BRANTA — Stacey Melia
The effect of environmental conditions on Osprey chick diet
Institution: Aberystwyth University, UK
Supervisors: Pippa Moore
Details: BSc 2013 (Completed)
Subject Keywords: Osprey, diet, ecology
Species Keywords: Osprey, Pandion haliaetus
Thesis Online here
Abstract
The diet of an Osprey chick on the Dyfi estuary was examined in 2012 in order to assess the effect of environmental conditions on chick diet. Fish were identified using footage from nest cameras and biomass was determined using image analysis. Environmental conditions including cloud cover, rainfall, temperature, moon phase, wind direction, tidal depth, pressure and wind speed were recorded by staff and volunteers at the osprey project. The relationship between the conditions and diet was tested using DistLM and CAP multivariate analysis. Grey mullet (Mugil cephalus) was the most common fish delivered to the nest, with the average weight of all fish being 183.6g. Calorific requirements of the female and chick were only met on 30% of the days analysed, which may be attributed to the poor weather that season. The male osprey had a significant preference for foraging in the late morning and late afternoon/evening as well as between tidal depths of 1.5-2.0m and 3.0-4.5m. CAP and DistLM analysis showed the overall effect of environmental conditions on osprey chick diet to be not significant.