Falco hypoleucos is infrequently seen over much of arid and semi-arid Australia. Its range covers eastern Australia, especially arid regions, and northern Australia south to approximately 26^oS, south of which it is casual in occurrence³. It may have been eliminated from some breeding areas early in the 20th century, particularly those with more than 500 mm annual rainfall in New South Wales, where its eastern limit has also shifted further inland since the 1950s². The contraction in its breeding distribution over the past few decades¹ is attributed to habitat degradation, which has reduced the suitability of some semi-arid habitat and restricted the species to the arid zone². The main breeding distribution now covers areas where annual rainfall is under 250 mm¹. The present range is believed to be stable, and it is apparently more widespread during inland droughts. There is evidence of regular seasonal movements between the arid zone and northern Australia, and possibly New Guinea, and from west to east in Queensland. It is always found at very low densities, and its population is believed to number only 1,000 breeding pairs and no more than 5,000 individuals in total. These estimates are based on limited information about the species and comparison with data for the Peregrine Falcon Falco peregrinus⁴. The population of F. hypoleucos is thought to be stable.