Status and distribution of two diurnal raptors on the island of Grenada: Grenada Hook-Billed Kite (Chondrohierax uncinatus mirus) and Antillean Broad-Winged Hawk (Buteo platypterus antillarum)
| dc.contributor.author | Campbell, Ezra | |
| dc.contributor.examiningcommittee | Easter-Pilcher, Andrea (Natural Resources Institute) | en_US |
| dc.contributor.examiningcommittee | Kirkley, Jack (The University of Montana Western) | en_US |
| dc.contributor.supervisor | Koper, Nicola (Natural Resources Institute) | en_US |
| dc.date.accessioned | 2019-09-12T15:34:54Z | |
| dc.date.available | 2019-09-12T15:34:54Z | |
| dc.date.issued | 2019 | en_US |
| dc.date.submitted | 2019-08-28T18:40:43Z | en |
| dc.date.submitted | 2019-08-30T01:22:12Z | en |
| dc.date.submitted | 2019-08-30T13:24:55Z | en |
| dc.degree.discipline | Natural Resources Institute | en_US |
| dc.degree.level | Master of Natural Resources Management (M.N.R.M.) | en_US |
| dc.description.abstract | Habitat loss and fragmentation have had significant negative impacts on overall biodiversity, and led to a massive decline in the populations of numerous species around the world. Because raptors usually occur at low density and occupy large territories, they are sensitive to habitat degradation and loss. On the island of Grenada, located in the southern Caribbean Sea, two of the resident subspecies of inland diurnal raptors on the island include the Grenada Hook-billed Kite (Chondrohierax uncinatus mirus) and the Antillean Broad-winged Hawk (Buteo platypterus antillarum). Using a double observer approach, I surveyed these raptors using point counts and road transects surveys in both the wet season (June-November 2016) and dry season (January-April 2017). A total of 262 hawks were detected during the surveys, 70% (n=182) in the wet season and 30% (n=80) in the dry season; however, no kites were detected. I compared the fit of species distribution models using Maximum Entropy (MaxEnt) and generalized linear models (GLM) based on elevation and land cover using the road transects data. I modeled detectability of Broad-winged Hawks using N-Mixture modelling, and I determined whether time of day, day of year, land cover and elevation influenced detectability, abundance and availability using the point count data. My findings suggest that hawks are widely distributed on Grenada, contrary to the elusive kite. The probability of occurrence of hawks was best explained by elevation and land cover and not by season, and was highest in low elevation areas. Finally, the N-mixture models suggest that hawks are easier to detect earlier in the year, later in the day and in human-modified land cover classes. | en_US |
| dc.description.note | October 2019 | en_US |
| dc.identifier.citation | APA | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/34229 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Grenada | en_US |
| dc.subject | Raptors | en_US |
| dc.subject | Grenada Hook-billed Kite | en_US |
| dc.subject | Broad-winged Hawk | en_US |
| dc.subject | Species Distribution Models | en_US |
| dc.title | Status and distribution of two diurnal raptors on the island of Grenada: Grenada Hook-Billed Kite (Chondrohierax uncinatus mirus) and Antillean Broad-Winged Hawk (Buteo platypterus antillarum) | en_US |
| dc.type | master thesis | en_US |