Grenada, West Indies
Abundance & distribution of Grenadian birds
Grenada is host to many species of passerine birds, but to date, few studies have examined the abundance, distribution and behaviours of birds living in Grenada. This means that for some endemic species, such as the Lesser Antillean tanager, Tangara cucullata, very little is known about their true conservation status. A key issue in conservation is the need to detect and monitor vulnerable species. We need to establish baseline data and a population monitoring program for birds in Grenada focusing on endemic and restricted-range species, especially because the country is undergoing rapid building and development.
I collaborated with Dr. Nicola Koper at the Natural Resources Institute, University of Manitoba. Together we co-advised Ramon Williams (M.Sc) and his team of citizen-science volunteers. In 2018, we surveyed all Grenadian resident avian species in order to establish baseline abundance and distribution data, and to determine the impact that increased human activity and urbanization has on the distribution and abundances of all resident land-birds, including restricted range and endemic species. Our preliminary analysis has shown that endemic species are utilizing different habitat types than more widespread species, demonstrating that conservation of a mosaic of different habitat types is necessary to maintain avian diversity in this small island developing nation. Furthermore, we have found that urbanized land-use areas (but not small- scale organic farming) significantly decreases avian diversity and habitat occupation by many species.
Our results were published in the Journal of Caribbean Ornithology: Avian use of anthropogenic and natural habitats in a Small Island Developing State.
Ramon Williams, B.Sc., M.Sc.
Photographs: Joshua Yetman, St. George's University;
Image: Miya Warrington
Polymorphism & cline characteristics of bananaquits
The bananaquit, Coereba flaveola, is a well-studied bird found in the Caribbean region. A literature search on the “Web of Science” using the search terms ‘bananaquit’ reveals 88 different articles, ranging from studies of genetics, melanism, breeding ecology, foraging and distribution. In Grenada, other than the Grenada Dove, the bananaquit has been the most studied bird species. It has been studied in regards to the melanism, genetics, and breeding ecology. The bananquit has two morphs a "yellow" and a "black" and interestingly, the black morph only exists in Grenada, St. Vincent and two small islands of the coast of Venezuela. The colour morph ratio was previously studied in the 1980"s by Joseph Wunderle Jr, as well as a short study on colour morph in the southern end of Grenada in 2003 (MacColl, A. D. C., & Stevenson), In conjunction with Ramon Williams and students from the SGU Education, Conservation and Outreach (ECO) organization, we examined the stasis of the colour morph cline and possible acoustic and behavioural mechanisms that may drive the stability (or dynamism) of the cline.
Photographs (left): Joshua Yetman, St. George's University; (right): Miya Warrington