Nocturnal bird migration in Mauritania — first records

Summary Nocturnal autumn bird migration was studied for the first time along the southern edge of the western Sahara. A passive infrared device provided data on the intensity and direction of nocturnal passage at 9 different sites for 20 nights from dawn to dusk. The results support the idea that many bird migrants use an intermittent flight strategy when crossing the Sahara. Flight directions along the southern border of the desert were SSW, similar to those known from southern Spain, and thus, did not confirm the expected shift towards SE before the desert crossing, as derived from former laboratory experiments.