Man-made havens – canals and ditches
Canals and ditches are entirely man-made, yet
they can support a great variety of wildlife. Damage to natural
rivers, lakes and streams has meant that, in many areas, some
species depend on canals and ditches.
Canals were constructed for the bulk movement of cargo, mainly
during the 18th and 19th centuries. In Wales, the canal system is
relatively small, but wildlife has colonised these habitats and
some are now very diverse.
What you can find - The Montgomery Canal in Powys is probably
the most important canal in Britain for wildlife. As well as many
locally rare plants and animals, it has a very large population of
the internationally threatened floating water-plantain and
grasswrack pondweed, which is one of the species included in
Biodiversity Action Plans.
Ditches are generally much smaller than canals, and were
constructed to drain land for agriculture. Many ditch systems drain
large areas of flat land close to sea level, such as the Gwent
Levels or Malltraeth Marsh on Anglesey.
What you can find - These areas are important for water birds.
Ditches often have rare invertebrates such as the rare great silver
water beetle, one of Britain’s largest insects. The Gwent Levels
also has populations of rootless duckweed, the world’s smallest
Both ditches and canals need constant management to prevent them
from becoming clogged with vegetation and silted up.