The platypus is the only Australian mammal known to
be venomous. Adult males have a pointed spur (about 15 millimetres long)
located just above the heel of each hind leg, which can be used to inject
poison produced by a gland in the thigh (the crural gland).
Venom is only secreted by mature males, with production
peaking during the platypus breeding season in late winter and spring.
It is therefore presumed that males mainly use their spurs when competing
for mates or breeding territories.
If provoked, a male platypus can use his spurs as a
defensive weapon. In the days when platypus were shot for their fur, dogs
were sometimes killed after being sent to retrieve a wounded male from the
water. These days, people mainly get spurred when they handle a platypus
which has become hooked inadvertently on a fishing line.
Platypus venom is not considered to be life-threatening
to a healthy human. However, spurring is painful - in part, because platypus
spurs are sharp and can be driven in with great force. As well, platypus
poison triggers severe pain in the affected limb and can result in quite
spectacular localised swelling.
No one actually knows how dangerous platypus venom is
to other platypus. In captivity, a 15-year-old male died some days after
being spurred by a younger adult in December (after the breeding season).
However, it remained unclear whether the resulting tissue damage was due
to the effects of poison or simply physical trauma and possible infection.
Platypus should never be handled, except in an emergency
- for example, to extract a fishing hook that has become embedded in a platypus's
bill. In such a situation, the platypus can be restrained by holding its
body flat against the ground while the hook is carefully removed - ideally
by a second person. Special care should be taken to avoid holding or supporting
males (or animals of undetermined sex) from below. If it is necessary to
pick up a sick or injured animal (for example, to place it in a secure bag
or box before taking it to a veterinarian) the safest technique is to grip
the platypus by the middle or end of its tail (but not the tail base, which
an animal can reach with its spurs). To reduce struggling, cover the animal's
eyes with a folded towel or item of soft clothing while it is being handled.
WHAT SHOULD I DO IF SPURRED?
If spurred, take first-aid action as for snake-bite
immobilise the injured
limb with a pressure-bandage and splint;
keep calm and avoid strenuous movement;
seek medical assistance as soon as possible.
The pain appears to be controlled more effectively
by local nerve-blocking agents than by morphine-related drugs. Placing
ice or cold-packs on the site of the spur wound is not advisable as this
may actually intensify the discomfort.