What a remarkable way to welcome the Northern Residents back to these waters! The season’s first calls echoing through Blackfish Sound came faintly just before 12:30am, much to the joy of those at our lab and dedicated volunteers listening from around the globe. We hope it marks the beginning of what we have come to know so well: days possessed by the movements of orcas through these waters.
The initial excitement came after becoming aware of dolphin calls, with the identification of A5 calls carrying that distinctive “A4ish flare” – the telltale signature of the A42s travelling with A94 “Mystery”. But there were other A4 calls in the mix, too. Perhaps daylight would bring clarity.
It was one of the most beautiful starts to a season, with nearly 90 minutes of active, mellifluous orca calls and lots of echolocation until 2am, unencumbered by any other noise. As their blows reached Blackney Pass, audible in the darkness from the lab deck, a tug came into the passage from the south, followed by a “pack” of vessels that would sadly mask the orca calls for the next hour. As the orcas travelled south in Blackney Passage, all we heard was boat noise.
The whales finally broke their silence at 3:18am. By now they were near Cracroft Point in Johnstone Strait, the A4 group closer with the A5s further east across the Strait. A humpback also made their presence known not far away. Sadly, the boat noise continued, but the whales left a trail of acoustic breadcrumbs east into Robson Bight, where they foraged for a while around 4am. By 5am, the leading A42s had made it to Strider Rubbing Beach, and – although our hydrophone is currently not working – keen-eyed viewers caught a glimpse of their fins in the very early dawn. They did not stick around at the beach for long, continuing east and out of our range.
True to form, the North Island community rallied and by 10am, we heard a report of 5 Northern Residents – the A64s with A78 – heading west in Johnstone Strait, near Swaine Point on the Cracroft shore. Ah-ha! Those A4 calls had indeed belonged to another matriline, the A24 group, and they had said goodbye to the easting A5s in the early dawn. Through the morning, they slowly made their way towards Cracroft Point and, at 1pm, eventually travelling as a tight group towards the entrance of Blackney Pass. Here, they foraged for a while before eventually travelling casually west along the Hanson Island shore.
The A64s and A78 took Weynton Passage north in the afternoon, and were off Donegal Head heading northwest by 5pm. We had heard them as they crossed Blackfish Sound, not making headway too quickly, making the last calls audible to us shortly after 7pm. As the evening drew on, it was a question as to whether they would aturn back with the flooding current, or whether they would head “out” perhaps, hopefully, to pick up some more matrilines! But it had been a lovely example of how these groups coordinate their movement while accompanying each other on their journeys.
Elsewhere, humpbacks Ripple, Argonaut, Squall and Quartz kept us busy from the lab deck throughout the day, alongside a large group of Pacific white-sided dolphins around 6pm. The summer is well and truly here, and we are excited to share it with you!
