Endemic island birds are more vulnerable to extinction through anthropogenic factors than any other avian group. At least 90% of the species of birds that became extinct between 1600 and 1980 were island endemic and almost 40% of todays endangered bird species are confined to island. The endemic Seychelles Magpie Robin ( Copsychus sechellarum ) is no exception to the rule. This ground dwelling black and white chat is currently among the most endangered birds in the world. The critically endangered Seychelles Magpie Robin is the largest and a morphologically distinct member of the predominantly Asian genus within the Muscicapidae family or flycatcher group.
The granitic archipelago of Seychelles in the Western Indian Ocean has a relatively rich avifauna considering the small size and isolated position of the islands. The Magpie Robin has a low reproductive rate with a clutch-size of one. However, this is offset by it’s longevity; the oldest Magpie Robin on record was 16 years old. Nesting frequency seems to be correlated to food availability and under favourable conditions, three chicks may be produced by a pair in one year. Most nesting attempts occurs during the wet season which is between October and April when invertebrate abundance is higher. Nest building and incubation last for 16-20 days. Most males display nest-guarding behaviour throughout incubation period and nest-rearing. Magpie Robins are strongly territorial forming groups of up to 6 individuals with only one breeding pair. Dispersing juveniles are frequently accepted and unrelated sub-ordinate adults might be tolerated.Therefore groups are not strictly a family unit but nevertheless they usually all assist defence of territory against intruders. They are primarily ground-feeders spending more than 90% of their foraging time on the ground. Invertebrates account for 96% of their diet, including centipedes, millipedes, spiders, small scorpions and ground-dwelling insects such as cockroaches and woodlice. Here on Aride island, where I am currently interning, the Magpie Robin is on the brink of disappearing with only 8 magpie robins left. Conservation measures are being taken by Miss Licia Calabrese, the island’s expert on magpie robins since she did her thesis on them a few years back. Modified pitfall traps, are used to monitor insect abundance in different territories and they are simply cut up bottles placed in the ground and a rock with a ribbon is placed on top; after a week they are collected and the earth samples are monitored to see how many cockroaches are found ( a very face-cringing job!) Colour-ringing and caring for young chicks are old conservation techniques that have been on the go for quite a long time now. Island Conservation Society seems to be planning on re-introducing land giant tortoises back onto Aride but ecosystems surveys have yet to be carried out. Giant tortoises increase the feeding rate of the magpie robins greatly as prey (such as cockroaches and woodlice) are exposed on the disturbed soil. However, these tortoises could cause havoc with wires and pipes and they may dirty and use up the scarce water sources. This is why personel will need to analyse the outcome before they go through with the experimental attempt. Sarah Purvis
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AuthorThe interns of the Prosperity & Environment: Promoting sustainable development opportunities for youth in the Blue Economy sector. Archives
January 2018
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