Although it may not seem optimal, leaky dams have proven to be highly effective in revitalizing dried-up marshes in the West Country of England. These structures create new environments for carnivorous plants and a spider that can quickly catch prey by gliding over the water’s surface.
Porous dams are being built on two mires, Agglestone and Greenlands, in Purbeck, Dorset. These dams are made from bales of heather and bunds made of a combination of peaty soil and timber.
The concept involves obstructing man-made ditches that were originally created to drain marshes for the purpose of growing conifer trees or grazing livestock. This encourages the water to seep out gradually and revitalizes the dried-up wetlands, which are overseen by the National Trust.
According to David Brown, the main ecologist of the charity in Purbeck, this will result in a more diverse environment for plants and animals and also help produce new peat, a valuable storage for carbon.
Brown stated that distributing water evenly throughout the mires would result in a wetter environment, ideal for the growth of mosses and unique species like marsh saxifrage and small bog orchids. The mires in Purbeck are vital for the survival of rare insects, plants, and wildlife, including bog hoverflies and birds like skylarks.
In environments with high acidity and constant water, mosses and other plants are unable to fully decompose. Instead, they gradually transform into fresh peat, which prevents the release of their carbon into the air.
![A rare raft spider on top of floating vegetation in a pond.](https://californiaminorityalliance.com/wp-content/uploads/2024/02/dorsets-bogs-are-being-revived-by-leaky-dams-attracting-floating-spiders-and-plants-that-consume-insects.jpg)
In 2020, a portion of land known as the marshes was recognized as England’s inaugural “super national nature reserve.” This area is made up of a diverse mix of landscapes including heaths, forests, reed beds, salt marshes, dunes, and mires.
The Dorset Peat Partnership project is currently working to improve 16 peaty sites in Dorset, which cover 425 acres (172 hectares) in total and cost £1 million.
The project at Greenlands mire was finished last week and water has already accumulated against the dams, causing it to spread. This week, construction is commencing at Agglestone mire, which is near a stunning attraction known as Agglestone Rock or the Devil’s Anvil.
According to Brown, the creation of a new wetland ecosystem will offer a much-needed refuge for numerous endangered species that have been facing endangerment as a result of the vanishing of these marshy habitats throughout the nation. This includes various types of small animals, such as the rare raft spider, a predatory creature that uses its legs to sense vibrations from potential prey in the boggy pools and swiftly captures them by floating on the surface like a raft.
Birds and mammals are drawn to insects, like the uncommon nightjars that make their home on the heathland and hunt for food above the marshes. Additionally, certain scarce plant species that thrive in the peat bogs also benefit from the presence of insects, particularly carnivorous plants that rely on catching and consuming insects to supplement their diet in the nutrient-deficient bog.
![Bodies of water, trees and bogland.](https://californiaminorityalliance.com/wp-content/uploads/2024/02/dorsets-bogs-are-being-revived-by-leaky-dams-attracting-floating-spiders-and-plants-that-consume-insects-1.jpg)
The Godlingston Sundew, one of the carnivorous plants, was named after its discovery on Godlingston Heath in Purbeck.
Another part of the project includes cutting back invasive purple moor grass, which has thrived in the face of recent droughts and is threatening to smother other more delicate wetland species.
According to Brown, restoring the wetlands will enhance their ability to withstand drought and fires by retaining more water in the environment during the summer. It will also aid in mitigating flooding by absorbing excess rainfall.
The initiative is backed by Natural England’s nature for climate peatland grant program, which provides over £50 million towards peatland restoration initiatives throughout the nation. The British government reports that 87% of England’s peatlands are in a state of decline, harmed, and dehydrated.
Source: theguardian.com