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Observations On The Reproduction Of The Sawfish, Pristis Perotteti, In Lake Nicaragua, With Recommendations For Its Conservation, Thomas B. Thorson
Observations On The Reproduction Of The Sawfish, Pristis Perotteti, In Lake Nicaragua, With Recommendations For Its Conservation, Thomas B. Thorson
Investigations of the Ichthyofauna of Nicaraguan Lakes
The presently known pristiform fauna of the western Atlantic consists of only two species, one each of Fowler's (1941) subgenera, Pristis and Pristiopsis. The former, characterized by the absence of a subcaudal lobe on the caudal fin, is represented by Pristis pectinatus; the latter, in which the subcaudal lobe is present, by Pristis perotteti. Although several features readily separate the two species, they can most easily be distinguished by the more slender rostrum of P. pectinatus and its larger number of rostral teeth, 24 to 32 on each side, as compared with 14 to 20 in P. …
Index Of Scientific Names
Investigations of the Ichthyofauna of Nicaraguan Lakes
Index of scientific names in Investigations of the Ichthyofauna of Nicaraguan Lakes.
The Midas Cichlid In Nicaragua, George W. Barlow
The Midas Cichlid In Nicaragua, George W. Barlow
Investigations of the Ichthyofauna of Nicaraguan Lakes
Cichlasoma citrinellum (Gunther), the Midas cichlid, is the most important food fish in the Great Lakes Basin of Nicaragua. It occurs in the majority of the lakes, where it is the most ubiquitous cichlid fish, but it is uncommon in the rivers. The fry are carnivorous while the juveniles and adults are omnivorous, eating mostly Aufwuchs, snails, and fish. The Midas cichlids suffer from a number of diseases in nature and in the laboratory, including lymphocystis and nocardiosis. Potential predators vary from sharks and sawfish in Lake Nicaragua, to just one cichlid relative in one crater lake; in Lake …
Ontogeny Of Parent-Contacting In Young Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes, George W. Barlow
Ontogeny Of Parent-Contacting In Young Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes, George W. Barlow
Investigations of the Ichthyofauna of Nicaraguan Lakes
There is an extensive literature on cichlid fish behavior, but most of this treats the behavior of adults (see BREDER & ROSEN, I966, for example). Much of this is based on laboratory observations with little corroborative information from field studies. Recently there has been an increasing trend to study the development of behavior, in cichlids as in other animals. In part this results from the 'nature-nurture' controversy regarding factors control~ ling behavior (e.g. KRUIJT, I964). However, there is also interest in the study of young animals for their own sake (e.g. WARD & BARLOW, I967).
The present study was undertaken …
The Status Of The Lake Nicaragua Shark: An Updated Appraisal, Thomas B. Thorson
The Status Of The Lake Nicaragua Shark: An Updated Appraisal, Thomas B. Thorson
Investigations of the Ichthyofauna of Nicaraguan Lakes
Since 1966, an extensive tagging program has demonstrated beyond any further doubt (Thorson, 1971) that the sharks move from the Caribbean Sea to Lake Nicaragua and vice versa. At the time of this writing, of 1450 post-juvenile sharks tagged at the various river mouths on the Caribbean Coast, ten have been recovered in Lake Nicaragua; and of 146 tagged at San Carlos, where the river leaves the lake, 28 have been recovered along the Caribbean Coast, most of them at the various outlets of the Rio San Juan. Except for these basic facts, the results of the tagging program have …
Rectal Glands Of Marine And Fresh-Water Sharks: Comparative Histology, Mikio Oguri
Rectal Glands Of Marine And Fresh-Water Sharks: Comparative Histology, Mikio Oguri
Investigations of the Ichthyofauna of Nicaraguan Lakes
The rectal glands of elasmobranchs perform the function of salt-excreting organs. These glands are smaller and show regressive changes in specimens of the bull shark, Carcharhinus leucas, found in fresh-water environment, compared with specimens of this and other species from a marine habitat.
Chemical Analyses Of Some Crater Lakes In Relation To Adjacent Lake Nicaragua, George W. Barlow, Jeffrey R. Baylis, Dale Roberts
Chemical Analyses Of Some Crater Lakes In Relation To Adjacent Lake Nicaragua, George W. Barlow, Jeffrey R. Baylis, Dale Roberts
Investigations of the Ichthyofauna of Nicaraguan Lakes
In spite of the wide interest by naturalists in the Great Lakes of Nicaragua their limnology has received little study. Cole (1976) has reviewed the literature and contributed new data and interpretations. Our paper adds to his larger work by presenting chemical analyses of Lake Nicaragua and some of the small crater lakes near it. These smaller lakes have been neglected. The only information published about them is a fragmentary table in Riedel (1964), giving some comparative data on surface area, circumference, and depth.
