On the day we arrived at the ringing station, Anton Liebermann told us about an unusually small Nightjar that had been caught some days before. He was keen to target Nightjars and hopefully catch another small individual. We were equally enthusiastic and agreed to get some extra nets up to target Nightjars at dawn and dusk. On the 17th Chris did the first round of the day and returned with two Nightjars. One was considerably smaller than the other. To add to the intrigue, both birds were assessed as 3Ms, but wing measurements were 181.5mm/197mm and weights 46.5g/63g with both birds having fat/muscles scores of 1 and 1. The wing points were checked and found to differ. Full primary measurements were then taken for both birds along with feathers for DNA analysis.
3M undetermined Nightjar species
European Nightjar and unknown Nightjar species
Unknown Nightjar compared to European Nightjar
After further Internet research we were still unable to determine exactly what the small Nightjar might be. There were plenty of species that it didn't appear to match but a species known from one individual collected in China in 1929, Vaurie's Nightjar, could not be ruled out.
Another small Nightjar was captured on the 21st and although it was a little larger than the individual described above, it had the same P2=4/5 formula, unlike the larger birds with P2=3/4 .
We eagerly await the results of DNA analysis that may provide some clarity regarding the identity of these small Nightjars.
