Essex and London Ladybird Survey, 1999
Table 1 Ladybird species recorded in Essex, 1999
The occurrence of years of population outbreak is well known (e.g. Burton, 1998; Majerus and
Majerus, 1996) but less is written about years of low abundance. The weather is most likely to be
the responsible factor and while 1999 was one of the wannest years on record, there were three
unusually cold weeks in mid-April, early June and mid-November (Hulme, 1999). Coincidentally
there were similar cold spells at exactly the same dates in 1998. It is possible that the cold third
week of April in 1998 initiated a population decline especially as it followed a warm winter and
March with ladybirds emerging early from hibernation. Both years had above average rainfall,
especially in April. These spells of bad weather could cause direct mortality of all ladybird life
stages and also of aphid prey. A longer time series will be necessary before any serious conjecture
can be made.
Essex Naturalist (New Series) 17 (2000)