(CNN) Just a couple of months after Neal Matthews and his wife moved to their home on a small lake in Tucker, Georgia, an injured goose showed up in their backyard.
"The goose was ensnarled in fishing line. Its leg literally had a big knot around it and it was having trouble walking," Matthews said.
The couple spent days trying to catch it without success -- watching as its walking got worse. That's when they found out about AWARE Wildlife Center, a nonprofit hospital for injured and orphaned native Georgia wildlife just outside Atlanta.
Matthews got advice on how to capture the goose using a net gun they loaned him. Back home, he pushed a button and the net shot out -- covering the goose so it couldn't fly away.
"My wife and I put a towel over it. We carefully untangled the net and put it in a box, closed the lid and drove it to AWARE."
The staff operated on the goose and Matthews brought it home the same day.
"When we saw it fly back to its flock and we knew that we helped it carry on its life -- it was just a moment of gratitude that we were able to do something."
That was 15 years ago and since then, Matthews said, they've rescued "probably three or four geese, a duck, several turtles and the occasional possum or two -- bringing them to AWARE for help.
Millions of wild animals are killed or injured every year in the US due to human causes -- from traffic, to habitat destruction, to poisonings.
Many animals are killed by vehicles alone every year, according to the US Department of Transportation, including slow-moving animals like turtles who try to cross a road to reach mating or nesting sites on the other side.
It's the most common cause of injury for animals coming under the care of AWARE.
But there's something you can do about it.
"People throw food waste out the window. Whether it's a fast food wrapper or biodegradable food, it brings small animals to the side of the road and then larger animals come to try to get the smaller animals and they get hit," said Scott Lange, AWARE's executive director.
"The number one thing you can do to help wild animals during your day is don't throw food waste out of your car."
They also see a lot of water birds end up like the goose tangled in the fishing line.
Without help, birds eventually starve to death because they are unable to swim, fly and feed.
"It's very important that we pick up our fishing line or use biodegradable (line)," said Marjan Ghadrdan, director of animal care at AWARE.
Rat poison and pesticides are another huge problem for the entire wildlife food chain, said Lange.
Lange urges people not to use pesticides on their lawn or leave out rat poison.
"We have had hawks and owls and all sorts of other animals come in that have been poisoned because they eat a rat that has been poisoned."
Keep your cats indoors. They eat rats and mice and are voracious hunters of birds, squirrels and chipmunks. "As much as we love them, they are hurting the wildlife," said Ghadrdan.
Some estimates show domestic cats in North America kill from 10 to 30 billion wildlife animals per year.
Limit your use of plastics. AWARE often gets wildlife stuck in packaging, from six-pack plastic that keeps cans together to potato chip bags.
"Animals put their heads in the bags and they can't get them off and suffocate," said Ghadrdan. "I always cut my potato chip bags so they're not like a little pocket and they can't get their heads inside.
"I think we leave a huge footprint as humans," said Ghadrdan. "I want to do the best I can to try to make a little bit of change."
AWARE has about 100 volunteers and a small staff that took care of some 1,300 animals last year.
"We take all species here. We have hawks, owls, songbirds, snakes, turtles, possums, foxes, coyotes, armadillos, flying squirrels, chipmunks, you name it. We take everything," said Lange.
They perform surgery, feed and medicate them, give them physical therapy or swim time to get their strength back. Ultimately, they try to get them ready for release back into the wild.
And then there are the "unreleasables" whose injuries have left them unable to survive in the wild anymore -- from hawks with broken off beaks to foxes with fractures that healed wrong so they can't hunt.
Those animals become permanent residents of the center and beloved educational ambassadors to the public.
"Getting to look at these animals face-to-face -- see their eyes with your eyes -- it has a real impact on people and understanding how vulnerable they are and how they need to be protected."
If you encounter a a wild animal that is injured or you think needs help, contact a local wildlife rescue organization. To find a licensed rehabber in your area, you can go to the nonprofit Animal Help Now. They will give you guidance on whether to leave the animal alone or safely bring them in for care.
You can also reach out to your local Humane Society or veterinarian who can inform you of local wildlife rehabbers.
AWARE, like many wildlife rehabbers, gets no government funding, relying only on donations from the public.
Neal Matthews doesn't expect everyone to go to the lengths he does to save wildlife.
"You don't have to be the one that runs out and captures the goose that's caught in the fishing line. But perhaps if you take just a second to pick up that fishing line that was left behind -- just by doing that -- you've helped."
He says he feels a lot of responsibility for animals because we are encroaching on their space.
"We're taking their homes to build our homes and they're running out of places to go."