Random encounters with the unusual: Alcatraz’s Weird Residents

The former prison on Alcatraz Island is well known for some of its famous residents, which included Al Capone, Robert “Birdman” Stroud and George “Machine Gun” Kelly (amongst others). The prison closed in 1963 and by the end of that decade the island had become home to a number of Native American activists who stayed for around two years. The island is also reported to be home to a number of ghosts of the former prison inmates.

The weirdest Alcatraz Island resident by far however, is far smaller and more inconspicuous than any of these.

Back in 2012 the island was suffering from a rat infestation, and in a bid to control this problem a dye that fluoresces under ultraviolet light was put into bait. The plan being that the rat’s droppings could then be tracked using UV lights and the rats could be found and eliminated. However, the pest controllers found more than just glowing rat droppings, they found glowing millipedes. It seems that by accident the pest controllers had found an unusual trait of the island’s known species of millipedes, that when illuminated by UV light, that they fluoresce. It is not entirely clear why a mostly nocturnal and blind animal would evolve to emit light, but one theory is that it could be a mechanism to warn predators not to eat them (as they are toxic).