Canal diggers in Panama, 1904 to 1928

Leonard Carpenter Panama Canal Collection. Publication: The Canal Diggers in Panama 1904 to 1928 [Box 1] from the Special Collections & Area Studies Department, George A. Smathers Libraries, University of Florida. (10 page document)

Pulling net in Lune Estuary 1949

Two fishermen pulling a net in a boat in Lune Estuary, North West England, UK. This photo is part of a Photo Album that includes pictures from 1935 to 1954.

River Lune Pollution at Lancaster in July 1949

Houses close to River Lune at Lancaster, North West England, UK. This photo shows the polluted River Lune in July 1949. This photo is part of a Photo Album that includes pictures from 1935 to 1954.

River Lune the Baulk, Cockersand Abbey Lighthouse 1949

Cockersand Abbey Lighthouse, in River Lune the Baulk, River Lune estuary on the Lancashire Fylde peninsula in the North West of England, UK. This photo is part of a Photo Album that includes pictures from 1935 to 1954.

Abbeystead Fish Pass in the River Wyre, 1949

Photo of a check trap in Abbeystead Fish Pass in the River Wyre in 1949. The River Wyre is located in the North West of England, UK. This photo is part of a Photo Album that includes pictures from 1935 to 1954.

River Clough Farfield Weir showing a gap made for migratory fish June 1949 (Lune)

River Clough Farfield Weir showing a gap made for migratory fish in June 1949 (Lune). This photo is part of a Photo Album that includes pictures from 1935 to 1954. This Album was held by the EA North West.

Churchtown Weir in the River Wyre May 1949

ChurchTown Weir in the River Wyre, North West of England, UK. This photo is part of a Photo Album that includes pictures from 1935 to 1954.

Relationships between ENSO events and San Francisco rainfall, 1949-1991

As California entered its sixth consecutive year of drought, the onset of a positive sea surface temperature anomaly in the equatorial Pacific and other indicators of a developing ENSO event were observed. This brought the following question from the media, water officials, and the public: What effect will El Niño have on the current rainfall season in general and on the intraseasonal distribution of rain in particular? To answer the question, the historical San Francisco rainfall record was examined in relationship to previous ENSO events.

Wadge Bank trawl fishery studies. Pt. 4. An analysis of the length frequency measurements of the sea bream (Lethrinus nebulosus) made in 1949 and 1953 to 1958

Length frequency distributions of the sea bream collected during the period 1953 to 1958 have been analysed. The increase in average sizes of the sea bream with depth suggests a movement to deeper waters with increase in size. By numbers, the sea bream is more abundant between 21 and 30 fathoms than in deeper areas. The recruitment was continuous and regular. There is no sign of entry or progression of a dominant brood throughout the period under study. Length frequency distribution shows three distinct modes. The first mode occurs regularly but does not progress beyond 40cm, recruitment being balanced by natural and fishing mortality. The other two which are not regular are probably the result of fishing outside regular areas. Short sections of “growth” lines which fit into one another when extrapolated, are evident. The larger lines obtained by extrapolation are parallel to one another. These tentative "growth lines" indicate that this species which enters the fishing grounds, when 15 cm or larger in length are exploited by the trawl fishery for a period of three to four years. This species appears to be six months old when it enters the fishing grounds and increases in length by about 37.5 cm in the next 30 months. Later growth slows down. The average size of the specimens sampled continued to get smaller from 1953 till 1957. It is shown that this reduction in size is due to increased fishing effort.

East African Inland Fisheries Research Organization Annual Report for year ended 31st December 1949

The present work is now concentrated mainly on the Tilapia fishery. As a result of past experience it is easier to direct efforts in a way likely to give useful results. Work on the Tilapia is now beyond the purely exploratory stage and these fishing experiments are being carried but in areas which are known to contain large numbers of Tilapia. Nets of different mesh size are being used in order to catch all stages of these fish. These nets are being fished at the surface and at the bottom, close to the shore and further out. The data collected should provide more precise information regarding the periodic migration, both vertical and horizontal, of these fish, a better understanding of their life history and breeding habits, and indicate' the potential possibilities of this fishery. These data should explain the variation in numbers of fish caught by Africans during different months of the year; they should also make it possible to determine more exactly the best type of net for use in this particular fishery.

A record of Probopyrus bithynis (Richardson, 1904) in Macrobrachium rosenbergii (De Man) from coastal Andhra Pradesh, India, with special reference to host-parasite relationship

An incidence of bopyrid isopod infestation was observed in giant freshwater prawn, Macrobrachium rosenbergii (de Man) juveniles (40-60 mm/0.9-1.5 g) in a scampi culture farm in East Godavari district of Andhra Pradesh. The presence of parasite was observed by conspicuous boil like swelling of the branchial chamber where the parasite was found lodged on the gills. The infested gill was highly compressed and necrosed. Only one branchial chamber was infested by the parasite while the other gill was normal. The infested prawns were thin and emaciated and showed retarded growth. The parasite was identified as Probopyrus bithynis (Richardson, 1904) which caused inhibition of ventilation due to its permanent lodging in the branchial chamber and impaired the gaseous exchange by gills. It was also observed that this parasite caused parasitic castration in the infested prawns.

Morphometrics, length-weight relationship and condition of Rastrineobola argentea (Pellegrin 1904) in the Winam Gulf of Lake Victoria (Kenya)

Correlation between total length (TL), fork length (FL) and standard length (SL) of Raslrineobola argentea (pellegrin 1904) in the Winam Gulf of Lake Victoria indicate that FL = 0.92 TL - 0.74 and SL = 0.90 TL - 1.74. Length-weight relationship of log-transformed data shows that the slopes of the regression lines were 3.06 to 3.22 for juveniles, 2.70 to 3.05 for males and 3.24 to 3.71 for females. The slopes were significantly different between groups at at a =0.05. The Fulton's condition factor (K) was highest in December (1.019-1.073) and March/April (1.015-1.030) but lowest in June (1:00-1.025) for all stations. Significant differences between groups demands for the use of different growth models for juveniles, males and females especially for the von Bertalanffy growth equation which uses length-weight relationship. Observed cyclic viations in condition factor suggests two peak breeding seasons for this species in the Winam Gulf. The practical lmplications of these results in stock assessment using length-based fish stock assessment methods is briefly discussed.