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Back to School at FROGS ARE GREEN!

Wednesday, August 18th, 2010

It’s back-to-school time and we’d like to introduce you to a few notable children’s books about frogs and other amphibians published recently:

THE FROG SCIENTIST by Pamela S. Turner, photographs by Andy Comins (Houghton Mifflin, 2009)

Dr. Tyrone Hayes, with his children, reads a book his mother gave him as a child, from THE FROG SCIENTIST. Photo copyright Andy Comins.

This book, part of the Scientist in the Field Series, is a biography of frog scientist Dr. Tyrone Hayes at UC-Berkeley, who has done groundbreaking studies about the effects of atrazine, a widely used herbicide, on frogs. While the book is mainly a biography of Hayes, it is also a good overview of the global amphibian crisis and it includes an easy-to-understand explanation of the scientific method. The book has a lively, engaging design and many wonderful photos. It would be ideal for kids who are at that age (around 10 or so) when they decide that “science is boring.”

Dr. Hayes is an engaging subject for a biography, and the anecdotes about him are refreshing for this type of book (which can often be dry). A whole unit could be planned around THE FROG SCIENTIST, covering such topics as a science as a career, African Americans in science, the global amphibian decline, the scientific method, to name just a few.

A PLACE FOR FROGS by Melissa Stewart, illustrated by Higgins Ford (Peachtree 2009).

A PLACE FOR FROGS by Melissa Stewart, illustrated by Higgins Bond

For younger children (@5-8), this nonfiction picture book introduces different species of frogs and places them in their habitats. Each oversized double-page spread features a frogs species, their habitat, and shows some of the ways that human action and interaction can affect frog populations.

For example, one spread describes the Sierra Nevada Yellow-legged frog and its habitat, and explains why adding trout to the frogs ponds caused their decline (the trouts devoured the tadpoles). When people removed the trout, the frog populations began to recover. The frog and its habitat is depicted in gorgeous realistic paintings and is described in easy-to-understand language.

A Place for Frogs could be used for teaching kids about animal habitats (this author/artist team also did A Place for Butterflies and A Place for Birds). It could also be used in a unit about endangered animals, a unit devoted to frogs and amphibians, or it could be read as a springboard to study a local endangered frog in more detail, depending on where the school is located.

Big Night for Salamanders by Sarah Marwil Lamstein, art by Carol Benioff (Boyds Mill, 2010).

Illustration from BIG NIGHT FOR SALAMANDERS by Sarah Marwil Lamstein, art by Carol Benioff

In this narrative nonfiction picture book, a boy waits for the Big Night, the first rainy night in late winter or early spring when the blue-spotted salamanders begin their annual migrations. The salamanders must travel from their forest burrows to vernal pools, where they breed and lay eggs. The problem is the salamanders must cross a busy highway to reach the vernal pools. The boy, along with other volunteers, helps the salamanders cross the road. A parallel text in italics describes the migration of salamanders.

This is a lovely simple story about how one boy helps an endangered species close to home. It is illustrated in richly-colored gouache. At the back is information about the life cycle of blue-spotted salamanders, as well as information about the Big Night and vernal pools.

Big Night for Salamanders would be a good read-aloud book for younger children. It could also be used in units about the life cycles of animals, and about species whose habitats are threatened. Teachers could read this book in the spring and plan a field trip to a local vernal pool.

Don’t forget about the FROGS ARE GREEN ART CONTEST FOR KIDS! Please download and print out this flyer to tell kids about the contest.

Tags: A PLACE FOR FROGS, atrazine, BIG NIGHT FOR SALAMANDERS, blue-spotted salamander, children's art contest, children's books about amphibians, children's books about frogs, children's books about salamanders, Dr. Tyrone Hayes, educating kids about frogs, frog educationa materials, frog units, global amphibian crisis, global amphibian decline, Kids Art Contest, learning about amphbians, learning about frogs, life cycle of the frog, Read about Frogs, THE FROG SCIENTIST, vernal pools
Posted in Frogs Are Green contests, Kids Art Contest, Learn about Frogs, Life Cycle of Frogs, Read about Frogs, Salamanders, Teaching Kids about Frogs | 1 Comment »

Big Chill Helps Mountain Yellow-Legged Frog

Thursday, April 29th, 2010

One of the most endangered amphibians in North America—the mountain yellow-legged frog—might have some hope this spring due to the collaborative work of researchers at the San Diego Zoo’s Institute for Conservation Research, along with the help of biologists at the U.S. Forest Service, U.S. Geological Survey, and the U.S. Fish and Wildlife Service.

Courtesy of UC Berkeley, www.crcd.org

As reported in the Press-Enterprise (Riverside, California), researchers from the San Diego Zoo’s Institute for Conservation Research, which has a captive breeding program for the frogs, discovered that three months hibernation in near-freezing water is what gets these frogs in the mood for love. In the wild, frogs hibernate in icy, high-elevation streams, not in 55-degree aquariums. To mimic these cool temperatures, they were placed in clear plastic shoe boxes called “Valentine’s Day retreats” and stored in the refrigerators.

When they were removed from the refrigerators in April, they displayed breeding behavior within a few days. According to the institute’s Research Coordinator Jeff Lemm, “It has been wildly successful, and as a result, we could reintroduce about 500 eggs into the San Jacinto Mountains.”*

Only 200 individual mountain yellow-legged frogs exist in the wild. Once common in Southern California’s mountain streams, the frog species is almost extinct due to fungal infections, pollution, habitat loss, and predatory trout introduced for fishing. Researchers hope to re-establish wild populations with the captive-bred frogs.

