Authorities are continuing an urgent search for a baby less than one year old after the bodies of a mother and her toddler were recovered from the ocean near Port MacDonnell in South Australia.

Police received a call about an abandoned car, found with its engine still running near Cape Northumberland on Monday morning. Officers later discovered the bodies of a woman and a small child in the water below rugged cliffs. The deceased have been identified as a 36-year-old woman from Compton, near Mount Gambier, and her toddler.

Search efforts involving the Water Operations Unit, Country Fire Service, and State Emergency Service volunteers, alongside local fishing crews, were underway on Monday until darkness halted operations. Detectives from the Major Crime Investigation Branch and specialist forensic officers are attending the scene.

Superintendent Trent Cox expressed grave concerns for the baby's safety, stating that given the circumstances, the child's ability to survive if in the water is a significant worry. While authorities are keeping an open mind, Cox noted that hope for the baby's survival is not high.

Adverse weather is predicted to potentially impede water-based search efforts on Tuesday. However, police plan to continue searching the coastline on foot and utilize thermal imaging drones. The search area includes the waters off Port MacDonnell.

Police are appealing for information from the public. They are particularly interested in anyone who may have seen the woman's vehicle, a white 2015 Isuzu MUX with South Australian registration S592BJR, or who may have dashcam footage of the area. This information is being sought to help investigators piece together the woman's movements leading up to her arrival at Cape Northumberland.

The rugged coastline near Port MacDonnell where the bodies were found.