Isn’t it odd how certain creatures elicit delight while others of similar form generate disgust? To me this distinction in feelings is all too real when I compare my reaction to seeing a spiny lobster to that of a cockroach. Both animals are very similar in form and function – long sensory antennae, body consisting of head, thorax and abdomen, numerous hairy legs; both opportunistic omnivores. But the cockroach has scared me off my favourite oceanic islands and the most majestic tallships, while the lobster on the other hand prods my scientific curiosity. I studied the reproductive ecology of American lobsters for my master’s at the University of Maine, USA and my affinity for these crustaceans has followed me to the tropical islands of the Indian Ocean. Tropical spiny lobsters are bizarre but beautiful, with complex life histories and population dynamics that can take many human life times to uncover.
The common names of spiny lobsters like the painted (Panulirus versicolor), ornate (P. ornatus) or scalloped (P. homarus) demonstrate their visual appeal. Tropical shallow-water spiny lobsters are intricately patterned and display a wider range of colors than an artist’s palette. The carapace that protects the cephalothorax and the base of the antennae and feet are all covered in forward pointed spines, making it tricky to capture them unless you have evolved to prey on them or are a trained lobster biologist or fisher. Their exquisite colours are often lost when the lobster is cooked; the heat turns the exoskeleton into a bright red. Thus the beauty is best observed on dives or at fish landing sites and stores. Lobsters have evolved to be creatures of the night and only step out of their holes and crevices after dusk after their visual predators like triggerfish have gone to bed. During the day, the gregarious adults hang in groups of 2 or more, often hiding in coral crevices and under ledges. The juveniles tend to be more solitary occupying small coral holes. But they all sit with their faces pointed outwards, their antennae gently swaying in the tropical waters that are full of smells, sounds and vibrations. The sway of lobster antennae is very similar to the sway of cockroach antennae both of which I have gotten very good at detecting, albeit for different reasons and outcomes.
In the Andaman Islands, where I am currently based, there are at least 6 species of spicy lobster and 1 species of slipper lobster. With exponentially expanding seafood export industries, understanding the ecology of our island lobsters hasbecome more vital than ever before. Like most benthic marine life – lobsters have a biphasic life cycle: adults remain on the bottom (‘the benthos’), while their larvae travel the seas in search of food and meaning. Pelagic dispersal of benthic marine organisms can be advantageous as it opens up opportunities to find better habitat, increase genetic exchange and avoid benthic predators. Such dispersal can also be beneficial to fisheries by replenishing depleted stocks. Luckily the Andaman Islands have a network of protected areas that include marine parks and tribal reserves but the overlap of protection and species sources and sinks is yet to be determined.