It’s Scotland’s Climate Week and we’re encouraging everyone to talk about nature loss and climate change together, because without nature there is no climate. To get your conversation started, David O’Brien shares his love of monitoring wildlife and explores the effects climate change is having on our species and their habitats.
I’ve loved nature for as long as I can remember. As a young lad, I would go out catching frogs and newts. I still do. Back then, I wrote up my observations in an old jotter; now I use a computer app, but it’s essentially the same process. Like many of us, I’ve noticed changes in the wildlife around me with some species becoming commoner and others less abundant. Of course these may be just one-offs. To really understand what is going on, we need to look at records of species across Scotland over as many years as we can. That’s my day job.
David surveying for amphibians at night and taking DNA swabs from a toad © David O’Brien
Our team gathers the evidence about what is happening to biodiversity (the variety of living things) in Scotland. Globally, there are five main pressures and all of them are having an impact here. These are: Changing use of sea and land, direct exploitation, pollution, invasive non-native species and of course climate change. Behind these pressures are two very important underlying causes: many people have become disconnected from nature and as a result they don’t recognise the value of nature. If people do not feel connected to nature, they won’t care for nature and see its importance. On the other hand, many of us care passionately and the evidence shows we can make a difference.
Looking at the animals for which we have the best data, we have seen a decline in abundance of just over 30% since 1994. We know that there has been a severe drop in the numbers of many species prior to 1994, although our data are not as detailed. This means the actual decrease over the last century or so is likely far higher. We also know that many plants and fungi have also declined heavily over the period, but precise data are not available.
If we focus on a single group, we can get a clearer picture of what is going on. Taking moths as an example, we’re seeing a marked decline. Many of us overlook moths, they’re less glamourous than butterflies, but they are important pollinators and they also act as food for many of our familiar birds and other animals. We looked at nearly 300 types of moth, and the most common cause of decline appears to be loss or damage to their habitats.
One of our key pressures is, of course, climate change. We have already seen declines in some of our internationally important seabirds as their prey species are lost due to warming waters, in some cases exacerbated by historic overfishing. Our models suggest that drought will become increasingly important, especially for freshwater species and we are already seeing some impacts on more sensitive plants.
On the positive side we also have examples of improvement. When I was young, most of our lowland rivers were highly polluted. The air in our towns and cities was toxic to lichens and mosses and this was mirrored in human health. Pollution controls introduced in the 1990s have benefitted many species through improvements to freshwater and air. Mosses and liverworts are good indicators and we have seen an upturn in sensitive species. Similarly freshwater invertebrates like mayflies have seen very large increases in their distribution.
The twin crises of climate change and biodiversity loss are daunting. The evidence shows they are affecting wildlife here in Scotland. But the evidence also shows that working together, we have tackled environmental problems in the past. I believe that we will again.
David O’Brien is Biodiversity Evidence and Reporting Manager at NatureScot.
Scotland’s Climate Week runs from 26 September to 2 October. Learn more and get involved at https://www.netzeronation.scot/whats-happening/scotlands-climate-week.