The Origin Of The Lakes In The Nicaraguan Fault And Of The Middle American Isthmus In The Light Of Studies Of The Fish Fauna, Dietmar Riedel
The Origin Of The Lakes In The Nicaraguan Fault And Of The Middle American Isthmus In The Light Of Studies Of The Fish Fauna, Dietmar Riedel
Investigations of the Ichthyofauna of Nicaraguan Lakes
The geological hypothesis of a marine origin of the Nicaraguan depression and its lakes was until the fifties of the present century exclusively based upon the occurrence of marine species (shark, sawfish and tarpon) in Lake Nicaragua. A recent view, however, is that the fault was never connected with the sea and that the lakes were filled by rain only.
In view of the fact that there seems to be no agreement among geologists about the geological history of the Nicaraguan depression, an attempt is made to contribute to the discussion by evaluating the fish faunal elements of the fault. …
Geographical Distribution Of Central American Freshwater Fishes, Robert Rush Miller
Geographical Distribution Of Central American Freshwater Fishes, Robert Rush Miller
Investigations of the Ichthyofauna of Nicaraguan Lakes
The distribution of freshwater fishes in Central America is reviewed. Major parts of the region, especially in Honduras and Nicaragua, have yet to be explored ichthyologically, and systematic revision of important groups, notably the cichlids, is long overdue. The continental area from the Isthmus of Tehuantepec to the Colombian border contains approximately 456 species, of which over 75% comprise the Cyprinodontidae, Poeciliidae, Cichlidae, and marine invaders (peripheral fishes); about one-third of the latter (57 species) have taken up more or less permanent residence in fresh water. There are 104 primary species in 10 families, 165 secondary forms in 6 families, …
Geographic Distribution Of The San Juan Ichthyofauna Of Central America With Remarks On Its Origin And Ecology, William A. Bussing
Geographic Distribution Of The San Juan Ichthyofauna Of Central America With Remarks On Its Origin And Ecology, William A. Bussing
Investigations of the Ichthyofauna of Nicaraguan Lakes
The scientific study of fishes of the Great Lakes of Nicaragua began in 1864 with the description by Gunther of Heros labiatus (=Cichlasoma labiatum) from Lake Managua. Subsequently, Gunther reported on several other species collected in the Great Lakes by Captain J. M. Dow. Astorqui (1967) reviewed the sparse ichthyological literature dealing with Nicaraguan fishes and pointed out the paucity of recent studies. Since then Villa (1971) has produced a provisional list of the freshwater and brackish water fishes of Nicaragua and Astorqui (1972) has analyzed the ichthyofauna of the Great Lakes Basin. Riedel (1972) discussed the geological …
Lake Nicaragua Fishery Resources, William D. Davies
Lake Nicaragua Fishery Resources, William D. Davies
Investigations of the Ichthyofauna of Nicaraguan Lakes
Data collected during this survey indicated that the number of full-time fishermen has not increased appreciably over the past several years. However, it is likely that, if the demand for fish were to increase, a number of the present part-time fishermen would increase their effort to full-time. Indications are strong that the fish catch from this lake could at least be doubled by the existing population of fishermen, using the same gear, if market conditions were such as to encourage greater fishing effort.
The lake's overall fisheries resources are far from being exploited to their maximum, with the possible exception …
Species Diversity And Distribution Of Fish In Lake Nicaragua, Kurt W. Koenig, Richard J. Beatty, Sergio Martinez C.
Species Diversity And Distribution Of Fish In Lake Nicaragua, Kurt W. Koenig, Richard J. Beatty, Sergio Martinez C.
Investigations of the Ichthyofauna of Nicaraguan Lakes
The results of a preliminary study of the abundance, diversity and distribution of some of the fish species in Lake Nicaragua are presented here. These parameters have received little attention from investigators working on the lake.
