Danube bleak
... that the Danube bleak, a migratory fish, has had its traditional routes blocked by the building of dams?
... that the <b id="mwDw0"><a href="./Danube_bleak" id="mwDw4" rel="mw:WikiLink" title="Danube bleak">Danube bleak</a></b>, a <a href="./Fish_migration" id="mwDw8" rel="mw:WikiLink" title="Fish migration">migratory fish</a>, has had its traditional routes blocked by the building of <a href="./Dam" id="mwDxA" rel="mw:WikiLink" title="Dam">dams</a>?