Nicaragua’s largest lake has several names: the indigenous tribes called it Cocibolca, the Spanish conquerors named it La Mar Dulce (the Sweet Sea), the people from Granada call it Lake Granada and it is nowadays generally known as Lake Nicaragua. The lake has a surface of 8,264 km², and it is located in the central southern part of the country. The oval-shaped lake is relatively uncontaminated, although some serious environmental issues pose a real threat for the lake’s future. Below follows an overview of some of the lake’s most interesting aspects, including its natural beauty, unique inhabitants, and ecological threats.
Cocibolca: an imposing body of water
The indigenous tribes who referred to the lake as Cocibolca (a nahautl word) have most likely used the lake for many practical purposes: the fish supplied food and the fresh water was used for cleaning and consumption. The lake’s water could also serve for irrigation, and the islands inside the lake offered a great, secluded area for living. The Spanish conquerors who first saw the lake thought this immense body of water was a sea, for it has many oceanic qualities: large waves, heavy storms, and nothing but water at the horizon. The lake, one of the largest freshwater lakes in Latin America, has been an important link for many years between inland Nicaragua and the Caribbean Sea, and the colonial city of Granada located on the northwestern shore of the lake was the first Nicaraguan city to be established by Spanish conquerors in 1524. As transportation methods modernized the lake lost importance as strategic link between the Pacific and the Caribbean, but its natural beauty and environmental importance remain important qualities not only for Nicaragua but also for Central America.
Lake Nicaragua is part of the largest international drainage basin of Central America, and together with Lake Managua and the San Juan River it forms a tectonic valley with an area of over 41,000 km². The lake itself is not very deep with an average depth of 13 meters. Rainfall and inflow from numerous rivers feed Lake Nicaragua; outflow only occurs at the San Juan River. Despite being situated close to the Pacific Ocean (at some places there is only 20 kilometers between them), there is no direct connection between the lake and this ocean. The San Juan River, however, connects the lake with the Caribbean Sea, located over 100 kilometers west of Lake Nicaragua.
Currently, there are four main port cities located on the shores of Lake Nicaragua: Granada, San Carlos, San Jorge, and San Miguelito. Despite the lake’s size and connections with the Caribbean Sea and the Pacific slope of Nicaragua, the transportation system is rather poorly developed.
Islands and islets
A volcanic chain cuts right through Lake Nicaragua, and this has resulted in the creation of many beautiful islands and groups of islets. Probably the most famous island is Ometepe, a 276 km² tropical island located 10 kilometers off the mainland at the western side of the lake. The island is composed of two volcanoes: Maderas and Concepción. These two impressive volcanoes are surrounded by fertile soil where nature abounds. For sport and adventure the island offers a great array of possibilities, including volcano hiking, biking, surfing, fishing, kayaking, and swimming. The tropical forests and natural reserves make it furthermore a great place for hikers and nature lovers. Tourism infrastructure is available; see also our Hotel and Restaurant Guides.
Another volcanic island is situated not far away from Ometepe, and even closer to the mainland. Zapatera is the name of this island, and like Ometepe Island this was another indigenous sanctuary. Hundreds if not thousands of artifacts have been found here, and pre-Columbian statues and other objects from Zapatera are now on display at several museums. Official, thorough scientific investigations of these archeological objects have never taken place though, and the island remains fairly unexplored. A few small settlements are present at this rather undeveloped island. Some basic lodging possibilities offer visitors the opportunity to enjoy the stunning beauty of the untouched nature, superb panoramic views, and rustic lifestyle of the inhabitants. More about lodging and activities can be found in our travel guides.
In the same area a famous group of islets can be found: the Granada islets (isletas de Granada in Spanish). Most likely formed by volcanic activity of the nearby Mombacho Volcano, the 365 islets vary significantly in size and are one of Granada’s principal attractions. They are located around the long, narrow Asese peninsula. A whole community lives on the islands, and boats obviously form the most important transportation method as houses, schools, and shops are spread out over many different islets. Some islets feature hotels or restaurants, and luxurious vacation houses on a private islet are also seen more and more often. The main activity at the islets is to rent a boat and take a tour among the Granada islets. Enjoying the tropical sun while cruising around palm-covered islets and observing spectacular views and beautiful birds is definitely a great holiday activity!
