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Phenology in Essex: lessons from the past and examples of recent trends.
TIM SPARKS', DAVID ROY+ AND CHRIS MASON^
rNERC Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton,
Huntingdon, Cambridgeshire PE17 2LS
^Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ
Introduction
Phenology, the timing of natural events, has a long history within the UK, elsewhere in the Northern
Hemisphere, and in the Far East. It has been particularly connected with the recording of first events,
with the emphasis on the return of spring. This is hardly surprising given the reliance of agricultural
economics on the weather. British history is littered with incidences of rioting amongst the working
classes as food prices escalated following spells of poor weather. So, the coming of spring would
have been viewed as a release from the deprivations of winter - a time for renewed growth and
agricultural activity. During the period 1875-1947 the Royal Meteorological Society co-ordinated a
national recording scheme for phenology and published its results annually. At the same time most
European countries had a network of phenological recorders. In Eastern Europe many of these
networks, originating as a state function, continue to survive. This is also true in Germany, where the
German Weather Service has a network of 2,100 recorders of native and agricultural plants. More
controlled measurements arc available from a network of phenological gardens (the International
Phenological Gardens). These exist from the Balkans up to Finland and contain identical, cloned,
plant material and the intention is to expand such monitoring worldwide.
Closer to home, phenological recording has continued on a more ad hoc basis. Individuals continue
to record events in their diaries and the longer of these are now proving to be particularly useful
(Sparks, Carey & Combes, 1997). The British Naturalists Association has maintained a phenology
recording scheme for most of the current century. Data on particular taxa arc available from research
institutions, for example butterfly monitoring co-ordinated from Monks Wood, moth trapping co-
ordinated at Rothamsted. Information on migrant birds can corne from a variety of sources including
county bird reports, such as that of the Essex Bird Club, and coastal bird observatories.
At Monks Wood we currently have two related phenology projects. The first is concerned with
producing an archive database of historical phenology data. The second is the co-ordination of a
national spring and autumn phenology recording network which we started in 1998 (Sparks et al.,
1998). This paper draws on historic and contemporary phenology data from both these and related
projects for the county of Essex. We show how species are expected to respond to changes in climate
and how species have been responding in recent decades.
Material and Methods
At the time of writing we are about half way through processing the results from the Royal
Meteorological Society's phenology reports. We have abstracted data for Essex for the years already
processed (1891-1927) and for which the number of observers in each year has been variable. Thus
we have a 37 year record of phenological events and have compared these to the Central England
Temperature series (Parker, Legg & Folland, 1992) a series representative of central England and
reflecting conditions for most of Great Britain. In some cases it has been possible to compare historic
dates with those recorded in 1999.
Essex Naturalist (New Series) 17 (2000)