Are You the Cause of Your Favorite Animal’s Death?
The world as we know it is coming to an end. Humans are growing and wildlife is shrinking. We often do not realize the effects of our daily actions on wildlife. Wildlife is important for the overall health of ecosystems and changing the behavior or survival of the organisms will be detrimental for the entire ecosystem. Wildlife contributes to the main resource production in the world by promoting healthy and productive land and marine ecosystems. These places on earth allow humans to have what they do including lumber for houses, food to put on the table, and money in the nation’s economic system. Over 600 species have gone extinct as a result of humans, and that is only including vertebrate species. Without the animals surrounding us, the lives of humans will have to change dramatically. The expansion of humans, tourism, and climate change have shown the greatest impact on wildlife from humans ultimately changing the animals’ behavior and death rates.
The Beginning of the End
Beginning over 7,000 years ago, agriculture was first invented marking the first time where land was being modified for human benefit, however, it wasn’t until the industrial revolution in the 1700s where we saw an extensive increase in land modifications. In a study done by Hooke in 2012, it was calculated that as of 1995, 43% of the land had been altered by humans. As a result, wildlife has less available land to live in. Examined by Bateman, wildlife has a natural response to threats which is known as fight or flight. When the fight or flight response is triggered, stress is increased and behaviors such as feeding, and reproduction are changed as well. Research done by He concluded that as a result of the human expansion onto wetlands, a diverse hotspot for wildlife, a high amount of stress occurred on the wetland area as well as wildlife living within it.
Lockdowns for Humans, Paradise for Wildlife
The COVID-19 lockdowns around the globe allowed researchers like Rutz to see the true effects of humans. Unexpected sightings of nocturnal wildlife that normally would be sleeping during the day came out into neighborhoods and highways. Surrounding humans were in awe to see such rare sightings but little did they know that they were the cause of the animals going in hiding. While some animals were seen more often, wildlife that is reliant on humans for food scraps were seen less often such as rats and gulls since there was no longer a food source to eat. Shannon concluded that a possible cause of the wildlife staying away from urban areas is noise pollution.
Noise pollution includes traffic noise, construction noise, and general human noise which can interfere with the wildlife’s ability to hear sounds such as mating calls. Many species of wildlife communicate through sounds. Birds are largely affected by noise pollution. When zooming down the highway or making extra noise in your backyard, people aren’t thinking about how the birds are being affected. When the noise reaches the habitats, birds and other animals such as frogs, monkeys, and marine animals such as dolphins cannot communicate effectively. Blickley has observed this in reproduction and pairing success in wildlife. Their research concluded that increased noise levels cause a decrease in the overall ability to have offspring. As a result, the population decreases. General human presence affects wildlife by changing their spatial-temporal scales which include the movement and overall change in the wildlife when weather, or climate, changes. This is seen when animals start to sleep more during the day to avoid humans, becoming nocturnal. This way the animals will not be near humans during the day. Examined by Gaynor, mammals did not come out during the day 83% more often to avoid humans. By doing this the animals do not have to interact with dangers such as hunting or transportation killings.
Lighting in urban areas is common to see at night, however, the unnatural light affects the daily activities of wildlife. For example, McLaren put wildlife to the test to see if the lights for humans affected the animals. Animals such as birds were seen crashing into large buildings because they were attracted to the bright lights and the reflection of the buildings confused the birds. Most humans love viewing baby animals, it’s in our instinct. Sea turtle hatchlings are a highly valued attraction; however, the flashlights and neighborhood lights distract the baby sea turtles. Sea turtles, once hatched, follow the moonlight to the ocean but other light sources can affect that travel path. Thums’s research study showed that the human-induced light attracted the turtles more than the moon. When the baby turtles do not make it to the ocean, they are at risk to be eaten by other animals. Most neighborhoods are filled with bird feeders to attract local birds into their yards to view. Good intentions are seen, however, the lack of education behind feeders causes bad effects on the birds. Birds migrate to get more resources during the winter, however, if the birds do not see a lack of food, they will be delayed in their migration routes resulting in the possible death of the animal which is also seen in McLaren’s research.
Pesticides are used by farmers to get rid of unwanted animals and pests that decrease their amount of product they get out of the harvest. The chemicals that are inside pesticides are what truly harm wildlife. Usually, pesticides are used for insects and animals that eat the crops on farms and while it affects the animals that are targeted by the farmers, so are other animals that eat the targeted animals. Berny’s research discovered a decrease in offspring survival when they were exposed to insects that were treated with chemicals, as well as Helfrich seeing effects in aquatic animals when the chemicals run into water sources near the treated area.
Support or Devastation?
An activity most people aspire to do, travel. Visiting the world and the different attractions each place offers is a goal for many people. Specifically, over the past 25 years, the tourism industry has grown by 400 million people with 40% of those attractions involving wildlife. Conservation tourism often donates money to the protection of wildlife through tourist activities, however, are those good intentions causing a worse effect on the wildlife? Through the process of feeding animals, taking pictures, or going into their habitats, we are putting more stress on the animals. A stress hormone called cortisol is found in the fecal matter of animals when there is a high amount of stress in the body of an animal. Studying the stress levels of elephants, Szott found that the cortisol levels were 112% higher in tourist locations than in elephants that did not have human interaction. Similarly, to humans, in response to stress animals’ immune system is suppressed making them more susceptible to disease. To get up close and personal we as humans enjoy feeding wildlife to get a glimpse of their reality, however, the animals can become dependent on humans for food weakening their abilities to compete in the wild. Trekking through the wild by foot or by car to reach the wild animals destroys the habitat and with tourism, a year-round industry the people come non-stop. With the traffic of people, reproduction of the animals is affected because of the amount of stress the animal’s experience, and considering the fight or flight response, the mother can end up abandoning their young putting them at risk for death as seen in Oviir’s research.
Hot Topic
A hot topic in the world today is global warming. The planet warming as a result of greenhouse gases such as carbon dioxide, methane, or nitrous oxide being trapped in the atmosphere. This prevents the heat generated from the gases to escape back into space resulting in the earth becoming warmer. Weather patterns such as droughts, changes in temperature, flooding, and other extreme weather occurrences happen as a direct result as NASA states. This causes the wildlife to have to adapt much more quickly than ever before as a result of human behaviors when we burn oil or coal releasing the gases into the air. In Bucholz’s research, they measured how well animals can adapt to climate change. Kangaroos began panting like dogs while birds began taking baths in water to cool themselves from hot temperatures. Animals also began to move to cooler locations rather than forcing extreme changes in behavior. The metabolism of some of the wildlife changed to support the new environment.
That’s Trashy
Pollution such as physical debris or chemicals can get into the animal’s moths by them thinking it is food leading to choking or digestive issues. A major chemical that enters the ecosystems is lead which is caused by burning oil in factories. Over 15 million animals die each year from lead exposure from ingesting it or eating another animal that has been exposed by it according to Sabate. Plastics is a major concern regarding sea life, specifically sea turtles. Fundraisers, petitions, and policies have been set in place to reduce the number of plastic straws from getting into the ocean. In Wilcox’s paper, sea turtles mistake plastic particles for jellyfish which are a major part of their diet. Consuming plastic often kills sea turtles as well as many other marine species.
What Now?
People around the world have a special place in their hearts for animals, yet they do not take into account their daily actions to fix the problems. The growth of the human population is causing a devastating loss of wildlife species that we all know and love. Understanding the effects that humans have on wildlife will allow us to become better human beings and ensure a better future for the wildlife that surrounds us daily as well as humans.
Literature Cited
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