Seasonal Trends and Factors Influence Osprey, Pandion haliaetus, Sightings in Port Everglades, Florida

• Main Author: Maurer, Sarah L.
• Format: Other/Unknown Material
• Language: unknown
• Published: NSUWorks 2006
• Subjects: Marine Biology; Oceanography and Atmospheric Sciences and Meteorology; osprey; Pandion haliaetus
• Online Access: https://nsuworks.nova.edu/occ_stuetd/110; https://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1292&context=occ_stuetd

This study analyzed non-breeding and wintering Osprey (Pandion haliaetus). Ospreys were surveyed from 2002-2005 along the Intracoastal Waterway in Port Everglades, Florida. The mean yearly sightings were 78 birds / yr. Sightings were not random and most frequent in the Upper-harbor, Mid-harbor and Dania Canal. There was no yearly difference in the number of Ospreys sighted. These results suggest a restoration project that removed all Australian pine trees (Casuarina equisetifolia) in a nearby state park appeared to have no impact on Ospreys in the area. There was a monthly difference in the number of Ospreys sighted, indicating that this area accommodated both migratory and residential Osprey. During the wintering season, October to March, sightings were at their highest. There was a difference in the sighting frequency of Ospreys based on perch type. Ospreys were perched more frequently in Red Mangrove trees (Rhizophora mangle) and on snags. There was a difference in the sighting frequency of Ospreys based on tidal state and water clarity. Ospreys were seen most frequently during low tide and most when water clarity was between 164-255 cm. There was a difference in the sighting frequency of Ospreys based on sky condition. Ospreys were seen most frequently on clear or cloudy days, although it only rained twice during the surveys, precluding statistical comparison to rainy conditions. Sixty four percent of the Ospreys in the Port Everglades area were males and 10% were females. Thirty one percent of photographed birds were individually identifiable. One individual observed on 14 occasions displayed site fidelity throughout the wintering season as well as between 2 yrs. No active nests were identified in the surveyed area of Port Everglades, therefore suggesting it is a possible important foraging and wintering area for resident and migratory birds.