Archive: ‘Salamander Love Doctor’ Strikes Again

Director of Award-Winning National Amphibian Conservation Center Using Hormones to Help Vulnerable Species

August 12, 2020

ROYAL OAK, Mich., 

When you have a salamander species at risk, who are you going to call? Detroit Zoological Society’s Dr. Ruth Marcec-Greaves. Affectionately referred to as the “salamander love doctor,” Marcec-Greaves has helped bolster salamander populations, as well as other amphibian populations, around the world — with the latest success story unfolding with the Edwards Aquifer Refugia Program at the San Marcos Aquatic Resources Center in San Marcos, Texas.

At the refugia, which acts as a reserve for vulnerable species, Marcec-Greaves, who is the director of the Detroit Zoo’s award-winning National Amphibian Conservation Center, is working with the U.S. Fish and Wildlife Service (USFWS) to understand if the use of liquid hormones can improve the predictability of captive breeding success of two salamander species, the endangered Texas blind salamander and the threatened San Marcos salamander.

“We were really excited to see initial success with the salamanders laying more egg clutches,” said Marcec-Greaves.

It is likely that vulnerable populations may someday benefit from supplementation with captive-born salamanders to ensure their survival, and creation of successful captive-reared populations is a critical first step in a reintroduction program. Both species successfully reproduce in the refugia, but at lower rates than would be needed for reintroduction.

Marcec-Greaves helped develop protocols to test whether hormones can influence increased salamander breeding at the refugia earlier this year. She trained USFWS staff to carefully place liquid hormone on the facial receptors of San Marcos salamanders.

“Salamanders have grooves on their faces, which soak up the hormones,” Marcec-Greaves said.

Following the hormone treatments for both sexes, biologists observed increased courtship behavior and female salamanders producing eggs within a few weeks. The staff at the refugia has also recently used this protocol with Texas blind salamanders with promising results.  Normally, Texas blind salamanders in the refugia population produce two to three egg clutches per year with an average of 20 eggs per clutch. This important pilot project has resulted in nine egg clutches in three months.

“While these first steps appear to be working, more work is needed to fully understand salamander reproductive physiology and this assisted reproduction strategy specifically,” Marcec-Greaves said.

“Forging this new partnership between the Refugia Program and the National Amphibian Conservation Center is exciting and beneficial for all involved, especially the salamander species.  Adding Dr. Marcec-Greaves expertise and experience in amphibian reproductive physiology to our specific knowledge of our salamanders is advancing our intelligence around the complexity of on demand reproduction for these endemic species,” said Dr. Lindsay Glass Campbell, Managing Biologist of the Refugia Program, USFWS.

Marcec-Greaves has been the director of the NACC since January of 2017. When the National Amphibian Conservation Center opened at the Detroit Zoo in 2000, it was the first major facility dedicated entirely to conserving and exhibiting amphibians, and it remains the largest. The award-winning, state-of-the-art amphibian center is home to a spectacular diversity of frogs, toads, salamanders, newts and caecilians, many of which are threatened, endangered, and represent vital field conservation efforts.