Views and News from the Natural World

This Oregon junco, one of the most common birds in the Pacific Northwest, evolved at a very rapid rate as glaciers retreated 10,000 years ago. DNA studies tell us that the ancestor of this and all of North America’s millions of juncos spread from coast to coast, from Mexico to the arctic, was the Central American yellow eyed junco. All North American juncos are dark eyed. This rapid evolution provides only one of many reasons that ornithologists and others find juncos to be libraries of important information.

Scientists have found that a junco that would die at 4 degrees centigrade in summer can survive -9 degrees in winter since its metabolism changes to suit the seasons. It spends almost 30% of its time on the ground foraging for seeds and small insects and other invertebrates. Here on the Oregon coast seeds from fir cones become a large part of its diet. The junco often feeds with other ground feeders but among other juncos a strict pecking order is enforced.

In some areas the males have black heads, while in other areas the heads are dark gray or blue-gray. The colors of the back and sides vary from dark brown to bright cinnamon to pale pinkish brown. This member of the sparrow family is one of the most diversified species on this continent. DNA now suggests that the 5 or 6 varieties of juncos in North America are subspecies of the general category dark eyed junco. In a colony isolated in San Diego they seem to be rapidly developing into a new species of junco.

Oregon juncos have the same white tail feathers that show in flight as other subspecies, but the feathers of the back tend to be a richer brown. Eastern juncos are generally slate gray on the back.

Maybe one reason most people give juncos only a glance is because the birds move too fast for the human eye to appreciate their agility and maneuvers.

Scientists at Indiana University Bloomington have been studying juncos for over 100 years to learn about everything from sex to songs to aggression. Their “Ordinary Extraodinary Junco” videos and studies can be found at: https://juncoproject.org/view-download/chapter1/index.html

The Band Tailed Pigeon of the West Coast

An early European traveler to Oregon wrote, “This species is most numerous near the mouth of the Columbia River, where immense flocks were seen from May to October 1865, which fairly rivaled those of the passenger pigeon.” Genetically this pigeon is the closest relative of the extinct passenger pigeon. When the bird takes flight its vigorous wings often meet overhead and make a loud slapping noise.

These pigeons almost went the way of the passenger pigeon. Being native to the West Coast (and another clade in the high elevations of the Southwest), they did not create as strong a conflict with fruit and grain growers. However, they delighted San Francisco palettes. In 1911 hundreds of hunters came to coastal Oregon. One hunter alone sent 2,000 birds to city hotels.

The pigeons’ drive to dominate a food source leads it to treat members of its own band roughly. Its main weapons in close up combat are its beak and a wing–usually using one wing for blow.

The band tailed pigeon is among those few birds that feed their young from a manufactured nutrient–pigeon milk. The pigeon produces this thick creamy food from special cells in its craw. The high protein and fat content gives the one or two chicks hatched a strong start.

Animals are often like a Rorschach Inkblot test for humans: we see in them what satisfies our needs. I try to avoid imposing my needs on their world by making science my window.

No company has brought more attention to wild animals and more misinformation and warped perception than Walt Disney. Making any wild animal “cute” distracts from the necessary and interesting lessons we can learn from its life and a real appreciation for its own experience of life. Disney started with the blockbuster movie of Bambi and for chipmunks Disney created Chip and Dale. Disney animals are humans frolicking in drag.

The once best selling novelist Adam Saroyan (My Name Is Aram) had a cousin,  Ross Bagdasarian, who built a fortune on Chipmunk Records with chipmunks Alvin, Simon, Theodore, three chipmunk brothers singing a Christmas song in falsetto voices. Chipmunks do communicate in very high pitch, but they care more about owls and bobcats and foxes than about Christmas. When a pygmy owl, a day hunter perches near the feeder or a hawk flies low overhead, the danger signals are low pitched “chucks”. Warnings for dogs, cats, and other ground hunters are so high pitched they are almost above my threshold.

The stripes on the chipmunk help make it less visible to daytime hunters like hawks. Evolution created a gene that suppresses pigment in the striped areas.

An adult chipmunk can stuff 50 to 60 sunflower seeds into each cheek. Relative to the body weight of a 5 ounce (140 grams) chipmunk, that’s roughly equivalent to carrying two big shopping bags of vegetables out of a supermarket.

The chipmunks burrow and breed in solitary pairs but they congregate around any food source offering more than one chipmunk can stuff into its cheek pouches. Competition is fast and aggressive but usually without much contact. Occasionally a chipmunk appears missing the end of its tail or all the fur in the middle.

Steller’s Jay

The Steller’s (Cyanocitta stelleri Gmelin) is named for Georg Wilhelm Steller. Steller, a young German, served Vitus Bering as scientist and physician when Bering, a Dane, in 1741 sailed for the second time to determine if North America and Russia were joined. In 1728 at the behest of Peter the Great he had made his first attempt, passing through the Bering Strait but unable to see Alaska through the fog. To be sure the continents were not joined north of the strait in the “Icy Sea” he sailed a second time. He missed the strait but found southern Alaska at Kayak Island where Steller began cataloguing North American species.

Birds present colors in two ways–pigments in the feathers or structural color caused by the way light reflects off microscopic structures in the feathers. (Think of a clear glass prism that turns white light into rainbow colors. Some structures will reflect a much more limited spectrum.) But why did this jay become blue and others gray?

The Steller’s and grays both like bread and peanuts, but the Steller’s do not usually eat the cat food that the grays eat. And the grays do not eat the unshelled sunflower seeds. For more competition see the pictures below.