In some unknown circumstances, the species was reported to exhibit aggregations. From May 2009 to August 2011, circularly-moving groups were consistently observed by snorkeling at the same location in a stretch of the Rhône River downstream of […]
In some unknown circumstances, the species was reported to exhibit aggregations. From May 2009 to August 2011, circularly-moving groups were consistently observed by snorkeling at the same location in a stretch of the Rhône River downstream of […]