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Ec76-1741 Christmas Trees: A Management Guide, Donald E. Janssen, Neal E. Jennings

University of Nebraska-Lincoln Extension: Historical Materials

In America the decorated Christmas tree has become an accepted tradition. Christmas would seem barren to most people without it. Raising Christmas trees is a growing industry and has proven to be a profitable use of land if high-quality, salable trees are produced.

Planting, managing, and harvesting Christmas trees is a high labor, high risk endeavor. Here is a list of questions. If you can answer "yes" to every one, you will be a successful Christmas tree grower.

Are you willing to plant trees every April?

Are you willing to shear or prune every tree, every year (mid-June to mid-July) …

Heg76-42 Wool And Wool Blends (Revised January 1985), Rose Marie Tondl

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide contains information about buying and sewing wool and wool blends.

Wool is a unique fiber. It is a natural fiber made from the fleece of sheep. Wool fabrics are not all alike. They come in a variety of textures and weights. Wool can be sheer, thin, soft, thick, stiff or anything in between. Wool fabrics are constructed by weaving, knitting or felting.

Some Remarks On The Fecundity Of Tilapia (T. Mossambica Peters) And Its Introduction Into Middle Central America (Nicaragua) Together With A First Contribution Towards The Limnology Of Nicaragua, Dietmar Riedel

Investigations of the Ichthyofauna of Nicaraguan Lakes

a. This paper presents an account of fecundity studies into T. mossambica under Middle Central American conditions and limnological investigations into Lake Moyua/Nicaragua which have been performed during 1961/62.

b. Data obtained as to fecundity of T. mossambica are discussed in the light of the term prolificy and with regard to ecological and biological characteristics of Nicaraguan waters and native fish fauna.

c. A more detailed contemplation about the possible effects of a spread out or transplantation of T. mossambica into other Nicaraguan waters concludes the paper.

Ichthyology Of The Lakes Of Nicaragua: Historical Perspective, Jaime Villa

Investigations of the Ichthyofauna of Nicaraguan Lakes

Scientific study of Nicaraguan freshwater fishes did not begin until Gunther described the first species from Lake Nicaragua in 1864, but actual accounts of several interesting fishes were written as early as the sixteenth century by the first historians of the New World. These accounts ranged from hearsay to rather detailed (for their time) descriptions and first-hand observations on the form and life of some species. In some cases these observations or conclusions have been doubted for many decades but confirmed and elaborated in recent years. Therefore I believe it may be of interest to examine the early chronicles.

Derivation Of The Freshwater Fish Fauna Of Central America, George S. Myers

Investigations of the Ichthyofauna of Nicaraguan Lakes

The nature, composition, and evolution of Centra) American freshwater fish groups are discussed in relation to the history and derivation of the faunal elements. It is concluded that the entire area between the Isthmus of Tehuantepec and eastern Panama was and always had been devoid of primary (obligatory) freshwater fishes prior to the very late Tertiary. Instead, secondary freshwater fishes evolved in this area during the Neogene and perhaps for a longer period, the Poeciliidae having probably had a longer history within the area than the Cichlidae. In the late Tertiary a very few North American immigrants entered the area …

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

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 …

Una Teoría Sobre El Origen De Los Peces De Xiloà, Jaime Villa

Investigations of the Ichthyofauna of Nicaraguan Lakes

A finales de 1965 v en conexion con estudios en curso sobre la herpetolog( a nicaragiiense colec te una pequena serie de peces de la Laguna de Xiloa que revelaron aspectos interesantes y me indujeron a realizar colecciones extensivas en toda la laguna; estas colecciones se realizaron durante 1966-68 y cons tan de varios cientos de ejemplares, depositados en la Universidad de Costa Rica y en mi coleccion particular. El material acumulado durante estos anos y las notas tomadas durante todo el tiempo en que se realizaron han sido suficientes para permitir una serie de conclusiones en diversos aspectos, algunas …

