Newsletter / Blog
2012-01-06 Seychelles Warbler – A fantastic success story.
The Seychelles Warbler - Acrocephalus schellensis - has come
a long way from the days it neared extinction in the 1960s. The total world
population of 26 was found only on Cousin
Island, Seychelles.
Today this population numbers over 300 birds. From Cousin
Island, BirdLife International and
Nature Seychelles started
new populations, in line with the Species Action Plan, on Cousine, Aride, and Denis Islands
in order to secure the Seychelles Warblers long-term survival. Due to conservation
efforts there are more than 2500 of the species alive today.
The fifth island,
Frégate Island in the Seychelles has just received 59 Seychelles Warblers thanks
to a Nature Seychelles (BirdLife Partner) led initiative. The birds were
captured in the morning, transferred by helicopter and were released on Frégate
by afternoon of the same day so the birds could eat and drink before nightfall.
Fregate Island has been restored over many years
and is Rat and Mynah free which compete with and harm the Warblers.
The Seychelles
Warbler - Acrocephalus sechellensis - also known as Seychelles Brush-warbler is a Seychelles Endemic and naturally occur in dense
shrubland and in tall forests.
Description
It is a small
greenish-brown bird. It has long grey-blue legs, a long horn coloured bill and
a reddish eyes. The back, wings, flanks and head are greenish brown and the
belly and breast are dirty white. The throat is a stronger white and there is a
pale supercilium in front of the eye. Males and females look the same. Juvenile
birds are darker with a more bluish eye.
Call
Rich and melodious,
similar to a human whistle. Its structure is simple and is composed of short
song sequences delivered at a low frequency range.
Food
It is almost
exclusively an insectivore and obtains its prey by gleaning small insects from
the undersides of leaves. It does occasionally catch insects on the wing as
well. Most of the foraging occurs on Pisonia – Ficus lutea and Morinda – Morinda citrifolia. Studies of the foraging behaviour found that
Seychelles Warblers favour Morinda and spend more time
foraging there than in other trees and shrubs, the same study found that insect
abundance is highest under the leaves of that shrub. The planting of Morindaon Cousin, and the associated improved foraging for the warbler, was an
important part of the recovery of the species.
Breeding
The Seychelles
Warbler is a rarity in that it exhibits cooperative breeding, or allo-parenting.
The monogamous pair are assisted by a non-breeding female helper. Although
warblers can breed independently in their first year, some individuals remain
in their natal territory as subordinates, and often help by providing
nourishment to non-descendant offspring. The frequency of 'helping' is affected
by habitat saturation and variation in territory quality (insect prey
availability).
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