This is the largest swift found in the UK.
Males have plain white forewings and hindwings. Females have a yellow/orange forewing.
Flies at dusk and after dark. Groups of males can be seen flying over one spot releasing a goat-like scent.
Overwinters as a larva, maybe twice. Pupates underground among roots.
Grassy or weedy places, on open ground and in woodland rides and clearings.
There are no records in the system yet in Bulgaria.