They select a breeding territory based upon an evaluation of all the things they are looking for: food supply, suitable nesting and perching trees, and isolation from excessive human activity. These areas are usually near where they themselves fledged as youngsters. Wintering birds do not establish a territory, but usually do use the same area each winter. – PN

Given the option, Bald Eagles will choose a ‘super-canopy’—one rising above the rest—tree with sturdy limbs and a commanding view of the surrounding terrain, which is also always very near to water. Typical nest heights are 50-125 feet high. On the Channel Islands, where large trees are also very scarce, Bald Eagles have built their nests on cliffs.
– PN

Both are involved. Both eagles find nesting material—grasses, sticks, branches—and bring them into the nest. Both eagles move the sticks around; sometimes both have the same branch in their beaks at the same time and walk around the nest with the stick. One eagle may place a stick in one place, only to have the other eagle move it to another place—and this can happen multiple times!

Prior to the female laying eggs, the male and female will gather lots of soft nesting material—grasses, Spanish moss, whatever is available, and build a ‘bowl’ or ‘cup’ inside the larger nest. This bowl/cup will be the area into which the eggs are laid, providing them with a soft cushion. After the eaglets have hatched, the sides of the bowl/cup will help keep them in one place where the parents can shelter them more easily.

Although no one knows for sure, some ideas by scientists are:

• these may serve as an insect repellent
• may be a clear signal to other eagles that this nest is well-tended so they better keep away.
• may provide a bit of camouflage
• may help to keep the nest clean.

– PN