A frequently used measure of species diversity is the Shannon-Weiner diversity index. It measures the degree of uncertainty of predicting the species identity of a randomly selected individual (Pielou, 1966). Lloyd and Ghelardi (1964) indicated that species diversity indices are influenced by both the species number, or "richness", and the species "evenness", or relative number of individuals of a species in a given habitat. …
La "Pepesca Gaspar", Otro Pez Desconocido Del Gran Lago, Jaime Villa
La "Pepesca Gaspar", Otro Pez Desconocido Del Gran Lago, Jaime Villa
Investigations of the Ichthyofauna of Nicaraguan Lakes
En un articulo recientemente aparecido, informe sobre la presencia de un pez hasta entonces desconocido en el Lago de Nicaragua, el gimnoto cilindrico. Existen, sin embatgo, varias especies adicionales que he ido descubriendo poco a poco y que ire presentando de igual modo al publico lector.
The Red Devil-Midas-Arrow Cichlid Species Complex In Nicaragua, George W. Barlow, John W. Munsey
The Red Devil-Midas-Arrow Cichlid Species Complex In Nicaragua, George W. Barlow, John W. Munsey
Investigations of the Ichthyofauna of Nicaraguan Lakes
Within this group (section Amphilophus) of Nicaraguan cichlid fishes, we recognize two of the eight named species, Cichlasoma labiatum (Günther) and C. citrinellum (Günther). A new species from Lake Apoyo, C. zaliosum Barlow, is described. The red devil cichlid (C. labiatum) occurs only in the Great Lakes, but the Midas cichlid (C. citrinellum) is found in most of the surrounding lakes as well, and also in Costa Rica; where the two species are sympatric they differ most from one another. In Lakes Masaya and Jiloá some individuals of C. citrinellum show features of C. labiatum …
Relative Abundance And Distribution Of The Mojarra (Cichlasoma Citrinellum) In Lake Nicaragua, Sergio Martínez C
Relative Abundance And Distribution Of The Mojarra (Cichlasoma Citrinellum) In Lake Nicaragua, Sergio Martínez C
Investigations of the Ichthyofauna of Nicaraguan Lakes
Sixteen families and at least forty-five species of fishes have been reported from Lake Nicaragua (Astorqui, 1971; Villa, 1971). The National Development Institute of Nicaragua (INFONAC) has investigated the potential fish resources and their distribution in the lake in order to implement a program of development and a rational management of the fisheries of the lake (INFONAC, 1974). The study at hand was conducted in connection with that investigation to define the abundance and natural habitat of the mojarra, Cichlasoma citrinellum. This fish belongs to the family Cichlidae, which is represented in the lake by several species.
Cichlasoma …
Cross-Fostering And Parent-Offspring Responses In Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes, George W. Barlow
Cross-Fostering And Parent-Offspring Responses In Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes, George W. Barlow
Investigations of the Ichthyofauna of Nicaraguan Lakes
Previous studies of parent-young interactions in cichlid fish have established some of the details of such relations, but have raised, or left unanswered many questions. In particular, there are questions as to the recognition of parents and young by each other, and to what extent learning might be involved in such recognition.
Based on observations of exchanges of parents between families of Cichlasoma citrinellum, we suggest that parents learn to recognize young during each parental cycle. They appear to have a moderately short term memory for recognition of young, and accept young corresponding to this memory.
Parental fish accept …
Competition Between Color Morphs Of The Polychromatic Midas Cichlid Cichlasoma Citrinellum, George W. Barlow
Competition Between Color Morphs Of The Polychromatic Midas Cichlid Cichlasoma Citrinellum, George W. Barlow
Investigations of the Ichthyofauna of Nicaraguan Lakes
The Midas cichlid, Cichlasoma citrinellum, is a polychromatic fish that occurs in Nicaragua. All of these fish start life as normally colored, cryptic individuals. In some populations a few fish change into conspicuously colored morphs, most frequently gold. When kept in unmixed color groups, golds and normals grow at the same rate; but when they are mixed, growth of the golds becomes taster and that of the normals slower. Golds dominate normals in contests over food, which accounts for their advantage.
