In recent days at Las Catalinas, in Central Park, we have witnessed how the two retention ponds, originally built to slow down rainwater runoff into the creek and filter sediments, reducing erosion and the impact of heavy rains, have also opened the door to new surprises as nature has found its own way to respond.
Thanks to this month’s rains, which have painted the landscape green, we have discovered unexpected visitors: the black bellied whistling ducks (Dendrocygna autumnalis), known as "piches" or "pijijes" in Spanish. These striking birds have a coral colored bill, chestnut body, black belly, and wings with a white patch visible in flight, and they usually live six to eight years in the wild.
Its distribution extends widely from the southern United States through Mexico and Central America into South America, with notable populations in Guanacaste’s Palo Verde and other Costa Rican wetlands. In Costa Rica it is common in lowland wetlands such as the Tempisque basin, shallow lagoons and flooded grasslands. Spotting them in a tropical dry forest, however, is less usual and is made possible here thanks to the presence of our ponds.
Highly social, these ducks gather in noisy flocks and are known for their distinctive whistling call in flight, a sound that is impossible to miss when they rise together at dusk. They feed both during the day and at night, searching for seeds, grains, aquatic plants and occasionally insects and crustaceans.
Seeing them in Las Catalinas is not particularly rare, but it is a clear sign that created habitats, even when artificial, can quickly become part of local ecological dynamics. While the original goal of the ponds was to manage water flow and sediment, nature has taken hold of them in its own way.
Today these whistling ducks have found a new place to feed, rest and perhaps even nest, a reminder of how the infrastructure in Town can also host life in more ways than we can imagine.