Kudos to students, researchers, and biologists who are helping to save the mountain yellow-legged frog from extinction!

Please see the video below to learn more about efforts to save the mountain yellow-legged frog. This frog species was also featured in the episode Yosemite in the recently rebroadcast PBS documentary The Thin Green Line, about the amphibian decline, which you can watch online.

*As reported on the University of California’s Natural Reserve System site.

Tags: captive breeding programs for frogs, hibernation mountain yellow-legged frog, Jeff Lemm, mountain yellow-legged frog, PBS documentary frogs, San Diego Zoo Institute for Conservation Research, The Thin Green Line, U.S. Fish and Wildlife Service, U.S. Forest Service, U.S. Geological Survey, University of California Natural Reserve System
Posted in Amphibian habitat loss, Frog Conservation, Life Cycle of Frogs, People Helping Frogs and Toads, habitat loss | No Comments »

Vernal Pools: Woodland Nurseries for Frogs and Salamanders

Wednesday, April 7th, 2010

This past weekend, I went hiking with my family in Harriman State Park in New York. We’ve had a very wet spring—well, actually it sometimes seems as if we’ve been living in a rainforest. It’s possible that all this rain will means lots of frogs and toads this summer.

While hiking we found a swamp and listened to a wonderful chorus of spring peepers and (we think) Eastern American toads.

My son Jeremy listening to a chorus of spring peers, Surebridge Swamp, Harriman State Park, New York

My son Jeremy listening to a chorus of spring peepers, Surebridge Swamp, Harriman State Park, New York

We also saw lots of vernal pools, bodies of water that appear in the spring and last from two to three months before they dry up in the summer. Some types of amphibians, crustaceans, and other wildlife need these pools for breeding, hatching eggs, or as a nursery while they are young. Because they are temporary, vernal pools do not contain fish (which eat tadpoles and larvae).

When you hike by vernal pools, they don’t look like much. In fact, my sneakers got soaked as I tried to jump over one. Yet they are of critical importance to wildlife. I’ve noticed, however, a lot of comments on environmental blogs that read something like this, “Only treehuggers would want to save these mud puddles!” Yet wood frogs, some species of salamander, and fairy shrimp need these “mud puddles” in order to survive. Every year hundreds of acres of wetlands are lost (usually forever) to commercial or residential development. According to the Ohio Vernal Pool Partnership

These usually small, but very dynamic wetlands fill with water, blossom with life and host a cacophony of sounds and a plethora of life forms every spring, only to disappear into the forest floor every autumn…. A vernal pool is a place where a good naturalist can weave many fascinating stories about the amazing life forms, adaptations, and life histories of its inhabitants, and demonstrate it by a single swoop of a dip net! Vernal pool is a miniature, fascinatingly complex and fragile world, with all of its drama played out every year close to our homes, and yet most of us have never witnessed it. [Ohio Vernal Pool Partnership].

: Salamanders and woodfrogs migrate from their wintering sites to vernal pools for breeding when the conditions are right, courtesy of The Vernal Pool Association

Here are some sites and articles I’ve found (you can also try putting “vernal pool” and the name of your state in google).

Massachusetts (The Vernal Pool Association)

Ohio

Tags: Amphibian habitat loss, Eastern American toads, fairy shrimp, Harriman State Park, life cycle frogs, life cycle salamander, Salamanders, springer peepers, The Vernal Pool Association, vernal pools, wood frogs
Posted in Amphibian habitat loss, Frog Conservation, How You Can Help, Life Cycle of Frogs, People Helping Frogs and Toads, Salamanders, habitat loss | 2 Comments »

First Monogamous Frogs Discovered

Monday, March 1st, 2010

This past week the first monogamous frogs were discovered in the rainforest of South America. Monogamy isn’t usual in the amphibian world. Male frogs usually love ‘em and leave ‘em.

But Dr. Jason Brown, previously of East Carolina University, Greenville, North Carolina, and his colleagues, discovered a monogamous frog species Ranitomeya imitator, known as the mimic poison frog,

According to the BBC Earth News article, “Peru Poison Frog Reveals Secret of Monogamy,” after mating, a female mimic poison frog lays her eggs on the surface of leaves. After the tadpoles hatch, the male frog carries them one by one on his back to pools of water that collect in bromeliad leaves high up in the branches of trees. Each tadpole is put into its own tiny pool and the father looks after them. When the tadpoles become hungry, the male calls to his female partner who lays a non-fertile egg, which the tadpole eats, in each pool.

Why are these frogs monogamous and others aren’t? Scientists believe the mimic poison frogs have become mongamous as they evolved to live in small pools. The frogs wouldn’t have survived without the care of both mother and father because there is little natural food in these tiny pools. If the pools were bigger, there would have been more available food and the the frogs wouldn’t have to work together to feed and raise the tadpoles.

“These frogs are truly devoted to their offspring, and to each other,” says Dr. Brown, who is now at Duke University.

Father and mother R. imitator frogs guard a leaf pool where the mother just deposited a nutritious egg for the tadpole to eat. Photo by Jason Brown, from Science magazine site

Image from ScienceNOW blog (Science magazine)

Tags: BBC Earth News, Dr. Jason Brown, frogs Peru, mimic poison frog, monogamous frogs, rainforest frog, Ranitomeya imitator, ScineceNOW
Posted in Frogs and the Rainforest, Learn about Frogs, Life Cycle of Frogs, Rainforest Frogs | No Comments »