Results tagged “birds” from EcoMap Costa Rica

The student reports have now been published as PDF documents:

http://www.ecomapcostarica.com/reports/index.shtml

The main page now offers a link under the Reference section containing an annotated bibliography for the project.  The bibliography was compiled by the students in BIO 3416 as they researched background material on mapping techniques and the flora/fauna of Costa Rica.  It is important to have a broad overview of what this research will entail by looking at what others have conducted in the field.  We hope to add to this bibliography with even more detailed citations and additional references after we return from Costa Rica.

From left, Kat Miller, Katherine Biernat, and Adriane Smith.  Photo by Jim Varnum

Today we went to the Cedar Ridge Preserve with Dr. Brown in order to get first hand experience sighting and identifying bird species. We were even fortunate enough to see a Painted Bunting and Indigo Bunting as well as some other bird species. In class we wrote our finalized project protocol and equipment list. We met with the mapping group and determined that an x-y coordinate system would be used for our labeled observation points. We also decided what information we'd like them to record for each site. We also typed up our data sheets.

- The bird group

Today we discussed specific avian habitat types. We correlated island biography with fragmentation due to deforestation. Based on this relationship, the goal of the Meso American Forest Corridor is to reconnect the forest by creating larger islands and decreasing distance between islands. We talked about bird phylogeny and methods of identifying birds. AND we discussed how excited we are for 6am mornings!

- Katherine, Kat, and Adriane

Katherine, Kat, and Adriane are the members of the bird survey group. We are all biology seniors of the University of Dallas. Today, May 20, 2008, we had our first day of Field Ecology. We had our introductory overview of the course and detailed information about volcanology and Costa Rican geology. Specifics on Arenal. We were also assigned our groups and tonight we have plans to start our research. In Costa Rica we will be doing birds counts twice a day at 6am and 4pm. 

The Red-capped Manakin is a member of the family Pipridae, limited to areas of the lowland tropics.  Manakins have experienced a long history of sexual selection, resulting in a selection for brightly-colored males with elaborate courtship displays and females with less coloration.  They are generally lek-breeders, typified by central display areas called leks that are used by several males in order to attract a female.  The females visit the lek and observe these displays before settling on one particular male as a mate. The Red-capped Manakin display on the lek can be viewed in a well-known clip posted to YouTube.


Photo by Lynn Barber, Fort Worth Audubon Society

Birdwatchers looking for manakins find it difficult to see them in the dense understory layers of a forest.  However, the birds can be brought out more into the open by mimicking some of their sounds through clapping and finger-snapping.  The birds, curious about a potential rival nearby, will move into an open perch to investigate the sounds and allow for a closer look.

The tropics hold a variety of species that are unique, and none are more interesting and challenging than the antbirds. The antbirds are small passerines within the family Thamnophilidae, and are restricted to tropical Central and South America.  A second ant-dependent family, the Formicariidae, are found more commonly on the ground, and resemble thrushes in behavior and morphology. 

The antbirds are generally insectivores, and gained an association with ants due to their habit of some of following columns of army ants to feed opportunistically on the insects that are attempting to flee the ants' advance.  So while they do not necessarily eat ants (although some are obligate ant-followers), the swarms of ants enhance feeding opportunities.

Barred Antshrike (Thamnophilus doliatus) in Jaú, São Paulo state, Brazil.  Photo taken by Dario Sanches, from Sao Paulo, Brasil, September 30,2007

There are a number of species that belong to the Thamnophilidae, and these species are typically divided based on size and foraging behavior.  These species include the antshrikes, which are large and have a hooked bill similar to the shrikes found in other parts of the world.  Smaller antbirds include the antwrens and antvireos, that will forage for tinier insects and often forage on the wing.  All members of the group prefer being in the darker lower levels of the forest under a thick canopy.  They are commonly cryptic, with dusky brown, black, gray and white coloration.  However, some may have iridescent face and neck coloration, as in the case of the Oscellated Antbird.

At the Leaves and Lizards site many of the antbirds can be found in the mature tree habitat, but could be expected to increase in number as the forest becomes more dense and begins to become attractive to insects and army ant swarms.

The Keel-billed Toucan, Ramphastos sulfuratus, is one of the most distinct and charismatic species of the Costa Rican rainforest.  Readily identifiable by its bright green red and orange bill, this species is a common resident of the rainforest canopy.

Toucans are members of family Rhamphastidae in the order Piciformes, and have several qualities in common with another family of this order, the woodpeckers.  All members of this order have zygodactyl feet, with two toes pointing forward, and two toes behind.  This toe arrangement provides the greatest possible traction for hanging on to tree trunks.  Like woodpeckers, the toucans are hole-nesters, and due to limited numbers of natural holes and crevices will often be forced to share the holes with other toucans.

The diet of a toucan is mainly fruit, although they will sometimes consume eggs, insects and vertebrates (mostly frogs and lizards) to add protein to their diet.  At the study site we have found that the resident toucans will sometimes move from tree to tree monitoring the ripeness of fruits in order to get the fruits at their peak.  We hope that restoration of the Costa Rican rainforest helps to provide more space for these birds to live, and a better food source for them and their young.