Ruby-throated hummingbirds fly 500 miles nonstop from Mexico the eastern United States by themselves. From the time of James Herriot to modern 24/7 practice, some aspects of veterinary medicine will never change. Then as now, we do not know what will walk in the door, what surgical skills will be required of us, what complicated treatments must be instituted, or what conclusions must be determined and deftly explained. This makes for interesting work days. Alas, performing at the ragged edge of ability, efficiency, performance, and limitation as we do, it is no overstatement to say we experience hard days. When your stamina flags, one of the best ways to boost motivation is to recalibrate your perspective. Yes, our work is exhausting, but not as exhausting as the work day some of our friends in the animal kingdom experience. Pint-sized paragons Let’s talk hummingbirds. Most of them weigh three to four grams. That is less than a marshmallow, about the weight of three paper clips; we can safely say, “dinky.” Despite their diminutive size, they have monster metabolisms, eating up to three times their body weight per day in nectar and insects to replenish the calories they burn. One Cornell Lab of Ornithology researcher stated this is roughly equivalent to us eating 300 hamburgers per day to keep up with metabolic demand. I wish. Hummingbirds are the only birds capable of flying backward due to a remarkable figure-eight wing stroke that has been studied by the military for developing flight technologies. They are smart, too. Studies bear out the fact they can remember each flower they have visited. With brains that make up 4.2 percent of their body weight (compared to the measly two percent of body weight our brains make up), they have clearly got brains and brawn. Life flight Now for the really good stuff. The ruby-throated hummingbird travels from its wintering grounds in the Yucatan peninsula in Mexico to its breeding grounds in the eastern United States and back again each year. True, other birds migrate longer distances, including ruby’s cousin, the rufous hummingbird, which keeps flying all the way to Alaska. However, the wee ruby-throated champion makes its flight straight across the Gulf of Mexico, 500 miles—nonstop. Through storm and wind, blazing day, and dark of night, this hummingbird does not travel as part of a flock. This is a solo journey, 20 hours straight of do-or-die flight across an ocean, alone in the world. This is what I mean by recalibrating your perspective. Imagine yourself prepping for the trip. First off, you must lap up enough nectar and energy to double your fat stores but still be able to fly. This is a close thing, considering you will be so stuffed you will often leak globules of fat through your skin. Then off you go, flapping your two-inch wings endlessly, transitioning from glucose to fat metabolism at the flip of a switch, making the trek on the caloric content of just one and a half gram of fat. Did you catch that? The amount of energy needed to propel a human 50 feet up a ladder pumps those bird wings through 500 miles of flight. Sometimes birds are so exhausted they simply fall out of the sky. If you make it far enough to guzzle some recovery drink, Florida-nectar-style, you will be a mere shadow of your former self, having lost half your body weight in a single day. If we humans were to endure such weight swings twice a year, we would be metabolic messes. Additionally, a hummingbird’s post-prandial serum glucose peaks at a whopping 740 mg/dl; their fasting serum glucose only goes as low as 300 mg/dl. This is some high-octane blood. It stands to reason these guys would spill barrels of glucose into their urine and develop raging diabetes from day one, even without the stress of migration turning their metabolisms inside out. Yet, hummingbirds do not get diabetes, and no one knows why. Instead, these tiny birds fly across an ocean in a day because this is what they must do to breed. They get it done. Simple as that. Pulling Gs Enough about endurance. Let’s talk performance. The courtship display of Anna’s hummingbird males is worth a play-by-play description. These little guys zip 130 feet into the air, then accelerate into a dive. By accelerate, I mean sprint, wings flapping at 200 beats per second, heart rates reaching 1,260 beats per minute until they hit 60 miles per hour, then they tuck their wings and plummet, torpedo-like, into a near-vertical dive toward the ground. When the male comes within 10 feet of the female, he opens his wings and tail feathers wide, straining with all his might to pull up. The speed of the wind through his tail feathers makes a characteristic chirp sound. The ladies like the chirp. The faster the dive, the louder the chirp. He launches himself back to his 130-ft altitude and repeats the 60-mph dive, over and over, until the missus leads him to her nest for a little lesson on the birds and the bees. Here is the remarkable thing: during the tail chirp maneuver, these hummingbirds pull a gravitational force equivalent (Gs, or G-force) of nine. Quick reminder: this means a 200-lb human would feel like he weighed 1,800 lbs. That’s the maximum a fully trained pilot in a pressurized G-suit, with special breathing and muscle tensing techniques, can endure (and only for very short periods of time) before experiencing G-LOC (loss of consciousness). Every high-performance pilot gets Geasles (petechia from cutaneous blood vessels rupturing in the extremities), and many deal with back and neck pain from G-force stresses across their vertebrae. The air force trains its most elite pilots to endure nine Gs because this is what modern fighter jets like the F-16, F-22, and F-35 can pull during hard turns. One man, Major Laszlo Szatmari of the Hungarian Air Force, has made a name for himself as the “9 G Monster.” Most pilots obtain their nine-G qualification by the skin of their teeth. Laszlo, on the other hand, can endure nine Gs for a bone-crushing 30 seconds straight. YouTube videos (https://www.youtube.com/watch?v=-3BO2U72YZE) of him in the training centrifuge show a man at the absolute limit of function: skin sagging, jaw clenched, neck bulging as he sips air into his lungs and forces blood into his brain. It looks excruciating. Yet, the Anna’s hummingbird pulls nine Gs every spring to impress the ladies. His wings ought to rip off his pectoral muscles. He ought to lose consciousness, have blood vessels burst under his skin, and splinter every featherweight bone in his body. His courtship dance must surely hurt, but instinct directs him to reach deep and do it anyway. Perspective So, the next time you face a situation at work or in your personal life forcing you to push past your limits, remember what a “hard day” looks like for these two tiny hummingbirds. They have always been beautiful—thrumming, darting, iridescent jewels that they are. Yet, very recently, they have become outright heroes to me. I hope their iron will to overcome the challenge of a 500-mile ocean flight or a nine-G dance also inspires you. Holly Sawyer, DVM, worked 19 years in small animal private practice before joining GuardianVets to train and coach the veterinary professionals who deliver 24-hour triage support to hospitals. In her free time, she snowshoes and hikes with her two dogs and bakes chocolate chip cookies, not always in that order. Writers’ opinions do not necessarily reflect those of Veterinary Practice News.
