The vigilant predator settles gently on the sandy bottom of the sea while its eyes dilate and probe the darkness for its secrets. This little creature, the Hawaiian Bobtail Squid, also known as Euprymna scolopes, is delicate, sensitive, and endemic to our islands. Although we don’t know all of its secrets, the small Bobtail Squid provides huge possibilities for scientists. Such a creature could be used to solve problems plaguing our world today, and it lives right in our own backyard. One of the squid’s more prominent characteristics is the fact that it "glows" in the dark, which is quite handy considering that it is nocturnal.
The Bobtail Squid is able to use bioluminescent bacteria (Vibrio fischeri) to help it glow, thereby making it possible for the squid to erase its own shadow. Using a cavity on its underside, the squid sweeps in Vibrio fischeri from the ocean with the help of cilia, or small hair-like structures. The Bobtail Squid is able to cultivate these bacteria, which after reaching a certain concentration, begin to glow in the squid’s light organ. The squid can control the light intensity of its bio-flashlight simply by controlling the amount of oxygen that the bacteria in the light organ receive. This light organ is located near the ink sack of the squid, and the muscles in charge of controlling the amount of ink that the squid releases are also in charge of controlling the amount of light that the squid emits. In other words, the Bobtail Squid has a built-in, living flashlight on the underside of its belly. In this way, the Bobtail Squid simply blends into the starry canopy of night sky above, monitoring its light output to match the moonlight above so that it is practically invisible to any predator that may be on the hunt. It also is invisible to its own prey.
Scientists from around the world are interested in this little creature’s symbiotic relationship with the bioluminescent bacteria Vibrio fischeri, and every year, researchers are sent to collect batches of Bobtail Squid from our very own waters. This is no surprise however, because the squid’s ability to cultivate and sustain such bacteria could be helpful in cancer research—bioluminescent bacteria like Vibrio fischeri could be used to mark cancer cells. By understanding the symbiotic relationship between the Bobtail Squid and its bacteria, we may also be able to understand more about our own relationships with the good bacteria in our bodies as well. So, really, protecting the Bobtail Squid is not just protecting another sea creature, but it is preserving and protecting future opportunities for ourselves.