Contributions to the biology of the engraulid Anchoa naso (Gilbert and Pierson, 1898) from Ecuadorian waters

ENGLISH: One phase of the duties of the Inter-American Tropical Tuna Commission is the gathering and interpretation of data concerning the life history of the commercially important bait species throughout the Eastern Pacific Ocean. During 1958 the Commission established a laboratory in Manta, Ecuador to study tuna. It was subsequently found that this fishery was dependent upon one species of anchovy, Anchoa naso, which was locally referred to as "colorado." During the calendar year 1959 approximately 380,000 scoops of bait were taken by the Manta tuna fleet (Schaefer, 1960), which at that time numbered about 23 vessels. Since then the fleet has increased by about 25 per cent and it is probable that the bait catch has increased also. Virtually nothing has been reported concerning the life history of this species. Hildebrand (1943) reviewed its taxonomy and reported standard lengths ranging from 32 to 135 mm. Peterson (1956) examined specimens from Central America and found them to range from 27 to 66 mm. He also indicated that the species spawned over a long period of time. The present report describes some aspects of the life history of Anchoa naso in Ecuadorian waters. The findings are based on 121 collections taken during the period March 1959 through June 1961. SPANISH: Una fase de las obligaciones de La Comisión Interamericana del Atún Tropical es la obtensión e interpretación de los datos concernientes a la historia natural de las especies de carnada comercialmente importantes en todo el Océano Pacifico Oriental. En el año de 1958 la Comisión estableció un laboratorio en Manta, Ecuador, para estudiar el atún. Se encontró subsecuentemente que esta pesquería dependía de una especie de anchoa, Anchoa naso, conocida localmente con el nombre de colorado. Durante el año calendario de 1959, la flota atunera de Manta, que en ese tiempo alcanzaba a unos 23 barcos, obtuvo aproximadamente 380,000 copas (scoops) de carnada (Schaefer, 1960). Desde entonces la flota ha aumentado en un 25 por ciento, y es probable que la captura de peces-cebo haya aumentado también. Nada se ha informado virtualmente sobre la historia natural de esta especie. Hildebrand (1943) revisó su taxonomia e informó sobre su longitud estándar, que varia entre los 32 y 135 mm. Peterson (1956) examinó especímenes de la América Central, y encontró que variaban entre los 27 y 66 mm. También indicó que la especie desova durante un largo periodo de tiempo. El presente informe describe algunos aspectos de la historia natural de la Anchoa naso en aguas ecuatorianas. Los hallazgos están basados en 121 recolecciones hechas durante el periodo de marzo de 1959 a junio de 1961. (PDF contains 30 pages.)

Spawning pattern of the Nematopalaemon hastatus (Crustacea: Palaemonidae) (Aurivilius, 1898), exploited in the artisanal shrimp fishery in the outer Cross River estuary

Some aspects of the reproduction of Nematopalaemon hastatus in the artisanal shrimp fishery in the outer Cross River estuary (Nigeria) was investigated. 2 kg samples were taken from the daily catch of the N. hastatus fishery on a twice-weekly basis. The N. hastatus in the sample were then observed for gravidity, using a hand lens, and their post-orbital carapace length (POCL) taken. This was done over a 12-month period. The eggs in formalin-fixed samples showed colour changes from light orange to dark brown with maturation. Gravid females with eggs in different stages of maturation, from light orange to dark brown were observed in the samples. The reproduction occurs all year-round. The proportion of gravid females observed in samples had two distinct peaks in June and November, and two distinct troughs in May and October. The lowest length at which gravidity was observed was 6.0 mm POCL. There were no Penaeus notialis in the samples

Species of the rougheye rockfish complex: resurrection of Sebastes melanostictus (Matsubara, 1934) and a redescription of Sebastes aleutianus (Jordan and Evermann, 1898)(Teleostei: Scorpaeniformes)

