisheries, amongst other sectors.