Ключевые слова: aid, architecture, atlantic, canal, cascade, corridor, counter, ecology, estonia, europe, european, fish, fish farm, fish ladder, fish migration, fishing, help, infrastructure, ladder, migration, migration aid, monitor, monitoring, natural, nature, nature conservation, outdoor, overcoming, pirita, project, rapids, register, registration, reproduction, river, salmon, spawning, stream, tallinn, trout, upstream, water, wild, wildlife,