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Dogs -

Canines are expert sniffers. And some are specially trained to sniff out certain at-risk plant and animal species. This way, researchers can carefully keep track of the population numbers for these organisms.

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Beavers -

In the 1800s, beavers were almost hunted to extinction. Luckily, their numbers grew, as their gnawing and damming behavior have many benefits for our planet. They help prevent floods, droughts, and forest fires.

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Bees -

Bees help pollinate plenty of plants, keeping our environment rich and thriving. They're also great detectors, too. Bees have been used to locate abandoned but still active land mines. They are also used as indicators of when toxic chemicals have been released in an area.

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Llamas -

How can you not love llamas? Not only are they adorable, but they're also great farm animals with a low environmental impact. They eat invasive weed species and, compared to other animals, they won't damage grass.

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Butterflies -

Not only are these winged critters nice to look at, they also help pollinate a number of plants that depend on their feeding habits to survive.

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Sharks -

Sharks might have a bad reputation, but these predators are always helping us out. They feast on weak, old, and sick fish, which prevents disease from spreading among marine life. By doing this, sharks help with biodiversity.

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Squirrels -

You can thank forgetful squirrels for the existence of a few trees. Every year, they stash nutty food supplies around yards and forests. However, squirrels won't remember everywhere they stored food, allowing nuts to grow into trees.

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Rats -

In many countries, rats have been trained to sniff out land mines and bombs left forgotten. Not only are they cheaper to use than dogs, but they also learn quickly, with an impressive success rate.

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Bats -

Feared by many, this creature is actually helping save the Earth. Bats are experts at slaying insects, eating hundreds every hour. This helps control bug populations and protect crops.

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Seals and sea lions -

Seals and sea lions are being outfitted with monitors so they can obtain data from areas of the ocean that are hard for humans to reach. The monitors, which fall off as the animals molt, help scientists understand effects of climate change and ocean circulation patterns.

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Frogs -

As frogs like to slurp down bugs, they've become crucial for controlling the insect population. They're also a good barometer of water quality, as they'll suffer or die when waters are contaminated.

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Ants -

These tiny but mighty insects are crucial to the Earth's soil. They keep our ecosystems in balance and help to clean up rain forests. For example, when they dig tunnels, they aerate the soil and recycle nutrients. This provides a rich, healthy soil for plant growth.

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Horses -

By acting as a natural fertilizer, horses have an important role in plant diversity. As a result, they can positively influence the biodiversity of both plants and animals.

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Birds -

From seed dispersal to plant pollination, birds play an essential role when it comes to the Earth's survival. They also help with insect pest control when they eat bugs, and act as bio-indicators for the ecosystem.

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Narwhals -

Just like seals and sea lions, a group of narwhals has been outfitted with temperature monitors. This way, these sea "unicorns" have been able to provide information about how cold and deep the sea truly is.

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Elephants -

One of the most intelligent species on Earth, elephants use their tusks to dig for water during dry weather. This also provides water for other animals in their shared habitat.

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Fish -

Fish excrement helps the oceans' climate. As they ingest a lot of salt water, they produce calcium carbonate in their excrement. It then dissolves when it reaches the surface, counteracting the carbon dioxide. This reduces the acidity and creates balanced chemical levels of the ocean water.

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Primates -

Our closest relatives in nature, primates disperse seeds as they eat fruits in the forest and fertilize the soil. This helps prevent the erosion of soil in our rapidly disappearing rain forests.

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Termites -

Termites might be destructive when it comes to your home, but not in nature. These creatures consume decomposing plant matter, such as dead leaves, which in turn helps to recycle ecosystem energy.

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Boars -

Usually, boars are very destructive in their environment, but they're also champions at seed dispersal. Their stiff, bristly fur easily catches seeds as they make their way through forests. This action helps scatter the seeds, creating high levels of plant diversity.

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Octopuses -

When it comes to recycling, octopuses are resourceful creatures. They use their tentacles to create shelter using glass containers, coconut shells, and other debris.

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Rabbits -

When in their natural habitat, rabbits help keep plant life in check. Because they can eat a wide variety of plants, populations of rabbits play an important role in keeping fast-growing weeds from overgrowing.

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Plankton -

We wouldn't have half the oxygen in the world if it not for plankton. They stay close to the surface of the water, where there is enough light for photosynthesis. They also break down organic matter in water and recycle dead organisms.

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Tapirs -

Tapirs eat a wide variety of fruit, leaving behind seeds, which then germinate and grow. This is among the cheapest and most feasible of ways to restore tropical forests.

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Wolves -

Wolves play a key role in keeping ecosystems healthy. They help keep deer and elk populations in check. Also, the carcasses of their prey help to redistribute nutrients and provide food for other species.

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Worms -

As worms burrow and consume soil, they extract nutrients from decomposing matter. They then transport these nutrients to the surface with their excrement.

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Whales -

Whales are saving both land and sea. When whale expel their excrement, which is full of nutrients, near the surface of the water, it transfers to birds. They then carry it to land, serving as a natural fertilizer.

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Pigs -

Another animal that "recycles," pigs will nourish themselves with what people consider waste. If it wasn't for them, these leftovers would be headed for the landfill.

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Goats -

Goats help prevent the spread of weeds, and promote the growth of local vegetative species through moderate grazing. They're also more water-efficient than larger animals, such as cattle.

Sources: (One Earth) (GlobalGiving)

See also: The 30 loudest animals in the world 

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