The Ecosystems of Costa Rica

Ecosystems are really important in environmental conservation. An ecosystem must have all the right elements in the right amounts to keep its natural balance. Too much of one thing, too little of another, too many invading pieces, and all the other parts of the equation suffer. Protecting an ecosystem means protecting all the elements—big and small, organic or inorganic—that compose it. This guarantees a cleaner world with healthier animals, plants, and everything in between.

This includes us, humans. It’s easy to separate ourselves from the wild world—no other species has TV or WiFi, after all—but we’re part of all the ecosystems of the planet. We are everywhere! As part of the ecosystem, we can as easily disrupt it as encourage it to thrive. By taking care of the ecosystems around us, we take care of ourselves. Nature is essential to our survival, and we have all the tools to help it survive too.

The marine shelf refers to the underwater ground that extends from the shoreline to the deep sea floors. Everything in this space depends on the life that grows on the marine shelf, called benthic productivity. Sunlight and nutrients are abundant in these areas but vary depending on how deep into the ocean you are, so these are the key elements determining how many species live where. Nutrients come both from the deep ocean—through upwelling currents—as well as from the mainland—mostly through rivers. There are a total of ten ecosystems in marine shelf biomes. Costa Rica has seven of them, the most famous being the coral reef.

Photic refers to the light these coral reefs receive regularly. This ecosystem is very delicate, occurring only in specific conditions. The waters where they grow have to be: tropical or subtropical, shallow, open, coastal, and with a salinity between 3% and 3.8%. Although various corals can withstand a variety of temperatures (between 62-93 °F), they can’t survive in waters a bit cooler or warmer than that. Coral reefs grow slowly but provide an important habitat for a highly diverse range of animals and other organisms, like algae.

Seasonal storms and heat waves are important for corals because when they damage the reefs, the corals have an opportunity to grow back again stronger. However, if these patterns are affected by climate change (too many storms and too much heat) or human intervention, the normal patterns are broken and coral reefs don’t have a chance to regrow. Because of this, coral reefs are one of the most endangered ecosystems in Costa Rica, as well as one of the most beautiful. In fact, coral reefs in the Caribbean are great diving and snorkeling spots because of the stunning vistas and the amount of animals they have. If you want to see them, it’s important to take care of them!

This biome is the largest on the planet because it encompasses all open ocean waters. Because light and nutrients vary depending on how deep underwater you are, diversity is highest near the surface. Those lifeforms in the deepest parts are extremely adapted to the lack of sunlight and high pressure from the water. Animal migration is very common in this biome, with sea creatures moving upwards and downwards and from one area of the planet to another. Costa Rica sees a lot of these migrations, with yearly natural events such as whale mating seasons, turtle nesting, and relocation of sportfishing species.

One of the most active ecosystems in this biome is called the Epipelagic Ocean Waters. These are the top layers that receive the most sunlight. Because of this, these ecosystems see the most photosynthesis too. In fact, these are the waters where half of all global carbon fixation occurs! Carbon fixation is the process where organisms turn exterior carbon into internal nutrients. Because there are so many plants and small organisms, there are also plenty of marine wildlife and lots of activity going on. This is where most valued sportfishing target species also live, such as marlin, sailfish, and roosterfish.

As a tropical country, Costa Rica is a great destination for these species. You can find them year-round, but due to migration patterns for reproduction or feeding, they reach peaks at certain times of the year. Costa Rica’s sportfishing tournaments work around these peaks.

The deep sea floors include more or less the waters below 820 ft deep, where sunlight doesn’t reach that well. This is not as far away as it looks at first. Deep sea floors can cover everything from where the low tide ends to the deepest parts of the ocean, almost in the Mariana Trench. This biome doesn’t have a lot of biodiversity, and the animals and plants here are well-adapted to the pressure and scarce light. This biome usually depends a lot on what falls down from the Pelagic Biome to survive. Truly all parts of nature are connected!

