Biodiversity - the comparison from 1976 (Focus - April)

In the long hot summer of ’76, I was working on the gunnery ranges at Lulworth. I seemed to get home every night either white with chalk-dust thrown up from the parched tracks or black with soot from fighting fires on the heath. At the time it felt like a never to be repeated heat and drought but now we are growing accustomed to annual, albeit shorter, heatwaves. Looking at things positively, it was believed that the heath fires across Purbeck weren’t entirely a bad thing as encroaching scrub was burned off helping heath habitat to recolonise. Now though, such fires are so frequent, some less mobile species are wiped out without time to re-establish.

At the other extreme, we have all been talking about the wretchedly wet winter we have just endured but surprisingly it wasn’t a record breaker. Martinstown in Dorset still holds the UK record for the highest rainfall in one day (July 1955: 11 in) but this was far exceeded more recently for any 24hr period at the Honister Pass in Cumbria (Dec 4/5:13.4in). These torrential downpours are becoming more common as warmer air can absorb more water before depositing it and if the storm cell is slow moving that can cause flash flooding.

If we are asking ourselves what is going on with the weather, imagine what it must be like for wildlife. Their life cycles, feeding habits and preferences are geared to less variable seasons so rapid changes or extreme conditions can have a severe impact. Even healthy, sound looking trees which have grown up over decades with their form and roots adapted to a prevailing south-westerly wind can be uprooted by a “freak” storm from another wind direction. 

There are species which CAN cope, and they are the ones which can flourish in these new circumstances. Species of birds, insects and plants are colonising from the continent, and some are extending their ranges northward as the climate warms. At the same time, global trade has allowed the introduction of species from afar, although all too often these to become pest species when they flourish without their native predators.

Many of these are attractive and exciting additions to our fauna, but unfortunately, over the last 50 years, our native biodiversity has in general declined. It is only by visiting sites of my youth and remembering what they looked like then, what birds and butterflies could be seen and in what numbers, can I recognise that I too am subject to the ‘shifting baseline syndrome’. This is where we either are unaware of, or forget what things were like before and accept the current situation as normal when in fact it is diminished. Rewilding projects show how wildlife can recolonise and flourish given the right conditions but on their own these will never be enough. Much needs to be done to ensure that the decline in biodiversity since 1976 does not continue for the next 50 years.

​Andrew Graham