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Conservation >
Birds
Ongoing Projects:
Sooty Terns
White-tailed Tropic Bird
List of
Birds recorded on Bird Island
Sunbirds
Migrant Waders on Bird Island
More migratory species of birds have been recorded on Bird Island,
compared to any other island in Seychelles. This is partly because of
the geographical location of the island at the northern edge of the
Seychelles plateau
 and partly
because of a long tradition of recording
observations by staff of Bird Island Lodge. It has been conjectured that
some may be the same individuals
returning in consecutive seasons. For example rarities including
Oriental Pratincole Glareola maldivarum
and Stone Curlew Burhinus oedicnemus have over-wintered in recent
consecutive seasons, birds showing a strong site fidelity to a
particular location on the island on each occasion. In the early 1980s,
Ruddy Turnstone Arenaria interpres colour-ringed on Cousin by NJ
Phillips were re-sighted in subsequent winters. One ringed on Cousin in
November 1982 was recovered in Kazakhstan in August 1986 and again
recovered on La Digue in November 1986. There have
also been ringing recoveries from Cousin in Iran and Dagestan (Skerrett
et al. 2000).
Robby Bresson and Margaret Norah decided to conduct a study of Ruddy
Turnstone on Bird Island, the most common migrant. RB,
Conservation officer on Bird, started field work at the beginning of
March 2004 recording our observations in the hope that obvious patterns
would emerge. The gap in the figures January 2005 is when RB was away
from the island on annual leave.
There are Ruddy Turnstones on the island throughout the
year. It is believed that those that remain during the breeding season
for the species are juvenile or non-breeding birds as none change into
adult breeding plumage. RB in his daily observations records migrants as
a matter of course and MN records for analysis the highest number seen on any one day during that week. The graph
below shows the counts for Ruddy Turnstone in 2004 and 2005.
Based on
the graph above we thought it would an interesting exercise to ring a
sample of Turnstones to see if ‘our’ turnstones were coming back to us.
RB netted nineteen Ruddy Turnstones
at random between 31 March 2005 and 12 May 2005. All were in full summer
breeding plumage indicating that they were preparing to leave the island
for their breeding grounds. A blue plastic
ring was placed on the left leg and a numbered ring on the right leg.
Daily observations showed that by the end of May all ringed birds had
left the island. Over the years it has been observed that by the end of
May all Ruddy Turnstones in summer plumage have left the island and this
year was no exception.
From the end of August RB searched for the ringed birds to test the
theory that the same birds return year after year. The first week of
September showed the first marked increase in migrants generally. On 13
September Robbie saw the first Ruddy Turnstone with a blue ring.
Over the next couple of weeks he recorded a further thirteen, the total
number of resightings representing 74 percent of the original sample.
The returning birds were not re-trapped, and so we do not know which
individuals out the 19 original ringed returned. In addition to ringing
Ruddy Turnstones, a Whimbrel
Numenius
phaeopus
was ringed with both a metal and a black plastic ring in the Sooty Tern
colony in April (before the Sooty Terns
Sterna fuscata
arrived, when access to the colony is no longer possible). It was not
seen after May and reappeared on 19 September,
once again in the Sooty Tern colony.
In September RB began ringing a new sample of Ruddy Turnstones this time
with a white coloured ring to indicate a new season and will continue
over the next two or three years to put a different coloured ring each
season. Hopefully over the next few years our observations will show
that a significant proportion of migrants are faithful to their wintering
site on Bird Island.
References
Skerrett,
A. and the Seychelles Bird Records Committee 2000. Ringing Recoveries
from Seychelles. Birdwatch 37: 19-21.
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