World Environment Day 2020: Ruminants are the key to achieving ecosystem biodiversity
Biodiversity loss is one of the biggest threats facing environmental and human health today. World Environment Day provides us with an opportunity to explore potential solutions to biodiversity loss. One of the biggest tools we have available to us in the fight to enhance and protect our ecosystems is probably one of the most overlooked: ruminant animals.
Ruminants are animals like cattle, sheep, goats, deer, antelopes, and giraffes that have a four-chambered stomach capable of converting forages like grass, brush, and weeds into energy. (Fun fact: camelids like camels and llamas have a three-chambered stomach and aren’t technically classified as ruminants even though their diets are largely the same).
For all the negative attention cattle are receiving these days, it may be hard to view them as an important piece of the biodiversity puzzle. What it really comes down to, however, is how the cattle and other ruminant animals like sheep and goats are managed. When managed appropriately, ruminants are one of the best ways to bring more life to the land.
The United Nations Food and Agriculture Organization estimates that grasslands cover between one-fifth to two-fifths of the planet’s landmass and are home to 10% of human life. Grasslands are suffering, however, from increased human activity. In 2014, a group of scientists published the results of a five-year study performed at 40 grassland sites around the world to see if grazing could reverse some of the biodiversity loss in these grasslands.
The answer? Ruminants proved to be biodiversity champions.
Grazing is a powerful tool
Hundreds of years ago, there were between 30 to 60 million bison roaming America, mostly in the Great Plains. As the massive herds moved throughout the land, they grazed along the way. To keep predators at bay, the herds stayed on the move. As the bison migrated, they grazed along the way, trampling forage into the soil and depositing manure. One they were gone, however, the recently grazed forage had ample time to rest and regrow before the herd returned.
This same exact principle is what many beef producers are already using today on their farms and ranches. There are countless names for it from management intensive grazing to holistic grazing to rotational grazing. In essence, good grazing management involves moving animals to new pasture at an appropriate pace while allowing recently grazed forage time to rest and regrow.
If cattle are given continuous access to an entire farm or ranch, a few negative impacts happen. First, cattle will seek out the grasses they like the most leaving less palatable forages behind. As the preferential forages are overgrazed, they eventually die out and leave ample room for less desirable forages to take over. With less forage present, insects like pollinators and wildlife have fewer places to find food and make their homes.
Overgrazing also exposes the soil, making soil runoff and nutrient loss far more likely. Healthy root systems are key to healthy soil by providing structure to the soil and improving its water holding capacity. Because unhealthy soil can’t support plant life nearly as well as healthy soil, forage won’t grow back as readily after grazing.
Once cattle are moved off of a pasture, the manure they’ve left behind feeds the bacteria and insect life in the soil. Healthy soil is the foundation to every biodiverse ecosystem, creating the foundation for healthy forages. Recently grazed plants are given plenty of time to regrow. Because cattle were moved off of the pasture before the plants were overgrazed, the plants have ample leaf material to perform photosynthesis and regrow. The combination of healthy soil and healthy forages create a balanced ecosystem for not only the cattle but local wildlife and humans, as well.
Sheep and goats are biodiversity mavens, too
Studies have shown that the addition of other ruminants like sheep and goats can take this paradigm to even greater heights. Sheep and goats can be managed using the same holistic grazing principles. Many pasture-based livestock producers often use multi-species grazing to promote pasture health and forage diversity. While cattle tend to prefer grasses, sheep love to eat weeds and goats love to eat browse plants like brush, trees, and brambles. Using these three ruminants in harmony depending on the specific forage base of a piece of land can lead to optimum balance. If the land has an overgrowth of invasive tree species, for example, goats can help keep the growth in check so that other plants, waterways, and features of the property aren’t swallowed up.
In many cases, chemical inputs may be used to spray the weeds and undesirable plants that sheep and goats would devour readily. Some of these chemicals have negative consequences for pollinators and local wildlife as well as implications for human health when runoff carries them into local waterways or they leach into groundwater.
But what if we took cattle out of the picture and simply left these lands alone?
It’s not that simple. Think about what happens to your lawn if you stop mowing it. The same way that overgrazing depletes the soil and makes the land less inhabitable for wildlife, studies have shown that undergrazing leads to stagnation and enables a few dominant forages to take over. When one type of forage is allowed to dominate, it shades out other forages and prevents them from sprouting. The dominant forage eventually wilts or dies off but the residual material can still shade out forages that would have otherwise volunteered had the dominant forage been grazed off.
As cattle graze, the act of eating the forage, trampling it with their hooves, and depositing manure contributes to the regular turning over of the pasture. Grazing off the more mature forages brings light into the canopy and allows other seeds in the soil’s dormant seed bank to volunteer. Whether it is tame pasture, grasslands, or prairies, optimum health for these ecosystems means regular transitions.
What’s the best part about ruminant animals’ biodiversity enhancement services?
Meat. Lots of it.
Studies have shown that holistic grazing practices like the ones described above actually help boost grazing efficiency. When cattle are moved from new pasture to new pasture on an appropriate basis, they graze the available forage more uniformly and end up eating more than they would have if they’d been given access to everything all at once. Because pastures are used more effectively, producers who use these methods can often run more cattle on their land boosting the beef supply they can generate.
So, the next time you find meat on your plate from an animal raised using holistic management rest assured that you’re helping to support biodiversity in a delicious way.