Triumph in the Skies: Red-Tailed Hawks Refuse the Quiet Life

Authors: Nick Bergeron, Caroline Brandt, Cristela Ramirez

Urbanization is the way of the future, but sadly it comes at a cost. Urbanization refers to the sprawl of civilization created by developing the land into cities and other human-made areas. Biodiversity around the world is being lost as urbanization fractures and destroys habitats. The red-tailed hawk, with its extensive range throughout North America, is no stranger to the threat of urbanization (1). Red-tailed hawks have mostly thrived despite urbanization due to their ability to adjust to almost any habitat. While they are currently able to adapt, this may not be the case as human populations rise and urbanization continues to convert and fragment natural habitats. Luckily, a host of research and conservation efforts dedicated to red-tailed hawks exists to protect them.

Green spaces!

Within the urban sprawl, green spaces are the areas that retain some natural habitat. A few examples of green spaces are parks, golf courses, empty fields, and large backyards.  The question is: why are green spaces important? Despite habitat loss and fragmentation, red-tailed hawks are thriving in urban areas. Their home ranges are even smaller in these urban areas compared to rural areas, suggesting that urban areas are acting as a higher quality habitat (2). That might seem counterintuitive, but green spaces play an important role in this. They provide food resources, refugia, and pockets of natural habitat. The size of red-tailed hawk home ranges is directly related to the amount of green space within their home range. Interestingly, their home ranges are smaller when the green spaces are more fragmented, this is likely because larger green spaces are heavily developed, while smaller patches are left more natural as they are not as profitable to develop (2). The components that dictate the home ranges of red-tailed hawks are complex and green spaces are only one part, more research needs to be done to fully understand them. Although red-tailed hawks are thriving in urban environments, their success does not come without issue.

In the Sky: A light at the end of the tunnel!

Red-tailed hawks often fall victim to aircraft collisions. In fact, they are one of the ten most frequently hit birds by aircraft in the United States (3). Collisions may be dangerous and even fatal at times for humans and hawks alike. Not to mention, aircraft groundings due to these collisions result in economic losses in millions of dollars every year (3). Aircraft currently lack means for repelling red-tailed hawks and other birds.

Research within the last 50 years explores lights as deterrents for birds. New research points to short wavelength LED lights as the key to deterring birds in flight from aircraft and other areas that may endanger them. Birds can see into the violet and ultraviolet portions of the UV spectrum, some of the shortest wavelengths of the light spectrum, much better than the human eye (3). Results of experiments with short-wavelength LED’s look promising; the red-tailed hawks showed clear avoidance from them (3). The effectiveness of LED’s is good news for humans and birds.

Compared to lasers, a previous candidate for avian-avoidance strategies, LED lights are very low-hazard for human eyes. By using these lights on planes and runways, we may reduce collisions, keeping hawks and humans safe. The LED’s may also function well on mobile units to deter hawks from colliding with tall buildings, cell phone towers, and large-scale power generation plants (3). Biohazardous areas like oil spills and reservoirs for toxic waste may use LEDs to keep hawks from living there too (3). The technology of LED’s is continually evolving, becoming a more reliable and cost-effective tool, especially in the future of protecting red-tailed hawks.

Navigating the Industrial Dangers of Urbanization

It looks as if red-tailed hawks are not ready to leave the city, and measures can be taken to protect them from hazards presented by continuing urbanization and industrial development. As local human populations increase, so does the demand for conveniences such as electricity. Yet, live electrical wires pose a threat to birds and without protection, more raptor deaths than anticipated may continue to be seen (4). Local governments tend to impose safety risks by continuing to allow exposed wires to hang low. The risk of electrocution can be reduced by installing high sitting pylons - or posts where the wires are organized and attached for distribution. High sitting, protected pylons have reduced the amount of demised feathered friends of any stature - raptors or otherwise- by the hundreds (4).

Other sites of energy collection are coalbeds, where methane extraction takes place. As more land is allocated for these sites of extraction, natural habitats continue to be fragmented. The difference between these spaces being used for housing or business development as opposed to energy development is that red-tailed hawks do not want to nest near these disturbed coalbeds (5). A study that focused on a coalbed methane extraction site revealed that nesting raptors became displaced from the area as development continued. The nesting period is a critical time for the raptor, and industrial energy development near its nesting site affects its ability to be fertile (5). Without the protection of these natural habitats and nesting sites, red-tailed hawk populations may be negatively affected. 

Conclusion

Red-tailed hawks’ futures look hopeful, as long as we consider their needs as urbanization continues. Smart city planning, with lots of natural green spaces, and protection from hazards, can help supply habitat and food sources for urban hawks. We can significantly reduce their fatalities from aircraft collisions with the help of short-wavelength LED lights by putting them on aircraft and airfields, and these lights may be used to keep the birds out of harm’s way in other unsafe urban areas. Being sensible about the energy we use and having a citywide plan to safely seek those resources is another important step in protecting these hawks. Urbanized areas will never compare to nature’s ability to provide for red-tailed hawks, so we must continue to conserve what natural habitat is left within and outside of our cities. Feeling inspired to get involved after reading this? There are some simple things that anyone can do to help red-tailed hawks and other wildlife. A great way is to advocate for the creation and preservation of natural habitat within your local communities. Another is to elect officials who understand the importance and value of conservation. With a little effort, urbanization does not have to be a death sentence for wildlife and biodiversity!

Photo Credit

Photograph of a red-tailed hawk soaring with the moon in the background-Credit: By Mike Baird from Morro Bay, USA - Red-tailed Hawk with moon over Estero Bay CA - composition red-tail-moon-composite-2630s, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=32354021

Photograph of downtown Chicago-Credit: Public Domain, https://commons.wikimedia.org/w/index.php?curid=143884

Citations

1. Preston, C. R. and R. D. Beane (2009). Red-tailed Hawk (Buteo jamaicensis), version 2.0. The Birds of North America (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.52
2. Morrison, J. L., Gottlieb, I. G. W. & Pias, K. E. Spatial distribution and the value of green spaces. Urban Ecosystems 19, 1373-1388 (2016).     
3. Foss, C. R., Ronning, D. J., & Merker, D. A. (2017). Intense short-wavelength light triggers avoidance response by Red-tailed Hawks: A new tool for raptor diversion? The Condor, 119(3), 431–438. https://doi.org/10.1650/CONDOR-16-230.1
4. Demeter, I., Horváth, M., Nagy, K., Görögh, Z., Tóth, P., Bagyura, J., … Harness, R. E. (2018). Documenting and reducing avian electrocutions in Hungary: a conservation contribution from citizen scientists. The Wilson Journal of Ornithology, 130(3), 600. doi: 10.1676/17-031.1  
5. Carlisle, J. D., Sanders, L. E., Chalfoun, A. D., & Gerow, K. G. (2018). Raptor nest–site use in relation to the proximity of coalbed–methane development. Animal Biodiversity and Conservation, 41(2), 227–243. doi: 10.32800/abc.2018.41.022