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Distribution & Abundance Maps for 1999

1999 Puerto Rican Breeding Bird Survey
Results and Summary

The Puerto Rican Breeding Bird Survey (PRBBS) was begun in 1997 to monitor the longterm status and trends of Puerto Rican bird populations.  The PRBBS consists of 44 8-kilometer (5-mile) roadside routes randomly located across the island.  Stops are located at 0.8-kilometer (0.5-mile) intervals for a total of 11 stops per route.  At each stop a skilled observer conducts a 5-minute point count recording every bird heard or seen within a 0.4km (0.25mile) radius.  Each route is begun at local sunrise and takes approximately 2 hours to complete.  Routes are run once per year between 15 April and 15 May.  The PRBBS is coordinated by the USGS Patuxent Wildlife Research Center.

Seven of 44 possible routes were sampled in 1999 and the data submitted to the USGS office, a marked decline in route coverage from 1998 when 19 routes were sampled.  Two routes were in the wet life zone, four routes were in the moist life zone, and one route was in the dry life zone.  A total of 1561 individuals was counted, representing 45 species (Table 1: opens in a new window).  Among the 45 species were 10 island endemics (Puerto Rican LizardCuckoo, Puerto Rican ScreechOwl, Green Mango, Puerto Rican Emerald, Puerto Rican Tody, Puerto Rican Woodpecker, Puerto Rican Flycatcher, Puerto Rican Vireo, Puerto Rican Stripeheaded Tanager, and the Puerto Rican Bullfinch, as well as, two endangered Puerto Rican subspecies: the Redtailed Hawk and Plain Pigeon.  Due to the paucity of data from 1999, we have refrained from further summarization and comparisons with previous years data. 

We are currently analyzing the data from the first three years of the survey in order to evaluate the future direction of the PRBBS and will make the results known when they are available.  And although it is too early to draw any definitive conclusions, it is clear that more routes must be sampled in future years than in 1999 if the data are going to be of value.

Acknowledgments
We would like to thank the PRBBS participants for the generous donation of their time and expertise.  We are especially indebted to the island coordinators for finding qualified observers to conduct the surveys.

Jose Colon
Rafael Cruz
Julio de Jesus
Alan Hedin
Enrique Hernandez
Mark Oberle
Jaime Otero
Jose Salguero-Faria
Jorge Saliva

U.S. Department of the Interior | U.S. Geological Survey
Patuxent Wildlife Research Center Laurel, MD, USA 20708-4038
http://www.pwrc.usgs.gov/bbs
Operations Contact: Keith Pardieck, email: Keith_Pardieck@usgs.gov
Analyses Contact: John Sauer, email: John_Sauer@usgs.gov
Last Modified: 10/31/01
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