Park Scientists, written by Mary Kay Carson and photographed by Tom Uhlman. Houghtom Mifflin Harcourt, Thomas Allen & Son, 2014. $ 24.99 ages 10 and up

"A grizzly bear eats any living or dead animal, from bison to ants, as well as feasting on dandelions, mushrooms, grasses and seeds. "Bears are opportunistic omnivores," says Mark. That means they eat pretty much anything they can find."

Three American national parks are included in another in the acclaimed Scientists in the Field series: Yellowstone, Saguaro and  Great Smoky Mountains. While scientists work to manage their natural resources, they also spend time studying the parks themselves.

Since they are all protected places, the work being done can be long-lasting and offers a clearer look at all that keeps them viable and productive. There are many scientists included, and they work together in collaborative projects that impact what we know about the parks themselves. Mary Kay Carson and Tom Uhlman worked with a  geologist, a wildlife biologist, a herpetologist, an evolutionary ecologist, an entomologist and a park biologist. Together they coordinate their projects to make the most of what they are learning:

"Park scientists track numbers of bears, eagles, and sequoia trees. They monitor volcanoes, measure glaciers, and look after caves. Scientists in parks collect weather information, restore habitats, and oversee animal populations."

Their work is very important, and young scientists will be interested in knowing about it. Each section of the book begins with a greetings postcard to welcome you to the park in question, to give you a snapshot of the park itself, and also a list of websites where more information can be found. There are many reasons for visiting these remarkable places.

In Yellowstone, the geysers and grizzlies hold our attention. The welcome to Saguaro National Park suggests that rattlesnakes, hummingbirds, sunsets and huge stands of saguaro cactus provide excellent reasons for a visit. Citizen scientists (like you and me) volunteer to track Gila monsters and measure the famous cactus for which the park is named. Finally, the Smoky Mountains beckon. Here, salamanders and firefly shows attract visitors year after year.

As is usual with this amazing series that spotlights research in so many scientific fields, the writing is conversational and explanatory; the clear, colorful photographs give us a closely observed feel for these wild, protected places. Bravo to those who work so diligently to do the research that makes a difference in the lives of those who read these books, and who encourage each of us to learn more that we ever thought possible.

"There are fireflies with yellow lights, orange flickering lights, white flashbulb lights, blue floating, glowing lights - and ones that don't light up at all. Some fireflies, like the synchronous, don't eat at all as adults, while others are voracious predators that hunt other insects, including other fireflies. Predator fireflies are the one with the bright white popping and greenish flashes."

Now, you know!