On the 25th of June 2008 20 Magpie robins were flown to Denis on a chartered Twin Otter. 16 of the birds came from Fregate and 4 from the island of Cousin[1]. Translocation is a highly stressful experience for the birds and fatalities are not unexpected. The birds all arrived in apparently good condition however including the four from Cousin, which had experienced a sea crossing from Cousin to Praslin that morning prior to their flight to Denis.
A soft introduction method was utilised with the birds being kept by pairs in aviaries that were positioned in appropriately wooded and tranquil locations around the island. Veterinary expertise was on hand courtesy of the Durrell Wildlife Trust as Jersey Zoo, UK. The birds were released on a staggered schedule 2-3 weeks after arrival. Sadly one bird was lost whilst in captivity, a young female, that succumbed to a lung infection the type of which is linked to lowered immune response due to stress – i.e. most likely a casualty of the introduction process.
The released birds however, settled in very quickly, territories were soon formed and males could be heard singing from strategic vantage points high up in the casuarina trees.
Since their arrival the birds have received individual and dedicated care from Catherina Onezia, the GIF Project Officer. Catherina checks on the condition and activities of the birds and provides each territory with a special supplementary food mix 3 times-a-day.
The first egg was recorded on the 4th August and it hatched the on the 23rd! A fantastic start! Unfortunately the chick was later found dead below its nest possibly the victim of a Mynah bird attack.
By the end of December (i.e. 6 months after introduction) there had been a total of 13 nesting attempts recorded. 9 attempts failed:1 pullus was lost (as mentioned above) 2 nests were destroyed by Mynah birds the others failed at the nest building or egg stage. 4 were successful but two of the fledglings were lost – one due to an apparent abnormality with its legs and the other to unknown causes. So by the end of the year the islands population stood at 21 birds – an overall increase of 1. Compared to some past introductions elsewhere this was a very good beginning as a few birds can be lost in the early stages of an introduction before the population stabilises.
The number of nesting attempts is very encouraging and shows that the birds are in good condition and finding the habitat on the island suitable, but the number of failures in breeding is a cause for concern and certainly we need to investigate ways of improving the success rate. I have covered in detail (in my posts of 17th February and 17th March) the issues we are facing with the Indian Mynahs and how evidence is growing that they may be the main problem.
Catherina eventually had to take the injured chick (from the 17th February post) into fulltime care but the bird prospered there and has subsequently been released as an independent bird – the second chick Catherina has successful raised by hand!
At time of writing the island population now stands at 22 birds, including the loss of an adult to unknown causes, so there has been some additional breeding success this year. Let’s hope that we have turned a corner and that 2009 will be year of steady population growth! Keep checking back for updates…
[1] The SMR introduction was the result of a multi-partner cooperation in a project led by Nature Seychelles, supported by SMART (The Seychelles Magpie Robin Recovery Team – a multi-partner initiative) and in particular Fregate Island Limited.
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