118 BR. J. ENT. NAT. HIST., 7: 1994 



FIELDWORK AT DINTON PASTURES TO THE END OF 1993 



Peter Chandler 



There were three field meetings and several workshop meetings involving some 

 fieldwork at Dinton Pastures from the completion of the society's building in 

 1992 and additional fieldwork was done on the Diptera throughout 1993. Information 

 on the insect fauna of the Park was thus accumulating although much remained to 

 be done. 



The meeting on 20. ix. 1992 was the inaugural open day at the building and a minority 

 of those attending attempted fieldwork although a good start was made in several 

 orders. There had been light trapping near the building by John Muggleton on the 

 previous night and the weather was good for daytime collecting. A surprising range 

 of species was recorded although the park showed evidence of the recent years of 

 drought, with MungelPs Pond significantly lower than it was throughout 1993. 



The two field meetings in 1993 were affected by variable weather conditions and 

 less well attended but the daytime meetings were enjoyed by those who came. On 

 15.v despite predictions of bad weather the morning was fine although windy but 

 sufficient shelter was found behind the hedges on the west side of Black Swan Lake. 

 After a short shower in early afternoon, the sun broke through to illuminate afternoon 

 collecting by the river Loddon. It rained again later and the evening was cold and 

 windy, so that any idea of light trapping had to be abandoned. 



The meeting on 18.ix enjoyed reasonable weather during the day. Most of the 

 morning was spent by Mungell's Pond but an afternoon circuit reached Middle Marsh 

 and Sandford Lake. The sky was clear and the evening cold so conditions were far 

 from ideal although better than on many nights in the preceding weeks; it was, 

 nevertheless, decided to try light trapping and David Young ran two lights in the fields 

 adjacent to the Country Park Office until 1 1 .30 pm and a few moths were recorded 

 at the security lights around the buildings; he also tried sugaring trees in the vicinity 

 but this attracted only earwigs. 



The findings on these meetings and other useful records obtained on other occasions 

 are detailed under the relevant order so that some idea can be given on the progress 

 made in each group. 



Lepidoptera. A booklet produced by the Local Authority in 1985 (on sale at the 

 Country Park Office) included a list of 30 species of butterfly which had by then 

 been reported from the park, several of them single sightings. Only eight species of 

 butterfly were observed in 1993, although it was a poor year for them generally. 



Bill Parker has periodically run light traps near the buildings over several years, 

 but his records were lodged with the park authorities and except for one September 

 visit have unfortunately been mislaid. Thus there are three lists now available for 

 that month. The 1992 field meeting recorded 28 species, but in 1993 only 17 species 

 were noted, 12 of them in common. 



Fortunately there had been a field meeting of the Reading and District Natural History 

 Society at the Park on 13.vii.1990 when lights were run near Mungell's Pond and 

 48 species were recorded (communicated to me by Brian Baker). A few other species 

 have been recorded on day visits and Colonel A. M. Emmet reported 18 species, mostly 

 "micros", on the occasion of the opening ceremony on 27.vii.1993. The latter included 

 Caloptilia rufipennella (Hiibn.) (vacated mines and tenanted cones on sycamore), 

 believed to be new to Berkshire. Ron Parfitt has recorded Nephopterix angustella 

 Hiibn., which he reared on 29. vi from larvae mining berries of spindle tree. Caterpillars 

 of Tyria jacobaeae L. were much in evidence on ragwort during the summer. 



