Secrets of the Ocean Realm
This is a five-part series currently showing in public broadcasting stations around the USA. Take a look at the associated web site "Secrets of the Ocean Realm", and especially the first episode "Cathedral in the Sea", which features the life of Hemisquilla ensigera as it preys on mussels and battles an octopus. I did a brief personal review of the second episode of the series, Venom/Creatures of Darkness.
The pivotal part of the first episode starts when a featureless, sandy plain is suddenly marred by the emergence of two stalked eyes from the sandy ground, which is followed by the relatively "blocky" body of a 25 cm (10 inch) long colorful Hemisquilla mantis shrimp. The stomatopod scurries over to a rocky outcrop, where groups of mussels have welded themselves tightly against the stony substrate. This is no problem for the mantis shrimp, which easily pries loose one of the mussels and retreats back to its den, where it breaks open the shell of the unlucky mussel with several hits from its raptorial appendages.
It is interrupted by the coming of a very large octopus, which moves gracefully over the ground using its sinuous arms. The octopus is nearly 10x larger than the mantis shrimp (almost a meter I'd guess from tip of mantle to tip of an arm), but the stomatopod immediately threatens it by assuming the meral spread position, with its raptorial appendages held wide apart and its cephalothorax thrust upwards and forwards. When the octopus continues to move closer to the burrow, the mantis shrimp suddenly launches itself forward and strikes the cephalopod intruder close to the eye position.
The octopus tries to get away and scuttles all over the place, but the mantis shrimp, which has emerged completely from its burrow to stand warily to one side, hits it twice more before the octopus expels a ton of ink and "jets" out of the area. The mantis shrimp pursues it briefly, then gives out a last threat display before retiring into its den once more.
For octo lovers, there's actually quite a bit of time spent on these creatures. In one scene, a small octopus inadvertantly stumbles on the territory of a much larger fish, which nips at it until the octopus goes away. In another, another octopus wandering around in search of food manages to avoid becoming the meal of a huge scorpionfish (the octopus was a bit too large to fit into the fish's mouth). The octopus, its appetite probably considerably lessened after the near-death experience, goes back to its den, cleans it out some, then notices the approach of a slightly smaller ghost shrimp. The octopus, incredibly enough, "reels in" the crustacean using a a single arm, then munches on the armored prey.
The amount of information in each episode of this series, and the excellent photography, constantly amazes me. A very good series on marine life, and one well worth waiting for and watching.
Web Site Author: A. San Juan
Site Created February 3, 1998