Stranded Mandurah female dolphin Zetta dies, new calf born to Willow

"It was a pretty crazy day," says Estuary Guardian Mandurah member Natalie Goddard, and it all began when one of Mandurah's female dolphins was discovered stranded.

Natalie was one of the volunteers who bravely fought to save one of Mandurah's female dolphins on January 31, when she was discovered by another member stranded and in terrible condition miles from anywhere.

As luck would have it, members of many of Mandurah's environmental and wildlife groups were out walking the estuary shoreline as part of the annual Shorebird Count.

It was one of these volunteers, Glenn Moore, who stumbled upon the stranded Zetta and raised the alarm.

"I got the call at 9am from Glenn. He said she was severely sunburned and didn't look well," Natalie recalled.

"We were near the end of the count so we made a plan to get out and go to the place where the dolphin was, between Austin Bay and Boggy Bay which is so extremely remote.

"We went in two groups, with one lot taking a boat and then trudging through wetlands for over an hour with the rescue gear. I came by land with another member.

"It was a good two or three kilometre walk in the hot sun - felt like being in the desert. I've never done a rescue so tough."

Once there, the would-be rescuers realised from her condition that Zetta had probably been stranded the day before, which had been around a 35-degree day. She had severe burns and blistering and was only in ankle deep warm water, which meant she couldn't regulate her temperature.

The team went straight to work trying to bring her temperature down, shading her and keeping her wet.

"We contacted Parks and Wildlife, who have to give permission for any dolphin to be moved and once that came through we got her onto a flotation device and took her into deeper water to see if she was strong enough to swim," Natalie said.

"But the heat had taken its toll and she was too weak.

"She passed away on the device."

As distressing as this was, the team took comfort in the fact she didn't die alone.

"If we hadn't been there she would have suffered a slow death in the sun. At least she died in a bit more comfort," Natalie reflected. "It was amazing luck anyone was even in the area to find her."

The passing of Zetta, who was a successful breeder, is a blow to the breeding stock of Mandurah dolphins, with another female, named 22, missing and River still entangled in line, which can't be removed.

"Too many of these sad events can affect our future population and be catastrophic for Mandurah's dolphins," Natalie said.

Zetta was taken to Murdoch University for an autopsy, with the generous help of Brendon Watts from Wattsies Place, who used his boat to transport her.

But as with everything in nature, things seem to find a way of balancing themselves out.

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On the same morning, long-term volunteer Barbara Sing was out doing a bird count and spotted Willow, another of Mandurah's female dolphins, in town waters with a tiny newborn calf.

"It was only a day or so old. We can tell from the fetal folds the calves have from being inside their mothers and the way they move when they're first born," Natalie explained.

"Willow is a first-time mum so it's really exciting for us. We'll be very observant of her to make sure she's getting used to being a mother but we're hoping she will go very well. In fact, she's been spotted a couple of times since then and seems to be doing great."

Of course the little one will need a name.

However, the usual method of having a competition for community members to name the calf will be different this time around.

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"Sometimes, when it's a particularly special birth, we give the honour to a specific person," Natalie said. "This time we've asked Barbara who first sighted the baby to do the naming. It's particularly special because of the Shorebird Count and the whole circumstances surrounding the birth."

Natalie also wanted to remind people how important it was to report injured, stranded or deceased dolphins.

If you see a stranded dolphin: