Gray Whales and Tsunamis
by Dr. David Rugh

Dr. David Rugh

"With the tsunami, are the whales okay?" This question came to Journey north from a 4th grader. We asked gray whale expert Dr. David Rugh for his thoughts:

Possible Impact
"Without documentation, I'm left to speculate, and perhaps anyone else who thinks about the affect of a tsunami on whales can only speculate too. My first thought is that whales will be almost unaffected. At sea they will have the sensation of a wave passing when the tsunami goes by, much as vessels at sea do, without any deleterious affect. The place where there might be a problem would be near shore when a tsunami rapidly pulls water out to sea before a wave hits the shore. Whales might be stranded for a moment and then pushed hard against tidal rocks as the tsunami overwhelms them. Therefore, the degree of impact may be a function of proximity to the coast. In the days following a tsunami, there might be an increase in strandings of marine mammals if the wave was deadly. Otherwise, most marine mammals will probably go about their business unaffected.

More About Tsunamis
"Tsunamis have different sizes and dynamics, so they will not be consistent
in how they impact the environment. Sometimes a tsunami is first evident by
a large draw-down of water followed by a series of huge waves; sometimes
there is no draw-down at all — that is, almost no warning. The topography of coastal areas makes a big difference as to how these waves behave near
shore. This inconsistency makes it harder to generalize about impact. Videos of tsunamis sometimes show a beach becoming exposed for a short while, and then a high wave comes in. If a whale was very near the beach at that moment, it might be pulled out to sea or — for a few tens of seconds — it might be stranded. It's the force of the incoming wave that could be especially hard on living things. What I imagine could be done for
documenting what a tsunami does to whales is to maintain beach watches,
recording dead cetaceans — not a very sophisticated plan, but at least that record could indicate increased deaths following a tsunami."

A Complex Process
It is unfortunate that the only way to get documentation would mean more
tsunamis and so many other things that we don't plan ahead for or think
about. But study and documentation are necessary before conclusions can be made. Study and documentation take time. Sometimes we turn up new information that changes "old" answers. We are always learning!


Journal or Discussion Questions:
  • We always expect scientists to know all the answers. But answers have to come from someplace. What is one question for which you've never received an answer that satisfies you? Do you think there is just one answer to your particular question? Explain.
  • When an event like this occurs, how does it remind us that ALL living things are connected? How are the impacts of natural disasters or weather events felt around the world in these modern times?