BATTLE: In the fen corner Cors Erddreiniog and in the bog corner Migneint

So, along with a group of Bangor University undergraduates we visited two different sites with aims to see the difference between them both.

The first site we visited was Cors Erddreiniog which we previously visited during the LIFE conference a blog on which can be found here.

This time however we had to get our hands dirty! We started the day with some talks, then split into groups to measure diversity using quadrats, plunge sticks to measure peat depth and measuring pH and conductivity of the soil with special appliances.

The Migneint is the second site we visited, it is the largest area of  blanket bog in the UK and is situated in central Snowdonia. It is a Special Area of Conservation (SAC) and work has been carried out to help restore it since large areas have been damaged by ongoing afforestaion, drainage, grazing and also burning, in hopes to make it better for agriculture. Being an important breeding ground for Hen Harriers it is in the interest of many to bring the area back to its full potential including the RSPCA who have been undertaking many projects which can be found here. An interesting article and video can be found on the BBC website giving an insight into the conservation efforts of the site.

Peat erosion complex at the Migneint

At the Migneint there were strange peat erosion complexes, these are where the peat has been degraded possibly due to the previous drainage issues at the site meaning the peat gets an influx of oxygen which increases degradation. These complexes show how deep the peat could have been if the site was left in its natural state. 

Differences

The main visual difference when comparing the two sites is definitely the height of the vegetation.Walking along the boardwalks at Cors Erddreiniog you are surrounded by vegetation almost at eye level, whereas at the Migneint the vegetation is almost all low lying comprising mainly of mosses and Juncus. The main reasoning for this could be that the water supply for blanket bogs is nutrient poor as it all comes from precipitation in comparison to the Cors Erddreiniog fen which is fed by a mixture of rain water and groundwater increasing nutrient levels and improving primary production. Conductivity was much higher at the fen and pH was recorded to be close to neutral, due to the calcium ions increasing the pH compared to the lower pH of the Migneint and also the lower conductivity.

Image showing some peat cuttings in the background

Life Conference: Cors Geirch

I did not attend the trip to Cors Geirch, but that doesn't mean it's not an important wetland in the North Wales area. This site is situated on the Llyn Peninsula in a valley that lies between Pwllheli and Nefyn. Much like the other sites visited during the LIFE conference the reserve is recognized as a SSSI, SAC and also protected by RAMAR.

Map of Llyn Peninsula showing Cors Geirch

It is another fen site that is fed by alkaline water that drains into through the surrounding porous limestone rock making it a rare type of wetland. The site is also managed by CCW, and Welsh Mountain ponies are used to graze the site.
The site is special as it was the first in Wales to have the rare Narrow-leaved Marsh Orchid identified in 1953, it has now been identified at Cors Bodeilio and Cors Erddeiniog.
Many fenland species which were also see the at other sites we visited were present at Cors Geirch which can be seen listed on the Countryside Council for Wales website.
In the early 90s the site went through a large scale restoration project removing the top 30cm of peat across a large area of the site. The results included a raised water table and reduced fertility, allowing fen plant species to recolonise where agricultural species once dominated. More information on peat re profiling can be found on the LIFE project website.

Life Conference: Cors Bodeilio

Boardwalk at Cors Bodeilio made from recycled plastic

After a free lunch of local meat burgers and delicious cake arranged by the LIFE project at Cors Erddreiniog we hopped back on the mini bus and traveled to Cors Bodeilio. The site lies in a shallow valley between Llangefni and Pentraeth. The water that feeds the fen comes down through the surrounding Carboniferous limestone rock, this water is what makes the underlying mire so special. With a variety of wetland fen species many of these being quite rare and only found at a few sites in the UK the reserve is within a designated SSSI, is also a RAMSAR site and is also a SAC.

Some of the ponies that graze the site

In the past the calcium rich water was diverted away from the fen resulting in the site becoming derelict. However, with various management strategies by CCW the site has returned to its former glory. An adjustable u-bend pipe system has been created to adjust the water level of the fen. During heavy ra

infall (pretty much all the time in wales!!) the pipe can be lowered to lower the water level at the site and also helps prevent flooding in neighbouring fields.
The site is grazed with Welsh Mountain ponies to ensure that natural fen vegetation can thrive, if the site was not grazed a thick thatch of the sedge Cladium mariscus would form taking nutrients and preventing light penetrating lower canopies.

Wildlife

Succisa pratensis also known as Devils-bit can be found at the site

The fen provides a habitat for many species such as great fen sedge and bottle brush sedge. It is also home to some rarer species including the dwarf stonewort and the Fly Orchid. Invertebrates thrive at the site such as dragon flies and grasshopper warblers and also the the medicinal leech. There are two pairs of Lapwings at the site and is also one of two sites on Anglesey where Snipe can be found. A list of other plants and animals which inhabit the site can be found here.

Life Conference: Cors Erddreiniog

Cors Erddreiniog is the largest of the Anglesey fens covering 289ha thus making access to the site quite difficult unless you can speak the secret language of 'farmer'. Luckily, the project had a few translators on hand.

The large site is lime rich and made up of a mixture of habitats, similar to Cors Goch it was formed by the terrestrialisation of Llyn yr Wyth - a glacial lake. The centre of the site is comprised of calcareous fen with areas of alkaline fen and both wet and dry heathland around the edges. Being such a rare type of wetland the site is protected by RAMSAR and is recognised as a SSSI and also a SAC.

Redirected spring water

For many years the site was used for agriculture and many ditches had been dug to drain the land, this along with the use of fertilizers had drastically reduced biodiversity at the site. Management of the site has improved the quality of the fen, by filling in drainage ditches and the with use of a piston bully, the site is now know as "Jewel in the crown of Anglesey fens".

