Our new children’s book, When You See Flukes, is here! It’s a 32-page, full color, illustrated book for primary-grade children (but you’ll find plenty in there to interest older kids and adults as well!) To order individual copies, email us. Or if you’re interested in retailing the book, contact our distributor, Taku Graphics.
We just got the advance copies of When You See Flukes, and I was flipping through looking at the print quality on the illustrations. It’s always a little unnerving to see this stage, because you notice color variations from the originals… but pretty soon that fades and you come to terms with the results.
A couple of the illustrations caught my attention this time–the ones that show the whales’ eyes. In doing these paintings, I studied many photos of humpback whale eyes, and read quite a bit about them. But they’re still tricky and mysterious. Underwater fish-eye cameras don’t, I’m sure, do them any kind of justice. Still, I wanted the illustrations to convey the intelligence and attention of the whales, and for we visually-oriented primates, the eyes are really important.
A humpback whale’s eye is fundamentally built like ours, but there are some striking differences. Of course the whale eye is bigger (about the size of a navel orange). The sclera (outer membrane) is very thick and strong. There are muscles that control not just the turn of the eye and the motion of the lids, but also the protrusion of the entire eyeball. The cornea is not smoothly rounded, but has a flattened area. The pupil, when contracted, forms a kidney shape. The lens is spherical where ours is flattened. There is a substantial light-reflecting membrane (tapetum lucidum) on the retina, and the retina also has not one but two areas of high sensitivity (foveae).
All of these differences appear to help maximize the whale’s visual abilities in its ocean environment. The thick sclera helps hold the eye shape under hydrostatic pressure. The ability to protrude the eyes probably gives the whale a greater range of vision, and may even grant it binocular vision in the region below its throat. The irregular cornea may allow the eye to function like bifocals–helping the eye to focus both in the water and in the air. The kidney-shaped contracted pupil creates two fields of view on each eye, with light directed to the two foveae–a nifty trick that could (?) help with underwater or above-water vision. The tapetum lucidum maximizes the light that passes through the retina, assisting with vision in the depths.
Just ran across this news item about an exciting sighting–a North Pacific right whale (Eubalaena japonica) off of British Columbia. According to the story, these whales have been sighted in Canadian waters only six times in the past 100 years. According to my National Audubon Society Guide to Marine Mammals of the World, North Pacific rights are among the world’s “most critically endangered mammals”–there may be as few as 100 left (though the Huff Post story says “a few hundred;” perhaps a more recent estimate).
The whale was observed and photographed by biologists aboard a Canadian Coast guard ship. Watch the video on the link above for some great footage. You can see the big yellowish callosities on its rostrum (the yellowish color is usually due to infestations of whale lice), and the distinctive V-shaped spout. As the whale submerges, watch for the long, smooth back (no dorsal fin), and, at the very end of the clip, the big flukes.
An interesting note: the biologists observing the whale included John Ford and Graeme Ellis, both of whom have been conducting whale research for many decades. Those two have witnessed some great sea changes in our understanding of whales and in our attitudes toward them, as well as dramatic changes in some whale populations. How fitting that they were among the ones to share this rare sighting.
By now most of us are familiar with the photos of sea lions strangling in loops of plastic, tales of sea turtles ingesting plastic bags that they’ve mistaken for jellyfish, and accounts of albatross chicks with proventriculi packed with plastic shards. We’ve been alarmed at the thought of large pieces of tsunami-spawned debris bringing invasive marine species to our shores.
But it’s not just the larger pieces of marine debris we should be concerned about. The problem extends down to the tiniest plastic particles, which easily drift to places we’re accustomed to thinking of as wild and remote, and enter the food chain through the stomachs of small fish.
The National Geographic Society is at work on a project to investigate and publicize the threat posed by marine debris, and it’s a fascinating and sobering story. I wonder how much plastic ends up in the stomachs of humpbacks and orcas?
Bubble-net feeding isn’t a new behavior in the Juneau area (it was described by Dr. Charles Jurasz in the 1970s). But for decades, it still felt rare to us Juneau whale-observers. You’d hear one or two reports in a summer, and if you were lucky enough to see it yourself, it warranted breathless boasting to your naturalist friends. In the past five years, though, it feels like we’re seeing this cooperative technique more and more frequently. It’s still incredibly thrilling, but it seems like the thrills come more often.
Now this isn’t necessarily all due to an actual increase in frequency of the behavior. Part of it could be an artifact of more whale-watching boats being out on the water, providing more observations. Some of it could just be the result of our rapidly-increasing population of whales. Still–what if it really is becoming more widespread among the whales? The behavior is obviously very highly coordinated–it appears that each whale in the group has a fixed role or position, reflected in the consistent arrangement when they emerge at the surface (see the photo above). Questions arise: How and why do groups form and dissolve? How do new whales join? How do novice whales learn what’s expected of them?
I got to thinking about group bubble net feeding when I read an article about a different humpback feeding technique, in New England. The behavior, known as lob-tail feeding, involves tail slaps at the surface followed by bubble-feeding. It arose shortly after a drop in herring populations in the late 1970s.
In a recently-published paper in the journal Science, Allen, Weinrich, Hoppitt, and Rendell analyzed 27 years of observations of this “foraging innovation.” According to the study, lob-tail feeding rose in frequency and diffused through the population during subsequent years when sand lance populations were high. The analysis provides strong support for a model of cultural transmission–that is, the evidence suggests the whales are learning the technique from each other, not independently inventing it.
The study invites comparison and speculation… Are we seeing a similar increase in the Southeast Alaskan technique? And what about diffusion not just to other whales, but to other regions? As of this year, cooperative bubble net feeding is not known outside of southern Alaska. Will it eventually be transmitted to other humpback populations? It’s fun to be at the epicenter of such as mystery!
For a lot more on humpback social foraging research in Southeast Alaska, check out the Alaska Whale Foundation’s website.
We took a quick trip out to the North Douglas boat launch this morning. As we pulled down into the parking area, a humpback whale surfaced approximately 50 feet from the launch dock. While it’s not unheard-of to see whales in Fritz Cove, this one was remarkably close to shore. As we maneuvered the boat to the ramp, the whale lunged through the surface about 60 feet from the beach.
Other clues told us there was something big going on under the water. Scores of murrelets, clouds of gulls, and several eagles were making dives, probably for the same prey the whale was targeting. And of course the weekend king salmon fishers were carouseling around too. We watched one boat putt by; the driver and passenger didn’t even glance to the side as the whale surfaced nearby. One boat driver told us the whale had been making its own rounds of the area for hours.
Wish I had a photo to post, but my camera was buried deep in an inner pocket and it took so long to extract it that the whale was down and disappeared by the time I had it ready…
Flame is one of our favorite whales. In 2011 she had her first calf (that we know of). We watched her teach her calf, who we nicknamed Spark, how to lift its flukes when diving. Spark seemed very precocious. We haven’t seen Spark since that fall, but saw Flame in the summer and fall of 2012.
On New Years Day of this year, we saw five whales feeding in the Fritz Cove area, and were able to identify Flame among them. They were accompanied by a couple dozen sea lions that seemed to be following the whales to feed on the leftovers.
In March, a friend filmed a whale feeding with sea lions near Eagle Beach. He showed us the footage, and to our surprise and delight, it was Flame. The period between the two sightings was so short that we think that she may have stayed all winter, though we haven’t heard of any sightings since mid-March so it’s also possible she may have left for Hawaii very late.
In other news, we’ve sent the book off to the printer, now we wait! We should have it in hand in 6-8 weeks.