Frequent, year-round monitoring reveals significant shorebird abundances in northern Manila Bay, Philippines

The connectivity of habitats along a migratory bird flyway is crucial for the survival of migratory shorebirds threatened by anthropogenic loss of coastline habitats. A lack of regular monitoring in shorebird sites may prohibit accurate and comprehensive assessment of site importance and impede the identification of key sites for conservation. Here, we present a case where important shorebird areas in northern Manila Bay, Philippines have been overlooked as previous counts were mostly made outside of the actual period of peak shorebird use. Areas surveyed, namely Tanza, Pamarawan and Pampanga, host high numbers of shorebirds during migratory months, with Tanza also having considerable numbers of over-summering shorebirds. Importantly, 14 species were recorded in abundances exceeding 1% of their flyway populations. These areas in northern Manila Bay should be granted protection under the Ramsar Convention on Wetlands, and demonstrate the importance of frequent, year-round monitoring in assessing sites. Unfortunately, northern Manila Bay is under grave threat as highly destructive development and land reclamation is currently being carried out, with additional coastal development projects planned. We highlight the urgency of surveying other sites in the Philippines to prevent inadvertent loss of undervalued shorebird areas and to preserve crucial portions of the East Asian-Australasian Flyway.