Heading to the southeast corner of the lake there is another interesting group of islands worth a visit. The Solentiname archipelago consists of 36 islands, again with a volcanic origin. Some are inhabited; others are tree-covered, uninhabited bird and wildlife sanctuaries. The rustic communities living on various islands of the archipelago have dedicated themselves to creating a unique style of art. The so-called primitive art consist of bright colors and simple shapes and figures, used in paintings and handicrafts. Not only does a visit to the archipelago offer a possibility to observe these artists at work, it also provides visitors a glimpse at the stunning beauty of the islands’ nature. Forested hills, spectacular wildlife, and an amazing variety of birds can all be found here. There is also some tourism infrastructure available at the Solentiname archipelago.
Another interesting group of islands is found at the northeastern side of the lake. Here, in the department of Chontales, there is another island archipelago located not far from the shore. This archipelago, called Nancital, can be reached from the La Orqueta port in Acoyapa. Development of these islands is still in its early stage, and although interest is growing most islands house not much more but a small building, hut, or just trees and birds. Some islands are just for cattle grazing. Several house owners offer their place for rent to tourists.
There are even more islands located in the lake due to the strong volcanic activity that has taken place in this area. The other islands, however, are generally privately owned and can not be (easily) accessed by tourists.
Nature in and around Lake Nicaragua
Environmentally, Lake Nicaragua is a key element in the Nicaraguan landscape. Not only does the lake provide a habitat for spectacular aquatic wildlife, it is also an important water source for the vegetation located on the banks of the lake. With a perimeter of 425 kilometers there is plenty of coastline and several types of ecosystems can be found along the lake’s shores. To the south and southwest there is moist tropical forest, and tropical dry forest vegetates to the east, north, and west of Lake Nicaragua. Parts of this tropical dry forest, however, have been replaced by second-growth forest and agricultural land.
There is dense vegetation at most islands and islets. This generally consists of tropical dry forest, but at the top of two volcanoes (Maderas on Ometepe Island and Mombacho on the shores of the lake, close to Granada) there is a unique ecosystem present. These are the only two places where cloud forest can be found on the Pacific side of Nicaragua, and the flora and fauna at both volcano peaks is definitely impressive.
Thousands of different animal species live within Lake Nicaragua. The most easily observable animals are birds that feed off the fish, plants, and water animals in the lake. Throughout the whole lake birds can be found, but they are especially abundant around the islands and islets. Wading birds like egrets and herons often graciously stand on the waterside, and large groups of cormorants can be seen hunting for fish or standing still in the sun, drying their plumage. Birds of prey like the hawks and kites also hunt around the lake. Hundreds of other bird species can be found in the area, but birders will find the greatest varieties and numbers of birds at places like Río Istián on Ometepe Island, around the Solentiname Archipelago, and at the Granada Islets.
The uninterrupted water surface of Lake Nicaragua allows strong wind to build up as it reaches land. Particularly on the western shore of the lake strong winds can prevail, and it is due to this characteristic that several windmill projects are currently being investigated. Given Nicaragua’s dependability on oil imports for electricity production, such projects are certainly worth looking into, as they can lower electricity prices and create a more sustainable and less polluting source of energy. With over 100 kilometers of windy lakeside, there are definitely many possibilities.
Perhaps the most interesting aspect of the nature in and around Lake Nicaragua is the wildlife living inside the lake. For hundreds if not thousands of years the lake has provided people living in the area an important source for fish. More than 40 different fish species live in Lake Nicaragua, including 16 species of cichlids. In a 1995 report scientists estimated native cichlids to constitute 58% of the lake’s biomass. They also noted that these species were the most heavily exploited so their share might have dropped since then.
The lake’s most famous inhabitant, however, is the so-called freshwater shark. This shark, Carcharhinus leucas, is generally known as the Caribbean bull shark. The shark’s high tolerance of fresh water enabled the predator to adapt to the water of the San Juan River. This allowed the shark to travel up the river and even reach Lake Nicaragua. The sharks would go back and forth to the sea, though. Over time, younger generations better and better adapted to the fresh water until the species was able to reproduce in fresh water, and there was no more need to travel back to the salty Caribbean waters. The freshwater shark became a permanent inhabitant of the San Juan River and Lake Nicaragua, and because of its aggressive behavior (the bull shark is known to attack people) local fishermen and inhabitants strongly feared this new resident. However, during the Somoza dynasty a shark-fin processing plant was built on the shores of the San Juan River. Thousands and thousands of sharks were caught and killed each year at this Japanese plant, and the shark population sharply declined. Nowadays, few sharks remain and this fish is no longer a feared predator in Lake Nicaragua. In fact, the animal has become more of a legendary figure that is often mentioned in reference to the lake without being actually seen anymore. The last media reports of a sighting date back to the year 2000, and although inhabitants of the San Juan River banks report to see sharks every now and then, there have been few recent scientific investigations and the shark population is considered to be virtually wiped out.
