Feeding Bears Like Carnivores Could Kill Them

More proof that bears are omnivores like humans and require much less protein supply than they are customarily fed in zoos is provided by a recent study on the diets of sloth bears and giant pandas.

This means that feeding bears as if they are carnivores could kill them.

Charles Robbins, a wildlife biology professor from Washington State University, explained that bears are not strictly carnivores like cats, which prefer a high-protein diet.

The study's lead author is Robbins.

Whether it's brown bears, polar bears, or sloth bears in zoos, he continued, zoos has always advised to feed them high-protein carnivore diets. When zookeepers do that, the bears slowly waste away.

Experiments and Feeding Trials

Researchers fed captive giant pandas and sloth bears an unlimited variety of foods in separate experiments at various US zoos to observe their preferences, and they then monitored the nutritional profiles of their selections.

To gauge the giant pandas' preference for bamboo, feeding trials with a pair of the animals were carried out in collaboration with scientists from Texas A&M University as well as the Memphis Zoo.

They discovered that giant pandas would choose the more protein-rich and carbohydrate-rich bamboo culm within the woody stalks to the leaves.

They occasionally consumed culm almost exclusively; some up to 98% of the time in March.

The researchers also examined data from five Chinese zoos that had giant pandas in captivity that had successfully given birth to offspring and discovered that they thrived on a diet low in protein and high in carbohydrates.

Six sloth bears were fed sets of unlimited avocados, whey, baked yams, and apples at the zoos in Cleveland, Little Rock, and San Diego.

They ate roughly 88% avocados to 12% yams, choosing the fatty avocados almost exclusively while completely ignoring the apples.

This demonstrated that sloth bears preferred a low-carbohydrate, high-fat diet, possibly resembling their natural diet of termites, ants, and their eggs and larvae.

High-Carbohydrate, High-Protein

Additionally, it differs significantly from the typical high-carbohydrate diet they receive in captivity.

Indian sloth bears typically live only 17 years in US zoos, which is nearly 20 years shorter than the maximum lifespan that can be maintained in human care.

Liver cancer is their leading cause of death.

Previous polar bear studies revealed a similar pattern, showing that captive polar bears, who are typically given a diet based on high-protein content, would imitate the fat-rich diet of wild polar bears if given the choice.

In zoos, polar bears typically pass away about 10 years sooner than they ought to, most commonly from liver and kidney disease.

These two illnesses may arise from chronic inflammation of the said organs, which may be brought on by years of eating unbalanced diets.

The current study and earlier ones also demonstrated that captive bears will select foods that resemble the diets of wild bears when given dietary options.

Robbins pointed out that there is undoubtedly the enduring belief that PhD-holding people know a lot more than a brown or sloth bear.

These bears all began their evolutionary process around 50 million years ago, and they are more knowledgeable than us about this aspect of their diet.

The "Bear" Essentials

Robbins added that his team is the first to be willing to inquire about the bears' food preferences or provide for their medical needs.

Robbins has spent decades researching bear nutrition. He founded the WSU Bear Center, the first and only research facility in the US with a population of grizzlies in captivity.

His team of graduate students first began looking into their unbalanced diets while conducting research in Alaska and observing grizzlies consume salmon.

The researchers had hypothesized at the time that the infamously ravenous bears would feast on salmon, sleep, and then wake up and eat even more salmon.

Instead, they observed that after eating salmon, the bears would stray off and spend hours searching for and devouring berries.

As a result, Robbins' lab began studying the diet of the grizzly bears at the Bear Center.

They discovered that these animals put on the most weight when given a combination of fats, protein, and carbohydrates, such as salmon and berries.

Although all eight species of bears, or Ursids, descended from carnivores, they have evolved to consume a variety of foods, which has allowed them to spread into more places by avoiding direct competition with local carnivores.

It simply opens up a plethora of additional food sources instead of just being a pure, high-protein carnivore, according to Robbins, Phys Org noted.