First off... Who am I to call anyone a "nerd"? And before I get started, what's so wrong with being a "nerd"? Isn't a "nerd" just someone who knows a lot about something they're passionate about? Well if so, count me a bird nerd*.
*I would like to qualify my previous statement by saying I am a PREDATORY bird nerd. So let's learn and discuss more about these incredible animals.
Now... I remember laughing at my mother about three or four years ago, when I looked at her iPad and saw a bird-identification app on it. "Aww mom, you're such a bird nerd." I said laughing at her (passion and) interest. Little did I know that very same interest in birds was lurking inside me, the way an Eastern Screech-Owl (Megascops asio) hides in a hollow spot in a tree.
I paid the app little mind and went about my business, laughing at my own "bird nerd" quip, as if I was the first person to ever make that joke.
What I failed to realize was that simple line would stoke the fire of curiosity in me and it wouldn't be long before I found my own bird-nerdiness coming into its own. But while my mom was and remains interested in birds in general, I found my interest taking me towards the predatory side of these incredible winged creatures.
Although I am 42 years old, my mom is still teaching me, or at least showing me the path to educate myself about things that interest me. So when it comes to owls, I was impressed to learn there were two types! First there are true owls or typical owls (family Strigidae), which are one of the two generally accepted families of owls. The other being the barn owls (family Tytonidae); they differ from the Strigidae in structural details relating to the sternum and feet. Even I had to look that one up, and for the Owl Prowl program we offer here at the Museum (which happen about once a month), that sort of physiological trait is beyond what I typically teach but interesting to learn nonetheless.
Okay, side note over. What is it about these and other predatory birds that makes them interesting enough for me to admit my nerdiness?
Let's start at the feet. Take a good look at the incredible talons of an Osprey! They're angry hooks of death hanging off the bird and perfectly designed. Here, Pandion haliaetus, the Osprey, like all birds of prey, is showing its talons in action. Also called "raptors", these birds have powerful legs with sharp talons designed for grabbing, holding, piercing and killing their prey. In case of the Osprey above, the preferred prey is fish. Even the curve of the talon is important to the bird they're attached to. Wriggly fish need talons that can prevent the fish from falling after being picked from the water; Osprey even have scales of sorts to increase grip! Typically three of these talons face forward and one backwards but some raptors can rotate this back toe if need be! Their leg muscles allow them to clamp their talons into and onto their prey until the bird is ready to let go. I think these toe-daggers are absolutely incredible!
Move further up and you will find a body perfectly and only designed to be carnivorous. Whether you're talking about the Osprey, Eastern Screech-Owl and their preferred prey, or the carrion-eating Turkey Vulture (Cathartes aura), these birds dine on one thing and one thing only: meat. Active hunters require the calories that only meat can provide. And yes, the first time you see a Turkey Vulture eating a dead animal by the side of the road with it's close-to six-foot wingspan, you might be scared (or grossed out) but this raptor is a vital part of the ecosystem. Eating the dead animals that would otherwise encourage disease. Because they do eat carrion, they have some of the strongest stomach acid; they can even eat meat that's tainted with anthrax, rabies or even tuberculosis without getting sick! Before we even think about what an incredible adaptation THAT is, let's move further up... to their beak.
Their beak is what distinguishes it from all other birds. This is no different when discussing other birds such as a Northern Cardinals, Ruby-Throated Hummingbirds or Flamingos. Bird beaks give you an idea of the diet of the bird to which they are attached. In the case of raptors they are made for rending, tearing chunks of meat off their prey and even cutting spinal cords of animals! Hooked at the tip with cutting edges, their beaks allow birds such as the Golden Eagle, (Aquila chrysaetos) to rip off chunks of flesh, and feed to their offspring or consume it themselves. If the bird you looking at has a beak like any of the birds pictured here, you're dealing with a raptor.
Right behind that beak are the eyes, another hallmark of raptors. All raptors have binocular vision, like you and I do. Able to see in three dimensions and with much greater acuity than you and me, the eyes allow hawks, eagles, owls, kites, harriers and other raptors to lock in on their prey from far away and keep their eyes focused during their hunt. This is in part because of the size of their eye in relation to their head, their muscles that allow for rapid focus as well as the high-resolution of their retina(s). Diurnal (daytime) hunters have full-color vision like you and I do, and concentrations of sharp vision on their retinas. Perfect for when you don't want to lose sight of a dinner item that may be running, flying or swimming away from you. They will keep this focus in flight, moving their body around their head as to keep their focus on their prey.
Their nocturnal cousins have another set of adaptations to help them. And according to the Bureau of Land Management, "Owls have a concentration of rods in their retina that are used to see in low light conditions. An owl's eyes are also located in the front of their heads, much like humans, giving them a larger area of binocular vision." Interestingly enough, owls cannot move their eyes and their eyes are not spherical like ours, rather they're tubular and they must move their head to look at something. This is why they have so many extra vertebrae in their neck and why they can to turn their heads almost 360°, like this Barred Owl is demonstrating below.
I've sat here on the property of the museum during the day, and heard the local Osprey making all sorts of noises as they hunt, fly and raise their chicks. I've walked through and sat in the woods at night, calling to and hearing from Eastern Screech-Owls, even seen them in the trees! I watched as a Red-Tailed Hawk intimidated me into moving away from the rabbit it had just killed and was protecting. I've left at dusk and heard Great Horned Owls hooting in their haunting duets but I must admit, I cannot get enough of these incredible animals!
Predatory birds are my jam! I am not afraid to admit it anymore. To think that dinosaurs, non-terrestrial dinosaurs, SURVIVED the impact 66 million years ago is mind boggling!! And yes, It’s official: birds are literally dinosaurs; that's an article from Bird Life International. Paleontologists once thought that the earliest bird, 150-million-year-old Archaeopteryx, represented a great evolutionary leap from dinosaurs. Now we know the "great leap" was simply the next step in bird/dinosaur evolution. And if you're really feeling like you need more, check out this article from Scientific American in 2015.
Let me end by saying, I am sorry mom.
I am sorry I laughed at your bird app- it's called Merlin, if any of you out there are interested- I am sorry I doubted how cool birds could be and I thank you. Thanks for continuing to foster my curiosity and reminding me that knowing a lot of about a subject you like is the height of coolness. My name is Frank and I am a predatory bird nerd.
Bird nerds unite!