Members of the public have been asked to "keep their eyes peeled" around Strangford Lough after a mother and calf were rescued from a sandbank.
The alarm was raised at the north side of the Lough on Thursday morning.
While the duo were safely returned to the water, there "is a chance" they could end up in trouble again.
When Ruby Free and Josh Anderson from the British Divers Marine Life Rescue team arrived at the scene "the mother and calf were in a bad way".
"They had super dry bodies and eyes. Dolphins effectively get very sunburnt when they're not in water," Ruby told UTV.
The rescue effort involved soaking towels to keep the dolphins wet until the tide came in.
"Once in the water, we sat with the dolphins until they had enough depth to swim for themselves," said Ruby.
"When we let go, at first all seemed well, but the immense push of the tide brought them back onto the sandbank time and time again.
"After a while, the mum was able to swim out for herself, but the young calf struggled.
"Seeing the energy being stripped from the calf, we held her for another 15 minutes until she got enough energy to try again.
"We let her go once more and she swam speedily back to her mum.
"Another 10-15 minutes later, the pair were reunited and back out in deeper water and swam off together.
"We hope they find their way to the seam from here and make a speedy recovery from their small injuries (a few scratches to the body)."
The worry however is that as the rescue happened to the north of the Lough, they may get not find they way to sea straight away.
Ruby said it's "unusual" to see a mother and calf away from a pod.
"We'd appeal to people to keep their eyes peeled," she said.
"If you see them in trouble, please get in touch with British Divers Marine Life Rescue.
"The problem with rescuing wildlife such as whales or dolphins is that they're really powerful so don't get too close.
"The best thing you can do is call the team, on 01825 765536 and they'll immediately send a local team to the scene."
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