Spring Migration of Diurnal Raptors in Northern Luzon, Philippines, along the Oceanic Flyway in 2015 and 2016

Abstract

ABSTRACT Little is known about the spatiotemporal distribution of raptor migration in the Philippines. Located at the center of the East-Asian Oceanic Flyway, the archipelago is an ideal site to conduct raptor migration surveys. To augment knowledge of raptor migration in the region, we identified two watch sites and conducted surveys in spring 2015 and 2016 to determine the timing and abundance of raptors migrating through northern Luzon. We recorded 62,088 raptors in 2015 at Pagudpud, Ilocos Norte, over 34 survey d, and 36,443 raptors in 2016 at Sanchez Mira, Cagayan over 25 d. Grey-faced Buzzards (Butastur indicus) and Chinese Sparrowhawks (Accipiter soloensis) dominated the counts. The relatively low abundance of migrants compared to other sites along the flyway, and variation between our two count sites/years partly reflected the influence of variable and relatively limited survey periods and effort. Despite this limitation, we gained important insights about migration routes and timing in this part of the East-Asian Oceanic Flyway. Preliminary data on migration patterns are important to understand migration strategies. With additional data, we can build models of route and habitat suitability and use them for species and habitat conservation.