New job for power company: Feeding giraffes
PHILADELPHIA: Some humans consider mulberry trees little more than oversize weeds, but Stella the giraffe loves them.
Her long, grey tongue snakes around the leaves and plucks them from their branches with elegant efficiency.
Stella’s mother, Abby, strolls over for her share, and the Philadelphia Zoo’s two female giraffes quickly strip the handful of branches, consuming approximately a pound of leaves in mere minutes.
Fortunately, the zoo has plenty of the snack, thanks in part to an unusual source: The local power company.
Utility companies routinely trim trees to keep branches from damaging power lines and causing outages, and usually the clippings end up in landfills or are ground into mulch.
But in recent years, a growing number of regional energy providers have begun donating the collected roughage to zoos, whose hungry animals are happy to gobble up the green, leafy tree branches known as “browse.”
Browse partnerships between zoos and power companies are one example of the creative and sometimes unexpected ways zoos work with local organisations to meet animals’ particular - and often enormous - dietary needs. Grocery store chains and restaurants sell or donate greens, fruits and vegetables to zoos, and local land owners, botanic gardens and nurseries also provide plant material.
But utility companies are in the singular position of needing to regularly cut back branches that they cannot use themselves.
From August through October, PECO Energy Co., Pennsylvania’s largest electric and natural gas utility, delivered three pickup trucks full of browse – totalling between 100 and 200 pounds - every week to the Philadelphia Zoo.
The zoo gets browse from several sources, but PECO is its first corporate supplier, and its tree-trimming contractor assigned a dedicated crew manager to coordinate the special deliveries. The cargo was mostly mulberry clippings, with acacia, honey locust and willow mixed in when available.
“The great part about the PECO partnership is the sheer volume of browse it provides,” said Barbara Toddes, the zoo’s director of animal nutrition. “It’s a tremendous amount.”
Zoos require a lot of browse because it’s such an important part of many animals’ diets. Of the Philadelphia Zoo’s 330 species, 40 eat it - from giraffes and giant tortoises to gorillas and little rodents called degus. Browse has it all: Fibre, protein, vitamins, minerals and a little fat. It’s also lower in sugar and higher in protein and fibre than some other plant material, Toddes said.
Chewing on the bark is even good for animals’ teeth.
What’s more, browse provides captive animals with important enrichment and exercise, she said, by giving them new material to play with and forcing them to strip branches of leaves, twigs and bark.
In the wild, giraffes graze on the tops of trees. So zoo staff hang bundles of browse up high to simulate their native environment, which gives visitors a better idea of the animals’ natural behaviour. — WP-Bloomberg