Transformation empirique des tables numeriques de Galton en tables des probits

Comparison between Galton equation and preston normal logarithms models allowed an empirical reconstitution of probits tables.

The U.S. Gulf of Mexico Party Boat Industry: Activity Centers, Species Targeted, and Fisheries Management Opinions

In addition to providing an overview of the party boat fishery in the U.S. Gulf of Mexico, a management-oriented methodology is presented that can be used elsewhere to assess regulatory impacts. Party boat operators were interviewed to determine species targeted, percent time committed to targeting each species, and opinions on current catch restrictions. Over two-thirds of the fieet was located on the west coast of Florida. Overall, most boats targeted <5 species. Four species accounted for 90 percent of the estimated effort by party boats in the U.S. Gulf of Mexico: Snapper; Lutjanus sp.; grouper, Epinephelus sp. and Mycteroperca sp.; amberjack, Seriola dumerili; and king mackerel, Scomberomorus cavalla. Party boat effort in Texas was devoted primarily to snapper, whereas in Florida most effort was devoted to snapper and grouper collectively. Party boat operators were diverse in their opinions of management regulations in force when interviewed. Results revealed why major opposition would he expected from Texas party boat operators for red snapper bag limits and other restrictions proposed by the Gulf of Mexico Fishery Management Council.

The U.S. Gulf of Mexico Charter Boat Industry: Activity Centers, Species Targeted, and Fisheries Management Opinions

The charter boat industry in U. S. Gulf of Mexico provides access to offshore fishing opportunities for about 570,000 passengers per year on 971 boats. A 25% random sample of charter boat operators was interviewed during 1987-88 to determine species targeted, percent time committed to targeting each species, and reactions to existing catch restrictions. Three-fourths of the charter boat fleet was in Florida, 13% in Texas, 5% in Louisiana, 4% in Alabama, and 2% in Mississippi. Responses were diverse regarding species focus within the region. Species of dominant importance included groupers, Epinephelus sp. and Mycteroperca sp. (Fla.); snapper, Lutjanus campechanus (Ala., Fla., Miss., and La.); king mackerel, Scomberomorus cavalla (Miss., Tex., Ala. and Fla.); spotted seatrout, Cynoscion nebulosus (Tex. and La.); and red drum, Sciaenops ocellatus (Tex. and La). Catch restrictions were generally supported with higher levels of opposition to restricted high effort fish and/or one fish or closed fishery limits.

Coping with the Lionfish Invasion: can targeted removals yield beneficial effects?

Invasive species generate significant environmental and economic costs, with maintenance management constituting a major expenditure. Such costs are generated by invasive Indo-Pacific lionfish (Pterois spp.) that further threaten already stressed coral reefs in the western Atlantic Ocean and Caribbean Sea. This brief review documents rapid range expansion and potential impacts of lionfish. In addition, preliminary experimental data from targeted removals contribute to debates about maintenance management. Removals at sites off Little Cayman Island shifted the size frequency distribution of remaining lionfish toward smaller individuals whose stomachs contained less prey and fewer fish. Fewer lionfish and decreased predation on threatened grouper, herbivores and other economically and ecologically important fishes represent key steps toward protecting reefs. However, complete evaluation of success requires long-term data detailing immigration and recruitment by lionfish, compensatory growth and reproduction of lionfish, reduced direct effects on prey assemblages, and reduced indirect effects mediated by competition for food. Preventing introductions is the best way to avoid impacts from invasive species and early detection linked to rapid response ranks second. Nevertheless, results from this case study suggest that targeted removals represent a viable option for shifting direct impacts of invasive lionfish away from highly vulnerable components of ecosystems.

Final report of the targeted research on Indian mackerel and sharks and national plan of action for conservation and management of shark resources, Thailand

Research included: population structure of Indian mackerel (Rastrelliger kanagurta); a National Plan of Action for the conservation and management of sharks; levels of heavy metals in shark products; and a database on rays.

Policies on poverty and the fisheries sector in Uganda: the current policy trends

There are concerns, at least among the proponents of development, on how to link policy development processes in Uganda and the associated transformation of the poor to high standards of living. In fact some questions have been posed as to whether it's the absence of poverty-targeted policies that a good proportion of individuals or communities are still poor. In the fisheries sector where most of the fish dependent communities live, poverty indications are still prevalent although arguments have been put that current reforms in the sector have transformed the lives of the fish dependent communities. The 1999/2000 household survey report indicates that the poverty levels reduced to 35% of Uganda's total population from 44% in 1997. The question that arose, which still arises anyway, was to define who is actually poor. When measuring poverty one is ultimately interested in the 'standards of living' of individuals especially those, whose standards of living are inadequate. The basic element of measuring this inadequacy/adequacy, at least in Uganda, is to use the household income or consumption per adult equivalent. Studies have demonstrated that household consumption expenditure is a good approximation of household income1. Therefore, for purpose of this report, we define poor households to mean based on that that one adopted by the Ministry of Finance to mean "households whose expenditure per adult equivalent falls below the poverty line 3 ". Many government documents report that the poverty line is one dollar a day. Therefore someone is below the poverty line if he or she lives on less than one dollar a day. In this paper, we analyse the evolution of poverty-driven policies that have been put in place by government and how these policies are shifting or are likely to shift the lives of fish dependent communities. We argue that combinations of poverty-policies are being translated into increased incomes and welfare of most individuals in the fisheries sector. The reasons for this shift, we argue, is as a result of a combination of factors all supported by non other that poverty-led government policies.

The fish stocks in Uganda aquatic systems: opportunities and challenges for transformation

The status of fish stocks in a water body at any one time is a function of several factors affecting the production of fish in that water body. These include: total number (abundance) and biomass(weight) present, growth (size and age), recruitment (the quantity of fish entering the fishery) including reproduction, mortality which is caused by fishing or natural causes, Other indirect factors of major importance to the status of the stocks include production factors (water quality and availability of natural food for fish), the life history parameters of the different species making up the stocks (e.g. sex ratios, condition of the fish, reproductive potential (i.e. fecundity) etc), Changes in fish stocks do occur when any of the above listed factors directly influence aspects of growth, reproduction and mortality and therefore, numbers and standing stock (biomass). In the exploited fisheries, major research concerns regarding stocks relate to the listed factors especially: estimates of stock abundance/biomass, the quantity of fish being caught,where the fish are caught, which species are caught (relative abundance)when the fish are caught, how the fish are caught. The balance between stock abundance and amount of fish caught provides the basis for intervention. Due to the diverse characteristics of the physical water environment, fishes are in general, not evenly distributed throughout a water body. Shallow and vegetated areas tend to support higher abundance and diversity of fish species. In addition, seasonal variations in fish abundance are so strong that fluctuations in catch have to be expected at fish landings.