Borth Bog - Field Trip 28th October 2014

Mke Bailey, Natural Resources Wales
(photo by Helen Campbell)

A two hour drive from Bangor took us to another spectacular field site. Located north of Aberystwyth, Borth Bog was our final destination and well worth the drive.

The Bangor University Wetland Science and Conservation class were joined on our field trip by Mike Bailey from Natural Resources Wales (previously Countryside Council for Wales). His knowledge of the area was impressive and gave us an amazing insight into this fascinating area.


Weather: Overcast becoming very wet during the second half of the day.


Site History:

Location of Borth Bog near the village of Borth
(image from Google Maps)

Location of Borth Bog
near Aberystwyth
(image from Google Maps)

Borth Bog is a raised bog within Cors Fochno which is a component part of the Dyfi National Nature Reserve and is managed by Natural Resources Wales.


Cors Fochno is the largest area of undamaged raised mire in Wales (see Wales Wildlife for more information).



The area has been through many transitions since the Last Glacial Maximum. As the ice sheet which covered most of the UK retreated, large amounts of sand and gravel were deposited into the valley.

Salt marsh developed which was succeeded by reed swamp conditions as sand dune systems developed and cut the area off from tidal reach, transitioning into more freshwater habitat.

There is evidence in the stratigraphic record of roots and stumps of trees indicating that the area was forested for around 500 years.

The area then reverted back to a reed swamp most likely due to shifts in climate.

As sphagnum species took hold of the area the reed swamp transitioned into what is now a prime example of a raised peat bog with 7m of peat accumulated over the past 5000 years.


Field Sampling

As wetland scientists we are fascinated by what is going on under the top 5cm of soil.

At this site we took 10 peat samples each, across 2 locations within the bog. The samples were collected using the same techniques used in our previous field trip to Cors Erddreiniog.

Further analysis of these samples will be conducted back in the laboratory.

Otter run between two drainage channels.
(Photo by Helen Campbell)

Observations:

The diversity of habitat structures in this area provides a wide variety of niches for many different species. Birds, insects, amphibians and reptiles and mammals are frequently found here.

We observed an "otter run" between two channels of open water. The otters use the area to clean off and refresh themselves after hunting and fishing in the brackish waters closer to the sea.

Drier, upland areas dominated by tree and shrub species create a habitat matrix within the nature reserve area. (Photo by Helen Campbell)

Areas of open water (Photo by Helen Campbell)

Teal (Anas creeca), Redshank (Tringa totanus), and Water rail (Rallus aquaticus) are common year-round residents. Sedge warblers (Acrocephauls schoenobaenus), Reed warblers (Acrocephauls scirpaceus) and Nightjars (Caprimulgus europaeus) can all be spotted during the summer.

Due to heavy rain on the day of our site visit we didn't observe very much in the way of wildlife, except some rather bedraggled and damp looking Welsh mountain ponies!


Management:

There is plenty of evidence at Borth Bog of the types of strategies required to effectively manage a site of this kind.

Boardwalks, signposts, gates and fences are all useful devices to help keep the public safe and protect the sensitive areas of the bog.

Board walk leading visitors on a pleasant walk through the bog.
(Photo by Helen Campbell)

Restoration and creation of new shallow pools within the bog.
(Photo by Helen Campbell)

A section of newly acquired land needed significant work done to enhance it and restore it back to a more natural wetland.

Drains were blocked helping to retain water on the land for longer after periods of rainfall. Rhododendron and woody scrubby species were controlled and removed from the site to allow grasses, sphagnum and other wetland species to dominate. Shallow pools were created by removing the surface vegetation.

After only a relatively short period of time, this restored area has become well established and requires little maintenance.