Santa Rosa





The Area de Conservción Guanacaste is located in the Northeast of the Guanacaste Province and has an extension of 120,000 terrestrial ha and 75,000 marine ha, which comprise a gran diversity of ecosystems.

From Caribbean rain forest, with an annual precipitation of more than 3,000 mm; to the driest zones (900 mm) and oldest zones of Costa Rica (Santa Elena Peninsula), passing through cloud forest located in the lowest altitude of the country (top of Orosí and Cacao Volcanoes), regenerating dry forest, mangroves, and a large marine and coastal biodiversity. There are also historico-cultural traces that are relevant to national history (Museo Histórico Casona de Santa Rosa) and archeological sites, such as the Petroglyphs of Sitio Pedregal, by the Orosí Volcano.

Four biological stations and a reseach center have been established and located in different climate zones, with the object of promoting and facilitating the work of researchers, students, ecotourists, and organized groups, whether they be national or international.


A well marked dry season (november-may), high temperatures, intermittent rivers, deciduous forests and a high diversity of organisms, identify Tropical Dry Forest.

This forest used to extend throughout the Pacific Coast of Mesoamerica, but is found today much reduced in small patches in the region. Of the 80,000 ha of dry forest that are found in the ACG, one of the blocks in the greatest stage of regeneration is the Santa Rosa Sector.

The Tropical Dry Forest Research Center, created in 1992, with the object of creating better conditions for the development of the activities of researches and students, is located at this site.

The Research Center counts on five building, divided into dormitories for groups with a 64 person capacity, a hostel for resident researchers, a laboratory, a laundry room, and an administrative office where the conference room, the Documentation Center and the offices for the Research Program, Computer Support, and the Admistration of the Research Center and the Biological Stations, are located.

In the Santa Rosa Sector, near the Research Center, the Administration of the Area de Conservación Guanacaste, which also has the main offices of the Directorate, Accounting, Human Resources, Ecotourism, Biological Education and Sectors.

The facilities tied to the Research Center and which function as support for the different users of the Center are: a dining hall, electricity, drinking water, telephone, fax, and photocopier.

To get to the Center you have to travel 35 kms to the northeast of the city of Liberia on the Interamerican highway, or 24 kms south of the city of La Cruz on the same highay; until you get to the entrance of the Santa Rosa Sector (which used to be called Santa Rosa National Park), and from there you continue on a paved road for about 7 kms until you reach the Research Center.

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This upper elevation site, Sector Cacao at 800-1400 m elevation, is reached by driving 9 km east from Potrerillos on the Interamerican Highway (where it is crossed by the Rio Tempisquito) to the town of Quebrada Grande (called Garcia Flamenco on old maps). Potrerillos lies 25 km north of Liberia. Take the gravel road out of the north corner of Quebrada Grande (heading east toward the small town of Dos Ríos on the Caribbean side of the ACG). 1 km out of town take the first (only) dirt road north (left), which continues 3 km north to the tiny bridge over the Río Gongora, which is the southern boundary of the ACG. From here, the access is only by 4-wheel drive vehicles, and some portions of the road can be impassibly slippery for periods during the rainy season. Continue north on a primitive track across open (gradually regenerating) pastures, through several gates, to the road end at Los Naranjos (900 m, Rio San Josecito), where the unbroken forest begins up the southwest slope of Vólcan Cacao. From Los Naranjos, the broad trail winds through primary intermediate elevation rainforest (Los Arenales) for about 1 km to the Cacao Biological Station (CBS) at 1000 m elevation, on the uphill side of a 20 ha pasture cut out of the forest (and destined to remain pasture). Heavy objects are transported from Los Naranjos to the CBS by ACG horses that pasture at the CBS.

From the CBS a broad trail winds up through the primary forest to 1400 m at the Derrumbe site, and a narrower steep footpath winds up to the summit at 1550-1650 m. This very fragile and small habitat requires permission for use. This gradient from intermediate elevation seasonal evergreen forest to cloud forest on the summit of Volcan Cacao is extremely steep. Equally steep is the gradient from intermediate elevation forest to the dry forest on the lower western slopes of Volcan Cacao, directly west of the CBS and below the fire lookout house on the top of Cerro Pedregal (1000 m). The CBS provides excellent access to the kind of forest that grew many centuries ago on what are today's coffee fincas around Grecia, Alajuela and Heredia. A broad trail extends from the CBS down to the Maritza Biological Station.

The CBS dormitory, with 4 toilets and 2 showers, has beds for 32 people in four rooms (a small house with bathroom can accomodate a few more). The Sector Caretaker's house doubles as kitchen and dining hall for researchers and groups. The research laboratory is a moderate-sized building with tables and blackboard. The building complex can rustically accommodate a field biology course or moderate-sized group of ecotourists. With advance reservations, the ACG can provide meal services and bedding at the CBS for groups or individuals for moderate prices. There is no electricity, but there is ample running water. Heavy clouds and rain can dominate for many weeks during the rainy season, and winds can be strong. Nights can be as cool as 14-16 C°.

