Agrotis infusa Click to enlarge image
Adult Bogong Moth, Agrotis infusa Image: R.Jessop
© Australian Museum

Fast Facts

  • Classification
    Species
    infusa
    Genus
    Agrotis
    Subfamily
    Noctuinae
    Family
    Noctuidae
    Super Family
    Noctuoidea
    Order
    Lepidoptera
    Class
    Insecta
    Subphylum
    Uniramia
    Phylum
    Arthopoda
    Kingdom
    Animalia
  • Size Range
    5 cm

Introduction

Bogong Moths belong to the Family Noctuidae and are well known in south-eastern Australia for their mass migration in spring. In some years, they have descended upon cities such as Sydney and Canberra in their thousands, causing disruption around outdoor sports grounds and to air-conditioning plants.

Identification

The Bogong Moth is native to Australia. The common name comes from Bogong High Plains region in the Victorian Alps, which is one of the sites where the adult moths congregate in huge numbers over the summer months.

Habitat

Bogong Moths live in urban areas, forests and woodlands.

Distribution

Bogong Mouths are found in southern Australia, including Tasmania. Occasionally found in New Zealand and Norfolk Island.



Seasonality

During winter, Bogongs feed inland as black cutworms on seedlings of wide-leafed plants in an area ranging from southern Queensland to South Australia. During spring, they fly south to south-eastwards, to high altitude regions in the southern part of the Dividing Range, where they remain inactive (aestivation) throughout the summer months. They are sometimes blown towards the coast by westerly winds and may enter houses as they are attracted to light. Over summer, adults congregate in rock crevices in massive numbers and remain dormant, living off their fat reserves. They then migrate north to breed as their larvae can't tolerate cold conditions.

Feeding and diet

The larvae of Bogong Moths ("black cutworms") feed on seedlings of wide-leafed plants in inland regions of Australia.

Conservation status

Recently concern has mounted about arsenic levels in the Bogong Moths. The arsenic is present at low levels in the soil of their larval pasturelands and is stored in the body of the adult moth. When the moths die off in their caves, the arsenic leaches from their bodies into the local soil. The arsenic becomes concentrated because of the build-up of dead moths on the floor of the cave over many years. The arsenic could potentially adversely affect their predators, including the Mountain Pygmy Possum, but this has not yet been fully demonstrated.

Economic impacts

Aborigines had a good knowledge and understanding of the habits of the Bogong Moth. They roasted the highly nutritious moths in hot ashes and mashed the bodies to make 'moth meat', which is said to have a nutty taste. The mountain caves where the adults aestivate were known to Aboriginal people, who used the moths as an important source of protein.

Caterpillars of the Bogong Moth are known as cutworms and are considered an agricultural pest, causing significant damage to crops.