Signs of Orca predating on Humpback calves was witnessed today with a young 2023 Humpback calf swimming with Mum very close to our vessel today. Approaching very slowly to within a few hundred meters the mother whale beelined our vessel and swam within our ‘sound footprint’ very wary of the surrounding environment. It wasn’t too long when the calf came close enough to show the common Orca rake marks from their teeth around the dorsal area and plenty of barnacle scars from where mum hashed the little one in contact with the barnacles on her body while trying to keep the calf away from Orca. The Orca attempt to grab the dorsal and use their powerful tail pressure to roll the calf over not allowing it to breathe and drowning the calf, this way they can consume mainly the tongue and lips of the Humpback calf, thankfully though Mum has done her job and protected her baby so he lives to swim further south.
Part of our collaboration research is with CETREC, John Totterdell’s research team which spends many days on the North West Cape researching the predation on the Humpback Calves as they move southbound, John advises they can lose up to 200 calves a year to Orca (Killer Whale) predation. We also have Killer Whales sighted and ID’d around Rottnest Island and today the long downtime and limited surface language let us know that they could be quite near the vicinity as they were sighted last week off the Windmills of Rottnest Island when we had similar behaviour. We had another vessel approach the nervous mother and calf which caused her to move within just a couple of meters as she looked for the protection of our sound footprint from the intruding vessel that arrived at speed. We gently moved away and she returned to her long downtime as the intruding vessel drove around trying to find her again without success.
The afternoon tour started very similar and we did again have our mother and calf approach but we had spent some time with her so decided to look further out and we were welcomed into a pod of 4 adult Humpbacks that were socialising and inspecting our vessel as they approached very closely under our bow and stern, again another vessel rudely interrupted at speed and one of the Humpback Whales launched into a series of tail lobs to deter the fast moving vessel which eventually departed after getting their Facebook shots. After they left we had some spy hopping as the Humpbacks were checking us out from above and below the water to the delight of our guests. We spend endless hours with the whales in Perth and it is disappointing some recreational boats do not abide by the rules around whales, it is of even greater disappointment when it is another eco tour operator who should know better but obviously not in this case, regardless the whales always win as they will leave vessels that do not show them respect and everyone must take a moment to understand the enormity of what these wonderful creatures go through on a yearly basis just to survive.
Thankfully all ended well today and we had a happy pod of adults moving south and mum and calf showed us some breaching as we were on the return to port completing another special day.
