BUTTERFLY REPORT 2004
111
2004 BUTTERFLY REPORT ROB PARKER Following on from the outstandingly good 2003 season, the much wetter 2004 has seemed an anticlimax, yet butterfly numbers have not been low. Indeed, some species, particularly the Whites, have produced higher counts than they did last year. High populations at the end of 2003 carried through another mild winter to produce a good start for most of our resident species. Silver-studded blues hit record counts at Minsmere, and had mixed results at other colonies. There was also some good news from our strongest Dingy Skipper colonies. Migrant Painted Ladies and Clouded Yellows were seen, but in much lower numbers than in 2003. A flurry of Swallowtail sightings in Ipswich and a single Camberwell Beauty added interest to the season, but may have been releases rather than genuine visitors. The long-term decline of a few once-common species continues to cause concern, though there were no dramatic downturns, just weak turnouts of Graylings at 2 transect sites and reduced evidence of Wall Browns away from the coast. Weather Average temperatures were again up on historic averages, but sunshine was only average, and rainfall was high, particularly in the summer months. The table below shows mean temperature, sunshine for and rainfall for East Anglia, all presented as anomalies compared to averages over the period 1961 to 1990. The frequency of wet summer days inhibited recording activity as well as restricting mating opportunities fir the insects, but lush foodplant growth may have benefited larvae to some degree. Table 1. 2004 Weather for East Anglia Season
Mean Temp °C
Anomaly % up
Sunshine hrs
Anomaly %
Rainfall mm
Anomaly %
Winter Spring Summer Autumn
5·1 9·5 16·9 11·4
1·3 1·3 1·3 0·9
180·8 445·5 560·9 342·8
108 100 99 108
181·6 136·4 250·2 163·4
126 98 162 100
Source: www.metoffice.gov.uk/climate/uk Anomolies are measured against the 1961 to 1990 averages.
Monitoring the BAP Species This year’s Dingy Skipper survey (Annex E) eliminated a number of former sites as lacking suitable habitat, whilst confirming that the known colonies in the King’s Forest, RAF Barnham and Center Parcs were all in good health. Indeed, the extent of the Kings/Wordwell colony was found to be greater this
Trans. Suffolk Nat. Soc. 41 (2005)