Saving the Seychelles
From mid-May to late August this year, Don Merton and a small team of fellow New Zealanders worked to eradicate rats, cats and mice from Denis, Curieuse and a neighbouring 219 hectare island in the tropical Indian Ocean group. The pests were threatening to wipe out endemic birds, reptiles and insects, including two high profile bird species, the Seychelles magpie robin and the Seychelles fody. The trip was a result of Merton’s earlier work in the Seychelles which had brought his skills to the attention of its government. The first was in the early 1990’s when he helped BirdLife International rescue the magpie robin, then down to about 20 individuals. His management techniques are credited with helping bring the species back from the edge of extinction and there are now more than 90 birds. The bad news, he says, is that rats recently invaded the key island refuge. Then, in 1996 Merton, an internationally known conservationist, again took leave from the Department of Conservation to run a successful rat and rabbit eradication project on Bird Island, most northerly of the Seychelles group. These visits lead the Seychelles government to ask him to carry out an eradication feasibility study as part of its national strategy for restoring island biodiversity. The study was completed in 1998 and this year’s operation was the first step in making it happen. For Merton, it was an opportunity to help prevent a repeat of the nightmare he witnessed on Big South Cape Island, near Stewart Island nearly 40 years ago. In 1964 that island, valued as the final refuge for many southern New Zealand species, succumbed to an irruption of ship rats. In what has been billed one of the worst ecological disasters in New Zealand’s recorded history, the then Wildlife Service made a desperate bid to save the Stewart Island snipe, Stead’s bush wren and greater short-tailed bat, but sadly all were exterminated. Fortunately, Merton and colleagues were successful in saving the South Island saddleback from imminent extinction. Merton says that this time the efforts appear to have come in time and extinctions have been averted. The Kiwis worked through a great many challenges to complete the task. These included high temperatures, having to confine several hundred individuals of four resident threatened species for three months, some residents removing bait for their personal use and passive resistance by some local Hindus who opposed the killing of pest animals. For a country facing major economic difficulties, where cigarettes were rationed to one per customer until they ran out completely, island restoration is ordinarily a low priority. However, Merton says rat populations had reached the point where they were impacting on the country’s key industry, tourism. Rat infestations were driving people away. Only time will tell whether they have successfully eradicated the target pests. If so, rat-free habitat available to sensitive endemic animals will have been increased several-fold, from about 280 hectares on a handful of tiny islands to more than 1,000 hectares © Marieke Hilhorst/ORIGIN NATURAL HISTORY MEDIA |