The forty-spotted pardalote (Pardalotus quadragintus) is an endangered songbird found only in Tasmania. It used to be widespread across the island’s forests where its preferred food tree, the white gum, occurs. This tiny bird now survives in small, fragmented populations and is one of Australia’s most endangered birds.
Why is it in trouble?
Habitat loss and degradation
Deforestation and degradation of old-growth forests has reduced tree hollow numbers that are essential for nesting.
Nest competition
Hollows are often taken by more common species like striated pardalotes and tree martins.
Parasitic fly
Native parasitic flies threaten nestlings and reduce their survival rate.
Why is it difficult?
They are extremely small
Forty-spotted pardalotes are smaller than a matchbox and easy to miss.
They live high in the canopy
They nest in tiny tree hollows high in white gum trees, making nests hard to find and monitor.
They are quiet and elusive
Their soft calls are difficult to hear, even when nearby.
What we are doing?
Research and Monitoring
Since 2010, we have monitored forty-spotted pardalotes across their entire remaining range, including Bruny, Maria and Flinders islands. This work tracks population size and distribution, identifies important habitat, and has already led to the discovery of a new population, which is a major conservation success.
Parasitic Flies
The forty-spotted pardalote is losing most of its chicks to a tiny parasitic fly,Passeromyia longicornis. This fly lays eggs in the birds’ nests, and the larvae feed on the chicks, causing very high death rates. To help, we developed a simple but powerful tool: feather dispensers filled with insecticide-treated feathers. The birds collect these feathers for their nests, and the treatment protects their young. We are now rolling out feather dispensers across North Bruny Island.
What next?
To understand the parasite, we need to catch it. We are now running the first-ever tests to trap adult flies. This will help us learn how the parasite lives and how to control it in the long term.
