Indo-Pacific bottlenose dolphins in the Gold Coast
Indo-Pacific bottlenose dolphins are the most frequently seen species in the Gold Coast region. The population appears to be fragmented, with some communities preferring to remain in certain areas of the coast and others near estuarine waters.
Along the coastal zone, hotspots of Indo-Pacific bottlenose dolphins exist around the Currumbin Creek, Durranbar and Jumpinpin. At this stage, we have been unable to accurately estimate the abundance of dolphins that use the open coastal habitats.
Our research has focused on the resident community of bottlenose dolphins that frequent the Broadwater. From our early surveys, we estimate that this community consisted of around 17 individuals (95% CI 22.31 – 31.42) in 2010-2011. Using data from citizen science records, a student from Griffith University, recently confirmed that some of the individuals in this southern resident community have been in the region for at least 30 years. Our recent surveys confirm that many of the adults seen in 2010 and 2011 are still in the region.
The majority of individuals within the southern bottlenose dolphin community are females, however, we know that at least one male alliance is also part of this community. The females in this community are very tightly bonded. Calves can be born throughout the year, but we do find a peak in births during the warmer months of late summer through to autumn. The community regularly forages and feeds throughout the Broadwater region. At times, females from this community they can be seen foraging up to 15km up the Nerang or Coomera Rivers chasing prey.
From analysing the scarring patterns and injuries on the southern resident dolphins, we know that the majority of this community have scars from shark bites, entanglements in fishing gear and boat strikes. Their reliance on the Broadwater region which is also one of the busiest for human activities in the Gold Coast region, makes this community highly vulnerable. We are continuing to work on understanding the health of the southern resident dolphin community.
Our surveys are currently focusing on this community of resident dolphins to determine their status, health and habitat use as part of our Healthy Waterways-Healthy Dolphins Project.