The piston bully was used to remove vast amounts of "improved soils". These are soils which have been heavily fertilized and are not suitable for peat producing species to colonise. The LIFE project removed the soil and exposed the white marl that lay beneath the top layers, by diverting the spring waters hydrological pathways to what they would have naturally been, a new lease of life was given to the site. Seeing natural colonisation of many wetland loving species.

Constructed wetland in the foreground
natural wetland in background

The water to the fen is fed by limestone 3 springs and before it reaches its destination some of the spring water passes through a specifically constructed wetland. The constructed wetland is used as a treatment area to denitrify the spring water utilising denitrifying bacteria. The water that enters the wetland has been contaminated with N from the fertilizers of the farms surrounding the site. The constructed wetland was colonised naturally with species such as Stonewort. Some spring water is also passed through a mixing chamber which also removes excess N. The denitrifyed water can then spread over travel down to the site, specific fen species such as M15 and M19 have a higher chance of establishing in the areas where N has been removed from the water. The communities of these species developed over 5 years which is surprisingly fast compared to other less well managed sites.

To keep the fen in prime condition grazing is carried out by some dairy cattle of  the local farmers. However the dairy cattle cannot be kept here for a long period of time because of the poor nutrient content of the grazing. The LIFE project introduced Konic and Welsh Mountain Ponies onto the site during the times when cattle grazing is not suitable. Grazing is a key part in the management of the site, it prevents build-up of a thick thatch of vegetation which prevents light penetrating through to establishing plant species. In more sensitive parts of the site local contractors are hired to strim cut the vegetation.

Wildlife
There is a rich variety of wildlife found at Cors Erddreiniog. I will list some below..

• Great fen sedge
• Blunt-flowered rush
• Black bog rush
• Columbine
• Grass-of-Parnassus
• Sphagnum moss
• Cross leaved heath
• Marsh gentian

Bog stars also known as Grass of Parnassus

The site is special to contain many species of orchid that cannot be found anywhere else in Britain other than a few sites on Anglesey and the Llyn Peninsula. These include

• Northern marsh orchid
• Fen orchid
• Marsh helleborine
• Fly orchid

Insect life is rife at the reserve, the marsh fritillary, one of Britains most threatened butterflies can be found here along with species of dragonfly and damselfly, including the rare southern damselfly. With insects usually comes birds, the fen attracts a variety of bird life with winter bringing hunting hen harriers and lapwings to the site and with the arrival of summer sees birds such as the willow tit and grass-hopper warblers arriving at the reserve. There are also many other animals at the site, so eyes should be kept peeled for toads, adders, otters, brown hare and water voles.

Life Conference: Cors Goch

Day 1 of the Life Conference starts at the amazing Plas Menai in Caernarfon. The first thing to do upon arrival is to get myself a cup of tea, and a question pops into my head... does being a wetlander always require such early mornings?
After an interesting morning of talks from many people who work with the Life Project (and plenty more cups of tea) it was time for lunch, then a short coach trip to the first site...

Cors Goch

The site is owned and managed by the North Wales Wildlife Trust, and is a Site of Special Scientific Interest (SSSI) protected under the RAMSAR convention.

Cors Goch is a beautiful patchwork of wetland, heath, meadow and rocky outcrops making it home to a huge variety of species. The wetland at the site is characterised as calcareous fen land, as the supply of water to the fen is calcium rich due to the surrounding limestone rock. The underlying the drier heathland at the site is sandstone rock making it more acidic than the lowland fen.

Looking down at Cors Goch from surrounding limestone

The site was formed thousands of years ago when glacial movement created a basin where a lake once lay. The land surrounding the lake was then colonised by vegetation, which naturally, over time began to decompose and form peat. As the peat continued to accumulate the area of which the lake covered began to decrease until eventually it was filled, which is what we can see at the site today.

Wildlife
Plant species are in abundance at the fen site and include Great pond sedge, Bottle brush sedge, Common Reed, Black bog rush, Blunt-flowered rush and the carnivorous Butterwort, but don't worry it doesn't eat humans (I hope).
The drier heathland areas are inhabited by Hawthorn, Blackthorn and also to the despair of the site manager Bracken which is slowly encroaching down toward the fen.
These plants all provide cover for many vertebrates including numerous species of bird such as Sedge Warblers, Hen Harrier and also the Yellowhammer. Other vertebrates include Foxes and Stoats. The fen site which is supplied by calcium rich water that supplies the fen allows it to become is a perfect environment for a host of invertebrates including species of Frog and Toad, both Palmate and Crested newt species have been spotted at the site. There are species of Dragonfly's and Damselfly's, and the Medicinal Leech inhabits the waterlogged areas of the site.

Becoming a Wetlander

If you asked me a month ago what a wetland was the only word that would've popped into my head would've been swamp. But NO wetlands come in many varieties.... who'd have known?

Identifying a wetland is not as simple as it might seem. When a botanist wants to identify a plant there are various keys that can be used to differentiate between plants, but a key for identifying wetland types? Don't be ridiculous. Even the definitions are pretty vague.

The Ramsar Convention defines a wetland as...
"Areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six meters"

That makes things a lot clearer doesn't it? Yep, didn't think so.

The best way for me to get my head round the many different types of wetlands is to experience them first hand.

My first experience of a wetland was at the Life Conference at Plas Menai. Over the 3 day conference we visited CORS GOCH, CORS ERDDREINIOG, CORS BODEILIO and CORS GEIRCH (Handy tip: WEAR WELLIES).