What do whales do when a storm of historic proportion hits their coast?
WDC’s North American office is located in Plymouth, MA, one of the communities hard hit by this week’s blizzard-hurricane, named Juno. With nearly three feet (1M) of snow falling within 24 hours and accompanied by hurricane force winds, Massachusetts issued a travel ban to reduce the risk of human casualties and enable the state’s cleaning crews to clear roads.
The NA office fared well with only a short power loss, banged up signage, and four foot snow drifts to dig through. While the office was closed for a couple of days as a result (sorry if you called or emailed during the closure- we will get back to you!), did you ever wonder what the whales were doing during this blizza-cane?
Truth be told, we’re not exactly sure but here are some things to consider.
- Whales are generally sparse during winter in New England. Most large whales are migratory and move south to mate and calve. It’s not that whales can’t survive here in the winter, as some do hang around, but small schooling fish are scarce during the winter so there’s little point of being here. Most of the “whale action” is happening in temperate and tropical waters south of here. We don’t know where all whales go, but we do know that humpback whales from the North Atlantic mate and calve in the West Indies, and North Atlantic right whales give birth off the southeast US (between North Carolina and Florida.
- It’s warmer out there than it is here, at least during storms! While we stayed indoors to avoid the freeze as wind chills dipped to -5F (-20C) during the storm, the water temps in Cape Cod Bay hovered around 39F (4C). For our primary winter resident whales, North Atlantic right whales, these water temps are downright comfortable.
- Sing a song? Researchers can’t risk life and limb to watch what whales do in rough seas but there are some data to indicate that life is pretty normal for whales, even if it’s not for us. In 2006, WHOI researcher Mark Baumgartner deployed underwater gliders off Cape Cod as a major Nor’easter was about to hit. Dropped in 17 foot (5m) seas, the researchers retreated before the storm worsened. The gliders remained throughout the storm and recorded calls from humpback, sei, and North Atlantic right whales!
- Run away! It’s not unprecedented that after major summer storms, whales in coastal areas scatter for a bit following the storm. The saying that “still waters run deep” could be modified to deep waters run more still, or still-ish. Storms tend to churn up the surface but have limited impact at depth. Of course, depth is all relative. At its deepest, Cape Cod Bay reaches 206 feet (63m), only four body lengths for a right whale, or comparable to you being in a little over 20 feet (6m) of water- not so deep. In these shallow waters, rough seas and high winds can literally stir up the ocean and mix thermoclines (temperature layers), changing water temperatures and salinities up to 300 feet below the surface. While the direct effect on whales is not known, these turbulent waters do impact critters like copepods, the primary prey item for right whales. These tiny little zooplankton concentrate based on internal waves and currents. When dispersed, they are of little value to these hungry whales. For the whales, leaving may be a good choice both for comfort and for finding food.
- Be prepared. There is also some evidence that non-human animals can detect and respond to pressure changes well before us humans. Reports of animals retreating to higher ground before natural disasters are universal. Some dogs respond to barometric pressure changes well before we humans hear that first clap of thunder. So it’s also possible that whales can either sense the pressure changes, or note the signs, and react, before the storms “hit”.
With two more storms threatening coastal Massachusetts in the coming days, our NA office staff is not relying on sensing pressure changes to react, but is monitoring the forecast closely and remains in storm preparedness mode. When the wind and waves calm down, we’ll head out to some of our favorite viewing spots to see if our backyard neighbors, critically endangered North Atlantic right whales, ventured back into Cape Cod Bay for their plankton picnic.