Report from Panamá

Roberto Ibañez
Panamá
August 1999

In February 1998 Cesar Jaramillo and Roberto Ibañez visited the Reserva Forestal on the western highlands of Panamá, a site where a massive die-off of amphibians was witnessed by Karen Lips in December 1996-97. She noticed a drastic reduction in frog abundance in the area, especially along Quebrada Arena. Frogs have not recovered at this site (August 1999.)

Ulrich Hofer studied the species composition and abundance of the herpetofauna along an altitudinal gradient in the Bosque Protector Palo Seco, a protected area. This is on the Atlantic slopes to the north and adjacent to the Reserva Forestal Fortuna, in April-June 1998. He noticed relatively few frogs along his transect. There, the frogs most affected were those associated with streams. The cause of this mortality has been related to the pathogenic fungus, Batrachochytrium dendrobatidis. The margins of Arena stream, in Fortuna, where many Colostethus used to call, now remain near silent. Dendrobates speciosus, which was abundant in the area, now appears less common, but this species is not associated with streams. I cannot corroborate this due to a lack of data, nor point out a cause, though some may say that it is due to over-collecting in the recent past.

Last June-August, Karen Lips visited several sites in the highlands of Panamá and the Costa Rican border. She is doing a census of amphibia in sites where massive die-offs occurred, as well as sites where these might be expected to happen in the future. She is also collecting tissue samples from amphibia for microbiological analysis and D. Earl Green, of the US National Institute of Health, is collaborating in this part of the study.

In the lowlands of Central Panamá, frog populations seem healthy. The abundance and diversity of frogs fluctuates, but a generalised declining trend has not been noticed. The Proyecto de Monitoreo de la Cuenceca del Canal de Panamá (USAID-STRI-ANAM) is using three sites within the Canal watershed where frog monitoring was carried out in 1991-95. This project includes nine amphibian study sites as part of a long-term program of monitoring vertebrate populations in the region.