Compare And Contrast The Eurasian Falcon

The Eurasian curlew and the Peregrine falcon are two different bird’s species with noticeable anatomical and behavioral differences between them. While the curlew feeds from invertebrates, at the same time it becomes the prey for the falcon, which is conditioned by another feature of their anatomy, their beaks.
A decurved bill such as the one present in Numenius arquata has numerous advantages over a straight bill for such foraging on mudflats. Foraging Curlews use probing as a way to take their prey from the soil surface. Nebel, Jackson, & Elner (2005) define probing as a foraging technique that consists in inserting the bill into the sediment, allowing the capture of invertebrates that live below the surface (infaunal prey). Based on that, a bird with a decurved beak will be able to inspect …show more content…
(1986) argue that a bill with decurvature confers an element of surprise over preys such as worms, that have the ability to detect the presence of their predator. The bill tip of the curlew ends up closer to the feet so it is unlikely that the worm will be aware of the imminent attack. Also, for this bird is crucial to remove the worm from the substrate before swallowing it. However, that supposedly easy task can turn into a difficult one due to the anatomical structure of worms. They are fragile and easy to break, so it would take longer to grasp them and remove them broken in pieces than as whole ones. Usually, the bird pulls the worm’s tail first and then it moves, breaking the worm and leaving the thicker head end behind in the burrow, and with it more than half of the worm’s energy. In order to avoid that, when pulling a worm out of the mud, the bird must do it vertically and to a constant angle so the chance of breakage is reduced. The decurved structure of the bill of curlews (except in very soft mud), allows them to remove the bill from the insertion hole in a way that the part of the bill at the mud top is vertical (Davidson et al.,