Sea Turtle Conservation and Education Program

The Osa peninsula is located in the southern Pacific province of Puntarenas, Costa Rica (longitude 8°N, latitude 83°W). It contains a variety of different tropical habitats from coastal wetlands and humid forests to high elevation rainforest and farmland. The Osa contains the famous Corcovado National Park, the largest Park in the country, which National Geographic Magazine called “one of the most biodiverse places on earth.” Since 1991, the community and agencies that work in the Osa have cooperated in efforts to protect many of the natural resources of the peninsula and surrounding areas.

The flora and fauna of the Osa peninsula are very similar to that of South America and it is still the largest tract of intact rainforest north of the Amazon. The average rainfall in the Osa ranges from 2,500-6,000 millimeters per year, with a short dry season from January to March. The average temperature is 25 ºC with small local variation from altitude and other geographic features, and a relative humidity of 90%. The Osa is crisscrossed with freshwater from natural springs to raging rivers. This plethora of water supports the local communities and agricultural areas. The peninsula is surrounded by the magnificent Pacific Ocean on the west coast and the beautiful Gulfo Dulce in the east.

The Osa peninsula is teeming with life. From the largest scarlet macaw populations in Costa Rica to the incredible number of sea turtles that nest upon its shores, the Osa peninsula is an important biozone. There are 375 bird species, 124 mammal species (including 58 types of bats), 71 reptile species including the four species of marine turtle (Olive Ridley, Black Turtle, Leatherback, and Hawksbill), 46 amphibian species and 61 freshwater fish species. Many of the species that make their homes on the Osa are endemic, meaning this is the only place they live in the natural world.

The Corcovado National Park protects the ultimate remnant of tropical rainforest in Pacific Central America. There are still areas of the Osa where you can encounter animal populations that are viable yet threatened, like the large cat species: jaguars, mountain lions, ocelots, jagurundis, and margays. These cats need a lot of space for their individual territories. Animals like the Baird’s tapir and the squirrel monkeys are threatened but have been helped with conservation efforts. Other animals like the harpy eagle and giant anteater have almost disappeared from this area. It is very important that we establish and protect biological corridors in the Osa in order to maintain the viability of the populations of threatened species, before their ecosystem is fragmented and they disappear.

There are many species that are commonly seen in the Osa; four species of monkey (howler, white-faced capuchin, spider and squirrel), coatis, crab-eating raccoons, agoutis, three-toed sloths, iguanas, boa constrictors, blue morpho butterflies, keel-billed toucans, tamandua anteaters, ghost crabs, marine toads, white-collared peccaries, and many more.

There are more than 17 areas that have been declared a sanctioned Park, Wildlife Refuge, Forest Reserve or Wetland, including Rio Oro and Pejeperro Lagoon Wildlife Refuges and Pejeperrito Lagoon Wetland. They make up 145,425 hectares of which 42,469 hectares are Corcovado National Park.

Puerto Jiménez is the hub of activity for the Osa peninsula. Approximately 6,200 people live in Jimenez: 53%men, 47% women. Only 26% of the population lives in the Puerto Jimenez center where most of the commercial zone (shops, restaurants, internet cafes, super markets) is located. Puerto Jimenez is on the west coast of the Gulfo Dulce and is a major Costa Rican sport-fishing destination. By road, it is halfway between the Pan-American Highway and Corcovado National Park and therefore receives many tourists on their way to explore the jungle. There are many local cabinas and hotels in and around Puerto Jimenez as well as a domestic airstrip and bus station.

Wetlands are ecological associations where many species share flooded habitat and have adapted multiple strategies that allow them to flourish.

These species evolved to differing conditions: low oxygen, high or low salt concentration, abundance of water, high nutrient levels, etc.

The wetland ecosystems include a wide range of inland, coastal and marine habitats that share certain characteristics. Some of the different types include; lagoons, lakes, flood plains, swamps, etc.

The types of wetlands are broken down into three groups: saltwater, freshwater and artificial wetland

2. Freshwater
Riverine: Rivers and streams that are permanently flowing and have a great diversity life including water birds and crustations.
Inland Lakes and Lagoons: stationary wetlands that are closed to water outflow.
Swampland: permanent wetlands that are sobre suelos inorgánicos.

3. Artificial wetlands
These are created by people for many different reasons. In Costa Rica some of these are; aquaculture (tilapia, shrimp, etc.), drainage canals, hydroelectric systems, and irrigation for farming and gardens.

The area comprising Pejeperro and Pejeperrito Lagoons, is 22km long and 2km wide. Both of the lagoons and the area between are protected areas: Pejeperrito Wetland and the Rio Oro and Pejeperro Wildlife Refuges. Even so, these areas lack physical protection by the state and now the natural balance of this ecosystem is being threatened. Unsustainable fishing practices and the artificial opening of Pejeperrito in the dry season are completely opposite of the natural cycle of these wetlands.

These actions lead to the degradation of animal populations that are adapted to these environments, like fish and crustaceans. These are beautiful, wild and natural places that are being threatened by human development. We hope to help change the use of these incredible natural resources to a sustainable way.

This incredibly huge lagoon used to be completely surrounded by mangrove forest but has been altered and is now drainage area for many farms. The ecosystem shares many similarities with Pejeperrito but is not the same as Pejeperro does not usually close but is constantly flowing into the ocean.

The ecological value that these wetlands represent is priceless to the Osa Peninsula and its future conservation. For this reason SITMAR plans on integrating its programs to include the protection of these wetlands and guarantee their presence for our and future generations to enjoy.

Pejeperrito is a coastal brackish water lagoon located right next to Field Station Laguna Tortuga (hence the name). It is periodically open and flowing to the ocean and on the high tides of the year is inundated with saltwater; on occasion even sea turtles enter the lagoon. During the wet season, April-December, the lagoon fills up until it can hold no more water and bursts open with such force that many of the animals living in the lagoon are sucked out to the ocean. When this happens many marine predators come into the mouth of the lagoon to feed. The average salinity is 20ppm and is the only brackish water lagoon on the pacific coast of Costa Rica.

This lagoon is an important area to conserve because of its unique ecosystem. It is an ideal place to study the flora and fauna associated with this type of habitat. The most extensive population of wetland grasses, Phragmites communis, in the country lives here, the only other populations of this size that exist are in subtropical and cold regions. There are incredible populations of crocodiles, water birds, saltwater and freshwater fish and crustaceans, etc. not to mention the insects.