Australian Humpback Dolphin

The Australian humpback dolphin is a medium-sized marine mammal recognizable by the distinctive fatty hump beneath its dorsal fin, which becomes more pronounced with age. Adults are typically grey, often with lighter mottling on the underside, and can reach lengths of around 2.7 meters. They live in small, fluid social groups, feeding on coastal fish and cephalopods using echolocation, and are frequently seen in shallow, turbid waters close to shore.

As a mid-level marine predator, the species contributes to the regulation of fish populations in coastal and estuarine ecosystems.

Its range spans the tropical and subtropical waters of northern Australia and southern Papua New Guinea, encompassing marine neritic and oceanic zones as well as coastal, supratidal, and adjoining freshwater habitats such as permanent rivers and estuaries. This reliance on nearshore environments places the species in close proximity to expanding human activity.

The species faces a wide range of ongoing pressures, including habitat loss and degradation from coastal urban and industrial development, aquaculture, mining, and agriculture. Shipping traffic and associated noise, light, and thermal pollution disturb critical habitat, while entanglement in fishing gear and bycatch from fisheries pose direct mortality risks. Invasive species and broader ecosystem modifications, including habitat shifting linked to environmental change, further compound these pressures.

Conservation efforts include habitat protection within marine protected areas, fisheries bycatch mitigation measures, and ongoing population monitoring and research to clarify distribution and abundance. Precise population figures remain limited.

Given the breadth and persistence of threats across its coastal range, the population is assessed as decreasing, and long-term recovery will depend on sustained management of coastal development and fisheries interactions.