The Seychelles Flycatcher (Terpsiphone corvina): whiskers, “hair-dos” and mimicry…

In my post of 9th April I wrote about the whiskers clearly evident on the faces of both male and female flycatchers (Terpsiphone corvina) and postulated on what their purpose might be. Whilst drafting that post I spoke to Rachel Bristol, Project Officer on the Flycatcher project. We talked about the whiskers and Rachel also commented on head plumage of the birds referring to it in her inimitable style as a “spiky hair-do”. Rachel subsequently sent me a wonderful photo of a male flycatcher in hand which clearly illustrates both features (see sidebar).

Then after her last visit to Denis, Rachel called to update me on her findings and mentioned something new of real interest namely that the Seychelles magpie robins (Copsychus sechellarum) in some territories had begun to imitate the song of the Flycatcher.

I have in the past written about the ability of Mynah birds to mimic the calls of the Seychelles magpie robin on Denis. The Mynah is a renowned mimic and I would not have been at all surprised if they had already begun copying the Flycatcher’s call and causing confusion in Rachel’s attempt to monitor the flycatchers on Denis. The Seychelles magpie robin is another matter and this is of particular interest because until the introduction of Flycatchers to Denis in November the two species had not co-existed on an island for a hundred years or more. This co-existence is therefore a new experience for the all the birds and also a time of great interest for ornithologists to see how the two species will interact. The feeding niche of the two species is largely distinct and their territories overlay each other on Denis without any evidence of negative interaction but the Magpie robins adopting the song of the flycatcher may conceivably lead to some confrontations in territories – at least in the short term

I was involved with the transfer of Magpie robins to Cousine Island in 1995. The overall population was much lower back then and the habitat on Cousine despite my efforts over the preceding year or two was still limited for the species. As such a very precautionary approach to the introduction was undertaken - two young surplus males from Fregate were introduced to the island and latterly an old male which had been displaced from its territory on Fregate and following injury had been nursed back to health by hand. These birds were surplus and somewhat expendable and the intention was to see how they fared on Cousine before any precious females would be risked. (The birds did settle and the old one ended up fathering more offspring when females were latterly introduced). Initially however what was remarkable was the very limited song variety of the young males. One of them just continually repeating the same three note refrain until it would put one’s teeth on edge! When the old male was introduced however he had an extensive variety of tunes suggesting that birds acquire/learn new songs over time and are not born with a pre-programmed repertoire. This thought was re-enforced when the younger males began to expand their own tune list once the old male had been introduced.

Now here on Denis nearly 15 years later we have further evidence of the capacity of the Magpie robin to learn new tunes and styles.