DATE: April 8, 2019
SNIP: Last year a terrible accident in India made headlines around the world. Late one February night, a speeding train struck a herd of elephants crossing the tracks, instantly killing two adults and two calves. A third adult died soon after.
It wasn’t an isolated incident. Over the past 30 years train collisions have killed more than 220 elephants in India alone.
Most of those incidents don’t generate international headlines; nor do the deaths of thousands of additional animals killed by trains worldwide each year. In fact most wildlife-train collisions go unnoticed, their fatalities left uncounted — which has made it difficult for experts to study the problem and mitigate its impacts.
Like roads, railways fragment habitat and can affect all kinds of wildlife in varying ways. Collisions are the most common cause of mortality, but some animals die from electrocution or being stuck between the rails, leaving them susceptible to predation, starvation or dehydration.
“The mammal species receiving the most attention are frequently the larger ones, such as moose, bears or elephants as they cause more damage to trains, disrupt the normal operation of the train network, or hold higher conservation and economic status,” according to the editors of the 2017 book Railway Ecology.
Rail tracks can make for tough times if you’re a toad — even a big one.
In Brazil a 2018 study found an estimated 10,000 Cururu toads (Rhinella marina) and related species, often called giant toads, were dying every year along a 500-mile stretch of railway. Researcher Rubem Dornas says they still don’t know exactly why so many toads die, but it appears the tracks formed a barrier the toads can’t cross while migrating. Despite the large size of the toads, which average about 4 to 6 inches in length, the researchers found they may not be able to jump or climb over rails more than 6 inches high.
“We think the main problem is the barrier effect caused by the rails,” said Dornas.
Not all the fatalities are the result of being run over by passing trains. Some of the toads appeared to have died from desiccation due to extreme heat from the tracks.
Most horrifyingly, others showed signs of barotrauma, where a sudden change in air pressure from the fast-moving train causes the inner organs to be blown out — the toads literally exploded from the inside.