A tale of two tough birds

Charlotte County Animal Control strikes again.  I do not know how they do the amazing job they do, but I am glad to have them working with us at Peace River Wildlife Center.  Thanks to CCAC Officer Nord and a bevy of helpful citizens, an injured bald eagle is resting comfortably and recuperating at PRWC.

The eagle had been seen running around on the ground, but was nowhere to be found by the time rescuers got to the area.  The next day she was reported to be flying into windows at a nearby business and again taking off on foot.  Officer Nord was finally able to locate the confused bird, track her down and take her into custody.

With no obvious injuries, the adult eagle is assumed to have been suffering mild head trauma.  She weighs in at more than 3kg (7lb), so we are pretty confident she is a female.  As with all raptors, the females are larger and heavier than the males.  She is in good flesh, not dehydrated, has good muscle tone and a pretty feisty attitude.  How on earth Officer Nord was able to catch this bird is beyond our ken.

The eagle spent one night in the surgical/isolation ward.  She was perching and well aware of her surroundings.  She was transferred to an outdoor habitat in the morning, where she continues to eat and get even stronger daily.

Since late September is the start of mating season for Florida’s eagle population, she may have been injured trying to locate a nest sight and mate.  She was seen striking a window with her feet, so she may have been defending her territory from another invading female (her own reflection.)  Birds often fly into windows accidentally or intentionally as they see foliage or themselves reflected in the glass.  If this is a recurring problem at your home or place of business, stickers can be placed on the glass to help decrease injuries to the birds.

While most bald eagles return to the same nest site and mate each year, if either is no longer available, the survivor will find a new mate and build a new nest or steal one from another large bird (like a great horned owl.)  With Florida’s temperate climate, the eagle’s breeding season can range from October to April, but most clutches are laid during December and January.

A bald eagle nest can be quite massive.  Returning to the same nest each year, the birds may add to it annually until the weight of the nest is more than the tree can support and either the nest or the entire tree falls.  Constructed near, but not at, the top of the tallest tree in the vicinity, the nest affords the birds shade from the sun and a good vantage point to monitor activity in the area.  The eagles often have an alternative nest sight within their territory of approximately one square mile.  They may switch sites if they have an unsuccessful season due to too much noise and commotion or too many predators.

The average clutch size is two eggs and incubation generally takes about 35 days.  Incubation begins as soon as the first egg is laid, so the eggs may hatch one or two days apart.  This is in contrast to some bird species that lay an egg a day over a period of time and do not begin incubation until the last one is laid, ensuring that most of the offspring hatch at approximately the same time.  Due to the rapid growth of the eaglets, the difference in size during the first few weeks can be a determining factor in the welfare of the chicks.

The parents will usually feed the oldest chick at every feeding.  If there is enough food after that baby is full, then they will feed the second.  So not only has the first-born started out larger, but has the advantage of better nutrition.  In this manner, the birds help to ensure their survival even in times when food is scarce.

As the hatchings grow, the competition for food and attention from the parents can get brutal.  The smaller sibling can be bumped from the nest by a larger more aggressive nestling.  While many people may find this practice unfortunate, it is vital for the natural selection process to ensure the survival of the species.  The strong survive.

If this is true for people as well, I have a healthy respect for CCAC Officer Nord.  Her ability to hunt down and capture an adult bad eagle that can run and sort of fly is admirable.  I do not, however, ever want to find myself at the top of a tree with her.  I may be just a tad older than she is, but I have a feeling she would win a shoving contest.

by- Robin Jenkins, DVM

An adult bald eagle recuperates in a cage at PRWC.
An adult bald eagle recuperates in a cage at PRWC.