Consumtpion of Egg-Carrying Females Endangers Rare Iguana

It’s a simple equation, really: If a species can’t reproduce, it will go extinct. A critically endangered species in Honduras faces that risk in a notable way.

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It's a simple equation, really: If a species can't reproduce, it will go extinct. A critically endangered species in Honduras faces that risk in a notable way. It turns out that the people who coexist with Valle de Aguán spiny-tailed iguanas (Ctenosaura melanosterna) not only like to eat the lizards they prefer the taste of females that are carrying eggs. A study uncovering this dangerous preference was published last month in Herpetological Conservation & Biology (pdf).

According to lead researcher Stesha Pasachnik, a postdoctoral research associate for the San Diego Zoo Institute for Conservation Research, this overharvesting of egg-carrying iguanas "is not only not sustainable but is likely to accelerate this species's extinction due to the loss of gravid females."

To assess the threats to this and two other local iguana species, Pasachnik and her fellow researchers visited the Rio Aguán Valley and conducted 132 interviews about how the people there consume the lizards. They found that 68 percent of respondents acknowledged eating C.melanosterna, with 26 people saying they ate anywhere from one a year to three a week. The researchers calculated the average annual iguana consumption at more than 15 lizards per person. Although consumption occurs year-round, there is also an annual festival that celebrates eating the iguanas.


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Of those people who acknowledged eating the species, 60 percent said they preferred to eat egg-carrying females, usually by preparing the eggs and meat in a soup with coconut milk. Some people did it for nourishment. Others cited supposed medicinal qualities ranging from cures for cancer and diabetes to increasing appetite or removing scars.

The study did more than just assess this threat to the species. The researchers also asked people how open they would be to efforts to conserve it and found a great deal of support for the idea. They survey found that 80 percent of people in the iguana's range feared that it would go extinct and that 94 percent welcomed international assistance because it could lead to a sustainable harvest that would ensure the iguanas existed for future generations. As the researchers wrote in their paper, "This type of study opens the door to start those conversations with locals such that we may begin to work towards co-management strategies."

Of course conserving the species will take more than just stopping a few dozen people from eating it. The valley has also been heavily deforested for banana plantations, cattle and other agriculture, which has destroyed at least 50 percent of the iguana's habitat. Feral dogs, cats and invasive rats are also prevalent in the region. But even with all of those threats, this study reveals that the people of Aguán Valley place value in their local iguanas; that alone is half the battle for conservation.

Photo by Stesha Pasachnik courtesy of the San Diego Zoo Institute for Conservation Research

Previously in Extinction Countdown:

John R. Platt is the editor of The Revelator. An award-winning environmental journalist, his work has appeared in Scientific American, Audubon, Motherboard, and numerous other magazines and publications. His "Extinction Countdown" column has run continuously since 2004 and has covered news and science related to more than 1,000 endangered species. John lives on the outskirts of Portland, Ore., where he finds himself surrounded by animals and cartoonists.

More by John R. Platt

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