Trainee Ecologist, Genevieve Dalley, introduces us to the world of freshwater invertebrates.
Through the looking glass
Water is a mysterious thing. When looking at it, most people see nothing more than a reflection. But, if you slip past the surface, there is a whole other world waiting, with its own stories and an alien set of characters.
Here, there really are fairies, dragons and monsters of the not-so-deep...
Blue-tailed damselfly (Ischnura elegans).
Emperor dragonfly larvae (Anax imperator).
Water Scorpion (Nepa cinerea).
My new job as a Trainee Ecologist, specialising in freshwater invertebrates, allows me to delve into this secret world. And I would like to bring others with me.
So, let me introduce you to a lesser-known star of the stream. This is the story of the Orange-striped stonefly.
The orange-striped stonefly. Taken at Dovestone RSPB reserve by Ken Gartside. Photo via www.WildaboutBritain.co.uk.
Stoneflies (Plecoptera) are ancient insects, with the first fossils dating from 250 million years ago. They live as larvae in freshwater, sometimes the formidable top predators of their habitat, until they reach the correct size and emerge as flying adults. However, unlike more familiar insects, such as butterflies and moths, stoneflies do not have a pupal stage between young and adult.
Stoneflies require high oxygen levels and so are very sensitive to organic pollution in freshwater, which reduces the amount of oxygen available to them. They are therefore very good indicators of water which does not contain organic pollution. Interestingly, many species are not so sensitive to heavy metal pollution, with healthy populations found downstream of disused lead mines.
The Orange-striped stonefly (Perlodes microcephalus) is widespread throughout Europe. It was previously believed that all stoneflies identified in Britain as P.microcephalus were the same species. However, recent work has revealed that Britain in fact has its own species, the British Orange-striped stonefly (Perlodes mortoni), now classified as a new, separate species found only in the UK. This exciting discovery means that the distribution and conservation status of both P.microcephalus and P.mortoni in Britain is thrown into question.
The two species look very similar. It is not yet possible to tell the larvae apart. In fact, the only way to distinguish between them is by differences between the structure of the eggs and the length of the wings on an adult male. P.mortoni adult males are flightless, with their wings reduced to stubs, while P.microcephalus males have a range of wing lengths, some with fully formed wings. To confuse things further, females of both species have fully formed wings.
These stoneflies can be seen as adults between March and July. However, the peak emergence period is May, so now is the best time to see them. Orange-striped stonefly adults are quite big (males: 13-18mm, females: 16-23mm) and, as the name suggests, the adults have a very visible orange stripe running from the top of the head and across the prothorax (the first body section after the head). You can look for them beside rivers and streams, sheltering under rocks, crevices and other structures such as bridges.
Adult male Periodes mortoni, the British orange-striped stonefly. Photo via www.riverflies.org.
It is important to learn more about the species so we can protect them. If you come across an Orange-striped stonefly it would be very helpful if you could collect it and send it to the Riverfly Recording Scheme. For more information on this, visit the Buglife website, the Riverflies Trust website, or contact: firstname.lastname@example.org.
By doing this, you will be giving vital information on the status of the species in Britain and helping to conserve this beautiful and important animal.
Scotland's Grand Canyon- a tour of opencast coal sites in East Ayrshire
One of the perks of working for a nature conservation organisation is the occasional opportunity to get out of the office and see colleagues in action and the special places for wildlife we fight for.
Over the past year, RSPB Scotland staff have been working to highlight the sorry state opencast coal mines have been left in across Central Scotland, following the collapse of the two biggest surface mining companies last year. We are pressing for action on restoration, and robust regulations to ensure the same problems don’t happen again. Regional staff have visited these sites on many occasions over the years, but we decided it was high time some of us less familiar went to see the impacts first hand.
So, on a grey Monday morning, we were whisked away for a ‘grand tour’ of East Ayrshire’s opencast coal mines. Before long, we started to spot mountains of overburden- a mix of soil and rock dug out of the massive opencast pits - metres from the main road.
Our first stop was the now derelict site at Powharnal, near the village of Muirkirk, which was mined by Scottish Coal - at the time, the largest mining company in Scotland and second largest in the UK. After crossing a small woodland, we were on the site [Please note: there is no right of access to these sites and any visits must be authorised by the landowner]. What we didn’t know immediately, gazing across a ‘loch’ that looked to be about 20 hectares, was that below the surface lies a ‘void’ of at least 50 metres deep, filled with ground water. A few gulls bobbed along the surface, surrounded by steep slopes of the overburden mounds.
