The bald eagle has been the national symbol of the United States since 1782. It is North America’s second largest bird of prey—only the California condor is larger. With bald eagle breeding season well under way here in Southwest Florida, let’s take a closer look at these regal birds.
Mated pairs may begin selecting sites and nest building or reconstruction as early as late September. A bald eagle nest can be quite massive. Often 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 the nest—or sometimes the entire tree—falls. Typical nests average 5 feet in diameter and 3 feet tall. The largest nest on record, in St. Petersburg, Florida was 9.5 feet in diameter and over 20 feet tall.
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. Nest shape depends on the tree in which it is located and can be flat, conical, or cylindrical. 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.
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, if necessary, build a new nest or steal one from another large bird (typically, a great horned owl.) In Florida’s subtropical climate, the eagle’s breeding season can range from October to April, but most clutches are laid during December and January.
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 other 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 they can successfully raise at least one chick even in times when food is scarce.
During the first two weeks, the male provides most of the food, while the female tends to the young. At three to four weeks, the female brings as much food as the male, with the young pecking at the food, but relying on parents to tear the meat into edible portions. By six weeks, the eaglets are able to self-feed when supplied fish and rodents by the parents.
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 unpleasant, it is vital for the natural selection process to ensure the long-term health of the species. The strong survive.
Next week: Bald eagles, part deux.
by- Robin Jenkins, DVM
Bald eagle nest, photo courtesy of USFWS
A long time ago in a land far away, I was cursed by an evil witch. My best friend, Karen, used to babysit the child of a family friend and offered me the job one night when she had a date. It was the first time I had ever met the lady, and I’m pretty sure she knew nothing about me.
A few weeks after watching her child (during which nothing memorable happened), I heard that she had told someone I would never stick with anything. That I would flit about from job to job and never amount to a hill of beans. At the time I thought nothing of it because we were practically strangers to each other. I had no idea on what she based this prognostication and I was determined not to lose any sleep over her low opinion of me.
Through the years, as I flitted from job to job, I began to fear her words were more of a curse than a prediction. I began working at the tender age of five in a relative’s restaurant, washing dishes and peeling potatoes while I stood on a chair to reach the sink. Since then I have been a night auditor, a cashier, a bartender and a phlebotomist. I have cleaned bed pans in a nursing home, detailed automobiles for auction, sliced lunch meat in a deli, and waited tables (for which I proudly hold the title of World’s Worst Waitress!)
Labouring at each of these jobs, sometimes two or three at a time, often while putting myself through school and supporting my elderly mother, I worried that Brenda was right. It wasn’t that I was never happy with where I was, but that each position was a step toward a loftier goal.
Having volunteered at Peace River Wildlife Center for 9 years (and been on the payroll for more than four now), it seems my meandering path through life has stalled a bit. But I still can’t seem to stick to doing just one job.
At PRWC, the only thing more varied than the number of different species we see every day is the reason they are here. A mourning dove with a broken wing from a cat attack. An osprey that has been shot because it was perching atop a sailboat. Raccoons suffering from distemper and gopher tortoises with shells crushed by cars. For some of our patients, the only thing we can do is ease their suffering. Many others we are able to provide medication, support, and nutrition as we wait to see if their damaged bodies will heal.
Among this week’s admissions were two hawks that had wing fractures. X-rays showed that both had been shot. A red-shouldered hawk had a pellet lodged at the fracture site of her left humerus. With no other injuries, she appears to have been shot while on the ground. Her injuries were so old and debilitating that we had no choice but to humanely euthanize her to end her suffering.
The other bird, a red-tailed hawk had a scattering of bird shot in his right side. He was probably shot out of the air and fell on his left wing, fracturing the ulna in two places when he crash-landed. This injury was also fairly old, as evidenced by the healing of the bone already taking place on the x-ray. This bird was in much better shape than the poor red-shouldered, but it is unknown if he will ever be able to fly again.
According to the Migratory Bird Treaty Act of 1918, it is a federal offense to “pursue, hunt, take, capture, kill, or possess…any migratory bird…or any part, nest, or egg of any such bird.” This is not exactly a new rule. 1918, folks. That was one year after my mother was born, and I’m pretty sure she rode a dinosaur to work like Fred Flintstone. While I’m no lawyer, and sometimes have trouble discerning what all the gobbledygook means in those “lawyer-speak” rules and regulations, I’m pretty sure shooting a hawk is frowned upon. Is there anyone who doesn’t get that? Obviously there are at least two people.
I realize now that all of those seemingly unrelated jobs I have had in my lifetime so far were adding skills that make my current position as director of veterinary services at PRWC so rewarding. On any given day, I go from folding laundry to triaging incoming patients, from public relations appearances to performing surgery. I now merrily flit from one job to the next, and often don’t have to leave the room to do it.
