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Butterfly Predators
Common Toad
Bufo bufo
LINNAEUS, 1758
Family - BUFONIDAE
Sometimes a butterfly photography
trip draws a complete blank, as happened to me on a trip to Stockbridge
Down in April 2008. Blackthorn blossom was in bloom and
there was a profusion of violets, ground ivy and other nectar
sources in flower, but overcast weather and a cold breeze precluded butterfly activity. Not to be outdone, I searched
for other subjects, and came across several Common Toads,
including this mating pair, enjoying a mud bath.
Toads spend the early stages of
their development under water in ponds, ditches or large puddles,
but once full grown they live entirely on land, and spend the
daylight hours hidden away in holes amongst tree roots or under
hedges.
At dusk they emerge to feed on small
mobile prey including worms, beetles, woodlice, slugs, snails and
caterpillars. They feed voraciously, consuming hundreds of
insects in a single meal, and are major predators of nocturnal
grass-feeding caterpillars including Satyrines ( Meadow Browns,
Ringlets, Gatekeepers etc ) and Hesperiines ( Skippers ).
Common Toads enter hibernation in October and re-awaken in
February or March of the following year. Both sexes then migrate
over a period of several days until they find their original birth
place - usually a deep pond or ditch.
During the migration the males mount the females, which carry them
to the pond, where they swim about until the female locates a
water plant. There she lays a long glutinous string of up to 7000
eggs which become entangled around the plant. The male fertilises
them as they are laid.
After about a
week, the developing young can be distinguished within the eggs.
Two weeks later they wriggle free from the surrounding
jelly, becoming free-swimming tadpoles. During the early stages of
development the tadpoles feed on algae.
As they grow larger, the
limbs develop and the tadpole takes on the appearance of a
miniature toad. By this time it has changed it's feeding habits,
moving from algae to plankton, and later to small crustaceans and
invertebrates.
Toads secrete a
toxic substance which protects them against certain predators, but
crows and herons learn to disembowel them. Their greatest natural
enemies are flies - the greenbottle fly
Lucilia caesar lays it's eggs on the toads body, and
the grubs crawl into the toad's nostrils, causing it great
distress. Soon afterwards they begin to eat the eyes and brain,
slowly killing the toad, and then consume the remaining flesh to
leave just the skin and skeleton.
Toads which are
lucky enough to escape this ghastly death can live for up to 10
years, but large numbers are killed by cars during their
migrations. In many areas of Britain conservation groups fix
temporary barriers by roadsides to divert the animals, or
construct tunnels beneath roads so they can cross safely.
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