Quantcast

Sierra Magazine: Explore, enjoy and protect the planet.
Printer-friendly version Share:  Share this page on FacebookShare this page on TwitterShare this page by emailShare this page with other services

GRAPPLE | WITH ISSUES AND IDEAS

Don't Sweat It, Mr. President! | Graphic: Small and Getting Smaller | Critter: Bat-Eating Spider |
Ten Legged Sea Cannibals |The Next Big Thing: Pee? | On the One Hand: Pets | Up to Speed

CRITTER: BAT-EATING SPIDER
When echolocation fails

Bat-eating spider
Photo by Yasunori Maezono, Kyoto University, Japan

Here's inspiration for a Halloween nightmare: an adult proboscis bat caught in the web of the orb-weaving spider Argiope savignyi at La Selva Biological Station in Costa Rica. Chiropterophagy—i.e., bat eating--turns out to be more common than anyone suspected, according to a recent paper in the journal PLOS ONE. In it, Martin Nyffeler and Mirjam Knoernschild cite "numerous ... instances where spiders were seen actively attacking, killing, and eating the captured bats."

A variety of species opportunistically prey on bats that get tangled in their webs, but large tropical orb weavers of the genus Nephila, whose strong webs can span five feet, seem to be the most voracious bat-chompers. While echolocation enables bats to avoid most webs, Nephila sometimes spin webs in large aggregations, which can (and do) snare unfortunate bats. One theory holds that these spiders require "the occasional catch of large, energetically rewarding prey" to reproduce. Since a bat would yield 10 times the biomass of a spider's daily diet, chiropterophagy should guarantee a nightmarish new generation. —Paul Rauber

NEXT: The Next Big Thing: Pee?



Sierra Club® and "Explore, enjoy and protect the planet"® are registered trademarks of the Sierra Club. © 2014 Sierra Club.
The Sierra Club Seal is a registered copyright, service mark, and trademark of the Sierra Club.