Competition Between Color Morphs Of The Midas Cichlid, Cichlasoma Citrinellum, In Lake Jiloá, Nicaragua, Kenneth R. Mckaye, George W. Barlow
Competition Between Color Morphs Of The Midas Cichlid, Cichlasoma Citrinellum, In Lake Jiloá, Nicaragua, Kenneth R. Mckaye, George W. Barlow
Investigations of the Ichthyofauna of Nicaraguan Lakes
Color polymorphism, or polychromatism, is a recurring phenomenon throughout the animal kingdom. In fishes one form, the goldfish, is particularly notable because of its conspicuousness and its occurrence in nature in such a large number of widely unrelated species; yet it is seldom common in anyone species (Webber et al., 1973). The Midas cichlid, Cichlasoma citrinellum, is unusual in this respect because in many of the lakes where it occurs in Nicaragua brilliantly colored morphs are relatively common. These morphs lack the species-typical dark markings, and individuals vary smoothly from white through yellow, orange, red, and mixtures of …
The Behavior And Ecology Of Herotilapia Multispinosa (Teleostei, Cichlidae), Jeffrey R. Baylis
The Behavior And Ecology Of Herotilapia Multispinosa (Teleostei, Cichlidae), Jeffrey R. Baylis
Investigations of the Ichthyofauna of Nicaraguan Lakes
Because of their complex social behavior and the ease with which they can be manipulated, cichlid fishes have long been of special interest to the ethologist. However, most of the research into cichlid behavior has been on Old World species. The social behavior of New World species is different and deserves more study. This paper will describe the ethology of one of the Central American cichlids, Herotilapia multispinosa.
Carcharhinus Nicaraguensis, A Synonym Of The Bull Shark, C. Leucas, Henry B. Bigelow, William C. Schroeder
Carcharhinus Nicaraguensis, A Synonym Of The Bull Shark, C. Leucas, Henry B. Bigelow, William C. Schroeder
Investigations of the Ichthyofauna of Nicaraguan Lakes
Nicaraguensis very closely resembles leucas by the following characters. The anterior margin of the eye is posterior to the front of the mouth by a distance equal to half its own diameter in nicaraguensis; the gill openings are relatively somewhat longer in nicaraguensis, the third being nearly as long as the distance between the nostrils; the free tip of the second dorsal is about two-thirds as long as its base in nicaraguensis.
Movement Of Bull Sharks, Carcharhinus Leucas, Between Carribean Sea And Lake Nicaragua Demonstrated By Tagging, Thomas B. Thorson
Movement Of Bull Sharks, Carcharhinus Leucas, Between Carribean Sea And Lake Nicaragua Demonstrated By Tagging, Thomas B. Thorson
Investigations of the Ichthyofauna of Nicaraguan Lakes
The shark that occurs in the fresh water of Lake Nicaragua and the Rio San Juan was first described (as Eulamia nicaraguensis) by Gill and Bransford (1877). These authors also first proposed the theory that the sharks, as well as the sawfish and tarpon that occur in the lake, were trapped there by late Pleistocene volcanic activity, which isolated a former bay of the Pacific and resulted in the formation of the present lake. The theory of a landlocked, distinct species, of Pacific origin, has en joyed wide popular acceptance and for many years was also accepted by professional …
Calcium And Other Ions In Blood And Skeleton Of Nicaraguan Fresh-Water Shark, Marshall R. Urist
Calcium And Other Ions In Blood And Skeleton Of Nicaraguan Fresh-Water Shark, Marshall R. Urist
Investigations of the Ichthyofauna of Nicaraguan Lakes
The bull shark, Carcharhinus lellcas, employing archaic but effective means of regulating the physical-chemical composition of its body fluids, thrives in tropical fresh-water rivers and lakes. The ionic strength of the serum and the concentrations of total solutes, calcium, urea, and other ions are below the levels found in marine elasmobranchs but higher than the levels in teleosts. The patterns of the calcium deposits of the vertebrae are identical in marine and fresh-water subspecies.
Body Fluid Solutes Of Juveniles And Adults Of The Euryhaline Bull Shark Carcharhinus Leucas From Freshwater And Saline Environments, Thomas B. Thorson, C. Michael Cowan, Donald E. Watson
Body Fluid Solutes Of Juveniles And Adults Of The Euryhaline Bull Shark Carcharhinus Leucas From Freshwater And Saline Environments, Thomas B. Thorson, C. Michael Cowan, Donald E. Watson
Investigations of the Ichthyofauna of Nicaraguan Lakes
Since the discovery of the phenomenally high urea content of the body fluids of cartilaginous fishes by Staedeler and Frerichs (1858), the unique osmoregulatory system of this vertebrate class has been studied by many investigators. In broad outline, the mechanisms are essentially similar in all three of the major subtaxa: the selachians, the batoids, and the holocephalans. A single exception is the genus Potamotrygon (fresh-water stingrays of South America and Africa), which has apparently lost the ability to concentrate urea even when transferred to salt water.
