Can you remember your first nest?

I can remember mine. I was in the fifth grade. A hummingbird made a nest on a slender tree branch right outside my second floor bedroom window. It was so close I could have raised the window and touched it, but I didn’t dare. The cup-shaped nest was tiny, as you can imagine, about the size of the tip of my pinky finger. I’d sit at my desk and watch the hummingbirds come and go.

I’ve long had a fascination with how birds choose their nest sites and the construction materials they use. Here, in YLP, right now, this miracle of nature is playing out for us all to observe.

Nests, and nesting sites, are as varied as there are birds.

If you are a member of the ACE, the Avian Corps of Engineers, like a red-tailed hawk, you are going to construct a rugged platform in the crown of a tall tree, like one of our towering bull pines. The nest will have a view of the landscape all around. It needs to be sturdy because it will be used more than one year. A red-tail nest can be as big as 3 feet wide by 3 feet deep. A bald eagle nest, in comparison, over the course of several generations might weigh a ton or more, so it would need a more sturdy tree, like an oak.

Red-tailed hawk

Great blue herons and great egrets like the company of family. They construct spacious nests in close proximity to each other high in the tree canopy. Some rookeries may have fifty or more nests.If there are hungry chicks begging for food, the din is so loud you can’t miss hearing it if you pass anywhere nearby. Last year we had a rookery in the bull pines near Corral, but not this year.

Great blue heron

Common ravens make a secure nest site in the crook of rigid tree branches. There are several nests around Blue Heron Lake, quite visible from the trail, and another one near the sand volleyball court. No need to conceal the nest, ravens are big and aggressive, and will defend the nest against a marauders like red-tailed hawks.


Like many birds who are at the mercy of predators, the western kingbird builds a nest that is fairly well hidden. with small twigs and other pliable materials. And, just like human designers, while it is at the task of getting things just right, why not add a bit of flare, such as a flash of color to finish things off?


Many species seek protection from the elements, as well as protection from nest robbers. Our oak trees provide an unending supply of tree cavities that become nesting sites for brooding pairs of wrens, nuthatches, titmice, and woodpeckers. They can be finicky, too, about what goes and what stays in that cavity. Last year, I watched a white-breasted nuthatch pair remove someone else’s nest material and bring in their own. What makes one tree cavity better than other is a mystery to me.


Bluebirds nest in tree cavities, too, but they will be more than happy to occupy your nest box, provided the entrance hole is 1.5 inches in diameter (to keep out larger birds), not too far off the ground, and facing the right direction. Lots of soft, pliable materials are needed for their cup-shaped nest.


I was astounded last week by the extra effort one little bushtit made to gather the right material for its nest. While enjoying the sun on my patio, I watched this bird swoop down to the ground and pull on some frayed landscape material. It pulled, and tugged, and jerked with its beak, all the while using its feet for leverage and tail for balance, until some filaments came loose. It took off, then returned two or three more times. I think the determination exhibited by this individual rivaled the Little Engine That Could.


On the opposite end of the scale from the Avian Corps of Engineers, you will find the ground nesters. Wild turkeys and mallard ducks, for example, look for overhead and ground cover to hide their nest, while turkey vultures simply lay their eggs in a crevice or hollow of a log.

Canada geese are the true minimalists of ground nesters. All they need is a shallow depression in the soil near water’s edge, and lots of goose down to keep the eggs warm while the adult is off foraging. If you keep a sharp eye, you will find geese nesting along the shore of Blue Heron Lake. Please keep your distance and do not disturb the occupants. Their honking and bodily agitation will let you know when you come too close. Too much human interruption will cause them to abandon the nest, eggs and all.

Canada goose

Would you like to know the secret of finding all the nests that are around Blue Heron Trail? I’ll tell you right now: Shush. Put your ear buds and cell phone in your pocket, and stop talking while you walk; slow down, look up and all around; listen, pause, look for some unusual activity. You will see bird nests, completed and under construction all around for the next couple of months. Really.

Be it ever so humble…

Keep birding,
Robert Groos
For more from Robert Groos, visit:

Robert Groos is a published photographer and keen observer of nature who lives in Yosemite Lakes Park. He shares some of his outstanding images of our local feathered friends along with some tidbits of interesting facts about each. We hope you enjoy them as much as we do. 

Previous posts:
Wild turkeys on parade
The Pied-Billed Grebe
Hunchback of YLP: The black-crowned night heron
The bluebird
Talking turkey
The secret world of the phainopepla
Acorn woodpecker 
Oak titmouse
White-breasted nuthatch
California quail
Bald eagle
Western kingbird
The turkey vulture