Avian Architects

Part One

If you’re a birder, a naturalist, or a wildlife photographer you already know that bird nests come in almost as many forms, sizes, types and styles as there are bird species. If you’re new to our natural world or have a developing curiosity; perhaps we can inspire you to spend more time outside observing the local birds in the springtime.

In this several part series, we’re going to share with you some of what we’ve learned over the years as well as share a few images of birds and their nests. Nests are as amazing and beautiful as the birds who build them.

Learning more about the hows and whys of nest building will not only give photographers and bird watchers better ideas for finding bird nests to view or photograph but a more complete understanding of their reproductive habits, their family behavior and their stunning lives.

For preservation and the safety of any wildlife species, it’s a must to recognize your human impact on whoever it is you seek out and observe. So, what should you do if you find a bird nest? Admire it from a distance! Use a long lens on your camera, a good scope or binoculars, photo blinds are particularly helpful and less intrusive once you’ve found a nest site and then sit quietly to enjoy the action. If a bird (or any animal) changes its behavior, you are too close.

For starters, not every bird builds a nest. Just because you find an egg doesn’t mean you should move it. Many bird nests are protected by law during spring or nesting seasons because they are considered “active” and an active nest is any nest where there are birds or eggs present. Removing or tampering with an active nest is against the law. So in the event that you discover that, for whatever reason, you have to move a nest, you can apply for a permit which can be issued under very limited circumstances. Bald and Golden eagle nests are always protected even when unused. Even for educational purposes it’s very important that you get a permit to keep an unoccupied nest. Consult with your local wildlife service or rehabilitator for advice and assistance.

No matter how small the nest, please maintain a respectful distance. With declining populations of birds around the world we must help to ensure that an individual won’t abandon the nest, or worse, the incubation process or their young if they are sensitive to disturbance or feel threatened.

For the purpose of classification, bird nests here are categorized into 12 general categories.

No Nest at all
Simple Birds Nests: Opportunistic, Platform / Ledge, Cup Shaped Nest and Scrape / Minimalist
Cavity
Pendant / Hanging Bird Nests
Dome
Burrow / Holes in the ground
Mound
Floating (Aquatic) & water adjacent
Mud

While birds can be very creative architects, we’ll start with the first category in this series, the NON-NEST NESTERS or Birds Without Nests. There are a number of species in this group that do not build nests but they do make a choice of where to lay their eggs. Beyond this is a simple scrape in the ground.

Some species, such as the common murre (Uria aalge), common pauraque (Nyctidromus albicollis), emperor penguin (Aptenodytes forsteri), nightjars (Caprimulgidae), peregrine falcon (Falco peregrinus, see below) and the white tern (Gygis alba) simply lay their eggs directly on the ground or ledge, a tree limb, in the open or a relatively secluded spot without actually having a nest structure. And short-eared owls (Asio flammeus) lay their eggs on some flattened vegetation. Many waders and shorebirds, such as plovers, lay eggs in a simple scrape on bare ground, relying on the cryptic coloration of their eggs to protect them from predation. Other birds, such as the brown-headed cowbird, are brood parasites that lay their eggs in other birds’ nests, abandoning their parental duties completely.

A White Tern (Gygis alba) will often lay its egg straight onto a bare branch without a nest to support it. Obviously it is difficult for an egg to be balanced on a branch. Strong winds will often blow it off if one of the parent birds is not sitting on it. The adults have learned through experience to share incubating duties and switch places very carefully to avoid knocking the egg off. Once it hatches, a tern chick tightly grips the branch with its strong feet and claws enabling it to balance on the branch better than an egg can, though a strong wind can still be a problem.

Some of the more unusual examples of non-nest nesting include the Potoos (Nyctibius spp.) which lay their single egg on a shallow knothole or depression on the elbow of an upward-angled tree limb or stub or on top of a broken-off tree trunk. The bird then sits on top of its chosen site, with its head pointing to the sky. In this position, it looks like an extension of the dead timber. It generally chooses stumps of similar diameter to itself.

The master of no nest nesting, however, has to be the Emperor Penguin (Aptenodytes forsteri). These birds nest in the Antarctic, where in the winter months the temperature can fall to less than -40 degrees C / F. They nest far inland and when the female has laid a single egg, she leaves for the coast to feed. Meanwhile, the male immediately takes over the care of the egg by moving it onto the top of his feet. He has special folds of skin on his belly which envelope the egg, keeping it warm and safe against all the extreme elements.

It is here that the male remains with an egg on his feet, for the next 60 days, without a meal or much movement at all until his mate returns and the egg hatches. During this time he has maintained the internal temperature of the egg at 40 degrees C / 104 degrees F. Now that’s efficient insulation!