SnotBot Expedition IV, Mexico 2017: How big are blue whales?

To describe the size of different objects, we often make comparisons to various everyday items such as school buses or an Olympic sized swimming pool. When the objects we refer to reach a certain size, it can be difficult for us to truly comprehend just how large they are, and we switch off, no longer able to visualize them effectively.

Animals, for the most part, our well within our boundaries of comprehension. An elephant is an enormous animal, yet it is not so different from our own size that we cannot process and understand it.

When we get to the large whales, we begin to cross this boundary. The largest whales of all are difficult to visualize and the comparisons we use become extreme. Blue whales are animals made for superlatives. They are the largest animals ever to have existed on our planet; 99% of species which have ever lived on our planet have gone extinct. How fortunate we are to live at the same time as these great leviathans.

This latest SnotBot expedition has focused upon these enormous animals. I am fortunate enough to have seen most of the great whales, yet this expedition is my first time seeing blue whales, and they truly dwarf any other whales in both length and sheer size/weight. I’m going to throw out a few size comparisons; try to visualize, try to comprehend, the scale of these animals.

 

A blue whale’s tongue can weigh as much as an adult elephant. ITS TONGUE. Try to picture a tongue the size of an elephant.

Adult blue whales need to eat around 8,000 pounds of food per day. That is the weight equivalent of 60 average-sized humans. Every day… They are of course not eating humans, but tiny shrimp-like organisms called krill; 8,000 pounds of krill = 40 million individual krill.

They can grow to 100 feet in length. I still struggle to comprehend this, but it really struck home with me on our first day out on the water with the whales. A blue whale lunged out of the water. It lunged directly away from us, yet its head was only 25 feet away from us. This means that some of its body must have been UNDERNEATH our boat. We estimated the whale was 80 feet long. If it surfaced 25 feet from our boat, and our boat was about 10 feet long, this means that the whale’s tail/fluke would have been about 45 feet on the other side of our boat.

Here is another fact: The global population of blue whales, decimated by 20th century whaling, is currently estimated to be roughly around 7% of its pre-whaling population, around 15,000 animals. Try and comprehend that; 15,000 animals representing an entire species. The largest species which has ever existed on planet earth. Many modern sports stadiums can hold 4 or 5 times this number of people. My university had more students than the entire global population of blue whales.

SnotBot is a tool which can help us understand these animals, and other endangered whales, in order that we can better protect them — and they desperately need our protection. There are many species or sub-populations of whale on the verge of extinction: The Baiji or Chinese river dolphin has already gone extinct. The Vaquita porpoise of the Sea of Cortez looks set to follow (sorry to be blunt, but it’s true). Maui’s dolphin is not far behind. The North Pacific right whale population is estimated to be around 30 individuals, Western Pacific gray whales under 150, Okhotsk Sea bowhead whales and Arabian Sea humpback whales under 100, Gulf of Mexico Bryde’s whale under 40. The largest pre-whaling blue whale population, in the Southern Ocean, is around 1% of its pre-whaling levels. This is a depressing fact: over 30 years after the cessation of commercial whaling, this population has shown few signs of recovery.

SnotBot is a tool which can collect a wide array of data. Thus far we have used SnotBot to collect blow samples, photo-ID, photogrammetry, bio-acoustics, lowlight/night-time studies, behavioural data and bio-kinetics data. Undoubtedly there are many applications of this technology we have not thought of. A tool which can simultaneously collect so many forms of data is rare. But one which can do so economically (our favoured drone, the DJI Mavic PRO, costs under $1,000) is revolutionary. The cheaper the tool, the more groups around the world can use it in their own research/conservation programs to collect all this different data. And with these streams of data being collected all around the world, scientists and conservationists can begin to take great steps forward in our ability to understand and ultimately protect, these animals.

— Andy Rogan

 

This work was made possible by generous support of the Waitt Foundation through a Rapid Ocean Conservation grant. It is a privilege to be supported by such a prestigious foundation, whose mission is to Restore Our Oceans to Full Productivity.