Released July 11, 2008

LINCOLN, Neb. — Anyone who claims that humans invented music hasn't heard "Frog Calls of Nebraska," a CD compiled by University of Nebraska-Lincoln herpetologist Dennis Ferraro. Each of the 11 musical tracks – one for each species native to Nebraska – has rhythm, melody and meaning.

Among frogs, all the vocalists are male. Females don't have the ability to produce sound, explained Ferraro, a UNL Extension educator on faculty at UNL's School of Natural Resources. The lyrics, like much of our own pop music, are all about finding a mate. The simple bass line translates to, "I'm here in my territory," while the more elaborate, higher-pitched melody is, "Come over ASAP!"

The CD is $10 at Nebraska Maps and More, on the ground floor of Hardin Hall at 33rd and Holdrege, and on the Web at http://nebraskamaps.unl.edu. Maps and More will donate copies of the CD to libraries and nature centers around the state. A sample is available through SNR's Web site, http://snrs.unl.edu/

Most of the recordings are 1 1/2 to 2 minutes long, and they tend to be performed by smaller groups. The distinctions Ferraro wants people to hear were lost in larger groups.

Why learn frog songs?

"Some people who are interested in nature enjoy listening to frog calls when they're relaxing," Ferraro said.

In addition to the aesthetic benefit, people who are familiar with frog calls can help scientists track populations. Thin-skinned amphibians are particularly vulnerable to changing environmental conditions, so population declines or shifts can serve as an early indicator that something is amiss or changing in an ecosystem.

"Amphibian decline is a global problem," Ferraro said. In fact, zoos around the world are recognizing 2008 as The Year of the Frog, to focus attention on the problem of amphibian decline.

Listening to frog calls helps scientists track populations. "Sometimes frog calls are the only way to identify populations, because frogs are secretive and hard to find."

Herpetologists resort to surveillance equipment to track elusive frogs. They place waterproof recording equipment – "frogloggers" – near a pond or wetland overnight, and program it to record for two minutes every hour.

After people learn to distinguish the grumbling of the Plains Spadefoot Toad from the cheery whistling of Woodhouse's Toad, they can go report which species they heard at Reptiles and Amphibians of Nebraska, which goes into Ferraro's database of frog "sightings."

In one example of frog population shift, Ferraro said that over the past 25 years, one Nebraska species, the Plains Leopard Frog, has expanded its habitat to the north, overtaking the habitat of the Northern Leopard Frog.

"Frog Calls of Nebraska" is the latest contribution to a well-established genre. The U.S. Geological Survey initiated Frogwatch USA as a citizen science initiative in 1998, and turned it over to the National Wildlife Federation in 2002. A full catalog of frog calls is online at http://www.nwf.org/frogwatchusa/content_sounds.cfm.

And what do the female frogs think?

Female frogs appear to prefer males with louder, more intense calls, Ferraro said. The calls are also how female frogs recognize males from their own species, which is necessary if reproduction is to succeed.

Males may mate with one or more females in a season. In most cases females expel eggs from their bodies as males deposit sperm onto the eggs. In all but a few cases outside of Nebraska, that is the extent of parental involvement with either the offspring or each other.

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http://ianrnews.unl.edu/static/0807110.shtml

Contacts: Dennis Ferraro, (402) 472-8248

Kelly Smith, (402) 472-3373