The brown anole (Anolis sagrei) was discovered in Santzepu, Chiayi County, southwestern Taiwan, in mid 2000, and except for a few academics, most people didn’t seem to notice the existence of this exotic invasive species. That all changed when red fire ants (Solenopsis invicta) were discovered in northern parts of the island in 2003. Suddenly, invasive species became a very hot topic, and the authorities launched various projects to assess and study invasive species in Taiwan. Soon, as could be expected, A. sagrei was also in the news.
In spite of the interviews we had with journalists, and the information we shared with them about A. sagrei, they continued to report some of the most ridiculous stories. For example, a journalist contacted me because the chief of a borough of Santzepu claimed to have observed a cat eating several A. sagrei, after which the cat’s mouth pulled skew, so the journalist wanted to know whether the brown anole is poisonous. I assured them during the interview that these lizards are harmless to humans and pets. In the resulting article however, the journalist mentioned my comments in addition to the claims of the borough chief, but also stated that the authorities are not certain. The borough chief’s concern that the brown anole might cause harm to the residents and the environment in the same way as the tropical fire ant (Solenopsis geminata) had done, as well as his request that the authorities do something about it were also mentioned. The irony is, S. geminata has existed in the area for decades, and no one seemed to have noticed until the media mentioned S. invicta.
In another article, the journalist misrepresented the information we shared. In the article it was stated that about 10% of the lizard’s diet in Taiwan is spiders, which is correct. It also claimed that 90% of its diet consists of ants, which is incorrect! Ants make up about 50% of their diet. The article then elaborated about the environmental impact of such a predator on the native wildlife, but it failed to mention, as I pointed out during the interview, that the habitat destruction caused by humans and their activities in the area is much more damaging than the lizards can ever be. I also mentioned that these lizards prey mainly on ants such as the big headed ant (Pheidole megacephala), which is also an exotic invasive species – and which has the ability to negatively affect invertebrates and can displace even fire ants – but this was not mentioned in the articles.
When the authorities mentioned the possibility of exterminating of the brown anole in Taiwan, I told them that if it were possible, it would be a good thing. However, I also stated that I highly doubted if it could be done, and I was very against the idea of using the general public in this exercise. In 2007 the authorities tried to use some university students to remove the brown anoles from the wild in Santzepu. And to my dismay, in 2009 it was announced that the authorities had placed a bounty (N.T.$ 20 = ca. U.S.$ 0.70) on A. sagrei in Chiayi County, and a certain amount of money had been allocated for paying the residents for every lizard they collected. When they ran out of funds the newspaper articles were very depressing – photographs of bottles filled with thousands of dead lizards were printed, and in one article A. sagrei was incorrectly labeled as the endemic Swinhoe’s tree lizard (Japalura swinhonis) and vice versa (see the attached photo). But the carnage did not end there! In 2010, more money was allocated for the extermination of A. sagrei. And the result? Thousands more lizards died (many of which I believe were not A. sagrei), they ran out of funds again, and the brown anole still exists in Santzepu.
This year my colleagues and I intend to map the known distribution of A. sagrei in Taiwan, and I hope that the results would reveal to the authorities that the extent of the brown anole invasion is larger than what they realize, and that the killing of thousands of lizards in some localities will not resolve this situation. My honest opinion is, we have to accept that the brown anole is in Taiwan to stay and is becoming part of the local ecosystems. Since our studies have shown that the secondary forest in our study area has a higher variety of native wildlife than that in the neighboring agricultural areas, and because the brown anole also tends to avoid areas with a denser canopy, I strongly believe the best action to take would be to restore more habitats. This would not only lead to an increase in the population sizes of local wildlife, but could also alleviate some of the environmental problems that Taiwan is facing, and at the same time hinder the spread of the brown anole and other invasive species.