For the past two weeks, whenever the weather has allowed, I have been out by Bold Head (at the eastern end of Queen Charlotte Strait) collecting data on humpback whales. This area is transformed at this time of year… earlier in the season, it was not unusual to see 1 or 2 humpback whales around Bold Head; while on August 22nd, we counted 17 individuals in this one area. With the help of many volunteers, including Annika Putt, Caitlin Birdsall, Erica Forssman, Tyson Hopkins, and Nic Dedeluk, I have been filming bait balls underwater and measuring herring for my thesis research (see previous blog post for details). I have also been doing focal follows of humpback whales (I will explain more about this in a future post), and identifying which whales are spending time feeding in the area.
Two of the whales that we have seen almost every day around Bold Head are “Slash” (BCY0177) and her calf, “Stitch”. Slash’s nickname comes from the parallel scars across her back. In 2006, she was photographed by MERS director Jared Towers with deep, recent, unhealed injuries on her back. The injuries indicated that Slash was the victim of a vessel strike; these parallel cuts were caused by a boat propeller. Vessel strikes are becoming a serious concern for humpback whales around Vancouver Island (see this blog post by the BC Cetacean Sightings Network for more details).
Fortunately, Slash survived her injuries, and has returned to the northeastern Vancouver Island area every year since 2006. In 2008, she brought her first documented calf to the area, a whale that we nick-named “Moonstar” based on the markings that look like a moon and a star on her tail. Moonstar has also been seen in the area every year since she was born.
This year, Slash returned to the area with a new calf, who was recently nicknamed “Stitch” by children from the Gwa’sala-’Nakwaxda’xw summer day camp from nearby Port Hardy. Humpback whale calves nurse for about a year, and therefore maintain very close bonds with their mothers during this time. However, it is also very important that the mothers get enough food during the summer to provide them with the energy that they need to nurse their calves, and to migrate back to winter breeding grounds in Hawaii or Mexico. During the past couple of weeks, we have seen Slash leave her calf’s side, in order to feed on the dense schools of herring that are found in the area. Without her mother at her side, the calf often becomes very active at the surface… breaching, rolling around, and playing in kelp!
Once BCY0177 has finished feeding, she communicates with her calf underwater, using grunting sounds that likely alert her calf to where she is… stay tuned, we’ll post these sounds soon!