The above is an Ozark Hellbender below is a picture of an Eastern Hellbender.
Both species are native to Missouri and in the past 10-15 years have suffered serious population declines - estimates range from a 60-80 percent drop in numbers.
Yue-wern Huang, an assistant professor of biological sciences at the University of Missouri at Rolla, says there seems to be a reproductive disruption among the salamanders. However, Huang says he's unsure what is causing a disruption in the hellbender's endocrine system, which regulates the secretion of hormones - although his theories include pollution, pesticides and people as possible causes.
Huang hopes water samples from the North Fork will give him insight into what pollutants might be harming hellbenders.
At Southwest Missouri State University, associate behavioral ecology professor Alicia Mathis is also trying to help keep the salamanders from extinction. Mathis and graduate student Shem Unger are raising both Ozark hellbenders and eastern hellbenders, which live between southern New York and eastern Missouri.
Tests suggest that Missouri hellbenders have lower sperm counts than their counterparts in North Carolina and Georgia, Mathis said. A similar study on humans from Columbia, Mo., Minneapolis, Los Angeles and New York City showed the Missouri men tested had the lowest sperm count.
It get's worse:
Stanley Trauth, a zoology professor at Arkansas State University in Jonesboro, showed pictures of hellbenders with open sores, tumors and missing limbs and eyes. He said that nine out of 10 animals found in the Spring River — mainly in northern Arkansas — this year had serious abnormalities.
"I'm at a loss, folks," Trauth said. "We just don't have a good explanation for what's causing this."
Max Nickerson of the University of Florida, who has worked with hellbenders for three decades, said his early research did not find nearly as many abnormalities. He called the new results baffling.
Other possible causes of the decline include introduced species of trout which juvenile Ozark Hellbenders do not seem to recognize as predators.
Northern Prairie Wildlife Research Center
St. Louis Zoo