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38-496: Rivas is known for its fertile soil and beaches. Throughout the department, there are many sugar cane, plantain, tobacco, and other crop plantations. The department borders Lake Nicaragua to the east and the Pacific Ocean to the west. The southern part of the department borders with Costa Rica . A small fishermen village, called San Juan del Sur, has turned into a popular tourist attraction because of its access to beaches in

76-477: A tilapia , is used widely in aquaculture within the lake. Owing to the large amount of waste they produce, and the risk of introducing diseases to which the native fish species have no resistance , they are potentially a serious threat to the lake's ecosystem . The nation's largest source of freshwater, Nicaraguans call it Lago Cocibolca or Mar Dulce (literally "Sweet Sea"; in Spanish, "freshwater"

114-415: A clear yellow tinge to the fins. Individuals in freshwater may have a reddish colour caused by blood suffusion below the skin. The underside is greyish or white. The largetooth sawfish can be found worldwide in tropical and subtropical coastal regions, but it also enters freshwater and has been recorded in rivers as far as 1,340 km (830 mi) from the sea. Historically, its East Atlantic range

152-474: A number of conservation projects have been initiated, but the largetooth sawfish has probably already been extirpated from the latter country (last confirmed record in 1961 from Nueces , Texas). Additionally it receives a level of protection in Bangladesh , Brazil, Guinea , India, Indonesia, Malaysia, Mexico, Nicaragua, Senegal and South Africa, but illegal fishing continues, enforcement of fishing laws

190-443: A typical length is 2–2.5 m (6.6–8.2 ft). Large individuals may weigh as much as 500–600 kg (1,102–1,323 lb), or possibly even more. The largetooth sawfish is easily recognized by the forward position of the dorsal fin with its leading edge placed clearly in front of the leading edge of the pelvic fins (when the sawfish is seen from above or the side), the relatively long pectoral fins with angular tips, and

228-502: Is agua dulce ). The lake has sizeable waves driven by the easterly winds blowing west to the Pacific Ocean . The lake holds Ometepe and Zapatera , which are both volcanic islands , as well as the archipelago of the Solentiname Islands . The lake has a reputation for periodically powerful storms. In the past 37 years, considerable concern has been expressed about the ecological condition of Lake Nicaragua. In 1981

266-703: Is a freshwater lake in Nicaragua . Of tectonic origin and with an area of 8,264 km (3,191 sq mi), it is the largest fresh water lake in Central America , the 19th largest lake in the world (by area) and the tenth largest in the Americas , slightly smaller than Lake Titicaca . With an elevation of 32.7 metres (107 ft) above sea level, the lake reaches a depth of 26 metres (85 ft) . The intermittent Tipitapa River feeds Lake Nicaragua when Lake Managua has high water. Lake Cocibolca

304-661: Is between two other bodies of water, on top is Lake Xolotlán and below is the San Juan River. These body of waters complete the largest International Drainage Basin in Central America. The lake drains via the San Juan River flowing east to the Caribbean Sea , historically making the city Granada on the northwest shore an Atlantic port, although Granada (as well as the entire lake) is closer to

342-461: Is derived from the Greek word for saw. The largetooth sawfish possibly reaches up to 7.5 m (25 ft) in total length, but the largest confirmed was a West African individual that was 7 m (23 ft) long. An individual caught in 1951 at Galveston, Texas , which was documented on film but not measured, has been estimated to be of similar size. Today most individuals are far smaller and

380-666: Is lethal. Sexual maturity is reached at a length of about 2.8–3 m (9.2–9.8 ft) when 7–10 years old. Breeding is seasonal in this ovoviviparous species, but the exact timing appears to vary depending on the region. The adult females can breed once every 1–2 years, the gestation period is about five months, and there are indications that mothers return to the region where they were born to give birth to their own young. There are 1–13 (average c. 7) young in each litter, which are 72–90 cm (28–35 in) long at birth. They are likely typically born in salt or brackish water near river mouths, but move into freshwater where

418-697: Is now critically endangered . A range of English names have been used for the species, or populations now part of the species, including common sawfish (despite it being far from common today), wide sawfish , freshwater sawfish , river sawfish (less frequently, other sawfish species also occur in freshwater and rivers), Leichhardt's sawfish (after explorer and naturalist Ludwig Leichhardt ) and northern sawfish . The taxonomy of Pristis pristis in relations to P. microdon (claimed range: Indo-West Pacific ) and P. perotteti (claimed range: Atlantic and East Pacific) has historically caused considerable confusion, but evidence published in 2013 revealed that

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456-652: Is of sufficient size to be viable , but even it has experienced a decline. Other places in the Indo-Pacific where still present, even if in very low numbers, are off Eastern Africa, the Indian subcontinent and Papua New Guinea , and in the East Pacific it survives off Central America, Colombia and northern Peru. Whether it survives anywhere in Southeast Asia is generally unclear, but one was captured in