So perhaps Brenda’s warning was more of a blessing than a curse. I suppose it all depends on making the best hand with the cards you are dealt. What may be a detriment in one field can be an asset in another. You just have to find the right place to be, and I think I have.
by- Robin Jenkins, DVM
Red-shouldered hawk x-ray
Juvenile red-tailed hawk with a wing fracture.
Red-tailed hawk x-ray
This week at Peace River Wildlife Center has been a busy one. The snowbirds are returning (yay!), and the snow birds are also back (yay and boo.) While we love to have our seasonal volunteers return to help around PRWC, we are sad to see so many migrating birds admitted as patients.
The number one casualty this week has been grey catbirds crashing into windows. I’m not sure why they are so over-represented for this particular calamity. Are they some of the first to migrate? Do they have poor vision? Are they just clumsy? We have admitted 10 grey catbirds that have suffered injuries after flying into windows this week. Some of them just need a little time to recover from minor head trauma. Sadly, others do not survive the brain, spinal, and skeletal injuries sustained.
It is estimated more than a billion birds die from collision with glass annually in the US alone. They may think they can fly through the clear glass or see trees and clouds reflected and not understand the glass is there. Placing a grid on the outside of your windows with tempera paint or soap is the easiest, most inexpensive way to deter bird strikes.
There are some wonderful resources to explain why and how birds get injured by flying into windows and glass doors and how we can help. Check out the website https://www.allaboutbirds.org/why-birds-hit-windows-and-how-you-can-help-prevent-it/ for more details.
We have also seen other unusual and migratory species this week at PRWC. Some of them have also hit windows, while others were hit by cars or attacked by cats. We have had an American redstart, a red-eyed vireo, an indigo bunting, a sedge wren, a belted kingfisher and a hermit thrush. One of our daily challenges is properly identifying each patient that comes in to us.
Sometimes it is easy to ID our patient’s species. We see a lot of repeat customers—as a species, not necessarily individuals. Although we have seen the same tortoise brought back in a few times because he has an old healed injury that looks so bad it is hard to believe he is living with it, when in fact he is thriving in his home territory despite a large divot in his shell that has granulated over.
Other recidivists commonly include black vultures. Quite often vultures can live long, productive lives with a healed broken wing. We get calls periodically about grounded vultures that don’t have fresh injuries and our advice is to leave them where they are if they do not seem to be suffering or weak.
While we would never release a bird that can’t fly, if the vulture’s broken wing heals on its own (which is often the case) the bird can live with the deformity. They are still quite adept at getting up into a tree at night to roost to avoid the few predators they have. And since they eat carrion, they usually don’t have trouble feeding themselves despite the fact that they are unable to fly.
We routinely see a lot of doves, red-shouldered hawks, mockingbirds, and other native species that live here year-round. When the migratory birds are flying through the area, we are sometimes temporarily stumped as to the species. But why does it matter? There is a huge difference in how we treat and feed different types of birds. This is why it is especially important that rescuers not feed an injured bird or mammal anything. It is more damaging to feed the wrong thing than nothing at all. Even water can be dangerous if it is aspirated by a weak or injured animal.
One of the first indicators for bird identification is the beak. The size and shape can tell us a lot about what the bird eats—seeds, insects, etc. The feet can give us a clue as to where they live—fields, marshes, etc. To properly treat avian patients, we need to positively identify them. To this end, we have a library of reference materials and have just started playing with a smart phone app—The Cornell Lab Merlin Bird ID. Simply take a photo of the bird and the app helps identify the species. We have had pretty good luck with it and a lot of fun confusing it with pictures of Luna, our leucistic eastern screech owl.
I know all our birding friends are thrilled to see so many different species migrating to and through SW Florida. Areas like Ollie’s Pond, Celery Fields, and even your own back yard are wonderful places to see birds of all different types. Let’s do everything we can to help these travelers complete their journeys safely.
by- Robin Jenkins, DVM
Necessity is the mother of invention, but I have a feeling the Internet is the granddaddy of the unintended consequences. It makes me nervous to think that if I were to die under dubious circumstances that triggered a forensic investigation, I would not come out looking good, especially when they started looking at my electronic footprint.
I admit that when I first heard about bump stocks, I didn’t know what they were, so I Googled it. But that is far from what I mean. I have never searched for ways to construct bombs from fertilizer or place a devise in my shoe to take a plane out of the sky. Who does something like that?! I am referring to surfing the web for questionable content of a sexual nature. But probably not in the way that “normal” people do.
At Peace River Wildlife Center, we don’t see armadillos frequently, so when we admitted one recently I was curious as to whether it was a male or female. Some young mammals have obvious differences between the two genders (like dogs and squirrels) while some are difficult to distinguish (like cats and rabbits.) Since Google is such a font of knowledge (you can even use it to determine if the correct idiom is “font” or “fount” of knowledge, and argue with yourself over the results), I decided to look it up. Instead of typing it out into the search bar “How to determine the sex of an armadillo,” I used veterinary shorthand “sexing armadillos.” I do not recommend you try this at home.
