Wood ticks are known to spread diseases including Lyme disease, but they’re also responsible for the decline of a vast amount of the world’s wildlife, according to a new study.
The research, published in PLOS ONE, shows that wood ticks can be the main drivers of the global decline of wild populations of more than 100 species.
The study looked at data collected in more than a dozen countries, including the United States, Russia, China, Brazil, the United Kingdom, Japan and Australia, and showed that the decline in populations of forest wood ticks and of woody plants like beech and beech trees, which can cause the disease, are linked.
“If we don’t do anything to reduce their numbers and they continue to spread disease, then the global population of wood tick will be reduced by as much as 40 percent,” said lead researcher Dr Mark Molloy from the University of Tasmania.
“That’s a huge number, and it’s likely to be even larger in Australia, where woody species are the dominant tree species.”
The researchers also found that the prevalence of wood ticks is lower in countries where wood can be grown, so that the spread of wood-borne diseases can happen in places where trees are not available.
“The tree is the thing that makes it possible for the wood ticks to survive,” said co-author Professor Brian Leech, a professor at the University, “so the tree’s inextricably linked to the population of the wood tick.”
In the United Arab Emirates, the number of forest tick species was down by more than 60 percent since the beginning of the year, while in the US, it fell by a similar amount.
Wood ticks are often considered pests, because they can feed on many different kinds of insects, including beetles, termites, mites, ants and ticks.
But the researchers say that the ticks are also a major source of food for many species of animals.
“I think the species are doing quite well, especially the beetles, which are in the range of the range where they can be a pest in terms of the beetles,” said Dr Mollory.
“They’ve had a good impact on the ecosystems they’re in, but also other species that feed on them.”
The team says the decline has already been confirmed in several European countries, such as the UK, France, Italy and Germany.
“In Germany, the prevalence has gone down by over 60 percent, and in France it’s down by almost 30 percent, in Italy it’s going down by about 50 percent,” Dr Molls said.
“And in Brazil, there’s been a 40 percent decrease, so the numbers have actually gone up by about 80 percent.”
So the species in the tropics are suffering the most.
“Wood ticks, which live in burrows underground, have been found in more locations than they once did.”
Most of the species we found have gone extinct, and there are about 70 species of wood tree that we don.t know how many species there are in Australia,” Dr Leech said.
However, it is not clear whether the woody tick populations are actually declining.”
Wood ticks in Australia and New Zealand are declining, and we know from other studies that the species there aren’t going extinct, so we don,” he said.
This study is one of the first to look at the link between the ticks and the decline, and the authors hope that other studies can provide further clues about how wood tick populations might be changing.”
There are other things that might be happening in Australia that we haven’t been able to detect yet,” Dr Meghan Cope said.