Holes and Pits: Human Waste and Wonder in the Mariannas Trench

Today in Holes and Pits: Trench Life. The Mariannas Trench, declared a National Monument by George Bush in 2009, is at its lowest point 10,916 m, the deepest point under the ocean in the world. Creatures inhabiting this world of near-total darkness with water pressure more than 1,000 times the average atmospheric pressure at sea level are understandably difficult to study and catalog; 19th century researchers probing deep sea trenches for specimen often ended up with nets of fish goo when these fragile organisms exploded at lower pressures.

These days, scientists employ more sophisticated gadgetry to to capture deep sea animal behavior in situ, sending diving bots with cameras into the breech. In 2016, the National Oceanic and Atmospheric Administration (NOAA) live-streamed its most recent exploration of the trench, capturing and disseminating a trove of oceanographic porn: sea pigs truffling in sediment, angler fish gobbling bio-luminescent jellies, octupi color-shifting in a beds of coral, sea sponges performing water backflips. The Mariannas trench is a menagerie of incredible, lovely, weird (and weirdly-hued) organisms thriving in a landscape that seems uninhabitable to us mouth-breathers.

The Marianas trench ecosystem, however otherworldly, is not isolated from the behaviors of land dwelling creatures and may be under threat from human generated waste. NOAA has a page and a video dedicated just to the consumer debris its robots encountered in the deep (see link below). The accumulative amount of trash is small for now–9 pieces in total on this trip. But each piece is a disturbing harbinger of what’s coming. In the feed, a tied plastic bag ambles lazily by, as if on an exclusive solo trash mission, scouting ahead of a pending plastic bag army. A beer can, rusted from age, is trapped between two rocks, looking more eerily permanent and immutable than the translucent crustaceans that amble past it. Such objects sit uncomfortably in this pristine, alien place.

The record of the debris we’ve left in the rift gets worse than a handful of solid trash items, though. In Feb of 2017, a study by Alan Jamieson (et. al) in the journal Nature, Ecology and Evolution reported that persistent organics pollutants (POPs) were found in organisms living at depths up to 10,000 m. Hirondellea giga, a shrimp-like (or, flea like) critter studied by Jamison’s team, showed fatty tissue accumulations of PCBs (a chemical once used in electric equipment and banned in the 1970s) and PBDEs, (a chemical used in industrial processes and landfills). Our shrimp critters most likely came by these chemicals by way of their local food chain; as bigger contaminated animals died and sank to the bottom of the trench, they became food for these flea-like scavengers of the deep, who absorbed their record of contaminants as a part of their meal.

The bioaccumulation of POPs in creatures living in this type of environment is particularly disturbing, not only because we perceive it as remote and unconnected to human activity, but also because it is disastrously one-directional; objects and pollutants that roll their way down to the deepest ecosystem in the earth are unlikely to redistribute themselves. Instead, they only grown in concentration. It’s a frightening call to action when the banality of our consumption habits, from cheap electronics to spam, reaches down into the deepest places.