From the Trinidad and Tobago Field Naturalists’ Club Facebook page (check it out for more info on T&T’s natural history):

The pygmy kingfisher (Chloroceryle aenea) is Trinidad’s smallest kingfisher. It can be found in a range of environments but always near water, including mountain streams, mangrove swamps and marshes. They feed on small fish, insects and other small prey items. While difficult to detect when perched, pygmy kingfishers will usually vocalize when in flight.