The Common Toad (Bufo bufo)
By Nigel Hand, photos Simon Williams
Common Toads
©Simon
Williams
Most of us must be familiar
with the common toad. I remember a large individual, who
lived in a drainage hole in the back wall of my parent’s
garden; on damp summer nights I would watch it hunting
moths, slugs, worms and spiders. This is one of my earliest
recollections of amphibians, which fuelled my herpetological
passion.
The common toad is the larger of the two toad
species found in the British Isles. The Natterjack (Bufo
calamita)
is restricted to heathland and coastal dunes. There is a
colony in Wales but none in Herefordshire. Common toads are
sparsely distributed throughout Herefordshire, rough
grassland, scrubby open woodland with a nearby pond are
typical habitat. It does not adapt to the small garden as
readily as the common frog, they appear to need larger still
water bodies for spawning.
It is
distributed throughout Europe from Scandinavia through
southern Europe into northwest Africa.
Description
Common Toad
©P.
King
The Common
Toad is warty in appearance, unlike the smooth skinned frog,
grey brown or ruddy brown in overall colour, the belly a dirty
white. It is able to lighten or darken skin tone to suit its
environment.
The eye is coppery red with a horizontal darker
pupil. The two
large glands behind the eyes, known as the
paratoid glands,
contain a noxious secretion that deters predators. A dog
which picks up a toad will salivate and froth at the mouth and
while preoccupied the toad will make its escape. The symptoms
from the toxins are very short term. Females are larger than
males, up to 90mm, males 60mm. They move in a series of short
hops or a crawl.
Life
history
Toads are particular about
their breeding ponds, tending to favour ancestral ponds. Even
when filled in they will return to the former site! The
preference is for larger water bodies.
In late
March to early April damp mild nights see toads travelling
from winter hibernation to their spawning ponds, often in
large numbers. They can travel as far as 1600 meters in a
matter of days. Some males will arrive on the back of a
female, but the tendency is for males to get to the pond
first, calling to attract the females. Balls of male toads
form around single females in a mating frenzy. They will
grasp any moving object presented, such is the desire to
mate. The female will emit a release call if grabbed by a
male after she has finished spawning.
Breeding frenzy
©Simon
Williams
Toad spawn
is laid in strings two rows of eggs in a string of jelly, the
emergent tadpoles are black, frog tadpoles brown. The toad
tadpoles are distasteful to most predators, apart from
dragonfly and water beetle larvae and great crested newts who
have all managed to overcome this.
The tadpoles
will shoal and move to the warm shallows. After 8 to 12 weeks
they emerge as toadlets at 10mm. They then move off en masse
into the cover of long vegetation. The cycle repeats in 3 to
4 years when they reach sexual maturity.
Toads are
long-lived and a captive individual can achieve 36 years. A
wild toad would be lucky to reach 10 years old.
Grass snakes
are able to eat toads and I have witnessed this regularly.
The toad will inflate and stand on tiptoes to look larger and
more intimidating. But neither this nor its toxic secretions will
prevent a grass snake from eating the toad. Also
hedgehogs, buzzards, corvids and herons will all prey on
toads. Otters, mink and polecats will skin them or turn them
onto their bellies to avoid the toxins and eat them.
Common Toad
©Simon
Williams
Conclusion
Toads are declining mainly
through pond losses. Many toads are lost on their spring
migrations when crossing busy roads. In some areas toad breeding
ponds are transected by several roads where mortality rates
will be high. HART needs to know where major toad breeding
sites are within the county in an effort to protect them for
the future. Any information should be passed on to HART.
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