Fen Management Handbook - Scottish Natural Heritage

2.6 Amphibians
Amphibians are dependent on open water for breeding and frequently forage in
associated wetlands. All of the widespread native amphibians can be found on
fens: common frog (Rana temporaria), common toad (Bufo bufo), smooth newt
(Lissotriton vulgaris), palmate newt (L. helveticus) and great crested newt (Triturus
cristatus). Only common frog and smooth newt are found in Northern Ireland. Other
rarer amphibians such as the natterjack toad (Bufo calamita) and the reintroduced
population of pool frog (Pelophylax lessonae) in Norfolk do not occur in fen
habitats. Amphibians do not depend on fen sites per se, but frequently forage
in fen vegetation, which provides suitable foraging and hibernation sites (see
Appendix III, Table 3).
Female great crested
newt basking on a log in
fen vegetation (RSPB).
A mass of frog spawn is
not uncommon on fens.
Amphibians often thrive in
ditches and isolated pools
where there is a reduced
presence of fish predators
during the breeding season.
(A. McBride).
Amphibians which are relatively widespread, such as common frog, may not be
considered as conservation priorities in their own right, but their importance as a
food source for a wide range of predators such as bittern or grass snake, may be
influential in determining appropriate management.
2.7 Fish
Fish found in open water associated with fens (see Appendix III Table 4) are also
important food sources for a number of species of conservation concern including
otter and bittern, which may justify targeting of management action for the benefit of
fish.
Native fish species likely to occur in association with fens include roach (Rutilus
rutilus), pike (Esox lucius), common bream (Abramis brama) and the three-spined
stickleback (Gasterosteus aculeatus). These species are typical of lowland rivers,
drains, slow flowing and still open water with low oxygen concentrations.
31