Platypus are mainly nocturnal and crepuscular (active at night, dawn and dusk) but can occasionally be observed during daylight hours on cooler days. They are particularly active during winter and early spring when females feed frequently to build up fat reserves in preparation for breeding and egg laying.
Sensitive to sudden noise, vibrations and movements, this secretive animal usually disappears at the first sight or sound of disturbance. On our excursions, we regularly have excellent views of this shy and elusive animal and have often observed interesting interactions between individuals and with other species.
We have observed animals successfully foraging for small fish in tiny rock pools below a waterfall on the Atherton Tablelands. Up to 3 adult platypus were observed ‘fishing’ regularly in these pools. The fish were trapped in pools about 30 centimetres across and the platypus would sometimes have only to immerse its head and shoulders before grabbing a fish and withdrawing from the pool. The 3-5 centimetre-long fish were still very much alive and wriggling while clamped firmly in the platypus’ bill.
The animal appeared to have problems despatching the fish as many were lost back into the pool. The most successful method employed by the platypus for killing the fish was to grasp the fish firmly in its bill and then to turn its head and bill on its side and then rub the fish (and bill) against the surrounding rock. This affectively injured or immobilized the fish. The platypus then released its grip and ate the fish without losing it back into the pool. Through binoculars it was possible to clearly see tiny silvery fish scales on the rocks that had been used by the platypus as a ‘rubbing stone’. This behaviour was observed from a nearby bridge many times by several of our groups over a period of about three weeks.
Gathering Nest Material
We observed a female one evening collecting and carrying a considerable amount of nesting material rolled-up in her tail. Some of the stems were at least 20 centimetres long and projected either side of the tail. This caused problems when the animal tried to swim. Each time she attempted to dive she popped back to the surface, tail-first like a cork because of the buoyancy of the material.! The entrance to her burrow was about 5-6 centimetres in diameter and about 70 metres from where she had collected the grassy material. It was about 30 centimetres above the level of surface of the water and positioned under a small root. With much wriggling she disappeared inside with the stems still held in her tail. She re-emerged about 30 minutes later and after a grooming session continued collecting more nesting material.
Escaping an Owl
One July evening at dusk while we were with a group on an Atherton Tablelands riverbank, we observed a platypus swimming towards us from downstream in the fast fading light. Quite suddenly a large owl appeared from within the shadows of an overhanging tree and immediately dived at the platypus. Seeing or sensing the danger from above, the animal quickly submerged. The owl struck the surface of the water and then returned to the cover of the overhanging trees. Through binoculars we were able to make out a large Rufous Owl sitting under the canopy on a dead branch about four metres above the river.
Several minutes elapsed before the platypus reappeared a few metres upstream from us. Almost immediately the owl again launched an attack on the platypus which dived with a loud splash. The owl struck the water exactly where the platypus had been a second or so earlier. The Owl recovered from its dunking and flew to another vantage point some 20 metres upstream. By this time the platypus had vanished and the light had faded making further observation impossible. Do Rufous Owls regularly hunt platypus on the Tablelands, or was this just an isolated incident? This large Ninox owl certainly has the equipment to take large and formidable prey as the photo at left will testify!
Eaten by Eagles..?
Another interesting observation was made while searching for animal remains in the pellets discarded from a White-bellied Sea-eagle nest by two well-grown eaglets. Amongst the many terrapin carapaces and waterbird remains we found a partly eaten and desiccated carcass of a platypus. Was this animal caught live by the adult eagles or was it already dead and scavenged by them to feed their young?
Collared by Accident
In September, while watching platypus on the Atherton Tablelands, one of our groups observed an individual with a blue plastic milk bottle ring around its neck like a collar. Obviously distressed, the animal was having difficulty swallowing. We notified the Environmental Protection Agency about this unfortunate animal.