BUTTERFLY REPORT 2013
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2013 BUTTERFLY REPORT Bill Stone and Rob Parker By way of a brief overview, 2013 was a wonderful year for the majority of butterfly species. It was a year of unexpected recovery with the fine long lasting summer weather allowing several species to rebuild their numbers after the disastrous butterfly year of 2012. Everyone will remember it as a great Clouded Yellow year and, hopefully, most of you will have spent some time watching this wonderful migrant butterfly. The Silver-washed Fritillary continued its range expansion and its numbers swelled in the key woodlands too. In addition, some incredible counts of Peacocks, Small Tortoiseshells and both Small and Large Whites were enjoyed during the summer. By contrast the Wall failed to show any signs of recovery and appears to be slipping slowly off the Suffolk butterfly list. Overview of the UK weather in 2013 The annual statistics for the UK in 2013 were generally near average. However, many meteorological records were broken. A late winter and exceptionally cold spring, with unseasonably late snowfalls led into a long warm and sunny summer. October and December saw Atlantic storms that brought rain and at times very high winds, causing widespread disruption. The UK mean temperature of 8∙8 °C was 0∙1 °C below the 1981–2010 average. This is identical to the 2012 value. March was the equal second coldest March for the UK on record. Both March and spring overall were the coldest since 1962. In contrast, July was the third warmest in the series and it was the warmest summer since 2006. The July heat-wave was in marked contrast to the run of recent poor summers from 2007–2012. The UK annual rainfall total of 1086 mm (94% of average) was drier than average but not exceptionally so. May, October, and December were the only months to record above average rainfall for the UK. In both October and December, some parts of the UK received over twice the normal amount of rainfall for the month, and it was the wettest December on record for Scotland. Overall for the UK, it was a sunnier than average year (104%), but again not exceptionally so. It was the sunniest July since 2006 and the third sunniest July in the series from 1929. Table 1. 2013 Weather for East Anglia Season
Mean Temp
Winter 12/13 Spring Summer Autumn
Deg C 3∙6 7∙2 16∙9 11∙2
Anomaly Sunshine Anomaly Rainfall Deg C -0∙8 -1∙9 0∙5 0∙3
hrs 161∙5 453∙9 649∙8 321∙1
% 87 97 110 99
mm 175∙9 125∙9 105 194∙6
Anomaly % 119 92 65 108
Source: www.metoffice.gov.uk Anomalies are measured against the 1981–2010 averages.
Trans. Suffolk Nat. Soc. 50 (2014)