Spring 2012 - Glasgow & SW Scotland Branch of Butterfly ...

Pearl-bordered fritillaries (PBF) had a bumper year at our Mabie Forest
reserve south of Dumfries. 500+ individuals were recorded on one visit,
with reports of these rare butterflies jostling for space on every available
dandelion flower! Record numbers were also counted on the reserve’s
butterfly transect by Jessie Wormell in April, however the poor weather
in May prevented many visits during the butterfly’s peak flight season.
Jessie has kindly provided the Annual Index (roughly equates to
numbers seen over the flight period) for PBF over the last few years for
comparison: 2008 = 56, 2009 = 243, 2010 = 494, 2012 =761! The
recent increases appear directly related to conservation work by
volunteers helping to clear scrub along the forestry tracks, which has
benefited violets, the PBF caterpillar food plant.
Dingy Skippers also had a great spring, with record-breaking numbers
seen at a couple of locations along the Solway coast, and the discovery
of a healthy new colony at a brownfield site near Rankinston in Ayrshire.
This is the most northerly sighting in Ayrshire for over 100 years! It’ll be
interesting to see if other colonies can be found nearby in 2012.
Stormy weather hit Scotland at the end May 2011 and devastated much
of the vegetation on the west coast. It also appeared to wipe out many
of the adult butterflies that were on the wing at that time. I personally
didn’t see any white butterflies around Glasgow for about 3 weeks after
the storm! The table below shows a summary of butterfly sightings
during the year. You can see that Large, Small and Green-veined
Whites all had a poor year.
Summary of SW Scotland Butterfly Records during 2011 (updated 29/02/2012).
Species
Number seen
2011 (2010) (2009)
20 On the Spot – April 2012
Earliest /latest
Sighting 2011
10km
squares
2010 (new)*
Chequered Skipper 95 (294) (592) 4 th May / 14 th June 3 (0)
Small Skipper 15 (0) (0) 24 th July / 27 th July 1 (0)
Essex Skipper 69 (0) (2) 23 rd July / 9 th Aug 1 (0)
Large Skipper 96 (100) (15) 29 th May / 9 th Aug 14 (2)
Dingy Skipper 216 (39) (142) 1 st May / 1st July 9 (1)
Clouded Yellow 4 (2) (2) 6t h June / 7 th Oct 3 (0)
Brimstone 0 (0) (1) / 0 (0)
Large White 480 (2,074) (808) 18 th April / 9 th Oct 75 (2)
Small White 932 (3,986) (1,123) 10 th April / 7 th Oct 94 (2)
Green-veined White 5,903 (8,136) (7,377) 11 th April / 28 th Sept 194 (0)
Orange-tip 2,983 (2,390) (1,993) 10 th April / 13 th July 131 (12)
Green Hairstreak 572 (805) (570) 18 th April/ 23 rd June 32 (7)
Purple Hairstreak 258 (626) (47) 16 th July / 27 th Aug 13 (2)
Small Copper 515 (737) (569) 24 th April / 9 th Oct 99 (2)