The widespread and commercially important rougheye rockfish, Sebastes aleutianus (Jordan and Evermann, 1898), has been considered a single variable species, with light- and dark-colored forms, found on the outer continental shelf and upper slope of the North Pacific Ocean. Genetic analysis of 124 specimens verified the presence of two species in new specimens collected from Alaska to Oregon, and the two species were analyzed for distinguishing color patterns and morphological characters. Characters distinguishing the two were extended to an analysis of 215 additional formalin-fixed specimens representing their geographic ranges. Sebastes aleutianus is pale, often has dark mottling on the dorsum in diffuse bands, and does not have distinct dark spots on the spinous dorsal fin; it ranges from the eastern Aleutian Islands and southeastern Bering Sea to California. Sebastes melanostictus (Matsubara, 1934), the blackspotted rockfish, ranges from central Japan, through the Aleutian Islands and Bering Sea, to southern California. It is darker overall and spotting is nearly always present on the spinous dorsal fin. Sebastes swifti (Evermann and Goldsborough, 1907) is a synonym of S. aleutianus; S. kawaradae (Matsubara, 1934) is a synonym of S. melanostictus. The subgenus Zalopyr is restricted to S. aleutianus and S. melanostictus. Nomenclatural synonymies, diagnoses, descriptions, and distributions are provided for each species.

Charles Henry Gilbert (1859-1928), Naturalist-in-Charge, and Chauncey Thomas, Jr. (1850-1919), Commanding: Conflict Aboard the U. S. Fish Commission Steamer Albatross in 1902

Charles Henry Gilbert (1859-1928) was a pioneering ichthyologist who made major contributions to the study of fishes of the American West. As chairman of the Department ofZoology at Leland Stanford Junior University in Palo Alto, Calif., during 1891-1925, Gilbert was extremely devoted to his work and showed little patience with those ofa different mindset. While serving as Naturalist-in-Charge of the U.S. Fish Commission Steamer Albatross during her exploratory expedition to the Hawaiian Islands in 1902, Gilbert engaged in an acrimonious feud with the ship's captain, Chauncey Thomas, Jr. (1850-1919), U.S.N., over what Gilbert perceived to be an inadequate effort by the captain. This essay focuses on the conflict between two strong figures, each operatingf rom different world views, and each vying for authority. Despite the difficulties these two men faced, the voyage of the Albatross in 1902 must be considered a success, as reflected by the extensive biological samples collected, the many new species of animals discovered, and the resulting publication of important scientific papers.

Morphometry, length-weight relationship and food and feeding habits of Otolithoides biauritus (Cantor, 1850) of Bombay waters

Thirteen morphometric and seven meristic characters, length-weight relationship and food and feeding habits of Otolithoides biauritus of Bombay coast (Maharashtra, India) were studied. Compared morphometric characters revealed positive allometric growth and high correlation ("r" ranging 0.898 - 0.996) between each other. Meristic characters were observed to be B sub(vii), D sub(1) 8-10, D sub(2) 27-31, P 17-20, V 5-7 and 7-10. Number of gill rackers on the first left gill arch ranged from 15 to 19. Length-weight relationship for both sexes together worked out to be W = 0.026, L super(2.646). The species is a predator, feeding mainly on motile Acetes, small fish and Loligo in order of preference.

Population dynamics and stock assessment of Koth (Otolithoides biauritus Cantor, 1850) along the north-west coast of India

MSY, growth, selection and mortality parameters of Otolithoides biauritus have been worked out from data collected by MFV Saraswati of CIFE, and length frequency data from Ferry Wharf, Sasson dock, and Versova fish landing centres of Bombay. Values of L infinity, K, and t omicron obtained from length frequency study are 1572 mm, 0.2633/yr and 0.0289 yr respectively, and of weight growth parameters are W infinity = 10067 g, K = 0.03904/yr and t omicron = 0.0137 yr. Selection parameters are L + 150 mm, t sub(r) + 0.4167 yr lc + 240 mm and t omicron = 0.6367 yr. Selection factor (K) for codent worked out to be 12. Based on Z = 0.6486, the MSY of O. biauritus off northwest coast of India is assessed as 1,802 tons which is slightly higher than the current catch level of 1,634 tons.

