Today's blog post comes from one of two trainee ecologists in RSPB NI - Anne Guichard.
As a trainee ecologist with the RSPB, I have the chance to explore our natural world and learn about its wonderful creatures and the different ways we can manage habitats to help them. Our conservation work at Portmore Lough has led to 11 species of damselflies and dragonflies regularly breeding on the reserve ground. A single banded demoiselle was spotted there in July which hadn’t been recorded on site since 1996, and we are hoping for more species to breed on the reserve in the future. So before summer ends, I’d like to share with you some of the amazing things I’ve discovered recently about dragonflies and damselflies.
Brown hawker (Aeshna grandis) and emerald damselfly (Lestes sponsa) at Portmore Lough
A bit of background: Dragonflies and damselflies in Ireland
11 species of damselflies and 13 of dragonflies are resident in Ireland. They both belong to the order odonata (meaning ‘toothed jaw’ in ancient Greek) and were among the first flying insects to appear on earth. As some of the largest and most colourful insects in Ireland, the dragonflies and damselflies are easily identified in the field. They are carnivorous and can hunt prey whilst in flight.
Common hawker (Aeshna juncea) / Irish damselfly (Coenagrion lunulatum) at Montiaghs Moss
From water to air
Dragonflies and damselflies are usually seen near freshwater habitats like ponds, lakes or streams. This is because most of the life-cycle of odonate species is spent in water. The adults are relatively short-lived: two to four weeks for damselflies and around two months for dragonflies, but it can take from one year up to five years for the nymphs in the water to complete their development. Once this has happened, the nymphs will move to the shore and climb the stems and leaves of tall aquatic plants prior to emergence of the adult insect. If you have the chance to look closely at a pond frequented by dragonflies, you might find a very delicate nymphal cast called the exuvia. These are very useful indicators while surveying for dragonflies and damselflies. If you want to learn more about the life-cycle of aquatic invertebrates, I will refer you to the excellent blog here by fellow trainee ecologist Genevieve Dalley in RSPB Scotland.
Newly emerged four-spotted chasers, with the exuvia. In the bottom picture, it looks like it’s holding its case, and one of the wings still has to unfold.
I find the behaviour of dragonflies and damselflies fascinating to watch. It’s best on a warm sunny day which fortunately happened quite often this summer. It’s a very colourful show of blue and red damselflies flying among the vegetation while golden looking chasers are usually skimming low across the open water. Perched on the tips of emergent rushes and reeds, darter dragonflies are on the lookout to chase intruders of the same species as most male dragonflies are fiercely territorial. You can’t miss the sound of rustling of wings when they are in physical contact.
Top: Male common darter (Sympetrum striolatum) Bottom: Female black darter (Sympetrum danae)
Another great spectacle to watch is the egg laying process, especially when it happens under the water! I was lucky enough to see this recently on a trip to Peatlands Park. Two emerald damselflies walk backwards down an emergent stem to lay eggs until the female is completely submerged. The female at the bottom can trap a bubble of air between its wings so she can still breathe and remain under water for up to 30 minutes!
Emerald damselflies laying eggs underwater. You can see the female completely submerged in the bottom picture.
Some of our species of dragonflies and damselflies will still be on the wing until the end of September into early October, so get out there or you might have to wait another seven months for the show to be on air again!
With its spirals of small white flowers resembling the braided hair of a beautiful maiden, the Irish Lady’s Tresses orchid is one of Northern Ireland’s most eye-catching and rarest plants.
The species was first scientifically described by a botanist on an expedition to islands off Alaska in the early 1800s and there are a number of theories as to how the plant may have made its way to our shores.
The seeds are tiny and lightweight so might have been blown across the Atlantic or they could have been transported on the feet or feathers of birds blown off course on migration.
Until this summer, the wet grassland along the western shore of Lough Beg near Toomebridge was one of just a handful of sites in Northern Ireland where the orchid grows.
However, when out surveying at our Portmore Lough reserve near Aghalee in late July, trainee ecologist Anne Guichard was delighted to spot a single orchid in the area known as the ‘hare field’.
Since then, Irish Lady’s Tresses have been blooming in large numbers at both Lough Beg and Portmore, with more than 400 ‘spikes’ recorded to date across both sites.
Irish Lady’s Tresses flourish on wet, grazed meadows which regularly flood, making Portmore Lough and Lough Beg the perfect places to take root.
Portmore Lough warden Amy Burns says: “We were thrilled find this beautiful plant on our site and it just reaffirms that all the management we undertake here benefits a variety of wildlife and plant life. “Irish Lady’s Tresses are a UK priority species and Northern Ireland has about one-third of the total UK population so it’s vital that the places where the orchid is found are protected.”
Irish Lady’s Tresses are in flower until the end of August so you’d better be quick if you want to spot this stunning species!
Whenever I see a white-coloured butterfly fly past, I ask myself a very simple question to help ID the fluttery fellow - ‘Is he wearing his stripy pyjamas?’
Don’t worry, I haven’t gone stir crazy in the heat! I picked up this very helpful tip (designed for kids but very useful for all Lepidoptera novices) from Catherine Bertrand at Butterfly Conservation when she was at our Portmore Lough reserve last weekend.
As well as getting outside and enjoying the lovely weather we’ve been having in past few days, I’ve also been feeling rather smug at now being able to tell the green veined whites (which have stripy wings) from the stripe-less small and large whites!
Photo credit Andy Hay (rspb-images.com)
There are almost 60 different types of butterfly in the UK and around half of that number can be spotted in our gardens.
They range from the rather unassuming, like the brown ringlet, to the gloriously coloured like the common blue.
Photo credit Ron Surgenor
Of course, as well as being a delight to look at, butterflies play an important role in our ecosystems, including providing pollination and natural pest control.
They are also an important element of the food chain and are prey for birds, bats and other insectivorous animals.
Sadly, butterflies are under threat today from unprecedented environmental change. Their fragility makes them quick to react to change so their struggle to survive is a serious warning about our environment.
The good news is that there are small things we can all do to help give butterflies a home.
Try to plant plenty of different nectar plants that flower throughout spring, summer and autumn, in a sheltered, sunny spot.
You can also leave a 'wild area' of your lawn or plant some attractive wild plants, such as scabious and valerian. Don’t forget to include caterpillar food plants if you want butterflies to breed in your garden.
Some adult butterflies hibernate, so provide places for them to hide – like a hedge or ivy on a fence – and you may see early spring butterflies in your garden like this gorgeous peacock :)
Photo credit Grahame Madge (rspb-images.com)
Don't forget you can take part in Butterfly Conservation’s Big Butterfly Count until 10 August – visit www.bigbutterflycount.org to download an ID sheet and get recording!