Led by the NSW Department of Climate Change, Energy, the Environment and Water and funded by the NSW Environmental Trust, The Great Big Little Penguin Count is part of the broader Seabirds to Seascapes (S2S) program.
A pilot study ran in 2022, followed by official counts in 2023 and 2024. A final count under the S2S program is scheduled for 2025. The following summary outlines the preliminary results and findings from The Great Big Little Penguin Count interim report 2024.
What we’ve found so far
Early results show that little penguin numbers in New South Wales are trending down. Similar results have been observed in other parts of southern and western Australia. While Victoria’s Phillip Island colony has grown in recent years, many NSW colonies are declining, particularly on larger islands such as Barunguba Montague Island and Bowen Island.
Smaller island colonies have generally seen smaller or less consistent declines. More data is needed from the 2025 count to confirm long-term trends.
Barunguba Montague and Bowen Islands show significant decline
Comparisons to earlier studies indicate little penguin populations on Barunguba Montague Island have likely been in decline for decades. This project has used 2 different survey methods there, and both show a significant drop in the number of penguins breeding on the island.
Bowen Island is showing a similar pattern. Compared to studies from the 1990s, current penguin numbers are dramatically lower.
What's causing the decline?
The reasons for these declines vary by location, but some consistent challenges are emerging:
- Habitat degradation: On islands such as Barunguba Montague and Bowen, penguin nesting areas are being choked by invasive weeds. This reduces the amount of suitable habitat for breeding.
- Oceanic conditions: In 2024, breeding started later than usual, and many chicks were underweight or didn’t survive. Changes in ocean currents, temperatures and food availability are likely contributors. These factors can vary locally or affect large areas of the NSW coast.
- Predators on the mainland: On the mainland, the Manly colony is under threat from foxes. However, this threat is being managed by the NSW National Parks and Wildlife Service, Northern Beaches Council and local volunteers.
How we count little penguins
To estimate little penguin populations, scientists used a mix of survey methods, including direct observation and landing counts (watching penguins come ashore at night). On Barunguba Montague Island, it’s become clear that traditional ‘transect’ surveys (sampling narrow strips of land) are no longer effective. With so few penguins nesting, this method often misses them entirely.
Future surveys will rely more on landing counts, which are proving to be a more accurate and reliable way to track penguin numbers.
What’s next for 2025
In the final year of the S2S program, surveys will focus on key islands that were once strongholds for little penguins. These locations include Manly in Sydney Harbour and the following islands: Barunguba Montague, Bowen, Brush, Lion, Wasp, Belowla and Snapper. This updated data will help confirm the scale of changes we’re seeing.
We’ll also continue monitoring the endangered Manly population to understand how it's responding to ongoing management efforts.
Where we need to focus
The interim report recommends the following actions.
1. Improving penguin habitat
- Map weed infestations on key breeding islands to secure funding for gradual weed control and long-term habitat restoration.
- Support follow-up efforts to ensure restored areas stay healthy, providing better nesting habitat that allows penguins to breed safely and successfully.
2. Researching the marine environment
- Study ocean currents and temperatures near breeding colonies to track changes in prey availability and food quality.
- Investigate interactions with New Zealand fur seals, whose numbers are growing in NSW waters, to understand the conditions penguins face at sea. This knowledge will help us assess their health on land.
3. Enhancing tools and monitoring
- Introduce automated nest-box tracking to collect data on penguin behaviour and breeding effort.
- Continue long-term monitoring to establish strong datasets for each colony, essential for tracking shifts in survival and breeding patterns over time.
Limitations and learnings
There are limits to how precise these population estimates can be. Not every penguin returns to shore on the night of a count, and we can’t see inside every burrow to confirm breeding activity. Some landing sites on islands are also hard to access or observe.
Still, the methods used represent the best approach currently available. With careful planning, the 2025 season will build on what we’ve learned and help strengthen confidence in long-term trends.
Why the Great Big Little Penguin Count matters
This project has exposed a critical knowledge gap about little penguins in New South Wales. While much is known about penguins in Victoria and other states, we still have limited information about the breeding and foraging habits of our local populations. There is even less information on their current productivity and how they are affected by, and are responding to, potential threats such as changes in sea surface temperatures and ocean currents in New South Wales.
The Great Big Little Penguin Count is a crucial step towards filling that gap. By building a statewide picture, we can make more informed decisions to help protect little penguins now and into the future.
The road ahead
The Seabirds to Seascapes program has laid important foundations in monitoring the little penguin population in New South Wales, but regular monitoring must continue. Looking ahead, the report strongly recommends focusing on these key areas:
- understanding factors affecting breeding success and survival
- studying artificial nest sites and their role in conservation
- expanding knowledge of marine impacts such as ocean warming, prey shifts, and predation.