Showing posts with label Lakes. Show all posts
Showing posts with label Lakes. Show all posts

Tuesday, December 5, 2017

Freshwater sharks in Lake Cocibolca (Lake Nicaragua)

In the coastal and volcanic regions of America, lake landscapes abounded. There were lakes in the Purépecha country of Michoacán, in the Otomi and Nahua central region of Mexico, in the volcanic plateaus and valleys of the Mayan country, in the Lenca and Guatuso lands of Central America, and further south, in the coasts, mountains and plateaus of the South American continent.
These lakes were privileged sites for human occupation. In addition to supplying fresh water for towns and cities, they contained very rich ecosystems with fish, birds, invertebrates and aquatic plants that could provide food for many people.
On the shores of the lakes, fishing villages were established, which in addition to fishing took advantage of other resources of the lacunar environment, such as crustaceans, mollusks, batrachians, algae or plant fibers.
In Mesoamerica progress was made in the use of lacunar waters and a productive agriculture was developed by means of floating gardens, called chinampas in the Mexican lakes.
In larger bodies of water, such as the lakes of the Anahuac valley in the Mexican plateau, lake Titicaca in the Peruvian-Bolivian plateau and Lake Cocibolca in Nicaragua, lake surfaces provided an adequate environment for navigation and trade between the coastal regions. In many ways these lakes represented prosperity and abundance and allowed the development of complex societies with dense demographic concentrations and high productivity.
European colonization produced profound changes in the relationship of populations with the interior waters of the continent. After five centuries of Creole occupation of the lacunar coasts, the landscape is no longer the same.
Many lakes in America have suffered human predation. Some have disappeared. Others have been reduced to a minimal expression. There are lakes that are polluted and do not harbor animal life in their waters. And finally there are the degraded, who have lost diversity, with extinct or endangered species.
The Great Lake of Nicaragua, called Cocibolca by the Nahuas and Ukurikitucara by the Guatusos and Matagalpas was for a long time home to sharks. It was a unique species of freshwater sharks. The scientists called him Carcharhinus nicaraguensis.
It is a species that is closely related to the Bull Shark that abounds in tropical seas.
The studies made it possible to verify that the Shark of the Lake migrated by the San Juan River to the Caribbean, in the style of the salmon, and then returned. This was confirmed by means of some labeled specimens.
Formerly the species was very abundant. Although there were stories about their aggressiveness, attacks on people, the danger they could represent, in fact it was a fairly harmless fish.
In 2004, it was reported that in the waters of the San Juan River, a massacre of the species was occurring as a result of the very high price paid for the fin of the animal in Japan and other countries in the East. The figure of $ 256 per pound (more than $ 500 per kilogram) was mentioned. The indiscriminate fishing continues and it is thought that the shark of the lake is about to become extinct.
Or maybe it's already extinct.
Reproduced from "Chronicles of Human Peripecy", Danilo Antón, Piriguazú Ediciones

Tuesday, July 18, 2017

Freshwater sharks in the Ukurikitucara lake
Danilo Anton

In the coastal and volcanic regions of America the lake landscapes abounded in the past. There were lakes in the Purépecha country of Michoacan, in the central region of Mexico where Otomi and Nahuas lived and there were lakes on the plateaus and volcanic valleys of the Maya country. There were also many lakes  in the lands of the Lencas and Guatusos of Central America, and even further south, in the coasts, mountains and plateaus of the South American continent.
These lakes were privileged places for human occupation. In addition to supplying fresh water to towns and cities, they contained very rich ecosystems with fish, birds, invertebrates and aquatic plants that could provide food for many people.
On the shores of the lakes, fishing villages were established which, in addition to fishing, took advantage of other resources of the lagoon environment, such as crustaceans, molluscs, batrachians, algae or plant fibers.

In Mesoamerica, more progress was made in the use of lacunar waters and productive agriculture was developed through floating orchards, which mexicans nahuatl called chinampas.
In the larger bodies of water, such as the lakes of the Anahuac valley on the Mexican plateau, Lake Titicaca on the Peruvian-Bolivian plateau, and Lake Cocibolca in Nicaragua the wide lake surfaces provided an adequate environment for navigation and trade between the coastal regions. In many ways these lakes represented prosperity and abundance and allowed the development of complex societies with dense population concentrations and high productivity.
European colonization produced profound changes in the relation of populations to the interior waters of the continent. After five centuries of foreign occupation of the lacunar coasts, the landscape is no longer the same.

Many lakes in America have suffered from human predation. Some have disappeared. Others have been reduced to a minimum expression. There are lakes that are contaminated and do not harbor animal life in their waters. And finally there are those that have been degraded, who have lost diversity, with species extinct or in the process of extinction.
The Great Lake of Nicaragua, called Cocibolca by the nahuas and Ukurikitucara by the guatusos and matagalpas was long home of sharks. It was a unique species of freshwater sharks. The scientists called him Carcharhinus nicaraguensis.
It is a species that is closely related to Torus Shark that abounds in tropical seas.
The studies made it possible to verify that the lake shark migrated along the San Juan River to the Caribbean, in the style of salmon, and then returned. This was ratified by means of some tagged specimens.
In ancient times the species was very abundant. While there were stories about their aggressiveness, attacks on people, the danger they could pose, in fact it was a fairly harmless fish.
In 2004 it was reported that in the waters of the San Juan River a massacre of the species was occurring as a consequence of the very high price that was paid for the fin of the animal in Japan and other countries of the East. The figure was $ 256 per pound (more than $ 500 a kilogram). Indiscriminate fishing is still going on and it is thought that the lake shark is about to die out.
Or maybe it's gone.
From: "Chronicles of Human Peripecie", D.Anton, Piriguazu Ediciones.