To an unfamiliar observer, the hobby of birding seems just that, a hobby. But from a macroeconomic perspective, careful observation of bird behavior can indicate overall health of an ecological system. “On the ornithological level, it involves more careful observation and critical evaluation of bird behavior and noticing patterns. I’m looking for certain species and seeing what I can find and photographing them. I keep lists for certain reasons, but as I do that, my observations lead me to these patterns that I find interesting,” explains David Tønnessen, UC Boulder ecology and evolutionary biology grad student. He’s already made quite a name for himself in the Colorado birding community. He recorded the first sighting of a tropical king bird in the state of Colorado with his two younger brothers at the Chico Basin Ranch, ironically on the younger two’s first day ever birding. In his own words, it was one of the best days of his life. The species typically lives in Mexico and South America, so the sighting made quite a ripple. Less than three months later, he recorded another first sighting. This time, a red-breasted sapsucker appeared in Colorado Springs, a long ways away from their typical habitat in the forests of the West Coast. David’s two separate first recordings in the state are remarkably impressive. To add to the feat, he recorded both by the age of 20.
“I’ve always been into nature. Before I was into birds I was into insects. When I was six, I would catch caterpillars and tadpoles and watch them, and watch birds and cardinals at my parents feeders in Minnesota, so that sparked my interest in birds. I think what really got me into the more serious aspect or fascination in ornithology was eBird, an electronic database run by Cornell University. It’s the largest citizen science database in the world. You have access to all these charts and range maps based on data from people submitting lists of birds at locations all over the world for free, and that definitely got me started.” David’s initial interest expanded into a calling. He has identified over 700 species so far and plans on creating a career from his passion, ideally in South America. In the meantime, he spends as much time as possible observing birds, often at the Chico Basin Ranch: “The Chico has an incredible diversity in habitats. The cholla grasslands form the northern limit of that species’ range, so a lot of birds that specialize on that plant reach their northern limit as well. But I think really what draws people and birds is that during migration, forest songbirds migrate over miles and miles of barren grassland and reach the Chico Basin Ranch and find these towering trees and water, so it concentrates them, especially this time of year being fall migration” says David. With scores of species of flycatchers, wrens, vereos, thrushes, sparrows, and warblers making biannual pilgrimages over the Chico’s skies, plenty of opportunity exists to pose questions about avian habits.
“Their colors, their behaviors. We’re learning new things about them constantly, like mimicry behavior. We don’t fully understand why species mimic.” One of the more fascinating behaviors observed on the Chico Basin Ranch might be the loggerhead shrike. “That genus of songbirds are the only birds that will eat other birds, reptiles and small rodents. They have this really cool adaptation where they will use thorns, and now that barbed wire is installed all over the country, they’ll stab their prey onto the barb or thorns before they consume it, especially with toxic lizards to neutralize the poison. It’s why they’re also referred to as butcher birds.” David has plenty of stories from his time in the pursuit. The more opportunistic species of jays, crows, magpies, and ravens have learned to equate campgrounds with plenty of food. “They’ll follow you around if you have food. They’ve landed on my head before.”
As David explained, the study of birds is a game of patterns. For example, he assisted in a study of crossbills in the Pike National Forest, a type of finch. Several different types frequent the area, each with minutely different vocalizations. One type preferred the seeds from Ponderosa Pines, while others gravitated towards Lodge Pole Pine seeds. Collecting data on the time needed to crack open specific seeds paired with spectrograms of their vocalizations will hopefully reveal any hybridization, or if the species are truly separate from each other.
Birders’ commitment to noticing and recording these patterns reveal immense amounts about the ecological system, including information about population health of the species being observed. Recently, higher Mountain Plover numbers have been recorded than expected. “A local case: Mountain Plovers breed through the upper central Great Plains, and from cattle grazing and land use we thought we had been destroying their habitat for quite some time. They need really short grass prairie and bare ground to breed, but when we started land bird surveys we found that they adapted to breeding in agricultural land, in tilled soil…whether that’s a result of them rebounding or adapting quickly from the start, we aren’t sure, but we had a lot more than we thought.” It turns out, cattle grazing influences the land in a positive way for many animals, including birds. It undoubtedly contributes to the ideal habitat conditions on the Chico Basin Ranch, but as helpful as ethical land management proves for wildlife, it falls on the next generation to continue observing, learning, and driving conservation efforts to ensure sustainability. The ornithological world has an outstanding asset in David Tønnessen.
