Right before Marciel and Ernesto came along, I'd been rather abstractedly communing with the pond ecosystem, and more than once just a few feet away I'd heard a small splash as if someone had tossed a pebble into the water. When I'd looked in that direction, however, what I'd seen had been a little Green Kingfisher the size of a Hairy Woodpecker flying away. You can see a Green Kingfisher at http://www.worldbirdingcenter.org/bird_info/green_kingfisher.phtml.
Green Kingfishers are a little more than half the size of North America's Belted Kingfisher. Anyone used to the Belted's spectacular splatterings when diving for fish will be struck by the Green's much more modest little ker-plunk. It's clear that the physics of a small bird diving into water differs a lot from that for a big one. It's as if water becomes thicker for smaller birds, and therefore harder to penetrate. If you extrapolate the concept on downward you come to insects walking atop water.
Green Kingfishers are by no means Mexico's smallest kingfisher species. The Green is ±7.5 inches long but the Pygmy of southern Mexico and the Yucatan is only ±5.5 inches (20 & 13 cm, respectively). At Río Lagartos occasionally I saw Pygmys in the mangroves. Mexico is home to five kingfisher species, and one, the Ringed, is noticeably larger than the Belted common in much of North America. Our Green Kingfisher occurs from southern Texas all through Mexico and Central America to northern Chile and Argentina. Along the Amazon's steamy banks the Green Kingfisher is hard to miss.
Actually, relative to the rest of the world, the Kingfisher Family is poorly represented in the Americas, which hosts only six species. The part of the world richest in kingfishers is the Australasian Region, followed by Africa and Asia. Not all kingfishers dive into water for fish. At http://animaldiversity.ummz.umich.edu/site/accounts/information/Alcedinidae.html I read that "About 44 species live in closed-canopy forests (primary and secondary), 17 species in wooded savannas, and 31 species in aquatic habitats including seashores, mangrove swamps, lakes, rivers and streams. One species lives in desert scrub."
There's a lot of life-history information about kingfishers at the above address, too.