A Lack of Animal Poop Is Causing a New Environmental Problem

If you haven’t already heard, the world’s animal population is down 50 percent from what it was just four decades ago. The declining animal population is not only depressing, but poses a lot of environmental dilemmas. One of these big problems that isn’t likely to be discussed in polite circles is the logical decline in animal feces that follows.

I know what you’re thinking – poop? Why in the heck would anyone want more feces around? Actually, animal dung plays a critical role in helping to fertilize the world and supply nutrients to everyone’s diet.

Much like the circle of life, there is also a circle of poop. Small fish eat phosphorous-packed food on the bottom of the sea. Larger fish consume these fish. Coastal birds eat these fish and poop on land. This poop serves as fertilizer for plants that smaller animals eat. Larger mammals eat these critters and poop inland, spreading nutritious fertilizer all over.

With the animal population down, a collaborative team of scientists – from Harvard, Oxford, Princeton, Purdue, Vermont, the Netherlands Institute of Ecology and Aarhus in Denmark – wondered what kind of effect this had on fertilization. By their best estimates, animals are now transporting (and pooping out!) nutrients 92 percent less than they were at the conclusion of the previous ice age.

A big reason for the massive drop-off is the decrease in massive land mammals. The days of dinosaurs and mammoths are long gone, and the biggest animals currently on earth are frequently endangered. It’s not just that larger animals make larger turds – they also tend to cover more ground in their travels. It’s their ability to bring nutrient-filled poops to new environments that make them especially powerful in this process.

Although farmers now keep a sizable percentage of the world’s larger mammals, livestock is not going to fix this problem for a couple of reasons. First, the kinds of food animals are served on ranches aren’t often the most nutrient-packed to begin. Second, and more importantly, these animals aren’t free roaming. It’s the animals who wander and can take their feces to various places – further than fences will allow – that are promoting biodiversity.

The animal that the scientists singled out as one of the most important to this poop process is indeed large, but does not live on land: the whale. Whales consume a lot of phosphorus at the bottom of the ocean, which is easily transported along to land and other animals since they poop on the surface. With whale populations down so much due to human hunting, however, they now contribute just 23 percent of the phosphorus that they once did.

How do we fix this detrimental drop in animal droppings? Short of giving animals laxatives (kidding!), the best solution might be to advocate on behalf of these whales who poop out hundreds of millions of pounds of phosphorus. If we can get their numbers back up, that means more nutrient-packed fertilizer will make its way to land to the benefit of every land creature.

Photo credit: Thinkstock


Mark Donner
Mark Donner1 years ago

The manure from herbivores, isn't comparable to humans. It's just grass and you can be around it. Human sh*t is nasty.

Siyus Copetallus
Siyus Copetallus2 years ago

Thank you for sharing.

Beverly S.
Beverly S2 years ago

Just another way our species is wrecking the intricate workings of Nature.

Jennifer H.
Jennifer H2 years ago

Too bad human poop doesn't work the same. Heaven knows we are full of it and cover the Earth with it. Shouldn't ours be worth something.... (sarcasm intended).

We have made a mess of every type of cycle on this planet.

Paulinha Russell
Paulinha Russell2 years ago

Thank you

D.E.A. C.
D.E.A. C2 years ago

50% reduction?!? This is a problem. I wish you'd chosen a different photo to illustrate, though.

Julia Cabrera-Woscek

OMG! The front photo for the article is .. poopy and anus! LOL

Carole R.
Carole R2 years ago

And again, we have upset the natural balance of things.

Anne Patrick
Anne Patrick2 years ago

The decomposition cycle is so important for putting nutrients back into soil or water for plants. The decline in whale populations threatens the oceans greatly as they fertilize the phytoplankton and mix nutrients while diving. The phytoplankton then become the base to the food chain and remove carbon from the atmosphere...they are also the link to helping solve global warming, to producing the majority of the world's oxygen, as well as being the farmers of the ocean. We need to do all we can to allow ocean stocks of all mammals and fish to return to much higher levels.

Sandra Penna
Sandra Penna2 years ago

interesting, thank you.