The Nature Corner: Visitor from the ocean’s depths

Published 8:49 am Saturday, April 11, 2020

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The Coastland Times had articles in its March 8 and 11 issues on a humpback whale that appeared on the beach at Nags Head on March 5. A team of marine biologists investigated, including performing a necropsy, what biologist term an autopsy on wildlife. They were interested in why the whale had beached itself, and what else they could learn about these mysterious leviathans on the deep.

Their study gathered valuable information and left some questions unanswered. The animal had lacerations on its fins indicating that it had been entangled in fishing nets. This might have been the cause of death since whales, like other mammals, need to surface to breath air. Other causes, however, were not ruled out.

Whales beaching themselves is rather rare. The article said that it is the second so far this year on the Outer Banks, and that there had been a total of four last year, more than normal. There are several possible known reasons for these beachings.

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First of all, the animal may die from disease or age or other natural causes and be washed ashore by surf and tides. But the individual whale in question was a juvenile male and as best as could be determined in good health.

There may be human-made causes such as pollutant chemicals in the water, collision with boats, or entanglement in fishing gear. There was some indication that the last of these was involved.

Whales and other cetaceans, an order of mammals including dolphins and orcas, make use of a natural sonar for echolocation and communication. The use of sonar by humans may interfere with that, something like another radio station cutting in on the one you are trying to listen to. For that matter all the racket produced by boat traffic and such may cause interference. If disoriented, a whale might beach itself. Sound travels more than four times faster in water than in air, so whales and other marine animals depend on it more than we commonly know.

Another possibility is the whale was fleeing predators and was in effect chased into shore. This seems rather unlikely, since given the size of whales sharks are generally not a threat. Orcas are more frequent predators, hence their common name “killer whale.” But the ocra’s typical hunting method is to go after the young (calves) by separating them from their mothers.

Are we stumped yet?  I’ll hazard my own hypothesis, but first we need a little more background on whales.

We do not often see whales because they typically occur in our waters only during their spring and fall migration, as they pass by farther off shore.  (In doing our nature documentary series, “Refuge — The Series,” we encountered and filmed a whale [a bowfin as I recall] only once and briefly in the making of the Pea Island National Wildlife Refuge film.)

Besides birds, many other animal species seasonally migrate, including a number of sea turtles and fish species such as salmon, herring, striped bass and shad. Humpback and other whale species migrate from colder northern waters, where food is plentiful in summer, to the Caribbean to mate and bear their young.

If whale migration is similar to bird migration (with which I’m more familiar), the whale in question may well have just been lost and confused, resulting in its beaching itself. Birds from hundreds or even thousands of miles away frequently show up on the Outer Banks, especially in fall and winter. A scissor tail flycatcher, western tanager and western kingbird in recent years come to mind. Their native ranges are all west of the Mississippi River. They are not here as tourists to enjoy our beaches, but lost, blown off course by storms or whatever. The lost birds are typically young birds, attempting their first migration, hence more easily disoriented about directions and destinations. The Coastland Times article states that the beached whale was a juvenile male, which lends some support to my tentative hypothesis. Also we are within the time period for humpback whale spring migration (typically in March and April).

(A brief addendum: Birders get excited about these “lost birds” because they are of course unusual bird sightings. But I always feel a bit sad. These birds will probably never find their way back “home,” to mate with their kind, and so forth. They are rather like runaway teenagers in a faraway strange city, not knowing how to fend for themselves.)

Whales are extraordinary creatures. The blue whale is the largest animal ever to inhabit Earth. It can grow to over 100 feet long and 300,000 pounds, four times heavier than any dinosaur. The humpback whale is what you might call a medium sized whale, growing up to 60 feet and 100,000 pounds.

They are probably the whale species most frequently seen, partly because of their habit of “breaching,” leaping out of the water, arching their backs, then diving. It gives you a chance to get a glimpse of the whale, and by the way, gives it its name. The rising out of the water and bending the back in preparation for a dive accentuated the hump in front of the dorsal fin. I watched humpbacks “breaching” in Alaska’s Glacier Bay some years ago. What a sight.

In the photo in The Coastland Times, you could see how large the pectoral fins are. They are (at least proportionally) the largest of any whale species. Unlike most fish, that use pectoral fins more for steering than thrust, whales move their bodies through the water with their pectoral fins (they have no pelvic fins) and their tail flukes (horizontal rather than vertical like a fish’s caudal [tail] fin). A whale’s swimming motion is undulating (up and down) rather than side to side like a fish. This is similar to a dolphin’s style of swimming, and also incidentally an Olympic swimmer doing the breast stroke.

Ernie Marshall taught at East Carolina College for thirty-two years and had a home in Hyde County near Swan Quarter. He has done extensive volunteer work at the Mattamuskeet, Pocosin Lakes and Swan Quarter refuges and was chief script writer for wildlife documentaries by STRS Productions on the coastal U.S. National Wildlife Refuges, mostly located on the Outer Banks. Questions or comments? Contact the author at