The Unfurling Beauty

If I could only have the patience of plants. They wait patiently for the soil temperature to reach the desired level, as a result of the sun rising higher in the sky to set a new energy production system into motion. These miniature factories provide the food/energy source for all other creatures. That includes the microbes and soil animals which recycles the plant and animal debris. There is no waste in Natures’ household. Now that the trees are getting dressed the birds can hide their newly designed or reused nest. The chorus of territorial banter and the sweet melodic companion seeking tunes ring from the habitats close to the farm residence on Cloncannon Biofarm. There is so much happening almost inspite of our notice, for example, the plants are competing for space, sunlight, water and mineral resources. They are also trying to adapt strategies to avoid getting eaten by bugs/pests. They may have a tough outer cover on the leaf like the laurel or have thorns like the thistle, bramble, hawthorn, blackthorn, or holly. The bugs have emerged from a dormant or egg stage and they too are busy with family life and survival.

But is all well and stable within these natural cycles of leaf bud emergence, insect first flight periods and bird migratory timing? The study of the timing of these recurring life cycle events in plants and animals is called phenology and the events themselves are called phenological phases.  A pan European study, using records from 20 european countries (50 sites) investigated  these  timing events. In Ireland, tree phenology recording took place at four sites (Valentia Observatory, Co. Kerry; the National Botanic Gardens, Dublin; Johnstown Castle and JFK Arboretum both in Wexford), since this network was established in the 1950s. At that time clones of a suite of trees were distributed to the 50 sites with the intention of investigating the impact of local climate on the phenological phases such as, bud burst, leaf unfolding, flowering, leaf colour and leaf fall. The results showed that the overall trend was for leaf unfolding to be occurring nearly three weeks earlier in 2008 than in the 1970s. This trend has, at least in part, been attributed to rising spring temperature.

A 30 year study of the timing of migratory bird arrival from sub-Saharan Africa to Ireland showed that only 2 of the 11 species investigated arrived at later times, with the other nine arriving earlier. The species of birds and the trend is outlined in the table below:

Common Cuckoo                                                     Later

Common Swift                                                         Earlier

Sand Martin                                                             Earlier

Barn Swallow                                                           Earlier

Common house martin                                          Earlier

Whinchat                                                                  Earlier

Northern wheatear                                                 Earlier

Common grasshopper warbler                            Earlier

Sedge warbler                                                          Later

Common whitethroat                                            Earlier

Willow warbler                                                        Earlier

This trend has, at least in part, been attributed to rising spring temperature.

In relation to insect phenology, analysis of a suite of moth species has shown that appearance dates and flight periods are correlated with spring temperature.

What is the message to be taken from these research initiatives? What are the consequences if any of an earlier spring? The potential consequences suggested include:

(1)    An increase in timber production as the leaves will be on the trees for longer and photosynthesising for a longer period producing more biomass.

(2)    More carbon dioxide will be removed from the atmosphere – again due to the leaves emerging earlier and therefore living longer.

(3)    An earlier start to the pollen season.

But in temperate regions many trees need cold winter temperatures for budburst to occur, and if the winter temperatures rise this ‘chilling’ may not be fulfilled and young leaves emerging earlier are then susceptible to late frost damage. So, overall there will be some gains and losses related to earlier leaf unfolding.

Looking at how individual species respond to rising spring temperature is not adequate. Since there are so many connections/interactions among species, we need to assess likely impacts at ecosystem level. How are the relationships affected? The timing of these interdependent phenophases must be synchronised. Recent studies have shown that the some migrant birds that feed on caterpillars are arriving earlier but not quite as early as it should be to benefit from the peak supply of food. This will mean a reduced supply of caterpillar food supply for the migrant bird chicks and possibly a greater availability to the resident bird species.

Let us not leave out humans as we assess climate change and impacts on Natures’ web of life. The recently published document from the Intergovernmental Panel on Climate Change highlighted the urgency for actions that alter how the human species are impacting negatively on the planetary systems. For many years we have been hearing about loss of arctic ice masses. Climate change impacts on lowlying coastal human populations and on crop productivity and poorer countries is highlighted in the IPCC Report. Extremes of climatic conditions are making it more difficult for scientists to model future planetary security for ecosystem stability. Humans will it seems learn quickly from ‘Nature’ how to adapt to climate change. Nature has being doing it for millions of years.

Even at farm level at Cloncannon Biofarm there are examples/lessons of adaptability to be learned, taught, qualified in,  in order to be ‘Masters’ of sustainable living. For example, for the first time in my memory there are three geese on this farm. There was some small feathers and goose down in there holding pen but this was soon spotted by the starlings and they were busy going with beak fulls to line their nests. Similarly, there was three small ponds constructed on the farm in November and it is delightful to spot a nest strategically placed above the water line, tucked in under the tuft of grass on the pond edge. The grey wagtail is most welcome to share this beautiful spot. We humans must take note of these creatures adaptability and their emphasis on needs rather than wants. Living in communion with all the other creatures. The wisdom of Nature, we are not superior to it.