The lager lorikeets: Vets baffled after species of the colourful bird acts like it's had a huge night on the town - followed by a hangover and DEATH

  • Every year red-collared lorikeets in Northern Territory act drunk
  • The colourful birds lose coordination, pass out and sometimes die
  • Veterinarians are baffled by what is causing the mystery illness
  • Previous tests have come back with zero alcohol readings 

Veterinarians in the Northern Territory are baffled as to what is causing a species of lorikeet to act drunk and hungover.

Every year red-collared lorikeets in the territory start acting as if they're on a bender, usually in the build up to wet season.

The birds have been known to lose coordination, pass out and fall out of trees. Some become so unwell they die.

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Red-collared lorikeets in the Northern Territory look 'sick' and 'sad' after a night of drinking

Every year red-collared lorikeets in the Northern Territory act as if they are drunk and hungover

 Lorikeets act 'sloshed' and are sometimes unable to walk or fly after drinking from the tree

The colourful birds have been known to lose coordination, pass out and die from the mystery illness

Darwin animal hospital The Ark has reported a surge in lorikeets brought in for treatment over the past week.

'They are behaving in a way where they cannot control their body [in] a state of drunkenness really, it appears,' vet nurse Mandy Hall told The ABC.

'People are finding them walking around in their gardens and on roads.'

The exact cause of the illness is still unclear.

Previous explanations have included the birds eating fermented fruit or suffering from a seasonal virus.

Ms Hall ruled out alcohol, however, saying previous lab tests had come back with zero readings.

Dr Stephen Cutter, the owner of The Ark animal hospital, told the NT News last year the birds were likely suffering from a combination of factors.

'We still don't know the exact cause — it may be several different diseases working together, definitely some kind of virus that seems to attack the immune system and usually seasonal,' he said.

The Ark will this year send at least nine samples for lab testing to find out the cause of the 'drunk' lorikeets, The ABC reported.

Ms Hall said the results could help treat birds in the future.

 Birds flock to drink fermented nectar from 'the drunken parrot tree' (Weeping Boer-bean tree)

The exact cause of the illness is unclear. Previous explanations have included the birds eating fermented fruit or suffering from a seasonal virus 

 Dr Cutter examines a 'completely sloshed' lorikeet at the Ark Animal Hospital in Darwin, NT

Veterinarians in the Northern Territory are baffled as to what exactly is causing the illness

 Inebriated birds are fed, watered and nursed back to health after drinking fermented nectar

The birds' strange behaviour has traditionally explained as intoxication from eating fermented fruit. However, recent lab tests had come back with zero alcohol readings

 Rainbow lorikeets in Adelaide's Botanic Garden have been getting 'drunk' on fermented nectar

 The red-collared lorikeet is a subspecies of the lorikeet and is found in northern Australia