This is a very special category of biome. The Greek root “anthropo-” means “human,” so this biome refers to the artificial structures dumped into the ocean that have now become the home of marine life. This includes accidental shipwrecks, infrastructure such as pipelines, and mechanisms purposefully put in the water for economic or ecological reasons. In some locations where corals have died out, these structures become a stand-in environment for fish and algae to live in. Divers also often frequent these because of the variety of sightings they provide, and many scientists use them to help the environment thrive. FADs are another example (Fish Aggregating Devices, also known as seamounts). They are placed in strategic locations of the deep sea to become the home of small fish or mollusks. In turn, they attract bigger species for sportfishing purposes.

This very unique biome is distributed along the coastlines of the world. It presents a huge variety of plants and animals based on the way freshwater, the ocean, and the land affect each other. From strong delta rivers to saltmarshes, this biome usually depends on the nutrients coming from both rivers and ocean tides. The most important role of this biome is regulating the salinity levels that travel from the sea to the land (most saltwater gets stuck here and doesn’t affect the soils beyond). It also acts as a barrier between storms and the mainland. Costa Rica has two of the three main ecosystems in this biome.

Mangroves are located in tropical and warm regions around the world. This group is characterized by having highly specialized lifeforms, especially when it comes to flora. It has both aquatic and terrestrial species, all interconnected and dependent on each other. Mangroves act as nurseries for many types of creatures. For example, in the water you often find shellfish, frogs, fish, and shrimp. Up in the tree canopy, you find many birds, reptiles, and small mammals like monkeys. These ecosystems are also called carbon sinks, meaning they gather a lot of organic matter in their sediments, creating a very rich soil. Mangroves are great areas to explore because of all the sights they provide, so often travelers go on kayaking tours across their waters.

A river delta is the section of the river that crashes into the ocean. This means the waters here are a combination of fresh and salty hardly found anywhere else. River deltas have many shapes and levels of salinity depending on the size of the river, the materials it drags from the inland, and how the ocean waves affect the river. These are very complex feeding webs, where everything from plankton to terrestrial predators interact. Costa Rica’s largest river delta is near the Osa Peninsula and is called the Diquís Delta. Here, two rivers, the Térraba and the Sierpe, join to form important wetlands right at the edge of the ocean.

As a tropical country, Costa Rica is most associated with these biomes. They are characterized by high levels of productivity. This means there are many species sharing and competing for space and resources in the same area. Even though biodiversity is high here, it depends on rain (affected by seasons and altitudes) and soil nutrients. Did you know that these biomes are dominated from the bottom up? This means the species that live on the ground dictate the lifestyle of everything else. And the dominant species might be unexpected: trees. Tropical trees are often very tall and firmly rooted to the ground, and they engineer the habitats of all other organisms.

These are some of Costa Rica’s most famous ecosystems. The structure of these forests is complex and characterized by very tall trees. This makes rainforests vertically layered, a very curious structure. From top to bottom, you can see different types of flora and fauna adapted to specific roles depending on which level of the forest they live in. For example, the smaller plants on the ground levels don’t need much light because the trees shade them. Some animals could even spend all their lives in the canopy of the trees, where their food grows, and go nowhere else.

These ecosystems usually have fast-growing plants and abundant leaf litter. All this organic residue accumulates in the ground, keeping the soil moist and high in nutrients as it decomposes. There are many relationships between the species of these forests. Invertebrates are plenty, feeding mammals and birds. In turn, they pollinate the forest by dropping fruits and seeds. The conditions of these ecosystems are pretty stable throughout the year, too. The farther away you get from the equator, the subtropical forests may see some mild seasonal changes. Some of Costa Rica’s most famous rainforests are in Arenal and Manuel Antonio. They’re famous for good reason!

These forests are famous for very marked dry seasons interspersed with big periods of growth when the rain comes. The diversity of species is high, if different from those in the rainforests. Fungi and microbes are particularly important for this ecosystem. During the driest months, organic litter (like leaves and branches) accumulates on the ground. When the rainy months come, the fungi and microbes flourish and decompose it, creating a fresh layer of nutrients to keep the forest going during the next dry season.

These patterns make the foodwebs in these forests very complex. Seasonal migrations from larger animals are very common, too. Many confuse Costa Rica’s dry forests in Guanacaste as the least biodiverse of the country, especially compared to rainforests. But it’s a rich ecosystem, with a particular rhythm and species of its own. Just make sure to pay attention to the details and you’ll see how interesting it becomes.