Walking on the edge of the void at Powharnal.
Unsurprisingly, the flooded voids at this and other sites are causing serious concern for local communities, and the water level looked alarmingly high, and within just a few metres of the road and River Ayr.
What strikes you walking around the site is the sheer scale of it. We trouped to the top of the overburden mound and were greeted with a view of more of the same. You’d be forgiven for thinking that such operations must, surely, be located well away from sensitive wildlife areas.
But unfortunately, perhaps the most shocking fact about the Powharnal site is that a big chunk of it, about 100 hectares, is within the Muirkirk and North Lowther Uplands ‘Special Protection Area ‘ or SPA, protected under EC law. ‘Special’ because it is considered prime habitat for breeding populations of hen harrier, short eared owl, merlin, peregrine and golden plover. The habitats that support these birds, and a wealth of other species, include important areas of peat bog. What the picture shows below is the 45 degree angle of the overburden, smack in the middle of the SPA.
Overburden smack in the middle of the SPA.
So how did the site come to be left in such a state? Allowing mining in a protected wildlife site doesn’t exactly sit well with the Scotland’s reputation as a country which values its special places for nature, or its ambitions to transition to a low carbon economy. Seeing the site was certainly a harsh reminder of the consequences of our energy-hungry lifestyles. It was an interesting experience to relate my own energy use to the landscape right in front of me.
Open cast coaling was nevertheless big business in Scotland until last year, when Scottish Coal and ATH Resources collapsed. It became apparent that there would be massive difficulties in restoring several sites left behind, including at Powharnal and also Grievehill, another site overlapping the SPA. These sites were consented on the strict basis that restoration standards would be high, to avoid breaching European law.
Even though the companies originally set up financial bonds - insurance policies to ensure restoration happened in case they went bust - it emerged after their collapse that the bonds were massively inadequate. The shortfall has been estimated at £200 million across Scotland, with the majority of this in East Ayrshire.
Looking at the images here, you can see the enormity of the task at hand. How do you shift that much earth, truck by truck, and begin to bring nature back to the area? And who is going to pay for it? With the issue of breach of with European law (and associated heavy fines) looming, clearly a plan needs to be put in place as a matter of priority.
View of the void at Powharnal from the top of the overburden mound.
After our walk through Powharnal, we stopped for a quick view of the Duncanziemere site where coal is still being extracted by Hargreaves, one of the few remaining operators. We expect to see an application to extend this site soon. Across the road is Low Moss - a lovely example of a raised mire habitat, with the sound of birds enjoying it. Whilst it doesn’t seem right that any new sites should be consented until we have sorted out the restoration challenge, at the very least we hope that any new plans will avoid the most sensitive areas. Otherwise, an extension could wipe out an important home for nature.
Our last stop before heading back to the office was in the valley housing the adjoining Greenburn and House of Water sites. The former is operated by Kier Mining, and the latter has been taken over by Hargreaves but is a big part of the ‘restoration challenge’. The view from here was perhaps the best example of the day of what can happen when mining continues across and defines an entire landscape. I have been to the Grand Canyon in the US, and the exposed seams at these mines reminded me in no small way of the spectacle. Let’s hope that we see concrete action on restoration soon. And let’s hope that these areas are supported to transition away from industry that is continuing to leave a damaging industrial legacy in Scotland.
Conservation Manager Stuart Benn meets the winners of the RSPB Scotland Photographic Competition
One of the best bits of my job is getting to meet up with great people and so it was this week when I got a couple of days out with some of the winners of the RSPB Scotland Photographic Competition.
Day one was with Andy, Dominic and Eric and having won a photographic competition, they wanted the chance to take more pictures so I took them to one of my favourite spots near Loch Ness. Despite the cool wind and showers, the ring ouzels sang, the spotted flycatchers snapped passing midges, the swallows and martins zoomed by and common sandpipers skittered off. A really enjoyable day though I don’t think we ever quite managed to get the wildlife and photographers in precisely the same place at the same time to get that killer image.
Emma takes the controls
On day two, I met Lesley and her niece, Emma, at Loch Garten where we were given a privileged behind the scenes look round Operation Osprey by Jen Clark. This is a special year at Garten as it is 60 years since ospreys returned here as a breeding bird in the UK and, all being well, their 100th chick will fledge too so this really was a special treat. Emma even got to operate the nest cameras and there’s not many people get to do that!
And at the feeders, a red squirrel scurried about and posed for the cameras – one for next year’s comp perhaps?!
Red squirrel at Loch Garten (Lesley Garven)