Halfbeaks are among the most commonly seen fishes in the mangroves. Tidal creeks and larger rivers often swarm with untidy schools of these surface dwellers, which tend to gather around anchorages such as bridges and trees, perhaps to elude open water predators or because that is where the feeding is best. A few, smaller species, such as this strikingly marked resident of Pulau Subar Darat, can also be found on intertidal reef flats, typically in the company of nervous silversides, where they haunt the topmost reaches of the water column and snap up floating particles of vegetation or zooplankton.
Having stiff, slender bodies with largely plain colours, hemiramphids would probably draw little attention from lay ichthyophiles were it not for their bizarre mouthparts. The upper mandible tapers as one might expect in a fish of such slim proportions, but the lower half protrudes to unreasonable lengths. Those who have taken a closer look, however, have discovered that the elongated portion is not a jaw sensu stricto but a chin of unusual length. A sensory function has been posited for the organ, but another, albeit untested, hypothesis that comes to mind concerns the adaptive benefits of being just a little harder to swallow than one's build might suggest. Whatever the answer may be, the halfbeaks have cornered a happy niche for themselves in lakes, rivers, mangroves and inshore seas worldwide, where they ride the bellyside of swells and skim off the first fruits of life that fall or form on this cream of sunlight and seasonal liquidity.
The seagrasses and seaweeds that bloom and bust on local shores also harbour other fish of similar shape and size to the halfbeaks but lacking the unequal bite and displaying a marked preference for the midwater. Usually greenish with a row of light markings on the flanks, these fish are thought to be post-larval sphyraenids bidding their time before they grow into bigger game. Adult barracuda, far too large to be satisfied with the fry of shallow flats, have been spotted in healthier reefs and landed at various angling hotspots around the island, suggesting that a sporting population of these toothy hunters still survives despite a regular gauntlet of hooks and the far harder challenge of making a living in a shrinking sea.
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