Dugong numbers on the rise in Hervey Bay, but concerns remain

Researchers have expressed cautious optimism about the growth of dugong populations in key coastal areas of south-east Queensland.

A recent study conducted by James Cook University (JCU) researchers in collaboration with TropWATER, released last month, reported positive population growth and a wider geographic spread of dugongs in Hervey Bay and the Great Sandy Strait. This is attributed to the revival of seagrass habitats in these areas following major flooding in 2022 that decimated seagrass meadows.

Positive signs of growth but concerns remain

The study used aerial surveys to analyse the recovery of the vulnerable species. According to the report, researchers initially counted about 109 dugongs in 2024 — a slight increase on the 103 dugongs noted in 2022. The distribution of dugongs also changed, with the marine mammals mainly spotted in the central portion off Hervey Bay in 2022, but had spread south towards the Great Sandy Strait in 2024.

Christophe Cleguer, a principal research officer at JCU, said, "Typically these surveys tend to happen every five years, so it was great to see the [federal] government provide funding to do another survey so soon."

The researchers used two data-collection methods to calculate the dugong population: raw counts and abundance estimation. Cleguer explained that correction factors are applied because "there's a good chance if they're feeding at the bottom, or if the water is too deep and murky, you'll miss them."

Low number of calves raises concerns

However, the low number of calves has raised concerns about whether the local population is truly on the path to recovery. Only three calves were tallied in 2024, a decrease from the nine spotted in 2022. Cleguer said, "There is a time lag for dugongs; they need to recover and get healthy enough to reproduce calves." He added that further monitoring was needed to determine how nutritional stress was impacting their reproductive responses.

Simon Miller, Great Barrier Reef campaign manager for the Australian Marine Conservation Society, said the report was an "important" measure for the local dugong population. He expressed concerns about the few calves, saying, "We're not seeing any evidence a lot of dugongs are coming back."

Future collaboration and monitoring

JCU hopes to secure funding to conduct a third aerial survey into the dugong population stretching from the southern Great Barrier Reef to Moreton Bay next year. Cleguer said collaborating with local organisations would be "beneficial" as they could survey using drones or vessels to give an indication of dugong presence and movement.

Shawn Wondunna-Foley, chair of the Butchulla Native Title Aboriginal Corporation, highlighted the importance of protecting seagrass and dugongs, saying, "When we look after the seagrass, we look after the yuangan, and we look after sea country."

Miller encouraged people to make a difference by respecting slow zones and being aware of their surroundings to protect the incredible wildlife.