Steller's Jay Harvesting Acorns

As I walk into the arboretum at the White Oak Pavilion, I am greeted by the sounds of falling acorns. Acorns are a sturdy nut with some gravity as they fall. As they drop through the tree, I can hear them brushing against the oak leaves. They bounce off the ground with a hearty thud or strike the metal roof of the pavilion with a resounding pop. I have had a couple come close to thumping me on the head as I went underneath one of the oaks. Hopefully my hat will lessen the blow.

Accompanying the orchestra of falling acorns is the shook shook shook shook vocalization of the Steller’s jay. They are busily selecting acorns and caching them for the winter. They will usually make a small hole in the ground and tuck the acorn inside by pounding on it a few times. Afterwards they will cover it with debris, such as leaves or sticks. Obviously they try to be discreet when stashing their food. If they feel that they were seen while hiding their food, they will return to retrieve and relocate it. This behavior has happened with me as I have attempted to photograph them burying an acorn.

In David Sibley’s book What It’s Like To Be A Bird he has this fascinating detail about acorns and nutrition: “One significant challenge of eating acorns is that they have high levels of tannins, which bind with proteins and makes them unavailable. Acorns are high in fat and carbohydrates, but, eating acorns alone, jays lose weight rapidly because tannins lock up more protein than the birds get from the acorns. If a bird has access to other sources of protein—enough to make up for what the tannins remove—then acorns in moderation can be a valuable part of the diet.”

Nature is an inexhaustible source of wonder. Hope to see you out there.

Sibley, David Allen. What It’s Like To Be A Bird. New York, Knopf, 2020.

Downy Woodpecker & Mullein

Downy woodpeckers can often be seen on the flower stalks of mullein this time of year. The yellow flowers steadily open throughout the season starting at the bottom and moving upward as the stalk grows. So you can see flowers blooming on top of the stalk, fuzzy green seed pods along the middle and older pods turning brown at the bottom. The woodpeckers are opening the pods and extracting small larvae inside that appear to be eating the seeds.

As I investigated a couple mullein stalks, I found they were attracting a surprising number of insects and spiders. I encountered a goldenrod crab spider, a daddy-long-legs, grasshoppers, aphids, weevils, caterpillars, honey bees, native bees and wasps all on a couple plants. My guess is that the woodpecker is taking the opportunity to sample a few of them along the way.

Red-breasted Nuthatch Collecting Seeds

Sitting in the shade of a ponderosa pine listening to the river flow, I heard the faint murmurings of the red-breasted nuthatch. The pine cones are beginning to open in the warm, late-summer sun and the nuthatch is on the scene to start collecting seeds for the winter. After retrieving a seed, it flew over and stashed it in the furrowed, mossy bark of a bigleaf maple. It merrily went about filling its larder for most of the morning.

Occasionally, it would take a break and forage for food - pine seeds, insects, spiders and other arthropods. All About Birds by Cornell Lab summed up their foraging behavior nicely: “Red-breasted Nuthatches move quickly over trunks and branches probing for food in crevices and under flakes of bark. They creep up, down, and sideways without regard for which way is up, and they don’t lean against their tail the way woodpeckers do. Flight is short and bouncy.” I will add that you will often see them facing downward, pausing to tilt their head upward to survey their surroundings.

Listen for the sound like a small tin horn as the red-breasted nuthatch toots and squeaks on its joyfully spirited way through the landscape.

Nature is an inexhaustible source of wonder. Hope to see you out there.

Resources:
https://www.allaboutbirds.org/guide/Red-breasted_Nuthatch/lifehistory

Wood-Pewee Fledged

I saw two of the three wood-pewee fledglings nearby along the river in a willow shrub. The parents were dashing by and feeding them in what seemed like a fraction of a second. This fledgling sat quietly on this small branch and patiently waited. I watched it for about a half an hour, and I never heard one peep out of it. Usually fledglings will vocalize with a begging call to be fed, but it can also get the attention of predators. Perhaps this little fledgling has already had a close call and has decided to sit and wait silently.

Last Nest of the Summer?

The Western Wood-Pewee has been, in my experience, the last bird nesting of the season out at the arboretum. That said, there was a robin’s nest nearby where the fledglings just left the nest within the last week. The baby pewees look as if they are going leave the nest any day now. They are fluttering their wings, preening their feathers regularly and perching on the side of the nest. There are three in the nest which seems crowded and hard to believe when you look at the size of the nest.

The parents stay close by to the nest. They could easily be back at the nest at a moments notice if a predator, such as a Steller’s jay, gets too close. The parents perch on small, exposed tree branches as they watch for insects flying by. They will swoop out in a small loop to catch an insect, and they will often return back to the same spot as if an invisible rubber band snapped them back.

