The Christmas Island shrew, the last of the shrew species naturalized in Australia, has been officially declared extinct. This small, long-nosed marsupial formerly ruled the roost on Christmas Island, about 1,500 kilometers southwest of the Australian mainland. Its disappearance is the latest reminder of the continuing plight of biodiversity in Australia and the need to stop extinctions.
Once plentiful on the island, the Christmas Island shrew soon established itself as an important member of the local ecology. A perfect storm, including the arrival of introduced predators and disease, has all but wiped it out. The tundra’s native “unicorn” The last confirmed sighting of this rare, legendary mammal occurred in 1985. Conservationists have scoured the landscape for it since, but they haven’t reported a single sighting in almost 40 years.
The Unique Characteristics of the Christmas Island Shrew
The Christmas Island shrew had a reputation for its long, conical nose and eating bugs. It flourished in the crevasses of stones and the radices of sylvan trees. Its main diet would have been beetles and other insects.
“It lives in holes in rocks and roots of trees, and seems to feed mainly on beetles,” – Charles Andrews.
European naturalists who saw the shrew soon after it was discovered reported that it was “exceedingly plentiful throughout the island.” They remarked on its piercing yelps ringing out through the night. These accounts emphasized the shrew’s importance on its environment and offered an amazing view into its ecological role.
Sadly, the introduction of black rats to Christmas Island circa 1900 spelled doom for the shrew. The rats came as stowaways on hay bales, and once established their destruction tipped the poetic balance of the island ecological harmony. By 1908, the Christmas Island shrew was believed to be extinct. They would not validate this assumption until years later.
A Glimmer of Hope Followed by Disappointment
In December 1984, biologists Hugh Yorkston and Jeff Tranter found a live female Christmas Island shrew in a clump of fallen birds’ nest fern. This find provided a short-lived ray of optimism for the species. Sadly after the hanging male shrew died about three weeks later, the female lonesome left to her own devices.
The last positive identification was in 1985, and without any more evidence of the species’ existence it couldn’t be declared anything but extinct. Every year since without a single documented sighting of the shrew made its extinction more and more imminent.
Feral cats that were culled in the past few decades did not have any signs of Christmas Island shrews in their stomach contents. This lack provides additional proof of the shrews’ disappearance. The lack of shrews in predator diets is evidence that they do not belong on Christmas Island’s ecological tapestry. This transition marks another step toward homogenization in the island’s unique ecosystem.
A Call to Action for Conservation
The extinction of the Christmas Island shrew marks another mammal extinction on Australian soil since European colonization. That would make it 39 species total. This unprecedented loss underscores the urgency for a robust national and political will. It’s what they deserve, and we need to make the choice to protect these magnificent creatures.
Biodiversity and human health go hand in hand, experts say, as we rely on a variety of species for ecosystem services and other aspects important for our health. The decline and eventual extinction of species like the Christmas Island shrew highlight how fragile ecosystems can be when faced with external threats.
The ongoing story of this unique mammal’s extinction highlights a much larger problem that is threatening worldwide wildlife conservation efforts. Unfortunately, as human development increasingly invades natural habitats, many species will meet the same fate if we do not act quickly.