The state of the environment is a huge problem. Sometimes it's so huge that you might find yourself saying "what can I do"? But this sort of defeatist thinking is going to be responsible for the eradication of thousands of animal species. I believe that it's every individual's responsibility to take ownership of their actions and do what's best for the people and animals around them.
You may not feel like what you do makes an impact. But remember, every flood starts with a drop of rain. Every major political movement started with one courageous person with an idea.