Fen Management Handbook - Scottish Natural Heritage

Encroaching and overhanging vegetation should be cut back periodically around breeding ponds to
prevent them from becoming shaded. However, some marginal shading vegetation can be important
to provide shelter for emerging froglets, so avoid clearing the entirety of a pond margin in one
management operation.
Sensitive periods
Young froglets are at risk of trampling when they emerge from the pond, so management around and
of breeding ponds should take place after metamorphosis but before the first frosts.
Common Toad
Common toads have more specific habitat requirements than the common frog. Preferred habitats
are rough grassland, scrub and open woodland, and within these areas, large permanent water
bodies are generally required. Optimum pond size is around 1000 m2, with a good cover of
emergent and submerged vegetation. Common toad tadpoles are not eaten by fish owing to the
presence of toxins in the skin. They seem to prefer ponds containing fish as breeding sites, which
may be attributable to the lack of competition from frogs.
General management and sensitive periods are as listed above for common frog. Also, toad
migration to breeding sites in early spring can exceed distances of 1000m, and there is the
possibility of road casualties if site access roads form a barrier along migration routes. Consider
installation of amphibian tunnels under access roads in such situations.
Pool Frog
As a general rule pool frogs prefer small to middle sized ponds and avoid lakes. The optimum depth
for these ponds is 1-1.5 m with a suitable input/water table whereby water levels are maintained
through the spring and summer (to September) for successful breeding. Pool frog tadpoles are
distasteful to fish such as sticklebacks, but predation of adults by large fish is thought to affect the
pattern of population variation between ponds in Sweden. Ponds should therefore be monitored for
fish presence, with fish removed if colonisation occurs. Clusters of ponds should be provided within
200-600 m of each other, linked by suitable terrestrial habitat. Female pool frogs often gather in a
separate pond before transferring to the breeding pond. Ponds should have clear access to southfacing
banks for sunning.
Pond vegetation structure should be a mosaic of open water, submergent, emergent, and marginal
species. Pool frogs lay their eggs in clumps at pond surface near perimeter shallows or more
centrally on rafts of vegetation which allow a warmer micro-environment. Regular management of
invasive species such as bulrush is recommended to prevent ponds from becoming choked with
vegetation.
Trees should not shade the pond area, although pool frogs can often be found in woodland margin
ponds. Proximity of woodland offers easy access to suitable terrestrial habitat for foraging, feeding
and hibernation. Pool frogs hibernate on land and require suitable frost-free cavities in ground
debris, holes, log piles, tree stumps, mossy clumps etc. for hibernation 100-300 m from pond.
Hibernation sites can be created relatively quickly and cheaply from part-buried rubble mounds
or log piles situated near to ponds in areas free from flood risk. Ideally, terrestrial habitat should
include woodland with moist understory with low-growing vegetation, rougher, tussocky sections in
grassland areas. Occasional wet ditches are also beneficial.
It is advisable to have as wide a buffer zone as possible between the pond and any agricultural land.
If a grazing management regime is used then a low density of cattle is preferred, which should be
monitored regularly by the use of static position photographs to avoid overgrazing.
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