GET TO KNOW YOUR CARIBBEAN MARINE LIFE
by Darelle Snyman
In previous articles we have looked at some of the odd-shapedfish that grace the Caribbean reefs. Many fish known for their unusual body shapes tend to be slow and awkward. For them speed is just not that important; they rely on other mechanisms to reduce their chances of becoming part of the reef nutrient cycle. Some are poisonous, others are masters of camouflage and some can pack a powerful bite. Below are a few more of these creatively designed creatures that make the underwater world such an amazing place to explore.
The Sharpnose Pufferfish
A group of odd-shaped fish full of personality and charm that needs no introduction is the pufferfish. They are probably best known for their ability to turn themselves into virtually inedible, often spiky balls by inflating their elastic stomachs with huge amounts of water. A predator that swallows a puffer before it inflates will soon regret it.
Most pufferfish contain the foul-tasting and often lethal toxin called tetrodotoxin. There is enough of this deadly toxin in one pufferfish to kill 30 adult humans and there is no known antidote. It is produced by bacteria within the puffers, which they obtain from the algae and invertebrates they feed on.
Toxic or not, they are just fascinating creatures. A really endearing puffer found widely across the Caribbean in a variety of habitats is the
Sharpnose Puffer (Canthigaster rostrata). This is such a fun little fish to encounter, hovering with its little fins as it surveys you from a wary
distance. This large-eyed critter is characterized, as the name indicates, by a pointed snout. It comes in a variety of hues. It has beautiful blue markings on its snout and radiating from its eyes. Its tail fin is edged with wide dark borders, making it an easy fish to identify.
You will find Sharpnose Puffers actively foraging for food during the day. They clearly have no diet restrictions, feeding on small crabs, shrimps, sea urchins, sponges and worms. Their palate also extends to the non-animal variety and they are known to feed on algae and seagrass.
This delicate-looking character, like all puffers, has a very strong beak formed by the fusion of the only four teeth it has. This allows it to crush shells and scrape off algae from the rocks. It is from these four teeth that it received its family name, Tetraodontidae.
Do not be deceived by their gentle look, Sharpnose Puffers are very territorial and females maintain small, permanent territories within
larger territories defended by males. A trespassing puffer shows it submission when passing through a neighbor’s territory by becoming
mottled in color and flattening its belly. The aggrieved property owner will respond with aggressive displays, such as tilting the body and presenting the flank. If the intruder dares to ignore these displays the defending puffer will face its enemy head on with its fins spread to make it look bigger.
Apart from dealing with annoying intrusions from their own kind, Sharpnose Puffers also need to keep an eye out for predators such as the Great Barracuda (Sphyraena barracuda) and the invasive Red Lionfish (Pterois volitans).
Sharpnose Puffers are caring mates and the male helps the female lay her eggs by continuously nudging her in encouragement. Once
the eggs are laid and fertilized both partners return to their territories and the eggs are left uncared for. These adorable fish can live up to ten years and older.
The Slender Filefish
A tiny fish and a true master of camouflage that you really have to hunt for is the Slender Filefish (Monacanthus tuckeri). The Slender Filefish has an amazing ability to change color in the blink of an eye as it swims among the coral. This quick change happens in less than four seconds! Dermal flaps, small projections that protrude from the skin, add to its disguise as they soften the distinct edges of the fish.
These delightful animals are recognized by their long snouts, small mouths and large dewlaps or extendable belly flaps. They range in shades of green to reddish-brown to yellow-brown with a white reticulated body pattern. Like their kin, they also bear a slender, front dorsal spine that is retractable. They live solitary or in pairs and frequent gorgonians where they can remain well hidden among the branches, often hanging vertically in the water, a habit that makes them hard to spot. Here they feed on algae and invertebrates and even rest or sleep at night by biting down on the coral polyps, preventing them from being carried away by the currents. This behavior is a common trait among members of the filefish family.
The Black Durgon
Well-known odd-shaped fish that are more robust in stature are members of the triggerfish or Balistidae family. Triggerfish are united by their oval-shaped bodies and presence of a locking dorsal spine. They use this spine to deter predators or to lock themselves into holes, crevices, and other hiding spots. Many are brightly colored with amazing patterns and markings. These awkward swimmers rely on a somewhat disgruntled disposition and a powerful set of jaws to deter would-be predators.