Results from Bee-fly Watch

Bee-fly Watch has been running since 2016, and since then 24,492 records of the four species of Bombylius bee-fly have been contributed. The main purpose of Bee-fly Watch is to encourage people to enjoy watching bee-flies! In addition, the records help us to monitor changes in the distribution and flight period of the flies. 

Chart of Bee-fly Watch records per year

The four species are:

English name Scientific name Flight period and distribution Earliest ever sighting
Dark-edged Bee-fly Bombylius major A spring species (most records in March–May), widespread and common across the UK except in upland areas 9 February (in 2022)
Dotted Bee-fly Bombylius discolor A spring species (most records in March–May), fairly common in southern parts of England and Wales, range expanding northwards 15 March (in 2017)
Western Bee-fly Bombylius canescens A summer species (most records in May–July), fairly common in Wales and south-west England, and appears to have been lost from the more northerly parts of its former range 26 April (in 2020)
Heath Bee-fly Bombylius minor A summer species (most records in July–August), restricted to sandy habitats in Dorset and the Isle of Man 23 June (in 2020)


Flight periods

Thanks to the Bee-fly Watch records, we know that the timing of bee-fly emergence each year is closely tied to the temperature and sunshine levels in early spring. In 2023 we had a relatively cool spring, and bee-flies were very late to emerge, but then rapidly climbed to a peak at the beginning of April. In contrast, 2022 got off to a very early start in a warm weather, but the peak in April was much less pronounced.

Chart of Bee-fly Watch records per year



Distribution maps are shown below, based on all the recording scheme records for all years. To explore the maps in more detail visit the map pages on iRecord:

Dark-edged Bee-fly Dotted Bee-fly Western Bee-fly Heath Bee-fly


Chart of Bee-fly Watch records per year


A summary of the Bee-fly Watch records from 2023 can be seen below.