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Amvrakikos Gulf (Amvrakiko + gulf)
Selected AbstractsTemporal Variations of Nutrients, Chlorophyll a and Particulate Matter in Three Coastal Lagoons of Amvrakikos Gulf (Ionian Sea, Greece)MARINE ECOLOGY, Issue 3 2001Konstantinos A. Kormas Abstract. The temporal variations of nutrients, chlorophyll a (chl a), suspended particulate matter (SPM) and particulate organic carbon (POC) were measured over 12 months in three shallow coastal brackish water lagoons of the Amvrakikos Gulf, Ionian Sea. Two of the lagoons, Tsoukalio and Rodia, are interconnected but separated from Logarou by a narrow strip of land. Logarou has a better water exchange with the sea as indicated by the higher salinity and dissolved oxygen concentrations and the smaller variation of the above-mentioned parameters. Nitrate concentrations were largely the same in the three lagoons and higher than in the Amvrakikos Gulf. Phosphate concentrations in Logarou exceeded by far those of Tsoukalio/Rodia; the increased phosphate levels recorded in January caused an extended phytoplankton bloom with chl a concentrations higher than in the other two lagoons. Chl a in Tsoukalio was positively correlated with nitrate whereas in the most shallow lagoon, Logarou, it showed a positive correlation with light winds (force 4 and lower), probably caused by resuspension from the sediment. Increased phytoplankton biomass in Logarou coupled with the better water exchange may be related to the higher fish production in this lagoon. [source] Dolphins in a bottle: abundance, residency patterns and conservation of bottlenose dolphins Tursiops truncatus in the semi-closed eutrophic Amvrakikos Gulf, GreeceAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2008Giovanni Bearzi Abstract 1.Boat surveys were conducted between 2002 and 2005 to study bottlenose dolphins living in the 400 km2 Amvrakikos Gulf, western Greece. During 116 survey days, 4705 km of total effort resulted in the individual photo-identification of 106 animals, through long-term natural markings on their dorsal fins. 2.Mark,recapture analyses based on the Mth model provided estimates of 82 marked individuals in 2003 (95% CI=80,91), 92 in 2004 (95% CI=86,108) and 98 in 2005 (95% CI=94,110). To include the unmarked portion of the population, the proportion of unmarked individuals was computed based on the number of photographs of marked and unmarked dorsal fins. The mean proportion of unmarked animals in the population was 0.338 (95% CI=0.288,0.389). By adding this to the estimate for marked animals in 2005, considered as the most robust, a total population estimate of 148 individuals (95% CI=132,180) was obtained. 3.Dolphin encounter rates in 2003,2005 did not show significant variations, and averaged 7.2 groups per 100 km or 72.5 individuals per 100 km. Encounter rates within the Gulf were about one order of magnitude greater than those found for bottlenose dolphins in nearby eastern Ionian Sea coastal waters. 4.Mean dolphin density in the Gulf was 0.37 animals km,2. This relatively high density, together with high levels of site fidelity shown by most individuals, was thought to be related primarily to prey availability, particularly of epipelagic schooling fish. 5.The importance of the semi-closed Amvrakikos Gulf for bottlenose dolphins and other threatened species encourages the adoption of measures aimed to conserve its valuable ecosystems and raise the naturalistic profile of the area, while promoting environment-conscious development. Meaningful action includes restoring natural hydrology (e.g. freshwater input from rivers), curtailing pollution from various sources, responsible fisheries and aquaculture management, and control of illegal fishing. Interactions between dolphins and fisheries also deserve careful quantitative investigation. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||