Red-billed tropic birds. (Hannah Madden photo)
Bridled quail-dove. (Hannah Madden photo)
ST. EUSTATIUS–Around 250 researchers, scientists and bird enthusiasts recently travelled to Cuba to participate in BirdsCaribbean’s 21st Regional Meeting, an event that is held every two years.
Among the participants was St. Eustatius’ Hannah Madden, who has been studying the island’s birds since 2008.
Birds in general are an important indicator of the health of their surroundings, and for that reason they are often used in research to measure the impact of specific actions or changes in the environment.
Representing Ecological Professionals Foundation, Madden presented an assessment of the reproductive ecology of the red-billed tropicbird, a migratory seabird that nests on Statia.
Analysis of the data indicates that reproductive success is affected by elevation, whereby nests at lower elevations are more susceptible to failure than those at higher elevations. This could be linked to predation of tropicbird eggs by invasive black rats, however, additional data are required to quantify this. Madden will collect these data in 2017 and 2018 by implementing rat control at the Pilot Hill site and analysing nest success.
She gratefully acknowledged field assistance by rangers, interns and volunteers of St. Eustatius National Parks Stenapa during the study.
Madden’s cost to attend the conference was donated by NuStar Terminals NV, who also provided funds to study the foraging ecology of this species. A copy of the research will be shared with Stenapa, NuStar, and other relevant stakeholders upon publication.
Representing Caribbean Netherlands Science Institute (CNSI), Madden presented the results of a population assessment of the bridled quail-dove, which was recently conducted under a rat control project, funded by the Ministry of Economic Affairs.
The bridled quail-dove is a regionally endemic species that is thought to be declining on islands where it still exists. On Statia it is only found in the dry forest of the Quill at elevations of 150 to 600 meters, and the majority of the population is clumped into an area of around 165 hectares.
There are estimated to be between 560 and 1,620 individuals based on the 2017 survey, which was conducted in May with Frank Rivera-Milan of the United States Fish and Wildlife Service.
The survey will be repeated in 2018, and the data compared, hopefully resulting in an increase in the island’s quail-dove population following rodent control in the Quill.
Madden recently became a board member of BirdsCaribbean, an organization that is dedicated to the study and conservation of Caribbean birds. She has been an active member since 2012.
Despite its small size, Statia supports regionally important populations of increasingly vulnerable bird species, and Madden remains passionate about researching and promoting the island’s avian fauna.