The Rectal Gland In Relation To The Osmoregulatory Mechanisms Of Marine And Freshwater Elasmobranchs, Giuseppe Gerzeli, Gian Franco De Stefano, Lorenzo Bolognani, Kurt W. Koenig, Maria Victoria Gervaso, Maria Fausta Omodeo-Salé
The Rectal Gland In Relation To The Osmoregulatory Mechanisms Of Marine And Freshwater Elasmobranchs, Giuseppe Gerzeli, Gian Franco De Stefano, Lorenzo Bolognani, Kurt W. Koenig, Maria Victoria Gervaso, Maria Fausta Omodeo-Salé
Investigations of the Ichthyofauna of Nicaraguan Lakes
The rectal gland of elasmobranchs secretes large quantities of electrolytes and is of primary importance in the osmoregulatory mechanisms of these animals (Burger and Hess, 1960; Burger, 1962). Analogously, various organs of other vertebrates are also known to be involved in salt secretion (Schmidt-Nielsen, 1965; Bonting, 1970; Bentley, 1971). In general, active ion transport is the basis of this phenomenon; in any case, it requires the presence of structural devices, morphologically and chemically well defined, and of metabolic capabilities which, taken singly, are not specific, but collectively are consistent with active ion transport and salt secretion.
Helminths From Elasmobranchs In Central American Fresh Waters, Donald E. Watson, Thomas B. Thorson
Helminths From Elasmobranchs In Central American Fresh Waters, Donald E. Watson, Thomas B. Thorson
Investigations of the Ichthyofauna of Nicaraguan Lakes
Five species of monogeneans and 14 species of cestodes are reported from two elasmobranch species in fresh waters of Guatemala, Nicaragua and Costa Rica. Monogeneans from the bull shark, Carcharhinus leucas (Muller and Henle, 1841), are: Dermophthirius maccallumi n. sp. (Microbothriidae); Heteronchocotyle leucas Hargis, 1955 and Erpocotyle carcharhini n. sp. (Hexabothriidae). Cestodes from the bull shark are: Phyllobothrium lactuca van Beneden, 1850, P. leuci n. sp., P. nicaraguensis n. sp., Anthobothrium cornucopia van Beneden, 1850, A. laciniatum Linton, 1890 (Phyllobothriidae): Platybothrium hypoprioni Potter, 1937, Phoreiobothrium triloculatum Linton, 1901 (Onchobothriidae); Cathetocephalus thatcheri Dailey and Overstreet, 1973 (Cathetocephalidae); Dasyrhynchus variouncinnatus (Linton, 1924) …
Sexual Dimorphism In Number Of Rostral Teeth Of The Sawfish, Pristis Perotteti Miiller And Henle, 1841, Thomas B. Thorson
Sexual Dimorphism In Number Of Rostral Teeth Of The Sawfish, Pristis Perotteti Miiller And Henle, 1841, Thomas B. Thorson
Investigations of the Ichthyofauna of Nicaraguan Lakes
Rostral tooth counts were made of 211 sawfish (Pristis perotteti) from the Lake Nicaragua-Rio San Juan System. The number of teeth is established early in development and it changes only on accidental loss of teeth, which are not replaced. The average number on the left side is equal to that on the right, but in individuals, either side may have as many as three more teeth than the other. Female tooth counts average 15.94 per side and range from 14 to 18, while males average 18.00 with a range of 16 to 20. Within litters, this dimorphism is …
Columnaris Disease Of Fishes, S. F. Snieszko, G. L. Bullock
Columnaris Disease Of Fishes, S. F. Snieszko, G. L. Bullock
United States Fish and Wildlife: Staff Publications
Columnaris disease is a chronic to acute infection that affects salmonids and many species of warmwater fishes. The first description of the disease was given by Davis (1922) who named the disease and bacterium from the columnar arrangement of cells as seen in wet mounts. The bacterium causing columnaris disease was first isolated by Ordal and Rucker (1944). They identified the organism as belonging to the group known as slime bacteria or myxobacteria; because it produced fruiting bodies and microcysts, they named it Chondrococcus columnaris. Garnjobst (1945), who was unable to find fruiting bodies, renamed it Cytophaga columnaris. …