A medium-sized (58 cm) cinnamon-brown heron with a black crown and nape, Nycticorax caledonicus pelewensis is a nonmigratory subspecies of the Rufous Night-Heron that occurs only in the Palau and Chuuk islands of Micronesia (Pratt et al. 1987, Wiles 2005, Pratt and Etpison 2008). Its natural habitat is coastal wetland with mangroves for roosting and tidal flats for feeding grounds (Engbring 1988). The Rufous Night-Heron was selected as the flagship coastal species for Palau’s National Program for Monitoring Forest and Coastal Birds because it is a prominent feature of Palau’s coastal avifauna and, as a conspicuous territorial predator with a varied diet, it has practical value as an indicator of the biological richness of Palau’s coastal wetlands (Olsen and Eberdong 2012). In order to fully incorporate the Rufous Night-Heron into the national monitoring program, we needed a baseline population estimate for the Palau subpopulation. When we reviewed the reports of previous surveys of Micronesia’s birds (Engbring et al. 1990, Engbring 1992, VanderWerf 2007) we found that the reports mentioned sightings of Rufous Night-Herons but did not provide a population estimate. Waterbird Population Estimates (Wetlands International 2014) hazarded a “best guess” population estimate of “1–10,000” for the subspecies. The chief obstacles to establishing a more precise population estimate for the subspecies are the lack of a well-defined breeding season and the lack of centralized roosting or nesting colonies where the birds can be conveniently counted. Although Rufous Night-Herons are generally considered to be crepuscular or nocturnal creatures (Hancock 1999, Brazil 2009), we observed that, in Palau, they are routinely attracted to their coastal feeding grounds during daytime low tides. So we took the approach of a rapid field assessment of Palau’s Rufous Night-Heron population by counting the birds at low tide on their daytime feeding grounds as they stand on open tidal flats waiting for prey.