Atlantic sea turtle population threatened by egg infection

Oct 29, 2010

An international team of Mycologists and Ecologists studying Atlantic sea turtles at Cape Verde have discovered that the species is under threat from a fungal infection which targets eggs. The research, published in FEMS Microbiology Letters , reveals how the fungus Fusarium solani may have played a key role in the 30-year decline in turtle numbers.

"In the past 30 years we have witnessed an abrupt decline in the number of nesting beaches of sea worldwide," said Drs. Javier Diéguez-Uribeondo and Adolfo Marco from Consejo Superior de Investigaciones Cientificas- CSIC Spain. "While many of the reasons for this are related to the human impact of the costal environment it has been suspected that the decline is also due to pathogenic microorganisms."

Fusarium solani is a complex fungal strain which represents over 45 phylogenetic and biological species. The is distributed through soil and can cause serious plant diseases. The fungus is known to have infected at least 111 plant species spanning 87 genera and has also been shown to cause disease in other animals with immunodeficiency.

During embryonic development turtle spend long periods covered by sand under conditions of high humidity and warm temperatures, which are known to favor the growth of soil-born fungi.

Dr Diéguez-Uribeondo's team focused their study on the loggerhead sea turtle (Caretta caretta) population on Boavista Island, Cape Verde, off the West African coast. While Boavista Island represents one of the most important nesting regions for this species a high hatching failure rate is driving population numbers down.

The team sampled egg shells with early and severe symptoms of infection, as well as diseased embryos from sea turtle nests located in Ervatao, Joao Barrosa and Curral Velho beaches and discovered 25 isolates of F. solani associated with egg mass mortalities.

Although this fungal species has been previously described in association with different infections in animals, its relationship to hatching failure had not been investigated before this study.

The finding that strains of F. solani may act as a primary pathogen in loggerhead represents an extremely high risk to the conservation of loggerhead sea turtles across the area.

However, the description of these particular fungal strains causing this infection may help in developing conservation programs based on artificial incubation and may aid the development of preventative methods in the field to reduce or totally erase the presence of F. solani in turtle nests.

"This work reveals that a strain of F. solani is responsible for the symptoms observed on turtle nesting beaches," concluded Dr Diéguez-Uribeondo. "This shows that the infection represents a serious risk for the survival of this endangered species, while also showing immunologists and conservationists where to focus their research."

Explore further: Call for alternative identification methods for endangered species

add to favorites email to friend print save as pdf

Related Stories

Loggerhead turtles on decline in Florida

Apr 20, 2008

The number of loggerhead sea turtle nests is on the decline throughout Florida, indicating a potential threat to the animals, wildlife experts say.

Capture of Female Loggerhead Turtle Recorded from Space

Aug 27, 2004

Scientists leading an international effort to safeguard the future of endangered loggerhead turtles have this week watched the capture and demise of one of their turtles being tracked by satellite. This week ...

Recommended for you

Scientists tether lionfish to Cayman reefs

6 hours ago

Research done by U.S. scientists in the Cayman Islands suggests that native predators can be trained to gobble up invasive lionfish that colonize regional reefs and voraciously prey on juvenile marine creatures.

India's ancient mammals survived multiple pressures

Apr 17, 2014

Most of the mammals that lived in India 200,000 years ago still roam the subcontinent today, in spite of two ice ages, a volcanic super-eruption and the arrival of people, a study reveals.

User comments : 0

More news stories

Researchers develop new model of cellular movement

(Phys.org) —Cell movement plays an important role in a host of biological functions from embryonic development to repairing wounded tissue. It also enables cancer cells to break free from their sites of ...

Scientists tether lionfish to Cayman reefs

Research done by U.S. scientists in the Cayman Islands suggests that native predators can be trained to gobble up invasive lionfish that colonize regional reefs and voraciously prey on juvenile marine creatures.