Friends of the Osa Science Plan

SUMMARY

Friends of the Osa is committed to preserving the biodiversity of the Osa Peninsula. The area where we work lies near Corcovado, a pristine national park, and contains a dynamic mosaic of varied land-use amidst mountainous primary and secondary forests, swamps and streams. These watersheds join with a diverse coastal zone which includes areas of high conservation importance, including lagoons, vast areas of mangrove and the Golfo Dulce, a unique tropical fjord.

We aim to increase understanding and preservation of the Osa’s interconnected terrestrial, freshwater and marine systems. We implement science-based conservation by addressing critical applied research questions across a broad range of themes and ecosystems. Our strategy focuses on protecting habitats and maximizing landscape connectivity outside of the protected park system. Our research goals can be broadly categorized under: species inventory and distribution; monitoring; landscape ecology and requirements of priority species; and ecosystem services and functioning. To complement the research outlined in this science plan, we achieve these goals through cooperation, training and education programs with local stakeholders and communities, organizations, universities, researchers, field assistants, students, ecotourism guides, teachers, school children, and others involved in the Osa.

PRIORITY PROJECTS

Within the framework of our four general research themes (described below), we are especially interested in supporting the following priority projects in the coming year:

• Databasing and GIS-based mapping of the Osa Peninsula region to identify habitat types, land-use categories, property boundaries, watersheds, demographic data, etc.
• Spatial biology of large mammals, especially jaguars, pumas, ocelots, peccaries, and tapir. Area and habitat requirements, and monitoring of their activity outside of the park, including the role of habitat corridors in facilitating movement
• Dynamics of keystone predators and prey, and their ecosystem consequences. In particular, how do jaguars and pumas affect coati populations, and in turn, how does coati population size affect sea turtle nest predation? Comparisons between hunted and unhunted forests and long-term camera trap monitoring
• Long-term monitoring and conservation of sea turtle nesting sites
• Distribution, habitat requirements, and ecology of endemic bird species, especially the black-cheeked ant tanager, mangrove hummingbird, and yellow-billed cotinga
• Telemetry of scarlet macaws to determine movement patterns, ecology, and conservation needs
• The role of lagoons and mangrove habitats as nurseries for fish, crustaceans and mollusks, including assessments of threats to these habitats (e.g. sedimentation, pollution, deforestation, commercial fishing)
• Monitoring fish populations working with sport fishermen to measure and tag their daily catches
• Potential environmental and social impacts of the proposed tuna aquaculture project in Golfo Dulce
• Mapping of natural resource use by local communities (e.g. monitoring the dynamics of artisanal fishing around Golfo Dulce, identifying threats to clean drinking water sources, etc.)
• Native tree reforestation programs, especially in riparian zones along streams and rivers, and their potential impacts on watershed health; stream monitoring
• Environmental and economical cost-benefit analyses of various types of land-use to establish recommendations and  sustainable alternatives for local communities (e.g. comparisons of cattle-ranching, pineapple, oil palm, teak, Gmelina, bamboo)

GENERAL FRAMEWORK:

RESEARCH THEMES AND PRIORITIES

1. Species inventory and distribution

Priorities given to:

• Taxa that are diverse, poorly known, and/or ecologically important in the ecosystem
• Measurement of population size or relative abundance in addition to species richness and composition
• Mapping of distribution and abundance (GIS-based)
• Well-designed and standardized sampling methods
• Comparison of community structure between baseline habitat/sites and one or more types of disturbed habitat/sites. Includes sites experiencing ongoing disturbance as well as those in various stages of recovery
• Comparison of community structure across habitat types
• Habitats that are poorly studied and may be especially ecologically important and/or vulnerable
• Effects of landscape structure and configuration on species’ distributions
• Assessment of species traits associated with their response to disturbance
• Measurement of appropriate environmental variables in relation to focal taxon
• Description of new species

In addition to the importance of knowing what and where species are in the Osa, inventories provide the foundation for many other kinds of studies, including monitoring, comparative and ecological studies. Without the resources to inventory all taxa, we focus on certain groups, including those which are less well studied or which may be especially important components of the ecosystem. We encourage abundance measurements and estimates of population size for several reasons. Measuring abundance as well as species composition can help identify rare or endangered species that may be especially vulnerable. Abundances measured with standardized sampling methods also provide a baseline for future studies that can monitor long-term population dynamics in relation to past or future environmental changes.

