Small seine net fish assemblages in the headwater region of the Kariega Estuary are described and compared to the catch composition in other parts of the system. The geographical headwaters of the freshwater ‘deprived’ Kariega Estuary were utilised by a range of fish species but, in contrast to the nearby freshwater ‘rich’ Great Fish Estuary, few important angling species (e.g. spotted grunter ...

In Caeté Estuary, the decrease of larval abundance downstream was attributed to reduced retention, since ebb tide densities prevailed mainly in the middle and lower estuary during the rainy season due to increased freshwater outflow. Anchovia clupeoides, Stellifer microps and Guavina guavina were most abundant in the late dry season on flood tides in the upper estuary, whereas ebb tide densitie...

Changes in freshwater inflow can cause changes in the distribution and diversity of marsh vegetation in estuarine habitats. In the fall of 2002 bankside vegetation was surveyed along the 24 km length of the Altamaha River estuary (n= 14 sites). Sites were quantified for multiple plant and edaphic parameters, including plant density, height, and tiller diameter. In this paper we present the char...

To elucidate the fate of river-borne nitrate in the estuarine environment, we measured nitrate concentrations and d15N and d18O of nitrate along the salinity gradient in the estuary of the river Elbe, one of the largest German rivers discharging into the North Sea. Nitrate concentrations in river waters ranged from 78 mmol L21 to 232 mmol L21; d15N varied from 8.2% to 16.2%, and the d18O values...

Water samples from Pahang River estuary were analysed for Cu, Pb, Zn and Cd at 63 stations during the monson and non-monsoon seasons. Concentrations ranges of dissolved metals in the Chukai estuary were relatively low compared with other estuaries and are not significantly influenced by seasonal changes. Concentration of Cu in both monsoons ranged from 0.57 – 1.01 μgl-1, Pb ranged 0.88 – 1.34 μ...

The mortality of salmon smolts during their migration out of freshwater and into the ocean has been difficult to measure. In the Columbia River, which has an extensive network of hydroelectric dams, the decline in abundance of adult salmon returning from the ocean since the late 1970s has been ascribed in large measure to the presence of the dams, although the completion of the hydropower syste...

This paper analyzes downstream effects of freshwater flow diversion from a small, active-continentalmargin river basin. The Skokomish River delta, a tributary estuary to Hood Canal in Washington state, receives drainage from the southeastern side of the Olympic Mountains. Its drainage basin is steep, and rainfall is high. Since completion of two dams in 1930, approximately 40% of the annual ave...

The impact of freshwater discharges from upstream hydroelectric projects on estuarine ecology, particularly on commercial bivalves was seldom ever studied, despite the fact that they contribute substantially to local livelihoods. Such projects have been executed in many rivers of Indian Western Ghats unmindful of their ecological consequences. Through a period of the past five decades, two hydr...

California’s primary hydrologic system, the San Francisco Estuary and its upstream watershed, is vulnerable to the regional hydrologic consequences of projected global climate change. Previous work has shown that a projected warming would result in a reduction of snowpack storage leading to higher winter and lower spring-summer streamflows and increased spring-summer salinities in the estuary. ...