A 2007 study by the Organization for Tropical Studies (OET) showed that around the biological research center of La Selva, in Sarapiqui, the frog populations have decreased some 75% in the last 38 years.  This has motivated the OET to launch a campaign for protection of these delicate jungle creatures, which the OET claims are biological indicators of the health of the earth’s ecosystems.  Why are the frogs dying?  Reasons cited for the dramatic decrease in the populations of La Selva include drought that results in less plant foliage and thus less of the leaves that provide space for the frogs to reproduce.  Another reason cited is the use of chemicals in agriculture.  Also cited as a factor is the increase in temperatures at night.  One of the prime factors especially in higher and colder altitudes like Sarapiqui is the proliferation of a mushroom that is deadly to the frog.  This is the same mushroom that is believed to be responsible for the earlier disappearance of the Sapo Dorado Holdridge (see previous blog post).  The OET will produce a calendar that features photos and information of the frogs that are most endangered to create greater awareness among the public that something needs to be done for their protection.  Proceeds from sales of the calendars will go to increase investigation into ways to prevent further diminishing of the frog populations in La Selva. The calendars are available in the office of the OET at the Universidad de Costa Rica.