Effects of environmental deterioration on Northeast Anatolia Trout (Salmo spp.) Populations

In this study, the possible effects of overfishing pressure on local Salmonid populations and the critical environmental changes that have occurred in the wild habitats that have been deteriorating since the beginning of the 21st century were investigated in Northeast Anatolia. In the research, methods including quantitative and qualitative impact assessments were used to determine environmental changes and anthropogenic effects. In addition to numerical data, observations of the stream and its surroundings were recorded. As a result, it has been determined that the natural trout populations, distributed in the limited habitats in the middle and upper parts of the studied rivers, have decreased considerably, especially since the number of individuals who have reached breeding age has reduced to a high level. It has been determined that the habitats in localities where the research was conducted have been under great pressure, since the end of the 20th century, due to infrastructure works, urbanization, and illegal fishing. It has been determined that the local trout populations, distributed in the limited habitats in the middle and upper basins of the studied rivers, are quite damaged. The number of individuals that have reached the breeding age has decreased significantly.