Tale of a Whale

This morning Donna and Ruth joined Sean, Tom and myself on the Astirix for a dolphin survey in the bay. We departed Moss Landing Harbor and headed north. As we were moving past Pajaro Dunes, Sean and Tom spotted a humpback whale! We drove off shore to get a good look. We got close enough to get some photographs of the tail; individuals can be identified by the coloration patterns on the underside of the fluke. We also attempted to take some biopsy samples. Tom, a researcher for the Southwest Fisheries Science Center and the co-principal investigator for this Earthwatch project, has joined Team 3 in order to take biopsy samples of the bottlenose dolphins that we encounter.

In addition to bottlenose samples, he is also permitted to take biopsy samples of other marine mammals, so we decided to take the opportunity to learn more about this humpback whale. A biopsy sample that includes skin and blubber can be used to determine characteristics such as gender, reproductive health and even toxic levels of an individual. Tom uses a crossbow to fire a dart at the animal. At the end of the dart is a biopsy needle; a metal cylinder about the size of two pencil erasers. This is the part that goes into the animal, and the barbs on the inside of the cylinder catch onto and remove skin and a small piece of blubber. Directly behind the biopsy needle, the dart is covered with foam. This foam acts as a stopper so the needle does not go in too deep and so the dart bounces off of the animal after grabbing the tissue sample. The foam also allows the dart to float in the water for later retrieval by the crew on the boat.

Tom made three attempts at taking a biopsy sample of our humpback whale. It's often a challenge to hit a moving animal from a small moving boat. Unfortunately, all three of Tom's shots were misses. Even though we did not hit the whale with the darts, we still recorded the time of each attempt as well GPS coordinates. We ultimately decided to leave the whale alone because it seemed to be evading the boat.

We continued on our survey and turned around at Manresa Beach. We reached Moss Landing Harbor shortly after 1pm; our first day in the bay that we did not encounter bottlenose dolphins. However, it was still an exciting day!