Recent Mother and Calf Pairs in Rarotonga - The Center for Cetacean Research and Conservation

31 August 2020

Whale season has suddenly picked up over the past couple of weeks! After a slow start to the season, we can hardly go anywhere without seeing whales anymore!

On Saturday, August 22nd, Nan, Stan, and Katie spent the whole day driving around the island looking for whales from shore, since the sea ended up being rougher than expected. The whales tend to stick close to the reef in Rarotonga, so it’s not hard to spot them from land! We received reports from Mark and Shannon Harris in the afternoon of a mother and calf off their house in Arorangi. The calf was tail slapping repeatedly, and they could easily hear it from shore! As the mother and calf began traveling anticlockwise around the island, we caught up with them by Arorangi Wharf.

This was a beautiful, light-colored calf with a very white belly. The calf looked tiny compared to his mother! Nan estimated him to be around 3 weeks old, judging by the frequency of his breaths. He played around on top of his mother, who was carrying him carefully balanced on her head. She hung just below the surface of the water, so her baby could easily go up for a breath and come back down for a rest. The moment became even more beautiful when we noticed a group of spinner dolphins swimming around and bow riding the whales!

The team headed out on the water the next day to try and find this mother and calf again, and we ended up having a very exciting day at sea. After departing the harbour at 9:00, we hardly had a moment without whales! We quickly found a pair of adults just off Vaiana’s Bar & Bistro and an adult and juvenile pair off the Sea Wall, which were reported by fishermen in the morning. After getting some fluke shots and DNA samples from these animals, we continued on, determined to find the mother and calf.

It didn’t take long to spot the gorgeous white baby breaching off Crown Beach Resort! We were thrilled to find this mother and calf again and collect sloughed skin samples from them both. Nan was surprised by this calf’s motor skills at such a young age! He displayed all sorts of surface activity, such as breaching and pec slapping, which was impressive for such a young animal.

We found two more pairs of adult whales before we returned to the harbour, for a total of 10 humpbacks that we saw throughout the day. We only made it a quarter of the way around the island and received reports of 2 whales off Muri Beach (on the opposite side of the island) as we were washing down the boat, so we know that there were at least a couple more out there. It was an exciting, busy day for us! We had beautiful encounters and lots of surface activity, which resulted in one of the biggest pieces of sloughed skin we’ve ever seen! We were very excited to collect that huge piece of skin for DNA analysis.

We had yet another incredible day on the water on Wednesday, August 26^th. The water was unbelievably flat, which made the whales especially easy to spot. We were very happy to find the same light-colored calf breaching off town! This young whale is growing more and more, gaining about a hundred pounds a day from his mother’s milk! The calf did lots of breaching for us, but while his mother slept underwater, the calf stayed close, tucking himself under her chin. Mothers and calves tend to stay close together to appear as one animal, as a way to protect the calf from predators. Though he was careful, this calf was clearly curious! He peeked his head out from underneath his mother to peer up at us.

After leaving this mother and calf, we found so many whales that we had trouble keeping track of them all. We saw at least 11 animals throughout the day. At the end of the day, we were thrilled to find another mother and calf pair off Arorangi! It was easy to tell that this was a different calf because it was very dark in color. While the first calf’s belly was very white, this one’s was entirely black! This mother and calf put on a wonderful show for us, breaching over and over, sometimes simultaneously.

Although you would think that mothers and calf pairs would interact, they are quite solitary, and we have never seen them come together here. How different it is from the behavior of dolphins, who put their babies together in a little nursery pod!