Some Speculations About "The Great Nicaraguan Lake", Jaime Villa

Investigations of the Ichthyofauna of Nicaraguan Lakes

The available evidence indicates that Lakes Managua and Nicaragua were broadly connected in the past, when most of the fish species invaded the "Great Nicaraguan Lake". Due to the lowering of the water level (caused perhaps by tectonic movements and/or erosion produced by the Rio San Juan), Lake Managua became separated from Lake Nicaragua in the Tipitapa area. Water movement from Lake Managua is achieved mostly by seepage through a porous dropoff which prevents the exchange of fishes between the lakes. At about the same time, if not earler, Lake Xilml also became separated. After the more or less permanent …

Peces De La Cuenca De Los Grandes Lagos De Nicaragua, Ignacio Astorqui

Investigations of the Ichthyofauna of Nicaraguan Lakes

El presente trabajo se basa en una coleccion de peces hecha en Nicaragua par el Profesor Luis R. Rivas y el autor des de el 11 de Junia hasta el 14 de Julio de 1960. El trabajo se limita a la cuenca de los Grandes Lagos y rios trio butarios (Fig. 1). La mayor parte del material procede de esta zona y no pre· ten de ser un trabajo ictio16gico definitivo acerca de Nicaragua.
Aspectos de la paleografia de Centroamerica, el origen de la fauna de los lagos y la historia de la ictiologia de Nicaragua se encuentran en un …

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 …

Informe Sobre Los Resultados Del Programa De Investigacion De Los Recursos Pesqueros Del Lago De Nicaragua, Instituto De Fomento Nacional

Investigations of the Ichthyofauna of Nicaraguan Lakes

E1 Instituto de Fomento Nacional (INFONAC), basado en los principios de su Ley Creadora y en la politica de desarrollo pesquero que se ha trazado, tome en el mes de Enero de 1971, la firme determinacion de iniciar el "Programa de Investigacion de los Recursos Pesqueros del Lago de Nicaragua" con una duracion estimada de tres (3) aiios, teniendo como base de operaciones la Ciudad de Granada.

An Investigation Into The Use Of Artificial Habitats As A Means Of Increasing The Fishery Productivity Of The Great Lakes Complex Of Nicaragua, Terrance M. Lim, Kenneth R. Mckaye, Douglas J. Weiland

Investigations of the Ichthyofauna of Nicaraguan Lakes

Protein deficiency is a major dietary problem in Central America where protein-rich foods are scarce and costly. Fish, however, represents a rich source of animal protein that is not being utilized to a significant extent. Moreover, it is a source that could be made available to large portions of the populations of these countries if improvements of the present fishing and distribution methods were realized. Prerequisite to expansion, however, is a basic understanding of the ecosystems and their components. It is at this preliminary stage that the situation presently lies. Once this understanding has been achieved, means of maximizing production …

Length/Weight Frequencies For Five Species Of Fish In Lake Nicaragua, Richard J. Beatty, Kurt W. Koenig

Investigations of the Ichthyofauna of Nicaraguan Lakes

This paper places on record data on the length/weight frequencies of five commercially important species in Lake Nicaragua: Megalops atlanticus, Centropomus parallelus, Lepisosteus tropicus, Cichlasoma citrinellum and Cichlasoma nuaraguense.
The data were collected between November, 1971 and June, 1972, during a preliminary study of the fishery of Lake Nicaragua. The program was sponsored by the Instituto de Fomento Nacional (INFONAC) of Nicaragua, with financial and technical assistance provided by the United Nations Food and Agricultural Organization (FAO) and the United States Peace Corps.

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

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

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 …

Systematic Status Of The Cichlid Fishes Cichlasoma Dorsatum, C. Granadense And C. Nigritum Meek, Jaime Villa

Investigations of the Ichthyofauna of Nicaraguan Lakes

In his Synopsis of the Fishes of the Great Lakes of Nicaragua, Meek (1907) described 3 new cichlid fishes, Cichlasoma dorsatum, C. granadense and C. nigritum. The descriptions appeared after the two major revisions of the genus Cichlasoma (Pellegrin, 1904; Regan, 1905), which perhaps explains why they have since been ignored.

