The Latin American Program conducts and supports basic and applied research, especially as it relates to the ecology and conservation of wintering Neotropical migratory birds, and also strongly supports similar conservation-oriented research on resident bird species.

Current research in the Latin American Program focuses on the wintering ecology and conservation of Neotropical migratory birds, including population dynamics, ecological relationships, and habitat relationships at multiple scales, as well as understanding how birds respond to natural and anthropogenic change to their habitat.  Based on previous research efforts, we will continue to develop an understanding of population limitation of Neotropical migratory birds.  Priority species are those that breed in Western North America, and priority research sites are in West Mexico.  However, species which breed outside of Western North America, and research sites in the Yucatán, Central America, or the Caribbean, are supported when results can be generalized and can be made applicable to broader populations of wintering migrants.

Current Research Projects include:

Bird Use of Restored Riparian Habitat in the Overwintering Period

This project seeks to provide guidance for the restoration of riparian vegetation to improve and enhance wintering habitat vital to the long-term conservation of migratory birds.  We plan to relate bird use, overwinter site persistence, and survivorship to restoration design, silvicultural practices, water flow regimes, and other restoration activities.  Because in this study we are able to work simultaneously in well-conserved riparian plots and restoration plots, and because most of these sites have been previously assessed as breeding habitat by PRBO and partners, we are in a unique position to:

1. describe the wintering ecology of migrants in riparian habitat in both the temperate and tropical zones;
2. evaluate the value of riparian restoration efforts for migrants during the non-breeding period; and;
3. test whether restoration conditions favorable to breeding birds translates to conditions favorable to wintering birds.

This is an intensive effort that involves point counts, constant-effort mistnetting, resighting of color-marked birds, and vegetation sampling to determine local site fidelity, and to estimate survival rates of migratory (and resident) bird species at each site and in each habitat.  Point counts and constant effort mistnetting provide an index of annual productivity and information on annual survival.  Resighting of color-marked birds is used to determine site fidelity and overwinter site persistence or survival over the non-breeding season.  This will also provide badly needed data on life history traits and demography of species, and provide direct information on habitat conditions necessary for overwinter survival.  Together these data are required to assess the winter ecology of Neotropical migratory birds and habitat conditions for land and species management.  Study sites are located in the Sacramento River Valley (California), San Joaquin River Valley (California), Baja California, the Colorado River Delta (Sonora), Ayuquila River (Jalisco), and in Quintana Roo.

Conserving Riparian Habitats: West Mexico Riparian Assessment

The goal of assessing the value of riparian zones to overwintering Neotropical migratory birds in West Mexico is being addressed through PRBO’s collaboration with the Universidad de Guadalajara’s Centro Universitario de la Costa Sur (CUCSUR) and the Ayuquila River Riparian Monitoring Project.  This project seeks to evaluate and monitor habitat restoration efforts in the Lower Ayuquila River Watershed which had been severely damaged by contamination and agricultural activities.  To strengthen the ornithological component of a large, inter-municipal initiative for the integrated management of the watershed, M.C. Sarahy Contreras and Eduardo Santana (CUCSUR) established a collaboration with PRBO researchers Steven Latta and Borja Mila.  In 2003-2004, we established permanent monitoring sites in well-preserved and restored riparian habitat, operated the mist-netting stations over three months, and trained project personnel, some of whom are graduate students at the Universidad de Guadalajara.  Banding has focused on both permanent resident and winter resident migratory birds, as habitat conservation efforts need to be focused on multiple species still common enough to respond to changes in land acquisition, restoration and management efforts.  Measuring the response of multiple species to conservation efforts will help guide management and provide an effective evaluation of restoration actions.

Avian Communities and Resource Use in Northeastern Yucatan Peninsula

This research and monitoring project is currently the ONLY year-round avian project being carried out in the entire Yucatan Peninsula.  This project will: 1) provide vital information on stop-over and wintering Neotropical migratory birds, as well as resident birds (including endemics), with data such as these never before collected annually in the Northeastern region of the Peninsula; 2) provide a pilot project to study bird use of cenote resources and determine how these important landscape features may provide benefit both migratory and resident bird species, especially in the dry season; and 3) study the effects of disturbance on the avian community; disturbed habitats include successional forest (acaula) modified by fire, cattle pastures, and citrus plantations.

Demographics, Breeding Biology, and Conservation of Hispaniolan Birds

Here we seek to build upon previous work on birds of Hispaniola, and identified conservation priorities, to provide a comprehensive understanding of the demographic structure, habitat needs, and breeding biology of Hispaniolan endemic and resident bird species, measure productivity and survival among nesting birds, expand avian monitoring programs in the Sierra de Bahoruco, and provide a basis for sound management and conservation activities in the region.  Demographic data (sex ratios, age distributions, nesting success and survivorship) will be combined with habitat relationship data (vegetation characteristics) to determine factors or events that may be regulating populations.  It is only with this sort of intensive field study that the biologically important data can be gathered which is necessary for management and conservation decisions.

The Importance of Regenerating, Moist Broadleaf Forests to Birds in National Parks of the Dominican Republic

Here we seek to build upon our previous work, and identified conservation priorities, by studying demographic structure, habitat needs, and non-breeding biology of Hispaniolan endemic, permanent resident, and winter resident bird species in regenerating broadleaf forest.  Large portions of Hispaniola have been converted to agricultural use through slash-and-burn practices, and other forested sites are selectively cut and the understory burned to promote forage for cattle grazing.  The effects of these practices, and the use of these early- and mid-successional habitats by birds, has never been studied.  Whatsmore, for management planning efforts, there is a need to know how this most common form of habitat conversion effects bird demographics and survival, and how birds respond to regeneration of these habitats.  Our goals are to compile a comprehensive database of the demographics and non-breeding ecology of Hispaniolan endemic, permanent resident, and winter-resident bird species in regenerating broadleaf habitat, to measure site fidelity and survival among birds, and to provide a basis for sound management and conservation activities with respect to the Sierra de Bahoruco National Park.  Demographic data (e.g., sex ratios, age distributions, and survivorship) will be combined with habitat relationship data (vegetation characteristics) to determine factors or events that may be regulating populations in these habitats.