Intoduced by people to the Pacific island of Guam in the 1940's, brown tree snakes have decimated bird populations and tampered with the natural top-down trophic control in the island's ecosystem. Because of the elimination of birds as an apex predator, the density of spider webs, and therefore presence of spiders, is 40 times higher on Guam than neighboring islands during the wet season. The large-scale natural experiment, led by Haldre Rogers (UW PhD recipient, 2011), Janneke Hille Ris Lambers, Josh Tewksbury, and Ross Miller (collaborator at the Univ. of Guam), suggests that the impact of bird loss on spider density has been "significantly underestimate[d]" in the past. Results were published in the journal PLoS One.