ENDANGERED SPECIES IN THE DOMINICAN REPUBLIC
Ecology and Conservation of Threatened Avifauna in Two National Parks
The Dominican Republic is home to 30 species of birds found nowhere else in the world. Unfortunately, 19 of these are in danger of becoming extinct. As forest is cut down to produce charcoal or create more farmland, there is less and less habitat for these birds. Today, less than 10 percent of the native forest remains.
WPC's 2004 Canadian Collection recipient, Lance Woolaver, is studying the ecology, distribution and breeding biology of seven of these rare species within the Sierra de Bahoruco and Los Haitises National Parks.
As part of a three-year PhD. research project, he's looking at the baybreasted cuckoo, hispaniolan parakeet, hispaniolan parrot, plain pigeon, grey-headed quail-dove, white-necked crow and Bicknell's thrush. However, his top priority is the critically endangered Ridgway's hawk.
RIDGWAY'S HAWK
Buteo ridgwayi
Original range | Current range | Estimated population | Threats to survival | Species recovery | Species recovery | Partners and links
Description: This small, elegant forest raptor is the most endangered hawk in the Caribbean. It is brownish-grey on top and grey underneath, with a black and white barred tail. Males also have reddish thighs.
On average, Ridgway's hawks measure between 36 and 41 cm long, and females are somewhat larger than males. They live in undisturbed forest, feeding on small mammals, birds, lizards and snakes and nesting in the crown of tall trees.
Original range: These hawks were once widespread throughout the Dominican Republic and Haiti.
Current range: In the Dominican Republic, they are now restricted to an area of just 120 square kilometres in the lowland rainforests of Los Haitises National Park. There have been very few recent sightings outside this area.
Estimated population: Today, there are fewer than 50 hawks.
Threats to survival: Ridgway's hawk faces two main threats: pressure to convert the national park into agricultural land, which would destroy its vital habitat, and the risk of being shot by local people.
Species Recovery: Lance and his wife, Rina Nichols (now WPC's Species Recovery Biologist), monitored six pairs in Los Haitises National Park throughout the 2004 breeding season with the help of six local biologists. This was the first time that nests had been monitored since the species became endangered. All six pairs tried to nest, but didn't succeed at fledging any young. Three nests failed during incubation, and three after hatching.
In 2005, Lance monitored 22 nests and collected DNA samples from adult birds to determine the degree of inbreeding and loss of genetic variation in this very small remnant population. Adult and juveniles were colour banded for long term monitoring, and a community education program was launched to make local people aware how rare and unique this hawk is.
Learning the basic biology of a rare species - nesting, feeding and breeding - is key to helping conserve it. And once we know more about it - what its ecological needs are, and why the population is declining - then we can determine what needs to be done to help the species rebound, and put that into action.
For continuing updates, see the field reports on the right of this page. To download Lance's Progress Report 2005, click here.
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