Phenology in Essex: lessons from the past and examples of recent trends 37
and continue to contribute, to our knowledge and understanding. This emphasises the importance of
continuing the recording of biological events, be they phenological or otherwise.
Time series on a whole range of vertebrates, invertebrates and plants are now displaying evidence of
a climatic response. But we are not taking climate change seriously enough. The promise of warmer
weather might initially appear to be desirable. But there will be losses as well as gains. Butterflies,
for example, are warmth-loving species and we might expect them to do well in Britain as climate
warms. Certainly many southern species will be expected to increase their range northwards. However,
many pest species, including aphids, mosquitoes and rats, will also benefit from milder winters.
Phenology warns that changes are happening and, we believe, in a way that is more meaningful to
the person on the street than, say, blandly stating than temperatures have risen by 1.3°C.
The findings reported in this paper suggest that some species respond differently to temperature.
This may mean a change in plant or animal communities that we often mistakenly believe should be
static and attempt to manage with that belief in mind. Some species have been shown to maintain
synchrony with other species they rely on, particularly with invertebrate-plant interactions (Harrington,
Woiwod & Sparks, 1999). However synchrony between invertebrates and animals may be
compromised. There are many aspects of a species' ecology that are likely to be controlled by
phenology; fecundity, survival, distribution amongst them. Wc need to continue archiving old records
and continue recording phenology in order to be better placed to more fully understand ecology.
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Essex Naturalist (New Series) 17 (2000)