494-514: Is relatively wide compared to the other sawfish species, and there are 14–24 equally separated teeth on each side of it. On average, females have shorter rostrums with fewer teeth than males. The rostral teeth are large and grooved from base to tip. The proportional rostrum length also varies with age, with average being around 27% of the total length of the fish, but can be as high as 30% in juveniles and as low as 20–22% in adults. Its upperparts are generally grey to yellowish-brown, often with

532-543: The Ministry of the Environment and Natural Resources (MARENA) conducted an environmental assessment study and found that half of the water sources sampled were seriously polluted by sewage . It was found that 32 tons (70,000 pounds) of raw sewage were being released into Lake Nicaragua daily. Industry located along the lake's shore had been dumping effluent for an extended period of time. Pennwalt Chemical Corporation

570-526: The Pacific Ocean geographically. The Pacific is near enough to be seen from the mountains of the largest island in the lake, Ometepe . The lake has a history of Caribbean pirates who assaulted Granada on three occasions. Before construction of the Panama Canal, a stagecoach line owned by Cornelius Vanderbilt 's Accessory Transit Company connected the lake with the Pacific across the low hills of

608-541: The "saw" they are particularly prone to becoming entangled in fishing nets. Historically sawfish were also persecuted for the oil in their liver. In the Niger Delta region of southern Nigeria , sawfish (known as oki in Ijaw and neighbouring languages) are traditionally hunted for their saws, which are used in masquerades . The largetooth sawfish has been extirpated from many regions where formerly present. Among

646-463: The "saw". As suggested by the alternative name common sawfish, it was once plentiful, but has now declined drastically leading to it being considered a critically endangered species by the IUCN . The main threat is overfishing, but it also suffers from habitat loss. Both their fins (used in shark fin soup ) and "saw" (as novelty items) are highly valuable, and the meat is used as food. Because of

684-555: The 1970s when tens of thousands were caught. It has been protected in Nicaragua since the early 1980s, but remains rare in the lake today, and is now threatened by the planned Nicaragua Canal . In West Africa, the Bissagos Archipelago has often been considered the last remaining stronghold, but interviews with locals indicate that sawfish now also are rare there. All sawfish species were added to CITES Appendix I in 2007, thereby restricting international trade. As

722-417: The 75 countries where recorded historically, it has disappeared from 28 and may have disappeared from another 27, leaving only 20 countries where certainly still present. In terms of area this means that it certainly survives in only 39% of its historical range. Only Australia still has a relatively healthy population of the species and this may be the last remaining population in the entire Indo-Pacific that

760-481: The Mediterranean dates back to 1959. Adults are primarily found in estuaries and marine waters to a depth of 25 m (82 ft), but mostly less than 10 m (33 ft). Nevertheless, the species does appear to have a greater affinity for freshwater habitats than the smalltooth sawfish ( P. pectinata ), green sawfish ( P. zijsron ), and dwarf sawfish ( P. clavata ). Largetooth sawfish from

798-635: The Philippines in 2014 (a country where otherwise considered extirpated). The species has disappeared from much of its Atlantic range and declined where still present. The likely largest remaining population in this region is in the Amazon estuary, but another important population is in the San Juan River system in Central America. It was once abundant in Lake Nicaragua (part of the San Juan River system), but this population rapidly crashed during

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836-779: The United States , a review indicates that only those from Texas are genuine. Other specimens, notably several claimed to be from Florida , were likely imported from other countries. Its East Pacific range was from Peru to Mazatlán in Mexico. Historically it was widespread in the Indo-Pacific, ranging from South Africa to the Horn of Africa , India, Southeast Asia and Northern Australia . Its total distribution covered almost 7,200,000 km (2,800,000 sq mi), more than any other species of sawfish, but it has disappeared from much of its historical range. The last record taken in

874-581: The area. Another major tourist attraction is Ometepe , a large volcanic island inhabited by about 32,000 people (2005 census). Nawat Nicarao people still inhabit the department. 11°26′52″N 85°34′17″W  /  11.44778°N 85.57139°W  / 11.44778; -85.57139 This Nicaragua location article is a stub . You can help Misplaced Pages by expanding it . Lake Nicaragua Lake Nicaragua or Cocibolca or Granada ( Spanish : Lago de Nicaragua , Lago Cocibolca, Mar Dulce, Gran Lago, Gran Lago Dulce , or Lago de Granada )

912-399: The canal as well as questions about financing led to doubts about the project, and in the end construction never began. Lake Nicaragua, despite being a freshwater lake, has sawfish , tarpon , and sharks . Initially, scientists thought the sharks in the lake were an endemic species, the Lake Nicaragua shark ( Carcharhinus nicaraguensis ). In 1961, following comparisons of specimens , it

950-757: The first marine fish, there was an attempt of having it listed under the Endangered Species Act (ESA) in 2003 by the United States National Marine Fisheries Service , but it was declined. However, it was listed as P. perotteti under the ESA in 2011. Following taxonomic changes, the ESA listing was updated to P. pristis in December 2014. Sawfish are protected in Australia and the United States where