Equally embarrassing would be a search of my phone and recent texts. One of PRWC’s rehabbers had a male squirrel in home care with a urogenital issue. Many texts back and forth between the two of us included details of his symptoms, differential diagnoses, and treatment options. And, of course, pictures of the offending (offended?) member. Quite literally.
I also get into trouble when I can’t remember a specific word I am searching for in the vast emptiness that used to be my mind. I was trying to order hanging fabric pouches for our baby mammals on Amazon Smile the other day and could not come up with the appropriate words to type into the search bar to get what I wanted. We have one that is a favourite of all the baby squirrels and opossums that is shaped like a banana.
So, I typed in “banana hammock.” Again, please don’t try this at home. Or in the office, for that matter. especially not in the office. The results are not pretty. I did finally get some satisfactory results by adding the word “ferret,” but by then, the damage was done.
The armadillo was a female (we think), the squirrel is recovering from his malady, and I somehow managed to order a “double fleece hang-n-tent sleeper for small animals.” So, the ends justified the means, but I’m not sure if the forensic investigators will be able to follow it through to what is, to me, the obvious conclusion.
I’m afraid they would stop at the first squirrel penis photo and assume I deserved whatever horrible fate I had encountered. That I had somehow instigated being buried alive under an avalanche of Cheerio boxes. Or that I committed suicide by repeatedly slashing my wrists with tiny raccoon claws. Or maybe that the pressure had finally gotten to me and I was trying to build a bomb instead of what I was actually doing—trying to invent a bottle-holder for baby raccoons to give my tattered wrists a break. Please stick up for me if they call you in as a character witness.
by- Robin Jenkins, DVM
Juvenile raccoon takes a bottle
Raccoon feeding station
No, this isn’t yet another column about my travel exploits. This week Peace River Wildlife Center admitted a raccoon in a pretty precarious position.
While emptying recycle bins in the Punta Gorda Isles neighborhood, the sanitation engineers made a startling discovery. They found a young adult raccoon at the bottom of a recycle bin with a tin can firmly stuck on her head.
Luckily for the raccoon and PRWC, they knew just what to do. They brought the entire construct to us—can, ‘coon, and all. Unable to simply pull the can off her head, we drilled a hole in the can through which the anesthetic gas was administered. Once the raccoon was asleep, we enlarged the opening at the top of the can, using a tin snip, until we could wrest the can off.
The raccoon was in pretty good shape, all things considered. She obviously had not been stuck in this predicament for long. She had no injuries except some minor abrasions, nor was she dehydrated or emaciated, as she would have been in short order if the can had not been removed quickly. She was treated and released to get back to the mischief of being a raccoon.
Whether we think of them as rascally scamps or the scourge of the earth, raccoons and many other wild animals are out there, in our neighborhoods, gardens, lawns—even in our attics. How can we diminish the potential damage to our property and help keep these innocent invaders safe?
The most important and easiest thing to do is limit food supplies. Keep trash and recyclables in secure containers. Rinse and crush containers before placing them outside. Do not feed animals outside—cat food, bird food, etc. If you must have food outside for pets, do not leave it out at night.
If you have fruit trees in your yard, remove ripe fruit from the tree and pick up fallen fruit daily.
Fish in ponds should be given a rock shelf to hide under so they do not become food for herons or raccoons.
Tree branches should be cut three feet from the house. Do not allow shrubs to get too thick and overgrown or touch the house.
Enclose the base of any decks or porches, extending the hardware cloth partially into the ground.
Place wire mesh over chimney caps, vent stacks, and gable, ridge, and dryer vents.
Keep your roof in good repair, check for loose shingles or holes in soffits or eaves. If you do find or suspect that you have a raccoon in your attic, there is a 90% chance that it is a female with babies. Do not exclude the mother without getting the babies out or giving her time to move them.
Often, making the space inhospitable for her will cause her to move her babies to an alternative nest site. Play loud music or talk radio, flash lights, and place a spill proof receptacle of something with a strong odor like an ammonia soaked rag near the nest.
If you obtain the assistance of a professional trapper or nuisance wildlife removal service, just make sure they are aware that removing one adult raccoon from the attic may not be the end of the problem. And ask them what they plan to do with the animals they remove. Some disreputable companies will drop trapped animals in water and drown them, even the babies. While some frustrated homeowners may not have an issue with that practice, many people are surprised to hear that this happens.
Simply removing animals from your property may not be the answer either. Obviously, you want to get them out of your house, but not wanting them to nest in nearby trees or other wild spaces is not feasible. If you remove a raccoon or young family from your yard, others will simply take their place.
Many people are frustrated by raccoons and other wildlife on their properties and in their homes. And while these wild animals can cause damage, killing or moving them is not the answer. We have invaded their space, so we must learn to be good neighbors to these native creatures. A few fairly simple practices can not only keep wildlife safe, but make our homes more comfortable for us and less attractive to wild invaders.
by- Robin Jenkins, DVM
Anesthesia to remove can
Raccoon after can removed