What’s the first animal that comes to mind when you think of New England’s ocean? Cod? Striped bass? Maybe great white sharks? For me, lately, it’s been the biggest of all the animals that have ever existed – the blue whale. Bigger than any dinosaur that ever pounded the planet or huge ancient shark* that patrolled the warm, primordial sea, their tongues alone weigh as much as an elephant. These leviathans can weigh over 300,000 pounds. You could swim through their heart (but please don’t try).
We may not see them very often, but these endangered animals cruise by here pretty regularly. Why? They take advantage of our very productive waters to fatten up on tiny shrimp-like krill for their long migration from near the poles toward the equator.
Like some of our other, more frequently encountered leviathans, the North Atlantic right whales, blue whales head south for the winter to have their huge babies, but there’s not enough to eat down there (why do you think the water is so clear?), so they head back up when the calves are ready to travel.
Let’s talk about those huge calves for a minute. They measure over 20 feet long, drink about 150 gallons of milk each day from a mother who is on a diet (due to the poor feeding options in the warm calving grounds), and they double in length within 6 months.
Blue whales’ ears make a long, candle-stick shaped plug of wax throughout the whales lifetime (see below). Scientist are unsure of its function – it might help the whale hear better by channeling the low frequency noises they communicate with to the eardrum.
The wax has “rings” like a tree trunk. There are darker colored rings when the whale is migrating and eating very little, and lighter colored ones when the whale is feasting. This can give scientists big clues about the age of the animal when they harvest the wax from already dead animals. Already pretty interesting, right? But when two scientists at Baylor University recently dug into the biochemistry of the earplug – a novel picture started to emerge.
The wax carries a chemical record of the whale’s life, arranged by year. Hormones produced in the whale’s body are archived in the wax. So the researchers were able to put together never-before recorded pattern of yearly reproductive development and production of stress hormones. Not only that, but pollutants like mercury and pesticides can also be detected in the earplug, giving researchers an idea of what year the whale was exposed to them.
“You have this 100-year-old question: How are we impacting these animals? There is ship traffic, environmental noise, climate change and contaminants. Now, we are able to provide definitive answers by analyzing whale earwax plugs,” said Dr. Sascha Usenko, one of the scientists who developed this technique.
The best part – while the science being used to study the ear wax is new, scientists have been collecting the ear plugs for decades from animals that have been found all over the world. So, knowing the date an animal was found and its age, researchers can figure out what kinds of chemicals the animal was exposed to and possibly link this to our activities on land (for example, increased coal burning or pesticide use), helping us piece together just how much we’re changing this big pond of ours. And, hopefully, we can think even more about how to stop dumping so much ick into our air and water.
Whatever we decide to do with the knowledge – this is a huge new story about the ocean just waiting to be told, from the whales’ ears to ours.
* Please note: megalodons are very extinct, regardless of the Discovery Channels claims to the contrary.