988-666: The idea of another canal in Nicaragua still periodically resurfaced, such as the Ecocanal proposal . In 2014, the government of Nicaragua offered a 50-year concession to the Hong Kong Nicaragua Canal Development Investment Company (HKND) to build a canal across Nicaragua at a cost of US$ 40 billion, with construction expected to begin in December 2014 and complete in 2019. Protests against the ecological and social effects of

1026-410: The lake could lead to saltwater and other contamination during construction and operation of the canal. Largetooth sawfish The largetooth sawfish ( Pristis pristis , syn. P. microdon and P. perotteti ) is a species of sawfish in the family Pristidae . It is found worldwide in tropical and subtropical coastal regions, but also enters freshwater. It has declined drastically and

1064-422: The lake have later been caught in the open ocean (and vice versa), with some taking as little as 7–11 days to complete the journey. Numerous other species of fish live in the lake, including at least 16 cichlids that are endemic to the general region. None of these are strictly endemic to Lake Nicaragua, although Amphilophus labiatus is native only to Lake Nicaragua and Lake Managua . A non-native cichlid,

1102-430: The largetooth sawfish is unknown, but four estimates suggested 30 years, 35 years, 44 years, and 80 years. The largetooth sawfish is a predator that feeds on fish, molluscs and crustaceans. The "saw" can be used both to stir up the bottom to find prey and to slash at groups of fish. Sawfish are docile and harmless to humans, except when captured where they can inflict serious injuries when defending themselves with

1140-609: The narrow Isthmus of Rivas . Plans were made to take advantage of this route to build an Interoceanic Canal , the Nicaragua Canal , but the Panama Canal was built instead. In order to quell competition with the Panama Canal, the U.S. secured all rights to a canal along this route in the Bryan–Chamorro Treaty of 1916. However, since this treaty was mutually rescinded by the United States and Nicaragua in 1970,

1178-561: The population in Lake Nicaragua appear to spend most, if not all, of their life in freshwater, but tagging surveys indicate that at least some do move between this lake and the sea. Captive studies show that this euryhaline species can thrive long-term in both salt and freshwater, regardless of its age, and that an acclimation from salt to freshwater is faster than the opposite. In captivity they are known to be agile (even swimming backwards), have an unusual ability to "climb" with

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1216-416: The presence of a small lower tail lobe. In all other sawfish species the leading edge of their dorsal fin is placed at, or behind, the leading edge of the pelvic fins, and all other Pristis sawfish species have shorter pectoral fins with less pointed tips and lack a distinct lower tail lobe (very small or none). The rostrum ("saw") of the largetooth sawfish has a width that is 15–25% of its length, which

1254-404: The three are conspecific , as morphological and genetic differences are lacking. As a consequence, recent authorities treat P. microdon and P. perotteti as synonyms of P. pristis . Based on an analysis of NADH -2 genes there are three main clades of P. pristis : Atlantic, Indo-West Pacific and East Pacific. Its scientific name Pristis (both the genus and specific name)

1292-475: The use of the pectoral fins and they can jump far out of the water; a 1.8-metre-long (5.9 ft) individual jumped to a height of 5 m (16 ft). It has been suggested that this may be adaptions for traversing medium-sized waterfalls and rapids when moving upriver. They are generally found in areas with a bottom consisting of sand, mud or silt. The preferred water temperature is between 24 and 32 °C (75–90 °F), and 19 °C (66 °F) or colder

1330-426: The young spend the first 3–5 years of their life, sometimes as much as 400 km (250 mi) upriver. In the Amazon basin the largetooth sawfish has been reported even further upstream, and this mostly involves young individuals that are up to 2 m (6.6 ft) long. Occasionally, young individuals become isolated in freshwater pools during floods and may live there for years. The potential lifespan of

1368-554: Was synonymized with the widespread bull shark ( C. leucas ), a species also known for entering freshwater elsewhere around the world. It had been presumed that the sharks were trapped within the lake, but this was found to be incorrect in the late 1960s, when it was discovered that they were able to jump along the rapids of the San Juan River — which connects Lake Nicaragua with the Caribbean Sea — almost like salmon . As evidence of these movements, bull sharks tagged inside

1406-478: Was found to be the worst polluter. Nicaragua's economic situation has hampered the building of treatment facilities nationwide (see: Water supply and sanitation in Nicaragua ). The country's worst drought in 32 years took its toll on the lake in 2014; the Nicaraguan government recommended citizens to raise and eat iguanas over chickens to reduce water consumption. Also, plans for the Nicaragua Canal through

1444-591: Was from Mauritania to Angola . There are old reports (last in the late 1950s or shortly after) from the Mediterranean and these have typically been regarded as vagrants , but a review of records strongly suggests that this sea had a breeding population. Its West Atlantic range was from Uruguay to the Caribbean and the Gulf of Mexico . Although there are claimed reports from several Gulf Coast states in

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