Whatever it is that's making birds get sick and die at a Winnipeg retention pond seems to have spread to a second city pond, says the group working to rescue the ill-fated waterfowl.

Residents in Winnipeg's Mandalay West neighbourhood started finding dead birds and fish in the pond in Santa Fe Park at the corner of Dr. Jose Rizal Way and Adsum Drive in mid-August.

Since then, volunteers with Wildlife Haven Rehabilitation Centre have been taking in and working to rehabilitate sick birds found at the pond.

On Sunday the group told CBC News they've brought in 10 new birds in the last two days, and half of those came from a pond on Lakebourn Drive, a couple of blocks away from the first pond.

A dead bird washes up on the shore of the retention pond in Santa Fe Park on Aug. 23, 2018. (Jeff Stapleton/CBC)

What is causing the die-off remains a mystery.

And that makes it hard to say why sick birds are now showing up another nearby body of water, says Wildlife Haven Rehabilitation Centre executive director Zoé Nakata.

"We're not quite sure, so is one of them a source pond and then it was carried to the other or is it something that has to do with the dry summer that we've had? Are there other ponds in Winnipeg?" she asked Sunday afternoon.

"We don't know, we're kind of just responding to the signs that we're seeing at the moment."

The 10 sick birds recovered so far this weekend brings the total number of birds brought into the the non-profit to more than 30 since mid-August.

This pelican is the only one of 12 birds first rescued from the pond in Santa Fe Park in August to survive. (Submitted/Zoé Nakata)

Of the first 12 birds first recovered by the group, only one — a pelican — survived.

Nakata says the pelican's condition is continuing to to improve and the bird is now eating fish and has been moved to an outdoor facility for further recovery.

She's hopeful it can be released back into the wild soon.

While Nakata doesn't know what's causing the birds to get sick, she says a higher percentage of the latest birds brought in are surviving. She thinks that's because they're being recovered from the water sooner.

"Without knowing exactly what the cause is, it's hard to do a really targeted treatment, but with what we've seen the best treatment is to take them out of the toxic area and into care quickly," she said.

"We're getting better at being proactive and we're succeeding in saving some of these birds."

This duck is one of several birds recovering at Wildlife Haven Rehabilitation Centre. (Submitted/Zoé Nakata)

The group has teams of volunteers checking both ponds daily, and Nakata is asking anyone who finds a sick bird in or around ponds across the city to contact the rescue at 204-878-3740.

"We need eyes on our ponds," she said.

Meanwhile the City of Winnipeg and the province are having dead birds from the Santa Fe Park pond tested. Results of those tests have yet to come back, a Manitoba Sustainable Development spokesperson said last week.

The province has previously said the cause of the deaths could be toxic algae or avian botulism, the latter a disease that can paralyze and kill large numbers of birds. Botulism outbreaks occur naturally in ponds, particularly at this time of year, according to a provincial spokesperson.

The province and city is urging people to avoid contact with the water, keep pets away and avoid touching dead birds.

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