The Pittsburgh Zoo and PPG Aquarium houses more than 4,000 animals and hosts thousands of visitors each year. A lot of resources are needed to keep the animals fed and comfortable in their habitats, and to keep the grounds looking good – that takes a lot of energy and creates a lot of waste.
Zoo officials are trying to maintain the facility in the most environmentally-friendly way possible – a trend that’s spreading among zoos across the U.S.
Walking around the Pittsburgh Zoo, one thing is clear – the kids are there for the animals. Groups of elementary school children are marveling at the tigers, lions, flamingoes, and even a duck that’s hanging out in the flamingo enclosure.
They are not overly concerned with how much energy it takes to keep the animals healthy and happy, or what happens to all of the waste produced by the animals and visitors. But that’s something that is on the mind of Margie Marks. She’s the Curator of Conservation Education for the zoo.
“It is kind of tricky for a zoo to be green as possible, we’re dealing with animals that either need to be warm, need to be kept cold, all that sort of plays into our animal exhibits,” she said.
You can feel those heating and cooling efforts as you walk through different exhibits. The tropical forest, which houses different kinds of monkeys and other animals, is hot and humid. The water’s edge, home to the polar bears and playful sea otters is cool. Newer technologies allow for more energy efficient heating and cooling, and the technology is getting better all the time.
The Pittsburgh Zoo opened more than 100 years ago, but over the years has, of course, undergone many changes and upgrades.
“The zoo had an energy audit and the zoo started thinking about things as long as 15, 16 years ago to make sure the zoo was walking the talk, to make sure we were doing the right things too,” said Marks.
There’s one thing they can’t change though – the fact that each of the 4-thousand-plus animals produce their own waste. But there is a program for that.
“All that organic waste is taken out of the zoo. Some zoos have a big enough layout, footprint in their own institution that they can compost in house. We do not have that luxury because of elephants and hoof-stock – lots of waste being produced, we actually contract with a company called AgRecycle and they come and pick it up,” said Marks.
Some of that composted material comes back to the zoo in the form of fertilizer.
Visitors see the efforts of zoo gardeners pretty much everywhere they look in for form of lush gardens and forest areas. There are some unseen areas as well. Standing atop the water’s edge, you don’t even realize you’re on a roof.
“This whole complex, this water’s edge complex which encompasses the polar bear, sea otters and right now we have sea tiger sharks, this whole area was designed keeping conservation in mind, so what an appropriate thing to have – a green roof,” said zoo gardener Susan Pearce.
It looks like a well-tended garden.
“One of the benefits of a green roof is they insulate the buildings they’re on top of so it keeps it warmer in the winter, so it saves on heating costs, and cooler in the summer so it saves on air conditioning costs,” added Pearce.
When it rains water runs off nonporous surfaces like roofs and roads, and into sewers and the rivers, but with a green roof, the water stays were it falls.
“Anywhere from 60 to 90 percent of the rain that falls in a rain storm is absorbed into the plants, into the soil, it really helps to prevent erosion on hillsides and flooding, the rivers flooding and washing all the pollutants into the water which affects the water quality and also fish and aquatic life,” said Pearce.
There is another, smaller, green roof atop the Amur Leopard exhibit. There is also a rain barrel there, which collects rain to be used later to water plants.
Other greening efforts are underway throughout zoo. There is an ongoing campaign to replace all lights with either LED lights or compact fluorescent light (CFL) bulbs. More than 500 bulbs were replaced last year alone.
“It’s something that has started and will continue and only get better. We’re hoping to spearhead some wind turbines, solar efficient products and things like that, so that’s something that’s in the zoo’s future,” said Margie Marks.
But the kids walking around the zoo don’t notice the rain gardens, or rain barrels, and Marks said that’s key – making sure the zoo is as green as possible without taking anything away from the experience, in some cases green efforts enhance the zoo experience.
Conservation efforts are being implemented and sustained at zoos across the U.S. Pittsburgh still has a ways to go in taking the top green spot. Marks said the Cincinnati Zoo is considered the greenest, though the Denver Zoo also claims that distinction.