This small Central American country boasts of an amazing 850 species that can be found within its national boundaries. Astoundingly, this figure is higher than the amount of birds that can be found in all of North America, from the southern border of the U.S. to the Arctic extremes of Canada and Alaska. Another way to look at this statistic is that it represents over 8% of the world's bird species.
Half of the country is mountainous or at least hilly, and this in combination with varying temperatures and levels of rainfall creates a plenitude of forest and vegetation types. These ecosystems, in turn, support the wealth of birds.
The story behind this diversity takes one back into the regions' geological history. About 65 million years ago the Pacific and Atlantic Oceans were connected in the region where Costa Rica stands today. Tectonic activity prompted the creation of volcanic islands that began to fill the gap that separated southern Nicaragua from northern Panama. These early islands were probably visited by members of bird families, such as cuckoos, parrots, pigeons, and waterfowl, renowned for their ability to colonize remote islands. Larger islands were believed to have been centers of evolution in their won right. What today are the mountains of the Cordillera de Talamanca and the Chiriqui highlands of Panama are home to many endemic genera, species, and subspecies, which lends validity to the idea that this mountainous area might have been just such an island.
In time the islands rose far enough out of the sea to form a land bridge (Approximately 3 million years ago). This began a cycle of migrations, both north and south, that enriched the avifauna of Costa Rica and Panama immensely. Neotropical families such as the antbirds, jacamars, puffbirds, hummingbirds, and the woodcreepers pushed north from South America, whilst thrushes, guails, jays, and gnatcatchers spread southwards. Subsequent glaciations might have facilitated the spread of highland species from both the north temperate and Andean regions. In the present day, the existence of an arid northwest, mangroves, paramo, and two long coastlines set the stage for even greater diversity.
Apart from sheer abundance, the neotropics also offer visitors from the temperate zone exposure to whole new taxonomic groups and phenomena particular to the area. Imagine for a moment, a horde of a million ants marching in search of prey. They can cover the forest floor like a rippling blanket, and fleeing before them are dozens of grasshoppers, spiders, cockroaches, and occasionally larger vertebrates such as lizards. These are the army ants. Certain members of the neotropical avifauna, such as the Bicolored Antbird, have evolved to forage exclusively in accompaniment of army ant swarms. These swarms will often attract up to a dozen different species, all drawn to the meal of flushed insects that have emerged from their hideouts, hoping to avoid the ants.
A second memorable experience might be your mixed flock. A hauntingly still forest can burst into life with a frenzy of birds whizzing by. Up to thirty species have been recorded in Costa Rican mixed flocks. Hawking and foraging in all levels of the habitat, the effect can be dizzying to the observer. Then, as quickly as it arrived, the flock can peter out and disappear into the deeper reaches of the forest. In truth, this manner of birdwatching can be the most fruitful in terms of species diversity.
Those with a bit of good fortune might happen upon a bird lek. Males of species such as the Bare Necked Umbrellabird and Long Tailed Manakin for leks, where two or more males gather to perform songs and dances to attract and mate with females. These displays can be simple or elaborate. In the case of the Manakin, it involves singing solos and duets, summersault dances, and a laborious butterfly fight just to have a female become interested.
Costa Rica is incredibly suited to birdwatching trips and expeditions. To begin with there is a well-developed system of parks and conservation areas, many of which are easily accessible. A rising awareness and a growing conservation ethic are helping to consolidate protection even further. Paralleling the park system is a network of hotels and accommodations that run the spectrum of price ranges. Travelers with even a modest budget allowance can still visit many a rich bird habitat.
Ecosystems and avifauna change considerably over rather short distances. As a result, a half day of travel or less can usually bring you to a completely different type of forest or habitat with a significant change in bird species. This translates into less travelling time and more time to simply savor the experience. It is not uncommon to witness between 300-400 species of birds during a two week visit.
It must be said that this small sliver of the world has much to offer in terms of natural history beyond the realm of birds alone. Anyone interested in botany, butterflies, reptiles, primates, and ecology as a whole will be well rewarded during a visit. In any case, for those who enjoy it all, or even for those who would rather spend their time looking exclusively for feathered friends, a trip to Costa Rica is an exploration of one of the most fascinating biomes of the planet.