Great bustards Otis tarda in Morocco: status in spring 1999 and evidence of a decline in recent decades

A spring (1999) census was conducted of successful breeding in 1998. We argue that the small number of birds, a population sex ratio of 1 : 3.3 in great bustards Otis tarda in north-western Morocco, favour of females, evidence for a range contraction, and where a poorly known population of this species oc- curs. Sixty-four birds were seen in four distinct areas. probable isolation from other great bustard populations mean that this population is now extremely endan- Adult males were seen displaying at three of these areas, indicating that they are probably traditional lek gered and will decline to extinction unless conservation measures are implemented immediately. sites. No adult males were observed in the fourth area and its status as a lek site is uncertain. Two further sites