In 1900, the first Audubon Christmas Bird count (CBC) was conducted in 25 areas (count circles) with 27 observers in the United States and Canada.  Now, more than 100 years later, the Osa Peninsula Christmas Bird Count Circle is one of over 2200 Audubon Society count circles located in 20 countries in existence today.

This year marks our 10th Anniversary of the Osa Peninsula Count and the 6th annual Corcovado National Park CBC both held on December 21st 2019.

With our 10 YEAR ANNIVERSARY, we are coming full circle with our focus on the Yellow-billed Cotinga (Carpodectes antoniae) one our most endangered, endemic and lovely species on the Osa! As you may remember this was our focal bird species for our First Annual CBC back in 2010.  We unearthed our old shirts and memories and had a good laugh!  We are also highlighting a Theme this year entitled…

                “Stand Up and Be Counted: Birds, Indicators of Climate Change”

This theme speaks to the community participatory avian monitoring we have been conducting on the Osa for many years now and the Costa Rica Birding Route on the Osa through ICT (Instituto Costarricense de Turismo).   On this route and all of our CBC and monitoring routes, we contribute data to eBird and Audubon in the global effort to monitor birds over the long haul and help scientists understand climate change in the tropical landscape over time.

This year marks the 120th Christmas Bird Count (CBC).  The CBC is a one-day 24-hour event that occurs between December 14th and January 5th. These tens of thousands of volunteer citizen scientists head out, often before dawn, to count birds, and to be part of a long-running tradition in avian conservation and science.  Fortunately for us on the Osa, we don’t have to wear a big parka braving the cold down here!

Audubon has established an official methodology for all observers to follow which helps to standardize information. The CBC covers a circular area with a 15-mile diameter and anybody within that circle can be a part of the count. All birds seen or heard are recorded along a pre-defined route or area. That’s it! You can even count birds that come to your feeders if you like.  Of course, there is a bit more to it, but that covers the basics.  The data then goes into the Audubon Society database and Cornell’s eBird which is also available to the public.

The Osa CROP (Costa Rica Osa Peninsula) circle covers much of the area outside of Corcovado National Park circling around Luna Lodge, Osa Conservation properties, El Remanso, Bosque del Cabo, Lapa Rios, Cabo Matapalo, Puerto Jimenez, Playa Sandalo, Bosque del Rio Tigre and Dos Brazos.  You get the idea.  This area is extremely important because it includes the biological corridor from Matapalo to the park as well as a sizeable portion of urban landscape to the east where following bird population trends become necessary.


Corcovado National Park CRCO & Osa Peninsula CROP bird count circles

Corcovado National Park CRCO & Osa Peninsula CROP bird count circles

So how does the Christmas Bird Count help protect species and their habitats?

Data collected from volunteers is used by biologists and other interested parties to study the long term health and status of bird populations throughout the Americas and to see how populations have changed over time and space over the last 100 years. Scientists have used CBC data to detect birds in decline from fragmentation and/or loss of habitat and effects on populations from climate change as well.

Osa & Corcovado CBC Participants

Osa Birds: Research and Conservation, Bosque del Rio Tigre, Osa Conservation, Luna Lodge, SINAC-ACOSA, Lapa Rios, Bosque del Cabo Rainforest LodgeAve Azul de Osa, El Remanso, Everyday Adventures, Grupo Monitoreo Biologico Comunitario Rancho Quemado, Osa Outdoor Adventures, Surcos Tours, Osa Wild-ASCONA, Osa Birders Tours, Aventuras Tropicales Golfo Dulce, Fundacion Neotropica, Osa Safari Rainforest Adventures, ACODOBRARTI, Aves y Bosques de Osa, Punta Preciosa, Finca Exotica and Crocodile Bay Resort.

Past Reports Osa Peninsula Circle

Audubon Count Summary Report 2012

Audubon Count Summary Report/ Osa 2013

Audubon Count Summary Report/Corcovado 2013

Audubon Count Summary Report 2014

Audubon Count Summary Report 2015

Audubon Count Summary Report/Osa 2016

Audubon CountSummary Report/Osa 2017

Audubon Count Summary Report/Corcovado 2017

Audubon Count Summary Report Osa 2018

Audubon Count Summary Report Corcovado 2018


The Corcovado Circle count was cancelled for the year 2016 due to Hurricane Otto.

CBC-LogoOsa Birds is the official organizer and compiler of the Osa CBC.  We would like to thank all CBC participants who have made all these years a true success!

We report all bird observations for the peninsula to the Audubon Society database and eBird.

For more information, or if you’re interested in participating please contact karenleavelle/at/