Cloud forests are some of the most unique ecosystems in the world, occurring only under very specific conditions. An important characteristic is that they have a single-layered tree canopy. This means trees are roughly the same height when mature and that other plants like grasses are rare or absent from the ground below. If cloud forests occur very high in the mountains, dwarf trees become more common, too.

Humidity is abundant throughout the year. In addition to rainfall, the continuous presence of clouds keeps the forest moist all the time. Because of the cool temperatures year-round, species have to be sturdier to flourish here. However, cloud forests are havens of biodiversity, often presenting endemic species that are super-adapted to one specific place and show up nowhere else in the world. In Costa Rica, the Monteverde cloud forests are a paradise for nature lovers, especially birdwatchers.

Even though it looks like it’s taken out of science fiction, the term “cryogenic” simply means that something has or is at extremely low temperatures. So this biome refers to the parts of the world that we usually think don’t have much life. This includes the Arctic and Antarctic regions and the higher parts of mountains. Even though little grows here, there is highly specialized biodiversity in these places.

Regional temperatures often shape the ecosystems within this biome. Growth usually occurs seasonally when the weather is less extreme because these areas are frequently very dry and windy. The cooler climate slows down decomposition, so peat bogs are common in those places with more plants.

Paramos are a very special type of ecosystem within the Alpine Biome. They are limited to a few areas of Africa, the Americas, and Southeast Asia. Even as a tropical country, Costa Rica’s highest peaks have paramos! This is mostly around Chirripó Mountain, in the Talamanca Mountain Range. Plants here tend to be small, with shrubs, lichens, mosses, and grasses dominating the landscape.

Small mammals, various invertebrates and reptiles, and particularly birds, are the most frequent fauna of these areas. Larger animals like tapirs or jaguars make occasional appearances from time to time, though. The soils tend to be rocky and not very apt for agriculture. There are also large temperature shifts between night and day. Because of these characteristics, paramos are not very populated. All of Costa Rica’s paramos are strictly protected within national parks or nature reserves, because of how special they are. These are some of the most unique sights in the country, however, not many see them because most visitors stick to the warm beaches and the lush rainforests.

“Palustrine” is the scientific way to say that something looks marshy. The wetland biome is made up of all those places where land is steadily covered by water at least some time of the year. This is why there are many variations of this combination. Light is also abundant at least seasonally, but the most important indicator of biodiversity is water, determining how much life lives in the wetland. Another element that affects all wetlands is saturation. Too much saturation of the soil decreases oxygen levels in the ground to the point where decomposition can’t happen normally. That’s when you get peat!

Costa Rica has many examples of this biome:

All these are individual ecosystem functional groups within the biome, but they are similar enough it’s easy to analyze them together. Marshes can be covered in water either permanently or seasonally during the year. Both swamps and marshes occur in tropical and warmer areas of the world, and they usually present a lot of species of flora and fauna. Bogs and fens are their equivalent in the cooler climates, either high in the mountains or closer to the cold of the polar areas. They are all mostly treeless, with a few exceptions, and are dominated by grass, moss, shrubs, and other aquatic plants. It’s important to highlight that peat bogs are landscape sponges: they retain so much sediment they account for 40% of the world’s soil carbon.

Costa Rica’s wetlands present big levels of activity. Many animals, ranging from fish and frogs to migratory and resident birds, along with a large variety of plants (algae, grass, even trees) are specialized to live in these areas. Wetlands are important feeding grounds that maintain the local species in harmony. They also act as nurseries, with many animals rearing their young in the wetland to guarantee protection and nutrients. Palo Verde National Park and Caño Negro Wildlife Refuge are some of the most popular and important wetlands ecosystems in the country.

• La Nación’s “Día del Ambiente: Un paseo por 8 ecosistemas de Costa Rica.”
• Costa Rican Ecosystems (2016). Edited by Maarten Kappelle.
• Earth Observatory’s “Tropical Deforestation.”
• Smithsonian Museum’s “Mangroves.”
• Geographical’s “Geo Explainer: Cloud Forests.”
• Costa Rica’s National System of Areas of Conservation(SINAC).

• Wildlife in Costa Rica
• Guide to Top Birdwatching Lodges
• Eco-Communities in Costa Rica: The Complete Guide
• Tree Houses in Costa Rica