The babies have insatiable appetites, and the parents are returning every couple of minutes to stuff food in their bright yellow bills. I can hear the babies almost constantly calling out from the nest to be fed.

I am sure the parent pewees welcome the closing of the day to get some well deserved rest.

Eurasian Collared-Dove

There is often a pair of these doves around the entrance to the arboretum. They have a black crescent around the nape of their neck that is prominently visible against their light, chalky-gray bodies. When they are perched or walking around on the ground, you can see that their wing tips are slightly darker than the rest of the wing.

They mainly forage along the ground for seeds, and they will also eat berries and insects.

This bird was accidentally introduced into the Bahamas in 1974 and by the 1980’s they had made their way over to Florida. Since then they have spread across the United States, except the Northeast where only a few strays have been recorded. In reading about them, I didn’t find anything reporting negative impacts on the populations of native birds.

Cool fact from All About Birds:
”The Eurasian Collared-Dove’s species name, decaocto, comes from Greek mythology. Decaocto was a servant girl transformed into a dove by the gods to escape her unhappy treatment; the dove’s mournful cry recalls her former life.”

Green Heron

Green herons are solitary birds and quite secretive. If I sit quietly in the morning along the river out at Mt. Pisgah, I might be fortunate enough to see one. Their coloration and pattern easily conceal them as they hunt in the shallow waters along the vegetation of the river’s edge. They can be seen standing motionless or slowly walking along the bank as they look for food. When catching prey, they will quickly lunge forward darting their head into the water with their stout, pointy bill.

Their diet mostly consists of eating small fish. Also on the menu are insects, spiders, crustaceans, snails, amphibians, reptiles, and rodents.

Amazingly, green herons will sometimes drop a feather or small twig on surface of water as bait to lure fish. I would love to see them do this.

I was lucky to get a photo of this one as it investigated the shallow water of this bar of cobblestones.

Cow Parsnip Cache

Surprisingly, so far only once this year have I observed downy woodpeckers extracting the larvae of the carrot seed moth out of the hollow stems of cow parsnip. In years past, I saw the woodpeckers on the cow parsnip all the time, usually feeding juveniles.

The evidence of the presence of the moths is the seed heads have been eaten and there are small holes bored into the stems of the plant. I opened a few stems at these holes, and I found the larvae which has small black spots on it. It looks like the caterpillars are also eating the plant on the inside of the stem. I also found little, brown cocoons which I am guessing are also the same moth.

It is amazing to see the transformation of this plant. It grows so tall developing huge leaves in the spring and early summer. Its umbrellas of white flowers are so prominent on the landscape. Now the plant is brown with shriveled leaves. Many of the plants have fallen over or broken in half leaving only the stalks standing.

Hairy Woodpeckers & Oak Galls

I watched two hairy woodpeckers, a female and a juvenile male, opening oak stem galls and eating the larvae inside. While the juvenile was getting the hang of extracting the larvae, the female was periodically feeding him. It didn’t take the female long to open one and find the larvae inside. The center of the gall had a woody core that housed several larvae in different chambers. It was fun watching them open the galls with ease. Debris was noticeably accumulating on the ground as they enthusiastically unpacked the spongy insides to get at the prize.

Different Birds Feeding Fledgling

For about a week, I have been watching a spotted towhee and a black-throated gray warbler feed this fledgling. From looking at photographs online, I think this fledgling is a brown-headed cowbird.

Cowbirds don’t build nests. They lay their eggs in the nests of other birds which will feed and nurture the cowbird when it hatches. A common host of the cowbird is the spotted towhee. Cowbirds don’t have brilliant colors or patterns, but they are a fascinating bird. Below, I included a link to a small, interesting article about them.

So maybe the towhee is the foster parent of the cowbird and somehow this warbler got its wires crossed and is helping out. All About Birds had this to say about it: “…bird parents have an intense instinct to nurture young at the time their own young are dependent. Sometimes if a bird loses its own young, it ends up feeding another chick who is begging.”

So, I’ll just keep watching and see what happens. So far I have been able to find this little fledgling each day. That said, it is getting bigger and more mobile — it flew around the creek trail quite a bit today, but it is more or less staying in the same general area. If you want to go check it out, go up the creek trail where the picnic tables are. Today it was hanging out near the first bench you come to on the right that is next to the creek. Just listen for the twittering sounds of a begging bird.

Today, I saw a juvenile towhee nearby being fed, but I’m not sure if it is the same parent towhee that it is feeding this mystery fledgling. Also today, about 50 yards away I saw a female cowbird being chased away from the nest of a western wood-pewee.

Check out these small, interesting articles:

https://www.audubon.org/news/how-does-cowbird-learn-be-cowbird

https://www.allaboutbirds.org/news/i-saw-a-little-bird-feeding-a-much-larger-bird-is-it-rare-to-see-two-different-species-feeding-each-other/