A cool start to spring meant that early-emerging species of butterflies and dragonflies were slow to appear. However, the weather then turned into a roller-coaster of mini heatwaves, followed by wind, rain and cold culminating with a rather disappointing summer.
(Keith Powrie, an expert in lepidopterology and odonatology, has undertaken regular surveys of Knoll Gardens on behalf of the Foundation since 2009.)
While the dismal summer brought very low numbers, higher counts early and late in the season lifted the final figures above the annual average. Best performers were the Speckled Wood, with at least one being seen every week, Red Admiral, Meadow Brown and Comma. The Silver-washed Fritillary made a welcome return while Orange Tips and Large Skippers did well.
Dragonflies / damselflies
The warmer spells in late spring meant that both dragonflies and damselflies appeared earlier than in 2016 and numbers exceeded last year’s count. Three uncommon species, not seen last year, made a welcome reappearance in the Gardens; Beautiful Demoiselle (Calopteryx virgo), Emperor Dragonfly (Anax imperator) and Golden-ringed Dragonfly (Cordulegaster boltonii). The disappearance of the Four-spotted Chaser (Libellula quadrimaculata) this year meant that the total number of species in the garden was 15.
The full 2017 report (pdf) can be viewed here: Knoll report 2017