Data and charts are up to the 18th week of 2026.

There have been an additional 3 moths appearing in the record so far in 2026. The latest is Small Eggar, who put in an appearance in week 12. Previously, Early Moth, who is classed as a winter moth and started it's flight season in 2025, and Spring Usher, who is also classed as a winter moth. Being winter moths, their figures add to the 2025 winter tally. In the case of Spring Usher, this moth is a bit of an anomaly, as it is considered that it may fly from one year to the next, but has never actually risen before the new year. It's demise is what so often ushers in spring

There are two light traps in use at Pitsford Reservoir Nature Reserve. One is adjacent to the reservoir and has reeds and grassland nearby. The 2nd is situated in light woodland. The traps are about 50 metres apart.

Estimates of the effective range of a light trap vary from around 20 metres to in excess of 800 metres depending greatly on the phase of the moon and light pollution. It's also worth noting that although many moths are attracted to light, not all of them are, and the effect of light on each species, and even individual moths within a species varies.

Having trapped the moths overnight the date and the number of each species found in the trap are recorded and the moths, having spent a comfortable night nesting in cardboard eggboxes, are then released.