We particularly promote inventories that compare patterns of species richness, species composition and abundance across habitat types and disturbance regimes, as well as across local, regional and even global scales. Comparisons between habitat types are important for understanding how conservation of habitat diversity can maximize biodiversity protection. Understanding how species respond to various kinds of land-use and other types of human activities, as well as how habitats and species recover following these disturbances, is also a conservation priority. Some priority habitats, such as mangroves and riparian zones, may be less well studied and/or more vulnerable to human activities, and also contain many unique and important species. Focusing only on individual habitat or disturbance types provides an incomplete explanation for observed species distributions – it is also necessary to understand how the structure and configuration of various habitats across the landscape affect species persistence. In addition to measuring community structure, studies identifying which kinds of species are sensitive or resilient to environmental changes can strengthen generalizations and also suggest potential causes of species declines. Measurements of environmental variables that may affect the focal taxon can also strengthen the interpretation of observed patterns. Although a lower conservation priority, we encourage description of new species in conjunction with studies addressing some of the other priorities described here.

2. Species monitoring

Priorities given to:

• Endemic, rare and/or endangered species
• Species that play important ecological roles, especially keystone species
• Species of particular conservation benefit to people, either by providing ecosystem services or for other values
• Habitats that are poorly studied and may be especially ecologically important and/or vulnerable
• Long-term monitoring
• Response of previously intact populations following initial or ongoing disturbance
• Recovery of impoverished or extirpated populations following the cessation of disturbance
• Quantitative assessment of the consequences of changes in populations being monitored for the ecosystem and/or people
• Monitoring of appropriate habitat and environmental variables in addition to focal species

Monitoring of the dynamics of populations over time, often a temporal extension of species inventories, provides information that is even more useful for conservation. Monitoring data can be used to tease apart the influence of many different environmental variables on species’ population size and persistence. It also describes the trajectory of population increase or decrease which can be used to identify which species need protection or to evaluate conservation success. Many of the priorities for species inventories apply to monitoring for the same reasons. As described before, we cannot focus on all species or habitats. In addition to endemic and over-exploited or endangered species, we focus on species that are especially ecologically important or that are charismatic or important for people. Such species may provide ecosystem services or may have intrinsic or other value for local people, or may benefit the region by boosting ecotourism. We aim to monitor changes in populations associated with ongoing disturbances, such as various kinds of land-use, hunting and fishing, as well as the subsequent recovery of habitats and populations. We especially encourage studies that measure the consequences of population dynamics being studied. For example, selective hunting of large cats such as jaguars appears to have led to hyper-abundance of coatis, a popular prey. Uncontrolled by predators, coati populations can become so large that coatis eat the majority of sea turtle eggs laid on the beach.

3. Landscape ecology and requirements of priority species

Priorities given to:

• Endemic, rare and/or endangered species
• Species that play important ecological roles, especially keystone species
• Species of particular conservation benefit to people, either by providing ecosystem services or for other values
• Species with large area requirements
• Identification of threats and causes of species declines or local extinctions
• Identification of species’ habitat preferences and resource requirements
• Effects of landscape configuration on movement of individuals across the modified landscape (including habitat type, size, shape and proximity to other habitats)
• Landscape connectivity and design of appropriate habitat corridors for target species
• Spatial scale and patterns of individual movement

Certain species merit higher conservation priority than others for several reasons described above, and basic information about the ecology of these species is important for their protection. Identifying the specific threats and potential causes of decline for these target species is perhaps the most important task for designing and implementing a conservation strategy. Part of this knowledge comes from an understanding of which types of habitats these species require or are able to use, as well as their potential resource limitations. Predators and other factors may also play important roles. Since much of the area where we work consists of a mosaic of habitats, it is important to understand how individuals move across the landscape, as well as how much area they require.

4. Ecosystem services and functioning

Priorities given to:

• Habitats or species that provide ecosystem services to people
• Habitats that support higher biodiversity in adjacent habitats
• Ecological processes with wide-reaching ecosystem effects, such as predation, herbivory, decomposition, pollination, and seed dispersal
• Quantitative evaluation of the benefits/impacts of ecosystem services and functioning

Biodiversity provides several important ecosystem services for people. For example, mangroves act as a nursery for many of the fish species which are consumed by people, and riparian corridors along streams help protect water quality. Many species provide direct services in the way of food, building materials, and medicines, or for their cultural value. Others may act indirectly, for example by pollinating crops. Interactions between adjacent habitats, such as along the coastal zone, are an important mechanism promoting high biodiversity in the region. We also focus on species which are important for maintaining ecosystem integrity due to their ecological interactions. Changes in the populations of these functionally important species can have negative cascading effects throughout the ecosystem by altering trophic dynamics and processes such as seed dispersal. These types of studies are most effective if they quantitatively measure the ecosystem service or function of interest.

For more information or to inquire about working with Friends of the Osa on a scientific investigation, please contact Trond@osaconservation.org