Variación, Coloración Y Estado Sistemático Del Pez Centroamericano Cichlasoma Nicaraguense (Familia Cichlidae), Myrna I. López

Investigations of the Ichthyofauna of Nicaraguan Lakes

Cichlasoma balteatum and C. spilotum are placed in the synonymy of C. nicaraguense on the basis of a review of the literature and examination of fresh material from Lake Nicaragua and the Atlantic slope of Costa Rica. Observations on coloration and caudal fin scalation are included.

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 …

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 …

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 Status Of The Freshwater Shark Of Lake Nicaragua, Thomas B. Thorson, Donald E. Watson, C. Michael Cowan

Investigations of the Ichthyofauna of Nicaraguan Lakes

Nineteen sharks collected from freshwater at several points on Lake Nicaragua and the Rio San Juan were all of the same species and indistinguishable from marine Carcharhinus leucas of the Atlantic. Minor differences previously thought to separate C. leucas from the lake shark proved to be invalid. Females had slightly longer gill slits, somewhat greater breadth of pelvic fin, and a longer abdominal region than males. Clasper length indicated that the onset of sexual maturity in males occurs when they are between 1,600 and 1,700 mm in total length.
The classical theory or origin of the sharks from Pacific ancestry …

An Investigation Of The Feeding Habits Of The Bull Shark, Carcharhinus Leucas, In The Lake Nicaragua-Rio San Juan System, Robert E. Tuma

Investigations of the Ichthyofauna of Nicaraguan Lakes

The bull shark or cub shark, Carcharhinus leucas, occurs in tropical and subtropical waters of the Atlantic, Pacific, and Indian oceans. In the western Atlantic it occurs from New York to southern Brazil.

Partitioning Of Body Fluids In The Lake Nicaragua Shark And Three Marine Sharks, Thomas B. Thorson

Investigations of the Ichthyofauna of Nicaraguan Lakes

The relative volumes of major body fluids of freshwater and marine sharks are remarkably similar in spite of the differences in external medium and in osmotic pressure of body fluids. The small differences detected are in agreement with differences reported in comparisons of freshwater and marine te1eosts: a slightly higher total water content and a smaller ratio of extracellular to intracellular fluids in freshwater forms.

Serum Protein Variation In The Bull Shark, Carcharhinus Leucas Müller And Henle, 1841, C. Michael Cowan

Investigations of the Ichthyofauna of Nicaraguan Lakes

I. A detailed electrophoretic study was made of different developmental stages of the bull shark, Carcharhinus leucas Mülller and Henle, 1841.
2. Both qualitative and quantitative variations were found to exist between newborn and adult bull sharks.
3. Variations in the globulin portion may be related to the development of immunoglobulins.

Comparison Of Some Parameters Of Serum And Uterine Fluid Of Pregnant, Viviparous Sharks (Carcharhinus Leucas) And Serum Of Their Near-Term Young, Thomas B. Thorson, Jeffrey W. Gerst

Investigations of the Ichthyofauna of Nicaraguan Lakes

I. In eight females, serum urea concentrations of 134-336 mM/l. were interpreted as indications of previous environmental salinities.
2. Fetal serum solute concentrations usually resembled those of the mother, but in two cases where fetal urea was higher, it was interpreted as a lag in urea reduction following movement from salt to fresh water.
3. Uterine fluid was similar to maternal serum in all parameters except for its very low protein content.
4. No flushing of the uteri with environmental water occurs.
5. Independent osmoregulation apparently does not occur before birth, although required mechanisms may be present.
6. The full …

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.

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 …

Index Of Scientific Names

Investigations of the Ichthyofauna of Nicaraguan Lakes

Index of scientific names in Investigations of the Ichthyofauna of Nicaraguan Lakes.