Background paper on the international seafood trade and poverty

(121 p.)

Lithology and palynology of cave floor sediment cores from Wakulla Spring, Wakulla County, Florida

Five short bottom sediment cores taken in Wakulla Spring Wakulla County, Florida, were described lithologically and sampled for palynological study. Four of the cores were recoveredfrom sediments at the spring cave entrance (130 feet water depth). One core was taken in a fossil vertebrate bone bed, 280 feet distance into the main spring cave at a water depth of 240 feet. Sediments in the cores are composed of alternating intervals of quartz sand and calcilitite, containing freshwater diatoms, freshwater mollusk shells and plant remains. The predominant pollen present in all cores consists of a periporate variety typical of the herb families Chenopodiaceae and Amaranthaceae. Arboreal flora, typical of the area surrounding the spring today, represent a very low percentage of thle pollen assemblage in the cores. Clustered Chenopod-Amaranth type pollen observed in one core suggest minimal transport prior to deposition, and indicate that the bottom sediments in the cave may be essentially In situ. An absence of exotic flora suggests a Quaternary age for the sediments. (PDF contains 11 pages.)

Keine überdurchschnittlichen Nachwuchsjahrgänge bei den Nutzfischen der Nordsee

In January/February 2001, Germany participated with “Walther Herwig III” in the International Bottom Trawl Survey (IBTS) of ICES by contributing 70 half hour tows with the Grande Ouverture Verticale Bottom Trawl (GOV), 78 hydrographic stations, and 88 catches with the Method-Isaac-Kidd net (MIK), mostly in the central and northern North Sea. In total, 368 fishing stations by means of the GOV were covered by the international fleet. Preliminary results indicate that only indices for herring, whiting, and – to some degree – haddock are in the long-term mean. In contrast, the index for cod gives reason to serious concern. In addition, indices for both mackerel and Norway pout do not show any signs for an increasing strength of these stocks. Oceanographic data show that in comparison with the data from 1995 onwards actual temperatures and salinities are in the normal range. However, mean water temperatures of this short period are about more than a half degree above the long-term means of the period 1961 to 1990.

Mehr Nachwuchs bei Nutzfischarten der Nordsee, ausser beim Kabeljau

Ninety-one half-hour tows with the Grande Ouverture Verticale bottom trawl (GOV), 111 hydrographic stations and 100 catches with the Methot-Isaac-Kidd Net (MIK) were this years’ contribution of “Walther Herwig III” to the IBTS in various areas of the North Sea. Preliminary results indicate that especially haddock and, to some extent, whiting and Norway pout generated an ample 1999 yearclass. Indices for herring are also well above last years’ index whereas the cod indices indicate no substantial improvement of the stock. Largest concentrations of herring larvae were found in Moray Firth and west of the Dogger Bank/The Gut area. Temperatures of the North Sea were found to be above the long term means: 1 Centigrade on the open sea and up to 3 Centigrades in coastal areas. This years’ “WH III” IBTS activities at sea were considerably hampered by rough weather

Life cycle and biological parameters of several Brazilian Amazon fish species

This contribution summarizes knowledge on the biology (population dynamics, reproduction, ecology) of 25 fish species from the Lower Amazon, Brazil, based on data from a Brazilian-German field project (IARA) and a review of the literature.

Comparison of benthic fauna of two beels under different management system

A comparative study of benthic fauna between Rajdhala beel and Padmai beel of Netrakona District under different management system was carried out from July 1999 to January 20OO. An average number of 1113 and 1175 organisms/m2 were obtained from Rajdhala heel and Padmai beel respectively. A total of 22 taxa belonging to 8 diverse groups, Oligochaetes, Chironomids, Molluscs, Ceratopogonids, Diptera (other than Chironomids and Ceratopogonids), Ephemeroptera, Leeches and Crustaceans were recorded. Oligochaetes were dominated and constituted 46% and 49% ofthe total benthic population in Rajdhala heel and Padmai beel respectively. The next dominant group was the Chironomids, which constituted 31% and 30% of the total benthic population in Rajdhala beel and Padmai beel respectively. The highest number 1279 and 1437 individuals/m2 of benthic fauna was recorded in December from Rajdhla beel and Padmai bee! in respectively. The lowest number of benthic fauna 869 and 914 individuals/m2 were found during September and July from Rajdhala beel and Padmai beel respectively. Monthly variation of benthic fauna among two beels were found statistically significant (p<0.05). The numerical distributions of benthic fauna was found to be varied with depth ranges. However, the depth wise variation of total benthic fauna between two heels was not found statistically significant. Fish yield of Rajdhala beel (488 kg/ha/yr) was appreciably higher than the Padmai beel (250 kg/ha/yr).