نتایج جستجو برای: caspian whitefish
تعداد نتایج: 4214 فیلتر نتایج به سال:
Recently, several studies indicated that species from the Ponto-Caspian region may be evolutionarily predisposed to become nonindigenous species (NIS); however, origin of NIS established in different regions has rarely been compared to confirm these statements. More importantly, if species from certain area/s are proven to be better colonizers, management strategies to control transport vectors...
We describe here the first fossil otoliths from the Middle Miocene (Badenian and Sarmatian) of Belgrade, Serbia. They were obtained from Lower Badenian outcrops at Slanci and from upper Badenian and Sarmatian sediments recovered from four shallow wells near the village of Barajevo. The otoliths from the Lower Badenian of Slanci represent fishes typical for an open marine environment, characteri...
Understanding drivers of recruitment variation in fish populations requires research conducted on early life stages. Examination otoliths provides useful information for estimating hatching dates, growth, and survival rates larvae investigating the relationship between stage phenology environmental factors such as climate food availability. In Laurentian (i.e., North American) Great Lakes, sign...
A negotiation support system for resolving an international trans-boundary natural resource conflict
Post-Soviet legal governance regime of Caspian Sea e the largest inland body of water on earth e remains a source of conflict among the five coastal states of Azerbaijan, Iran, Kazakhstan, Russia, and Turkmenistan. Although different division methods have been suggested for sharing the sea and its valuable resources, the actual gain of the countries is unclear as the proposed methods focus eith...
Accelerated growth of freshwater fish during anthropogenic eutrophication has been attributed almost exclusively to the increased nutrient content, while density-dependent effects have been largely neglected. We evaluated the relative importance of these factors by studying the growth of 43 consecutive year classes of common whitefish (Coregonus lavaretus) from Upper Lake Constance. This prealp...
INTRODUCTION The sturgeons of the Caspian Sea are considered highly valuable species. The Caspian Sea has traditionally been regarded as the sea of sturgeon since it produces more than 90 percent of the world’s caviar. Despite a remarkable decline of sturgeon numbers over recent years, the Caspian Sea still continues to be of considerable importance in sturgeon fisheries. In 1997, the global la...
This study was designed to test the hypothesis that anadromous populations of North American whitefish, Coregonus clupeuformis (Mitchill), believed to have suffered more intense population bottlenecks during past glaciation events, should reveal less mitochondrial DNA (mtDNA) variability and population-genetic structuring than anadromous populations of European whitefish, C. luvuretus (L.). C. ...
* The author is employed at the United Nations Environment Programme’s Regional Office for Europe. The paper is presented by the author in her personal capacity, however, and opinions expressed in this paper should be attributed to the author. They are not meant to represent the positions or opinions of UNEP or the State Parties to the Framework Convention on the Protection of the Marine Enviro...
Iran’s security is affected by a broad region that includes the Caspian Basin, Central Asia, Afghanistan, the Persian Gulf states, Pakistan, Turkey, and the Middle East. However, an increased focus on the countries of the Economic Cooperation Organization (ECO), as well as Iraq, on the one hand, and with members of the Gulf Cooperation Council (GCC) (including Yemen) on the other, provides a na...
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