Escala macroscópica de maturaçāo e ciclo sexual das espécies Penaeus indicus H. Milne Edward e Metapenaeus monoceros (Fabricius)

The macroscopic scale used for determination of sexual maturity in shrimps was tested against objective parameters namely the gonad-somatic index and the size of oocytes. The two main species caught in Mozambique, Penaeus indicus and Metapenaeus monoceros, were the object of the work. In order to reduce the subjectivity in the macroscopic exam, a table with the colours representative of each stage is presented. Since this study was conducted over a period of 13 consecutive months and there were observations from previous years, the sexual cycle of the two species is also presented, as well as an estimate of the size at first maturity.

Technical report of frame and catch assessment surveys of Lakes Edward and George; and the Kazinga Channel conducted in January and July 2011- 2013

This study aimed at evaluating the production levels in terms of catch estimates of the artisanal fisheries of the Edward-George system in addition to providing information on the facilities and services at landing sites and the composition, magnitude and distribution of fishing effort to guide development and management of the fisheries resources of the Edward and George lakes and Kazinga channel. Specifically, the study was expected to come up with the following outputs:- a) Information on the number of fish landing sites on the basin lakes; b) Information on the facilities available at the fish landing sites to service the fisheries sector ; c) Information on the number of fishers; d) Information on the number and types of fishing crafts; e) Information on the modes of propulsion of the fishing crafts; f) Information on the number types and sizes of fishing gears including the number of illegal fishing gears in the fishery; and g) Recommendations on development and management of the fisheries of the Edward and George lakes and Kazinga channel. h) Beach values in terms of annual catches and annual revenue from the water bodies.

A baseline survey of water quality, invertebrates, fisheries and socioeconomics on Lake Edward for proposed seismic surveys in block 4B : Final report

The National Fisheries Resources Research Institute (NaFIRRI) on behalf of OPEP Consult Ltd undertook a baseline survey of the transition zone (basically along the shoreline) and near shore habitats of the Uganda apart of Lake Edward and Kazinga channel during December 2007 to January 2008. A major objective of the baseline survey was to generate baseline information on the aquatic ecosystem features related to the fisheries and socio-economics of the fish catch including issues raised by residents in the fish landing sites. Therefore, the baseline survey captured information on water quality, the aquatic invertebrate fauna, aspects of fish biology and ecology, the fish catch including facilities at fish landings, value in the catch and related fisheries socio-economic issues perceived by residents in the settled areas along the shores.

Fishery resources and some economic aspects of four fishing villages on Lakes George and Edward in the Queen Elizabeth National Park, Uganda

The fishery resources of Lake George and Ugandan waters of Lake Edward are described. The main fish species currently observed in the commercial catches were determined and the reasons of changes in species composition of the catches. that occurred in the recent years, are explained. The fishing activity and some economic and nutritional aspects of four fishing villages, selected among the ten present within the Queen Elizabeth National Park boundaries, are analyzed, In the end some suggestions are given for management of the fishery resources of these lakes.

Plankton identified in stomach contents of Oreochromis niloticus (Pisces, Cichlidae) and the water system of Lakes Edward, George, and Kazinga channel - Uganda

The samples were collected from Lake Edward at Rwenshama, Kisenyi and Katwe, and from Lake George at Mahyoro, Kashaka and Kasenyi and in Kazinga Channel at Katunguru. The organisms identified from the water samples obtained irrespective of station or depth were mainly the phytoplankton (diatoms, blue-green algae and green algae). Of the phytoplankton, blue green-algae were the most abundant both in quantity and number of species especially in L. George. In order of importance were Microcystis spp, Planktolyngbya spp and Anabaenopsis spp were the dominant blue greens. Diatoms and green algae were present but less abundant. The estimated proportions of different types of phytoplankton identified in O. niloticus stomach contents indicate that bluegreen algae were the most abundant followed by the diatoms and green algae.