I bet you have seen once a group of geese flying over your head in a shape of inverted V. It is probably when they are planning to migrate to a warmer place. Animal Spatial Cognition introduces that bird orientates by using a combination of compass and map sense with most dependence on the sun, stars, magnetic field, and landmark. Scientists have been studying bird for centuries, it is not only because of bird’s contribution to the environment but also bird’s incredible ability of orientation and navigation for both long and short distances. However, as human activities having more impact on the natural, this magical creature is being suffered from climate change.
Bird Migration – photo obtained from Wikipidiea Commons
Climate change affects birds in various ways. Here I only focus on one example of climate change: acid rain.
Acid Rain – An Example of Climate Change
Acid rain is a rain that is acidic. Acidic means its pH is lower than 7. The lower the pH value, the more acidic the rainfall is. Graph 1 shows a downtrend of yearly mean pH rainfall value from 1977 to 2017.
Graph 1. Yearly Mean Rainfall pH Value (imagine created by Tina Sun, with data from Central Weather Bureau)
With rainfall is growing more acidic in more areas, scientists have found that acid rain can change bird habitat by acidifying the water. Calcium, the main element of bones forming, reacts with the acid in the rain. This reaction decreases calcium concentration in water, which may make birds unhealthy since birds need a large amount of calcium for deposition of bone and egg shells.
Also, acid rain can wash out many nutrients from the soil, resulting trees and plants grow slowly or die. Moreover, some micro-organisms that are indispensable for plant life cannot survive under acidic condition. Thus, a decreased number of plant life causes insufficient food resources. Then, insufficient food resources lead to increased trophic mismatches in the bird population. The trophic mismatch is a phenomenon that is due to the unsuitable match of consuming food. Finally, the competition of food resources between resident and migratory birds is unavoidable.
Effects of Acid Rain On Woods – photo obtained from Wikipedia Commons
In my opinion, saving our environment is not only helpful to birds or rest of animals, but it is also related to our own lives as well. The responsibility of improving the environment around us has been announced a long time ago, and it is time for the individual to take an action.
-Tina Sun
