It’s tough to stand out in the world of mice. The long-nosed Luzon forest mouse did it by living inside an active volcano in the Philippines – earning it the name Pinatubo volcano mouse. Unfortunately, Mount Pinatubo on the island of Luzon erupted violently on June 15, 1991, killing over 800 people, the lush forests that covered its slopes … and the last of the Pinatubo volcano mice. Or so it was thought. After not having been seen in decades, a recent survey of the volcano – which still shows evidence of the devastation – found the Pinatubo volcano mice somehow survived and are making a comeback.
“When Pinatubo blew up, probably the last thing on anyone’s mind was that a little species of mouse was thought to live only on that one mountain, and might well have become extinct as a result.”
In a University of Utah press release, Larry Heaney, the Negaunee Curator of Mammals at Chicago’s Field Museum and a co-author of a new paper on the discovery in the Philippine Journal of Science, told fellow author Eric Rickart, curator of zoology at the Natural History Museum of Utah, about why nothing was expected to have survived the 1991 Pinatubo eruption. Considered to be the second-most powerful volcanic eruption of the 20th century, ten times stronger than Mount Saint Helens, it erupted more than 5 cu km (1.2 cu mi) of material and sent an ash cloud 35 km (22 mi) into the atmosphere during a typhoon, which carried the ash around the globe. Lava flows and typhoon floods filled valleys up to 200 m (660 ft) deep, and the summit collapsed to form a 2.5 km (1.6 mi) wide caldera. As a famous poem goes, “Not a creature was stirring, not even a mouse.”
“After the eruption of Pinatubo, we looked for this mouse on other peaks in the Zambales Mountains but failed to find it, suggesting a very limited geographic distribution for the species. We thought the volcano might be the only place this mouse lived.”
Only mentioned in a 1962 survey and listed as a new species, Heaney says the Pinatubo volcano mouse (Apomys sacobianus) was not expected to have survived. Twenty years after the eruption, the mountain was still eroding and hardly any vegetation was growing – nothing like the lush forests before the eruption. And yet, a survey in 2011 by Field Museum researcher Danilo (Danny) Balete found some native rodents had survived. Unfortunately, he passed away in 2017 before he could determine if the Pinatubo volcano mouse was one of them. In honor of their friend, Rickart and Heaney went back recently and looked again. They found rodents thriving, and …
“Most surprising of all, the most abundant species, overwhelmingly, was the volcano mouse Apomys sacobianus. Far from being wiped out by the eruption, this species was thriving in this greatly disturbed landscape along with other native species that also have a high tolerance for disturbance.”
The paper is a tribute to Danny Balete by his friends, although the real winner is the Pinatubo volcano mouse.
If a mouse can survive the second-most powerful volcanic eruption of the 20th century, we humans should be able to survive our current problems … shouldn’t we?