Study shows that cancer is unlikely to cause extinction in Tasmanian devils

A study found that a cancer that devastated Tasmanian devil populations is unlikely to cause extinction of the species.

Research by the University of Swansea suggests that it is more likely that the disease will subside or that devils will coexist with Tasmanian Devil's Facial Tumor Disease (DFTD).

The majority of the devils infected by the disease are killed by it, with 80% of the demons in nature eliminated and a continuing decline in extant populations since the first identification of DFTD.

An international team of scientists from the United Kingdom, Australia and the United States compared field-collected epidemiological data from wild populations collected over a 10-year period with simulation studies.

This revealed that it is unlikely that the DFTD will cause the continuing decline of the Tasmanian devil population in the future.

The team says their work, published in the journal Ecology, suggests that the species will not necessarily disappear because of the DFTD.

Dr. Konstans Wells, University of Swansea, said, "Our results suggest that it is unlikely that immediate management interventions are required to ensure the survival of Tasmanian devil populations.

"This is explained by the fact that the marked decline in the population of demons after the emergence of the disease does not necessarily translate into a long-term decline in the population."

The disease, discovered for the first time in 1996 in northeastern Tasmania, Australia, causes the formation of tumors on the face and neck of the animal.

It spreads when devils bite their face during fights and kill them within six to 24 months.

The researchers simulated a possible spread of the disease in demons.

The most likely scenarios included the progressive disappearance of the disease or the coexistence of devils.

Dr. Rodrigo Hamede, from the University of Tasmania, said: "With evidence increasingly evident that demons are showing signs of adaptation to the DFTD and that, until now, the disease has not caused local extinctions, management actions to understand the devil's coping strategies to deal with the DFTD should be considered.

"The complete eradication of the DFTD is not achievable. Therefore, studying the long-term interactions between devils and tumors will provide a realistic prognosis for the species while helping us understand important evolutionary processes.

"This is particularly relevant given the recent outbreak of a new cancer – the devil's facial tumor 2 – affecting devil populations in southeastern Tasmania.

"Demons seem to be predisposed to transmissible cancers, so it is a priority to study the dynamics of epidemics and the evolutionary responses to this type of disease."