Phenology, as already mentioned, is the study of the recurring natural events such as date of first flowering, first arrival or departure of migratory birds, the commencement of the hayfever season etc.

Phenology therefore assists in understanding processes in agriculture, forestry, biodiversity, human health and climate change.

Like weather records, phenological records are of greatest value if collected over the long-term. For trends or patterns in phenology to be determined records covering at least twenty years are required (Gornik 1994 in Menzel 2001).

The Bureau of Meteorology can tell us if a particular day is hotter or colder than the average or the warmest on record because they have long-term, reliable records. So to be sure of what the average date of the commencement of the hayfever season is or whether dandelions are really flowering earlier than they used to, we need records covering 20 years or more.

Interestingly in 1909, the then Commonwealth Meteorologist wrote

In the United Kingdom phenological variables are recognised by the government as a valid method of monitoring climate (Sparks et al. 2000).

Is there evidence of the effects of climate change in Australia?

We really can't be sure, as we don't seem to have the long-term records required (hence this website) as illustrated by the figure above (source http://www.ipcc.ch/ - WG II "Climate Change 2001: Impacts, Adaptation and Vulnerability"). We are, however, searching for old records. For example, the Forestry Commission of New South Wales commenced recording flowering dates in the early 1930s, and were apparently still keeping records during the 1950s --- but we don't know where this information is now.

So if you have any old phenological records, or know where some are located please contact us!!! (email mrk@unimelb.edu.au) Some records have already been located - the Forest Commission of Victoria examined budding and flowering on a quarterly basis although some officers recorded on a monthly basis between 1933 - 1981 (Keatley et al, 1999). These records are by no means complete; data are available for 43 locations only, although another 49 sites are mentioned.

Understanding phenology is also important for the management of endangered species. One example is the Regent Honey Eater (Xanthomyza phrygia) which is considered endangered in Victoria.

This species is a nectar-feeding bird that relies on the flowering of certain eucalypt species e.g. Red Ironbark or Mugga (Eucalyptus sideroxylon), Yellow Box (E. melliodora), White Box (E. albens), and Yellow gum (E. leucoxylon).

The Victorian Department of Natural Resources and Environment has developed a Recovery Program for the species. Some of the actions of the program include monitoring population fluctuations and the flowering of these eucalypts. Clearly, both of these activities are applications of phenology.

Finally, by recording phenological information we can develop our scientific memory. By understanding how flora and fauna behaved in the past, we have a better understanding of what is 'now' being observed and possibly how species may react to a change in climate (Sparks, 1999).

References