The good news is that Bird Watchers Digest, the largest circulation magazine for average birders, has agree to print one of articles on birds – “Eat Like a Bird”
The bad news is that they already have so many stories waiting to be published, they may not get to mine until 2016. But, fear not. So you won’t have to wait so long I have posted that story below. How you enjoy it.
Eat Like a Bird
“Your Aunt Helen eats like a bird,” my mother would say. “She just pecks at her food and barely eats anything. If you don’t eat all the food on your plate you’ll grow up looking like a real string bean. So eat.”
Actually, my mother was wrong, as many people are, when describing a bird’s eating habits. Maybe she once saw a chickadee at our feeder grab a single sunflower seed and fly away or watched a robin struggle with a skinny worm. The truth is birds are not the dainty eaters most people imagine. Compared to supermodels desperately trying to maintain their trim figures, birds are pigs.
A small backyard bird commonly consumes 25-35% of its own weight every day. A larger bird such as a blue jay may eat 10% of its weight. Hyperactive hummingbirds consume their own weight in a single day. A typical adult man eats maybe 3% of his weight in a day. If he actually ate like a chickadee, he would be eating about 50 pounds of food per day. That is the equivalent of 200 quarter-pounders, hardly a starvation diet. A bird eats an enormous amount of food considering its diminutive size. A bird is an eating machine.
Birds need to eat a lot and often because flying requires energy. Yet despite their large food intake, they don’t pile on extra pounds. You never see a fat bird. It can’t afford any extra weight. Weight would slow it down, make it less maneuverable, and increase the risks from predators. Fortunately, birds have a high metabolism rate which compensates for their high food intake.
In fact, except for shrews, hummingbirds have the highest metabolism rate of any vertebrate creature on earth. As a result, hummingbirds need to eat almost continuously throughout a day, 3 to 4 times per hour. Studies show that a single hummingbird might visit up to 1,000 flowers per day and drink its own weight in nectar, while burning 12,000 calories per day.
When it comes to dining behavior, hummingbirds and small songbirds might be considered “grazers” – birds that don’t eat a single large meal but have many smaller meals throughout the day. One study showed that an individual chickadee may eat more than one hundred sunflower seeds during a day. Not all at once. Maybe a couple of seeds early in the morning after waking, then a few more several hours later, a couple in mid-afternoon, and again late in the day just before retiring.
Hawks, owls and other raptors have the exact opposite eating style. They might be considered “gorgers” – they don’t eat as often as hummingbirds. But when they do eat, they want a big feast – a large mouse or rabbit. One hearty meal can satisfy a raptor so it may not eat again all day.
Gaining Weight
At some times, some birds do deliberately overeat, usually just prior to a major expenditure of energy. For example, tiny Blackpoll warblers, weighing less than one-half ounce, make a long fall migration flight of more than 1800 miles non-stop across the Atlantic Ocean from northeastern United States to South. America. They can’t stop to eat along the way. So in preparation for this long, perilous flight they deliberately bulk up, nearly doubling their normal weight. The added weight is primarily fat, which provides energy to burn during their long journey. This binge eating is similar in concept to an airplane loading up with extra jet fuel before an extended flight. It takes more energy to become airborne but the extra reserve fuel adds many hours of potential flying time, which can be critical if they encounter strong headwinds or adverse weather. It extends their flying time and range. Since there is no place for a Blackpoll to land during its migration flight, the added range is a prudent safety measure.
Don’t Gulp
Another one of my mother’s common admonitions was “Stop gulping your food. Always chew it carefully before swallowing. It will taste better.” Birds gulp their food, swallowing an entire seed without chewing it. They can’t chew. They don’t have any teeth. It is believed birds lost their teeth as part of the evolutionary process to reduce their weight for improved flying. So they gulp their food whole.
How do birds taste their food without chewing? Humans have about 10,000 taste buds, mostly located on the rear of the tongue. The human tongue is soft and amazingly flexible. A bird’s tongue is hard and stiff with less than 50 taste buds, so they don’t expereince the same taste sensation we do. Yet, countless studies have demonstrated that birds do have taste preferences. One bird will prefer Seed “A” over Seed “B” but won’t touch Seed “C” at all. Finches, for example, love nyjer/thistle seed but other species won’t eat it.
Scientists have experimented by adding various flavoring to water. Birds could tell the difference. When hummingbirds are offered the choice of water with different concentrations of sugar, they always choose a particular concentration, not too sweet, not unsweetened, just right. Waxwings test the sugar content of berries to determine if they are sweet and ripe enough to eat.
A British ornithologist tested his backyard birds. Taking a large bag of identical seeds, he dyed some of them yellow, some red, and some blue. His birds showed a definite preference. They ate the yellow seeds first. When the yellow ones were gone, they ate the red ones. And, finally, when there was nothing else, they ate the blue seeds. Why? He speculated that yellow was the color nearest to natural wheat or grain seed, while few edible things in nature are blue.
If you watch a bird’s feeding patterns at your bird feeder, you may notice a chickadee pick up one sunflower seed and drop it. Then it picks up a second or third seed before finally selecting one to eat. Why do they prefer one seed over another? It takes the same amount of effort to break open any seed. So the bird chooses the heaviest seed, which yields the most food for their effort, the biggest bang for the buck.
Good Nutritional Guideline
Nutritionists have many reasons to frown at a bird’s dietary regimen. First, there is very little variety. A chickadee would be happy eating nothing but sunflower seeds 365 days a year. Of course, they supplement the seed from a feeder with food they get from other natural sources. Many birds are opportunistic feeders. When a particular food is abundant they feast on it. When grass goes to seed, they gorge on fresh grass seed. At the peak of the 17-year cicada abundance, blue jays feast exclusively on cicadas. If scientists from outer space landed on earth at that time and studied jays, they would conclude that blue jays are 100% dependent on cicadas and eat nothing else.
Nutritionists would also warn birds about the amount of fat in their diet. Birds love fat. Suet, for example, is pure beef fat. One 11 oz. cake of pure suet contains 2900 calories, the equivalent of six Big Macs. But birds like it. And birds need calories.
Despite my mother’s misconceptions about birds’ eating habits, she did instill in me reasonably good eating habits. I have a hardy appetite and I don’t pick at my food. I choose a variety of food from all the food groups and am careful about my fat intake. But my mother still thinks Aunt Helen eats like a bird.
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