Palo Verde

Palo Verde is a national park located at the mouth of the Tempisque River. There is a big marsh here that is important for migratory birds. The marsh has an interesting management story. Until the 1970's, the area was a ranch and cows grazed in the marsh. When the land became a national park, the cows were removed. The entire marsh became covered with cattails within 10 years. Cattails are native to the area, but they take over without grazing. The current theory is that the cattails used to be controlled by the frequent flooding of the river, but the river has been altered so much that it rarely floods. Since around 2000, the park has been using cows to graze the marsh and a tractor to crush the cattails to open up the marsh. Anyhow, the marsh is now filled with jacanas, whistling ducks, egrets and many other birds. In this picture, I'm up on a mountain just behind the station overlooking the marsh.