My thesis at Columbia University and why I think it’s so important
Stop whatever song you are listening to on Spotify… What do you hear? For most of us, we hear the sound of tires on the pavement, the honking of horns and the acceleration through a yellow light or the slamming of breaks. And, especially in New York, it’s constant. There is never a day where there is a break from the traffic and the noise from these roads. In fact, road development is one of the most spatially extensive sources of anthropogenic noise and is directly related to the increase of human populations [Barber et al. 2009]. Chronic noise exposure, such as vehicle traffic, is annoying while we try to sleep or block out its frustrating distractions, but it can also cause negative physiological responses to us [Barber et al. 2009]. This doesn’t just apply to humans but also to wildlife. Studies have found that chronic noise exposure has significant impacts on birds, small mammals and cetaceans, including affecting communication and physical deterioration. Even though road ecology and its effects on species have been researched, the majority has focused on birds, amphibians and cetaceans, and few studies have focused on large terrestrial mammals, and those that have merely focused on North American wildlife [Barber et al. 2009]. More specifically, even fewer studies have looked at large African terrestrial mammals.
Now, why is this an issue? Or, rather, why is this more of a pressing issue than other species affected by vehicle noise exposure? Africa, according to researchers at Yale, Texas A&M and Boston University, is predicted to have the fastest urban expansion between now and 2030, growing at 590% [citation]. As human populations and road infrastructure grow, so do the number of human-wildlife conflicts. South Africa’s economy and infrastructure has increased significantly in the last decades, resulting in previously conserved land now being used for human settlements. Before excessive road development continues it is critical to understand the impact of vehicle noise pollution in order to combat possibly detrimental effects on wildlife and local communities.
Wildlife have different reactions to noise exposure, and African species are no different. The wildlife has varying degrees of sensitivity to disturbance [Vanthomme et al. 2013]. Some species, such as the white rhinoceros (Ceratotherium simum) and the African elephant (Loxodonta africana), will avoid areas of high human disturbance such as roads and highways [Buk & Knight 2012]. Animals with a greater tolerance to disturbance, such as the lion (Panthera leo) and cheetah (Acinonyx jubatus), may become habituated to roads and use them to their advantage in order to move from point A to point B in an effective manner [Coffin 2007] . All four species rely heavily on their hearing in order to survive, either for hunting or to avoid danger. As development continues to expand throughout Africa, and especially South Africa, wildlife in small, protected areas are becoming surrounded by roads, and these roads are becoming more frequently used. Animals with less space to utilize within the reserve are having constant, forced exposure to chronic noise from commuting vehicles. Imagine relying on your hearing in order to find your food, but you are constantly listening to honking horns and the hustle and bustle outside of your house. It’s going to make it harder to find that food, don’t you think? Other wildlife populations exposed to noise pollution have had such effects such as hearing loss, hypertension and elevated stress hormone levels.
Not only is exposure to vehicle disturbance negative to African mega-fauna, but wildlife populations and human relations are interlinked. Negative impacts to wildlife can result in economic loss for property holders, social tensions and fragmentation in affected areas and communities, and physical harm and/or death to both humans and wildlife.
So what I am going to do about it? Well that’s a great question! I will be using the data collected between 2006-2013 on a small private game reserve in South Africa and using spatial models and analyses I will determine the impact noise disturbance on lions, cheetahs, elephants and rhinos based on habitat preference and utilization. I will also be going back out to South Africa this summer and determine the distance and impact which noise negatively impacts these animals.
The research will provide vital information about the future of small, protected areas and quantify the true role human development has on large mammals. If species avoid roads due to vehicle noise disturbance, conservation measures must be taken to prevent further human-wildlife conflict and address infrastructure expansion near conserved areas. This will improve development around conservation areas in South Africa as well as contribute to refining areas surrounding protected areas all over the continent, and even the world.
Once the known impacts of noise on large African wildlife are determined measures can be taken to mask these negative impacts. It is impossible to prevent environmentally-irresponsible infrastructure and human-wildlife conflict without knowing its effects first. This project will not only help determine the degree of impact chronic noise has on the focus species, but also provide insight to the optimal habitats to foster sustainable and ecofriendly infrastructure. This will include determining various masking techniques to help dissipate noise disturbance.
Conflict cannot just be interpreted when opposing parties have equal strength and destruction, but rather when at least one party has a significant and detrimental effect on the other, even when the opposing party cannot retaliate in kind. Development expansion exacerbates human’s deleterious impact on wildlife and therefore the impacts of noise pollution on large mammals needs to be explored. Human-wildlife conflict, and the serious detrimental effects that cause it, must be further surveyed not only to preserve wildlife species but also in order to find a solution for humans and wildlife to co-exist peacefully for future generations.
And don’t worry (I knew you would be) but I’ll be sure to keep blogging as I conduct all my research. I’ll probably be writing even more blogs while I’m out there, because it’s much more fun to be writing about the snake I found in my bed or the amazing hyena encounter rather than a post about how Butler Library’s internal architecture is phenomenal (even though, lets be honest, we all know it really is).
Barber, Jesse et al. 2009. “The Costs of Chronic Noise Exposure for Terrestrial Organisms.” Trends in Ecology & Evolution 25 (3) (March): 180–9.
Vanthomme, H., et al. 2013. “Distribution of a Community of Mammals in Relation to Roads and Other Human Disturbances in Gabon, Central Africa.” Conservation Biology: Journal of the Society for Conservation Biology 27 (2) (April): 281–91.
Buk, K., and M. Knight. 2012. “Habitat Suitability Model for Black Rhinoceros in Augrabies Falls National Park, South Africa.” Southern African Wildlife Management Association 42 (2): 82–93.
Coffin, A. 2007. “From Roadkill to Road Ecology: A Review of the Ecological Effects of Roads.” Journal of Transport Geography 15 (5) (September): 396–406.