Bloop: A Crustacean Phenomenon?

Dear Blue Lobster:

do you know anything about bloop? i learned that it was a sound that the government recorded and that it's from a living creature, but i don't know any more than that. it happened in the ocean near south america, so i figured since you spend time down there you'd know.

thanks,
brock

Dear Gentle Sir:

Bloop was recorded in 1997 not by the United States Navy but instead by the National Oceanic and Atmospheric Administration, a spying front for the United States military. Originating near 50º S 100º W, some 1,500 kilometres from the Republic of Chile, the sound was recorded by SONAR equipment more than 5,000 kilometres apart. Though researched by both academic and military specialists, no consensus was reached regarding the sound's origin.

A few facts about Bloop were disclosed that continue to intrigue the scientific community. One is that the frequency was outside the range of seismic and volcanic activity. It was, however, within the frequency that biological organisms create. The puzzler there is that the sound was so powerful no living creature, including Blue Whales or the largest known Giant and Colossal Squids, could have produced it.

To produce a sound strong enough to be heard across 5,000 kilometres of ocean at depths averaging four kilometres, the sound would have had to originate at roughly 300dB, loud enough to cause violent hemorrhaging, disorientation, and death in humans. To generate such a powerful sound, the creature would require a body mass of about 200 square meters, larger than even a Blue Whale.

There are few candidates to explain such a creature. The possibility of it being an unknown species of whale is slim, as whales must surface to breathe and an animal one and a half times the size of a Blue Whale would surely have been recorded. Theories about Bloop being a Giant Squid species or the Colossal Squid are without merit, as the largest of either species falls well below the required size and cephalopods also lack organs for generating sound.

One theory that does hold merit is that the creature is a gigantic crustacean. Lobsters and crabs "burp" bubbles of carbon dioxide gas from their gills and often retain the air to belch at other species and to impress potential mates. Comparing the Bloop sound profile to crustacean belches nets the most similarities despite obvious difference in strength.

Should Bloop have been a giant, heretofore unknown crustacean species, it would explain the similarity of the sound to crustacean burping. A crustacean at such depths would need a shell a foot or more thick to protect it from the crushing weight of the ocean, would grow incredibly slowly, and would be part of a breeding population of perhaps just a few dozen individuals.

Oceanographers and acousticians are currently examining new sounds recorded by the USNOAA, including Glop, Blorp, and Poot, that all have similar signatures in hopes of discovering the source of these enigmatic deep-ocean sounds.