Specimen Showcase | Profession Marine Cleaner 🧹

If the words ecology and economy are so close etymologically, it is also that they are both very much embedded in nature. Indeed, organisms are constantly making decisions (consciously or not) on how to maximize their benefits from the environment while limiting their costs in order to survive and reproduce. Species living near each other are also “doing business together”, and as in our societies, some businesses can be more beneficial than others to both parties involved. Today, we will focus on a species that found a great way to maximize its own survival while ensuring other species' satisfactions .

𝘚𝘵𝘦𝘯𝘰𝘱𝘶𝘴 𝘩𝘪𝘴𝘱𝘪𝘥𝘶𝘴 (Olivier, 1811) presents a red and white striped body covered with spines which also led to its common name: the . Their common name is actually misleading as they are actually not real shrimp. In fact, they are shrimp-like decapod crustaceans with a pair of extra long white antennae and an oversized pair of third legs bearing pincers. These body structures not only give them an eye-catching appearance, but they also enhance their survival. They have a large natural range , being mainly distributed in tropical and some subtropical zones throughout the globe, especially all over the Indo-Pacific areas such as Indonesia and Australia and the tropical seas of Caribbean.

Banded coral shrimp are monogamous, meaning that they would remain with the same mate during a breeding season instead of having multiple ones. In this species, however, the males, which are usually of smaller size than the females, couples will remain together for most of their lifetime, lasting sometimes 2 to 3 years, and sometimes starting while individuals are still juvenile - a kind of crustacean high-school love. But females  have the final say on which male  they want to team up with, and males thus need to show their future aptitudes. To do so, they will perform a courtship dance, swinging their bodies and antennae from left to right for an invitation. If the female is receptive, it will molt first and then pair-up about 12-48 hours later on - so the male doesn’t have time to get under her skin! Jokes aside, females are actually more attractive to males within the first 24 hours after molting, increasing the chance of successful matings during this crucial period .

If you look for banded coral shrimp, then your best chances to observe them are within submarine caves and rock crevices where they hide during the daytime. As a nocturnal species, they prefer searching for food and scavenge on algae, detritus and dead fishes when the lights, and numerous diurnal predators, are gone. Scavenging in a vast ocean, however, may be dangerous and rather inefficient but the banded coral shrimp evolved an original and more efficient strategy to get its supply of food: “Cleaning stations”! The shrimp will advertise its business to fishes and other marine organisms by waving its colored banded claws and antennae at the openings of holes and caves to signal that it can provide a cleaning service. They will use their large chelipeds, which are the pair of legs that bear the large claws, and multiple pairs of smaller claws as cleaning tools, removing parasites and dead tissues from the fish body, gills and fins for their own benefits as snacks . A mutualistic relationship is thus developed between the shrimp and other organisms.

But flourishing businesses are often copied and multiple banded coral shrimps may inhabit the same area, thus increasing the competition to attract customers. To defuse potential economic wars, the shrimps will use their antennae to communicate between individuals and settle their terms to secure their business area and become the sole service provider. But when things go south, violence will be involved. Remember the large chelipeds the shrimp used for picking up parasites? Well, those can have a different function to pick a fight as well. If the ‘talks’ do not work, the shrimp will hold its chelipeds to scare off the enemies. This posture makes the shrimp look like a boxer wearing a pair of boxing gloves , telling others they are ready to fight, thus having the title of ‘boxer shrimp’. The banded coral shrimp has low tolerance to other crustaceans, especially from its own species. The risks of engaging in a fight are real though with injuries and losses of claws or legs. Generally, they can regenerate them after molting, but the regrown one will be smaller. A little sacrifice for keeping the business.

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Text: Alan Tsoi