A two-month-old dolphin calf is now free from entanglement after a huge effort from DBCA rangers and volunteers.
The dolphin, named Koa, was spotted with a net wrapped around its body several times and through its mouth in the Mandurah area recently.
Efforts to disentangle the young dolphin proved difficult as its mother, Anna, was very protective.
"Together with the rangers, Dr Krista Nicholson and our amazing volunteer group assisting in searches, efforts have continued to try to safely disentangle Koa," Estuary Guardians Mandurah posted on social media.
"It is impossible to explain or understand how difficult this actually is, until you are faced with the situation.
"Dolphins are highly mobile animals in a marine environment, are very protective mothers, coupled with variable weather conditions, and highly stretched resources.
"With a gentle guiding tail movement, mother Anna was able to ensure Koa was just out of reach, not understanding we were all there to safely help."
At last the netting began to break and loosen with volunteers spotting Koa on Monday with no visible entanglement.
The local volunteer group is urging people to dispose of their rubbish properly.
"What this calf endured was human caused," Estuary Guardians Mandurah said.
"It highlights we all MUST increase efforts to keep our waterways clean.
"Please join in with any community clean ups, stop and pick up any loose fishing line, rope, netting and litter you see, fish responsibly, and slow down and go around our dolphins!"
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