t’s not called the “African Galapagos”
for nothing. The island of São Tomé,
off the west coast of central Africa, is
truly one of a kind. For a start, it has
a remarkable level of endemism for such a small
island: 18 of its 126 bird species are confined to
that island alone. It is also unusual in that it has
no recorded human-driven bird extinctions – yet.
The island’s rugged landscape has protected
its bird population from human influence, but
this has proven a double-edged sword, making
it difficult to survey the island. And it does need
to be surveyed. Because, as every conservationist
knows, knowledge is power. We can’t conserve
a species unless we know where they live, which
habitats they prefer, what’s threatening them
and how many (or how few) there are.
What we do know is this. Among the island’s
18 endemic bird species, ten are classed as
globally threatened, with three listed as Critically
Endangered on the IUCN Red List: the Newton’s
Fiscal Lanius newtoni, Sao Tome Grosbeak
Crithagra concolor and Dwarf Olive Ibis
Bostrychia bocagei. These three species formed
the focus of an intrepid survey to discover more
about the secretive forests of this island.
I
4 0 Photos from the
expedition
Photo Hugo Sampaio
A selection of São
Tomé’s avian life.
Clockwise from top
left: Golden-backed
Bishop Euplectes aureus;
Red-headed Lovebird
Agapornis pullarius; Sao
Tome Paradise-flycatcher
Terpsiphone atrochalybeia;
Sao Tome Prinia Prinia
molleri; Newton’s Sunbird
Anabathmis newtonii;
Newton’s Fiscal Lanius
newtoni; Sao Tome White-
eye Zosterops feae (center);
Giant Weaver Ploceus
grandis
Photos Lars Petersson
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Prior to the survey, the Newton’s Fiscal and
Sao Tome Grosbeak were assumed to have a
population of fewer than 50 individuals. The
Newton’s Fiscal in particular was hardly ever
sighted: often, only its distant calls revealed it was
still there. The Dwarf Olive Ibis fared somewhat
better in terms of population size, but lost out
by being the only one targeted by hunters.
And hunters aren’t the only problem. Most of
São Tomé’s birds live in its forests – but these
are being encroached upon by human activity.
Records show that the island used to be entirely
covered in forest, but over half of it has been
cleared, mostly for crops, such as cocoa, coffee
and oil palm. Invasive species, such as feral pigs
or the Quinine plant Cinchona ledgeriana, have
also irrevocably changed the landscape. São
Tomé Obô Natural Park, home to most of the
island’s endemic species, offers protection from
apr-jun 2018 • birdlife
some of these threats, but not all.
And so, in 2016, a team of intrepid
conservationists including SPEA (BirdLife in
Portugal) and the RSPB (BirdLife in the UK) set
out to survey the island. It wasn’t easy. Surveyors
faced a range of challenges: despite the small
size of the island, torrential rain, mountainous
escarpments of up to 2,000m and venomous
snakes made the landscape hard to traverse.
Ricardo de Lima, lead author of the study,
describes the experience: “It was very intense.
We had a large team on the ground, sometimes
camping in the forest for over a week, carrying
tents, food and equipment on our backs, and
moving camp almost every night.”
But it was worth it, with the results shedding a
new light on these mysterious birds.
The findings were revealing and unexpected,
presenting both good and bad news, and
showing just how much scientists hadn’t
realised about the ecology of these species –
and of the forests as a whole. On one hand,
all three species were discovered in previously
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