Abstract

The Common Nighthawk Chordeiles minorremains a very rare autumn vagrant to Britain from North America, with only 27 individuals recorded between 1927 and 2022. It has occurred mostly in September and October, with one record in early November, and the majority of birds involved have been recorded as immatures. Of the vagrants so far documented in Britain, five were reported as males, four as females, 12 as juveniles or immatures, three as adults and seven as of indeterminate age or sex. Most of the birds survived their journey of almost 4,200 km across the Atlantic Ocean, but six were either found dead or died shortly after their initial discovery. Only one bird reported from Britain has so far been identified to race. Subspecies are separable by coloration and size and are usually not readily identifiable in the field, especially away from the breeding grounds. It may occasionally be possible to assign some birds to a group of subspecies, especially if their general coloration is seen well. Of the six vagrants that died, five were found dead while the sixth was shot, but only four of the corpses were preserved; three are currently housed in museum collections and the fourth is privately held. Examination of some of these preserved specimens reveals that two distinct subspecies, ‘Eastern Nighthawk’ C. m. minor and ‘Chapman’s Nighthawk’ C. m. chapmani, have occurred in Britain, while photographs of living birds suggest that other races might also have found their way here. Should any future vagrants be found dead or dying, finders should be encouraged to recover and freeze the corpses as soon as possible after discovery and donate them to a natural history museum for preservation and identification. This should, of course, be done within the legal frameworks and with landowner permission. Although no potential splits are currently under consideration, it would nevertheless seem important to document which populations might be subject to vagrancy to Britain.Introduction