Tarpon Profile

Fish keep a lot of secrets behind their seemingly painted-on faces. It was once thought they were incapable of feeling pain at all, and, much in the way medical wisdom in the ‘50s considered human babies unworthy of anaesthesia, fish are still subjected to tremendous abuse in the wake of human ignorance.  

And today’s animal is just such an example: stuck with a name that’s a mere kerning error away from an absorbent insertable: the tarpon.

Tarpon Facts Overview

The tarpon is either of two species of fish from coastal waters all over the tropics and temperate regions of the Atlantic and Pacific. These two species are alone in their family, not too far removed from the eels, only far brighter, fishier, and very, very silver. These silver kings can breathe air, talk, hide in brackish, low-oxygen waters, and produce a dazzling number of offspring. Sadly, they suffer many losses from catch-and-release fishing and the destruction of their breeding sanctuaries.  

Interesting Tarpon Facts

1. Silver Kings and ladyfish

It really goes to show the lack of respect this fish receives that its other common name sounds like it came out of a Joe Satriani album, and everyone still goes with tarpon. The Silver King is a far more worthy name for these species, as they are very silvery and very large, at up to almost 130kg in some exceptional individuals.

Silver kings are members of the Elopiformes order, named after the Elops genus of so-called ladyfish, with which they share the order. This order is very nearly an eel, though they don’t really look it. True eels are in the Anguilliformes order, which is closely related to the Elopiformes, and both share a superorder called Elopomorpha.

Tarpons are the only two species in their entire family, the Megalopidae.

Eels are known for being able to store atmospheric air around their gills, slow their heart rate, and basically survive for a little while out of the water as a result. Silver kings can’t do this, exactly, but they can take large gulps of air when swimming in low-oxygen waters.

2. They gulp air

Tarpons have highly vascularised swim bladders, which allow them to absorb oxygen from air by coming to the surface to take a gulp.

This form of aerial respiration isn’t as efficient as ours, nor as the gills of the fish when working in oxygen-rich water, but it is a very important supplement to their oxygen intake when swimming into waters that are low in oxygen. Their swim bladder itself is modified to have alveolar tissue, with lots of surface area for breaking up the air and connecting it with the blood vessels around the bladder.

And so, this ability allows them to encroach into waters where their predators can’t, and so helps keep them safe.

So, they already have exceptional bladders! But there’s even more that the tarpon can do with their special organ. ¹

3. They thump

The Atlantic tarpon (and probably the other one, too – though there’s less data on the Indo-Pacific species) can make thumping noises with its swim bladder to communicate with its friends and rivals.

This is a fairly new discovery in fish as a whole, and the social consciousness remains lagging behind when it comes to fish, but it is rapidly becoming clear that they have far more complex, richer, and intricate social lives than their dumb, expressionless faces (read: our dumb, mammalian biases) would have us believe.

And tarpons are one such species schooling us in this.

Vibrations are passed through the bladder, which can be used to chat or to try and intimidate predators. ²

4. They can breed all year ‘round

Megalops species appear to be able to breed at any time of the year, though each spawning session will usually only occur once annually.

Spawning is pretty impressive, too, with up to 20 million eggs released. This is the epitome of an r-strategy to breeding – one that involves a tremendous quantity of low-maintenance offspring, as opposed to the K-strategy of one or two really expensive ones.

But unlike the stereotypical r-strategist, tarpons live remarkably long lives of many decades, and can mature fairly slowly, too. While eggs hatch in just 2 to 3 days, sexual maturity can take 6 to 13 or more days.

And so, this slow maturation makes for a slow recovery when the species suffers catastrophic losses.

5. They’re sensitive to temperature changes

Despite being pretty tough in regards to the salinity and oxygen gradients they can tolerate, tarpons are susceptible to temperature changes, and prefer a comfortable room temperature of around 26 degrees Celsius.

If their habitat drops below 10 degrees, they will die, and sudden changes can also be lethal to large swathes of their population. These changes can and do occur naturally, and the species likely has a population buffer against them as a result, but other threats are more serious.

6. They’re in danger

Fishing is a morbid juxtaposition between the social bonding, sport, and/or meditative practice elements of the human side of the experience, and the painful, horrifying and mostly lethal brutality of the fish’s side.

And it’s still a little-known fact that fish not only feel pain and fear, they often die from the experience of being caught – even if they’re thrown back. Catch and release fishing, for the fish, at least, is by no means a fun sport, and many species, including the tarpon, have a fairly low chance of surviving the ordeal.

And Atlantic tarpon are struggling as a result. Being a large and beautiful fish, they’re popular among fishers, they’re caught a lot, and when released, can be snapped up by predators while they’re still trying to get their energy back. Larger individuals put up more of a fight and are worn out more significantly, while juveniles are generally less affected, but the long-term survival rates after release are not known.

The data on the Indo-Pacific species is not complete enough for an assessment, but the Atlantic tarpon is considered Vulnerable and in decline. ³

7. They need coastal habitats

Larval stages of both species rely on habitats that we commonly take for granted. Mangroves, estuaries, and even canals can provide the necessary nursery habitats for tarpons to breed, and all of these are at risk of pollution and destruction.

Declining water quality and habitat destruction are the two other major threats to both species. ⁴

Tarpon Fact-File Summary

Scientific Classification

1. Jennifer Burnham (2005), “Megalops atlanticus ”, Animal Diversity Web .
2. (2018) “Atlantic Tarpon”, IUCN Red List.
3. (2018), “Atlantic Tarpon”,IUCN Red List.
4. (2016), “Indo-Pacific Tarpon”, IUCN Red List.