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This interface between the dry forest and Pacific slope rainforest at 500-600 m elevation, Sector Orosí, is reached by driving 14 km east on a dirt road from the intersection of the Interamerican Highway with the paved road to Cuajiniquil (9 km north of the entrance to sector Santa Rosa). This road is easily passable in dry weather with 4-wheel drive, but during rainy periods requires considerable skill to pass the mud-holes. After unusually heavy rains, three streams that cross the road may be impassable for several hours.

The Maritza Biological Station (MBS) lies on the western foothills of Vólcan Orosí (1450 m) (not to be confused with the Orosi area in the vicinity of Paraiso to the east of Cartago, Costa Rica, a site of much collecting activity around the turn of the century). 80 m south of the MBS flows the headwaters of the Río Tempisque (here called Río Tempisquito), which drains into the Pacific. 200 m north of the MBS flows the Río Sapoa (here called Quebrada Jorco), which empties into Lake Nicaragua and thence to the Atlantic.

The MBS has been developed jointly with the Strout Aquatic Research Laboratory of the Philadelphia Academy of Natural Sciences to serve as an aquatic biology research station. It also provides excellent access to the regenerating interface between lowland dry forest and the undisturbed evergreen but strongly seasonal forests extending upslope to the cloud forests on Volcan Orosí and Volcan Cacao. A well-defined trail extends across this transition up to the Cacao Biological Station at 1000 m elevation. The MBS receives 2000-4000 mm of rain during the May-December rainy season, and is often very windy.

The MBS dormitory houses 32 people in four large rooms, with showers and bathrooms, and 24-hour electricity (110 v). The large research laboratory and classroom, and adjacent multiuse building, can comfortably accommodate a field biology course or moderate-sized group of ecotourists. With advance reservations, the ACG can provide meal services and bedding at the MBS for groups or individuals for moderate prices. The Sector Caretaker's house doubles as kitchen and rustic dining hall. The MBS resident biologist house may also be able to accommodate a few long-time researchers.

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This Caribbean slope foothill rainforest site, Sector Pitilla (400-800 m), is reached by driving 35 km east to Santa Cecilia from the government checkpoint on the Interamerican highway about 4 km south of La Cruz (22 km north of the entrance to sector Santa Rosa). At Santa Cecilia, turn south on the (only) road to Upala, and at approximately 2 km, at the end of the orange plantation, turn west (right) on the first dirt road. This road enters the ACG after 3 km and after 4 km more, ends at the Pitilla Biological Station, which lies at the northeast corner of the ACG. It is passable with a 4-wheel drive vehicle, except after some rains, but when it is wet it requires a driver with substantial experience on small dirt roads.

The PBS (600 m elevation) lies at the interface of a several thousand ha of regenerating forest 1-80 years old, pastures, and 10,000 ha of primary rainforest to cloud forest that has been disturbed only by earlier light hunting and the occasional severe wind storm. Immediately to the west of the station, the volcanic foothills rise to the top of Cerro Orosilito (1100 m) and then drop down into the Rio Mena, to again rise steeply to the top of Volcan Orosí (1450 m). Sector Pitilla is one of the most species-rich sites in Costa Rica. Approximately 4 m of rain falls between May and February, and even the 2 month dry season remains moist. About 12 km of trails provide easy access to representative habitats, but the area is largely unexplored.

The two-room dormitory has 20 beds (expandable to about 30 by sleeping on floors) with 3 showers and toilets, adjacent to broad roofed porches and corridors for laboratory work and classroom activities. There is no electricity, but there is ample clean water for showers and drinking. The kitchen (gas stove, no refrigeration) can be used by individual researchers. With advance reservations, the ACG can provide meal services and bedding for groups or individuals for moderate prices. The PBS is occupied full-time by the Sector Caretakers and resident parataxonomists.

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Playa Nancite is reached by driving southwest from the ACG Administration Area for about 6 km down to the bottomlands behind Playa Naranjo, and turning northwest (right) at the fork, and driving about 4 km further. About 200 m before reaching the end of the road in the Estero Real camping area, a very obvious footpath extends north up over the rocky ridge and down into Playa Nancite (one hour strenuous hike). The dirt road from the Administration Area to this trailhead is only reliably passable by 4-wheel drive vehicle during the dry season, and during dry periods (sometimes late July and August) in some rainy seasons. Hikers to any areas in the Playa Naranjo - Playa Nancite region should take drinking water at all times of year.

This small beach is the site of the major nesting aggregation ("arribada") of Pacific Ridley's Turtles, and substantial research on them. The beach is backed by variously perturbed remnants of tropical dry forest on rocky slopes and flats, in various stages of regeneration.

This fragile site and its minimalist building (sleeping space for a few people, sometimes a gas generator for electricity, a small kitchen) require careful monitoring to avoid excessive impact by users. An access permit is required from the Research Program (office in the Santa Rosa Biological Station) when there is turtle or nestling activity (first moon quarter, July through November), at which time a maximum of 30 people are allowed to be in the area.

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