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Landing Site (landing + site)
Selected AbstractsFactors influencing fish catch levels on Kenya's coral reefsFISHERIES MANAGEMENT & ECOLOGY, Issue 4 2007S. C. Mangi Abstract, The factors influencing fish catches on Kenya's coral reefs were studied. Catch data were collected at the species level by counting the number of fish landed at each landing site of each fishing ground. Live coral cover, topographic complexity, fish and sea urchin density, and the number of fishers and gear units used in each fishing ground were compared with catch data. Fishing grounds included one location where only basket traps were allowed, six locations where all gear types were used except beach seines, and three locations where all types of gear, including beach seines, were used. Catch and effort variables were similar across the fishing grounds whereas live coral cover and sea urchin density differed (P < 0.01). The sites fished by all types of gear including beach seines had the lowest coral cover (8.4 ± 0.9%) and topographic complexity (1.12 ± 0.01). Catch levels were positively correlated with the number of fishers and fish density but not with the number of gear units deployed or sea urchin density. The number of fishers and live coral cover were the strongest factors determining total catch levels. The results suggest that high levels of fishing effort coupled with the use of destructive gear types, exacerbate the effects of overfishing on Kenya's reefs. [source] The effect of a closed area and beach seine exclusion on coral reef fish catchesFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2001T. R. McClanahan Fish landing data from the Mombasa Marine National Park (MNP) and a marine reserve exploited by various gears were studied over a 5-yr period to determine the influence of the closed area and different gears in fisheries. The number fishing and boats per landing site was constant, but total and catch per unit effort progressively declined in all sites on an annual basis irrespective of the existence of a marine reserve, exclusion of the beach seines or use of gear. Differences between landing sites were most pronounced when analysed on a catch per area as opposed to the more standard catch per fisherman, suggesting compensation in human effort when catches decline. A marine reserve next to a closed area that excluded beach seines had the highest catch per area (5.5 kg ha,1 month,1) despite having the highest density of fishermen (0.07 ± 0.02 fishermen ha,1 month,1). The annual rate of decline in the catch was lower than the other sites at around 250 g day,1 compared with 310,400 g day,1 in the other sites. One landing site, which excluded beach seine landings for more than 20 yrs, had a high catch per area (,5.3 kg ha,1 month,1), but after experiencing a doubling in the effort of other gears (line, speargun and trap), the catch per fisherman and area were reduced. Environmental or habitat degradation and excessive effort remain the most likely explanation for the overall declines in catch from 1995 to 1999. Closed areas and beach seine exclusion have the potential to increase catch rates, but the first often reduces the total fishing area and possibly leads to a loss of total catch, at least on a time scale of less than 10 yrs. The exclusion of beach seines can lead to an increase in other gear types that can also cause reductions in catch. [source] Reproductive biology and population variables of the Brazilian sharpnose shark Rhizoprionodon lalandii (Müller & Henle, 1839) captured in coastal waters of south-eastern BrazilJOURNAL OF FISH BIOLOGY, Issue 3 2008A. C. Andrade Throughout 1 year, from October 2003 to September 2004, 88 visits to the landing site of a small urban fishery (APREBAN) in Rio de Janeiro city were conducted and 816 specimens of Rhizoprionodon lalandii were analysed. The sample, mostly females, was composed of two cohorts: young-of-the-year were abundant in spring and summer and adults predominated in autumn and winter. Gravid females were most abundant from April to June, whereas post-partum females composed most of the catch in August to September. Adult males were present all year although were more abundant between February and July. No neonates were captured during the study and most embryos collected measured slightly below the reported total length (LT) at time of birth (L0) for the species, suggesting that parturition may occur slightly outside the main fishing grounds or that neonates were not captured in commercial gillnets set at this time of the year. The mean LT at maturity (LT50) for males was 578 mm and females matured between 620 and 660 mm, although a precise estimate of LT50 for females could not be determined. The total length (LT) and total mass (MT) relationship was calculated for both sexes and showed no significant differences. The mean condition factor increased steadily from February to July followed by a steep decrease in values relative to females in August and September, suggesting a pupping season. The present study area can be classified as a coastal juvenile habitat and a probable mating ground for R. lalandii. [source] The effect of a closed area and beach seine exclusion on coral reef fish catchesFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2001T. R. McClanahan Fish landing data from the Mombasa Marine National Park (MNP) and a marine reserve exploited by various gears were studied over a 5-yr period to determine the influence of the closed area and different gears in fisheries. The number fishing and boats per landing site was constant, but total and catch per unit effort progressively declined in all sites on an annual basis irrespective of the existence of a marine reserve, exclusion of the beach seines or use of gear. Differences between landing sites were most pronounced when analysed on a catch per area as opposed to the more standard catch per fisherman, suggesting compensation in human effort when catches decline. A marine reserve next to a closed area that excluded beach seines had the highest catch per area (5.5 kg ha,1 month,1) despite having the highest density of fishermen (0.07 ± 0.02 fishermen ha,1 month,1). The annual rate of decline in the catch was lower than the other sites at around 250 g day,1 compared with 310,400 g day,1 in the other sites. One landing site, which excluded beach seine landings for more than 20 yrs, had a high catch per area (,5.3 kg ha,1 month,1), but after experiencing a doubling in the effort of other gears (line, speargun and trap), the catch per fisherman and area were reduced. Environmental or habitat degradation and excessive effort remain the most likely explanation for the overall declines in catch from 1995 to 1999. Closed areas and beach seine exclusion have the potential to increase catch rates, but the first often reduces the total fishing area and possibly leads to a loss of total catch, at least on a time scale of less than 10 yrs. The exclusion of beach seines can lead to an increase in other gear types that can also cause reductions in catch. [source] A petrological, mineralogical, and chemical analysis of the lunar mare basalt meteorite LaPaz Icefield 02205, 02224, and 02226METEORITICS & PLANETARY SCIENCE, Issue 7 2006Katherine H. Joy They consist mainly of zoned pyroxene and plagioclase grains, with minor ilmenite, spinel, and mesostasis regions. Large, possibly xenocrystic, forsteritic olivine grains (<3% by mode) contain small trapped multiphase melt inclusions. Accessory mineral and mesostasis composition shows that the samples have experienced residual melt crystallization with silica oversaturation and late-stage liquid immiscibility. Our section of LAP 02224 has a vesicular fusion crust, implying that it was at one time located sufficiently close to the lunar surface environment to have accumulated solar-wind-implanted gases. The stones have a comparable major element composition and petrography to low-Ti, low-Al basalts collected at the Apollos 12 and 15 landing sites. However, the LAP stones also have an enriched REE bulk composition and are more ferroan (Mg numbers in the range of 31 to 35) than similar Apollo samples, suggesting that they represent members of a previously unsampled fractionated mare basalt suite that crystallized from a relatively evolved lunar melt. [source] Falkland Islands cruise ship tourism: an overview of the 1999,2000 season and the way forwardAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 1 2002Rebecca J. Ingham Abstract 1.Falkland Islands' tourism is evolving at an increasing pace. A record number of passengers, 23 497, visited the Islands during the 1999,2000 season. This rise was due to an increase in both the frequency of vessel visits and the average passenger capacity of vessels, with the number of luxury cruise ships of >1000 passengers steadily increasing. The Falklands' industry is made up of three types of vessel: the expedition cruise vessels (ca. 100,200 passengers); larger cruise vessels (ca. 400 passengers), and the luxury cruise vessels (ca. 1000 passengers). 2.The cruise ship industry has seen a diversification within the market, with cruises now available to a wider audience thus increasing the need for new experiences and landing sites. A similar diversification is being seen within the Islands themselves as the capacity to take larger vessels at remote sites is being developed. Whilst the expedition cruise vessels visiting the Islands are operating to high environmental standards as members of the International Association of Antarctic Tour Operators (IAATO), vessels with 400+ passengers may not become members of IAATO, due to Article III of the organization's Bylaws which limits the number of passengers. These larger capacity vessels are therefore not subject to the same self-regulating guidelines. The implications of increasing passenger numbers in the islands are discussed with regard to pressures on both the wildlife and vegetation. 3.This study outlines the need for an island-wide approach and a legislative framework to ensure high standards of operation are adhered to within the Islands from all visiting vessels and that accurate information is provided to all visitors along with a suitable code of conduct. The collection, collation and analysis of visitor data to identify trends and implement appropriate management strategies, and further research into the potential impacts of tourism on wildlife in the Falklands are also recommended. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||