Other interesting but endangered fish include the big sawfish (Pristis perotteti) and the fine-toothed sawfish (Pristis pectinatus). The gaspar, another sawfish-like species, is traditionally eaten by Nicaraguans during the Holy Week celebrations.
Ecological threats and environmental issues
Despite the enormous ecosystem in and around the lake, despite being an important potential source for potable water and despite its large attraction for ecological and sustainable tourism Lake Nicaragua does face problems of contamination that could become much worse in the middle-long term (and some in the short term as well) if necessary steps to prevent so are not taken. Even though this situation has been publicly acknowledged by institutions, organizations, experts, and citizens there is not yet a national plan that addresses conservation of this beautiful lake.
There are three principal contamination threats and although at this time all three of them can be controlled or eliminated it does require effort and commitment by all parties and authorities involved, as well as support of the population.
The main problem and source of contamination for Lake Nicaragua are related to the discharge of wastewater that comes from the urban zones at the shores of the lake. In spite of the clear contamination that results from this practice, large cities as Granada, Rivas and Juigalpa and many small towns still lead their sewage from residential areas but even from industrial zones to the lake (either directly or through a river that terminates in the lake). Consequently, coastal areas close to these urban centers have to deal with the waste that is not biodegradable which surfaces in front of the settlements.
The second largest problem comes from the agricultural industry in the coastal areas. The fertile soil next to the lake provides a great site for cattle farming and plantations. In the departments of Chontales, Boaco and Rivas there are many places where people farm without protecting the lake whatsoever, leading to contamination with enormous quantities of fertilizers ending up in the water. Another even more important impact is caused by the nearby agricultural haciendas that contaminate the rivers flowing into the lake by the unprotected usage of chemicals at their plantations. This problem is mostly visible at the southern side of the lake on Nicaraguan territory but also on Costa Rican soil (as these rivers also terminate in Lake Nicaragua).
The third problem is a controversial issue related to the recent introduction of new fish species inside floating cages in the lake. Although the foreign firm that develops this project obtained the governmental permits and even though the fish breeding has already started, there has been strong disapproval by ecologists, social organizations and communities ever since the beginning. The problem, the critics point out, is that the huge quantity of Tilapia fish generates large waste quantities that the lake has to adsorb. The biologists also warn that the Tilapia might bring diseases that the endemic fish are not prepared for.
What is currently necessary is implementation of measures by the national authorities to face the aforementioned problems and to prevent other problems that might threaten the lake in the future. Several organizations are already promoting the idea of preserving and protecting Lake Nicaragua, but so far these issues lack importance on the national agenda.
In addition to the large tourism potential, the lake also has a potential to function as source for potable water for national use and export. The Centrum of Investigations of the Aquatic Resources (Centro de Investigación de los Recursos Acuáticos), CIRA-UNAN, indicates that the lake discharges 478 cubic meters of water per second through the San Juan River (registered by the Nicaraguan Institute of Territorial Studies - INETER). Per day this amounts to 41.3 million cubic meters. This water can become an important renewable source of income if commercialized. The CIRA therefore warns not to let companies and private producers contaminate the lake.
At this moment the UNESCO has already received a petition from the Nicaraguan government to declare Lake Nicaragua World Heritage. The authorities and the hundreds of communities set around the lake have expressed their enthusiasm and hopefully the UNESCO will grant the request. But in order to protect the lake the national and local government, as well as every Nicaraguan citizen and foreigner that wants to enjoy this lake, should become involved and act in order to preserve this natural treasure!
Further Reading and Sources
- Lake Cocibolca/Nicaragua: Experience and Lessons Learned Brief - Lake Basin Management Initiative
- African Tilapia in Lake Nicaragua
- Articles from El Nuevo Diario
- Gran Lago Cocibolca ¿reserva nacional de agua potable para Nicaragua?, Salvador Montenegro Guillén, Professor of the UNAN-Managua and director of the Center of Investigations of the Aquatic Resources (CIRA)