Wood Thrushes have just arrived in our yard in North Carolina, having completed their migration from Central America that began a few weeks ago. Their flutelike singing from the treetops affirms that spring is really here.
Recognizing that it is part of our nation’s heritage, the Wood Thrush is one of about 1000 species that have been protected by the Migratory Bird Protection Act (MBPA) of 1918. Even with that protection the population of Wood Thrush is down about 60 percent from a few decades ago. The species is sensitive to acid rain, house cats, habitat destruction, and collisions with buildings and automobiles.
The Migratory Bird Protection Act was no doubt stimulated by the extinction of the Passenger Pigeon, for which the last individual died in the Cincinnati Zoo in 1914. Even with the protection of the MBPA, North America is estimated to have lost 3 billion members of its avian populations in the past half-century. Many species have lost 20 to 50 percent of their population, with grassland species the hardest hit.
This loss of birds matters. Through observation and field experiments, we know that birds feed on a variety of insects that are harmful to crops and forests. Their loss translates to direct economic losses for humans. Indirectly, birds pump money into local economies through the activity of hunters and birdwatchers, who constitute some of the largest recreational groups in the nation.
Even so, a couple of years ago, at the urging of the oil and gas industry, the Trump administration announced that the U.S. Department of Interior would no longer enforce penalties for incidental killing of birds—only intentional killing. If I were to shoot a Wood Thrush from the treetop, I could be prosecuted under the MBPA. If I were a land developer and bulldozed the woodland for a new treeless suburban development, I would be forgiven if I inadvertently destroyed a few Wood Thrush nests.
Vacating the provisions for incidental death of birds would have exempted British Petroleum from fines associated with bird deaths from the Deep-Water Horizon oil spill and Exxon-Mobil from the Valdez disaster. The argument goes that we must not let birds stand in the way of the economic development of this country, especially the pursuit of energy resources.
Of course, with his aggravating level of thoughtless inconsistency, the President has criticized wind mills for their incidental effects on birds—overlooking a recent analysis by the Ecological Society of America that this source of mortality is rather trivial for bird populations and central to our efforts to mitigate the ongoing changes in climate.
Birds matter. And with proper regulations for their protection and the judicious development of new sources of energy, we can have both for a bright future.
References
Ecological Society of America. 2019. Impacts to wildlife of wind energy siting and operation in the United States. https://www.esa.org/wp-content/uploads/2019/09/Issues-in-Ecology_Fall-2019.pdf
Hames, R.S., K.V. Rosenberg, J.D. Lowe, S.E. Barker, and A.A. Dhondt. 2002. Adverse effects of acid rain on the distribution of Wood Thrush (Hylocichla mustelina) in North America. Proceedings of the National Academy of Sciences 99: 11235-11240.
Karp, D.S., C.D. Mendenhall, R.F. Sandi, N. Chaumont, P.R. Ehrlich, E.A. Hadly and C.C. Daily. 2013. Forest bolsters bird abundance, pest control and coffee yield. Ecology Letters 16: 1339-1347.
Mantyla, E., T. Klemola, and T. Laaksonen. 2011. Birds help plants: a meta-analysis of top-down trophic cascades caused by avian predators. Oecologia 165: 143-151.
Rosenberg, K.V. et al. 2019. Decline of the North American avifauna. Science 366: 120-124.
Rushing, C.S., T.B. Ryder, and P.P. Marra. 2016. Quantifying drivers of population dynamics for a migratory bird population throughout the annual cycle. Proceedings of the Royal Society of London B 283: doi: 10.1098/repb.2015.2846
Thanks Bill for highlighting the example of wood thrushes being impacted by Trump’s pro fossil fuel ad pro development policies. I remember 16 years ago when I first tuned in to their incredibly beautiful melody. While I can mimic the call of cardinals and the call of ravens I can’t come close to duplicating the voices of wood thrush. It brings a smile to my face, a feeling of joy and appreciation for the beauty of spring when those thrushes arrive and settle in.
Thank you for continuing to highlight the impact of human presence on the natural world. It’s important to feel it, to see it, to hear it, to understand it. Then we have reason to care and pull that awareness into how we live — individually and collectively as fellow creatures o this planet.
Birds matter. All birds. So do bats. Yet existing regulations are being ignored by States, especially New York State and California, in order to line the pockets of Wall Street investors in Production Credits and Investment Tax credits for 700 foot tall Wind Turbines in the migratory pathways. If any oil and gas rig causes the death of an eagle the penalty is $1,000,000.00. If Altamont Pass Wind Turbines in California wipe out an entire eagle population, there is prosecutorial discretion and no one is charged, prosecuted, jailed or fined. However much I may disagree with the reduction of protections of birds in regulations, I despise more the double standard of enforcement. It degrades the law, it leads those opposed to the regulations to rightly say that if the rules are not enforced uniformly, then why have any at all.
Lastly, I read somewhere that when the issue of birds dying from wind turbines was raised that the supporter of wind turbines opined that millions of birds are killed every year by feral cats and skyscrapers and that allowing wind turbines to kill more is just another cost of doing business. The same may be argued for the reduction in regulatory protections. Yet that same writer didn’t propose supporting the elimination of feral cats which are an invasive species or a nation-wide ban of skyscrapers. These reductions in regulatory protections for birds are the Karma of the environmental community for adopting a double standard of enforcement by protecting those who agree politically with them from the reality of the consequences of the good laws which we actually helped write in the 70’s.
Bottom line: Keep bird protections in place and declare an open season on house cats–free roaming and feral. I am all in favor.