Lately, I have been working on a piece of art on Alligator Gar, Atractosteus spatula,
that lead me to write on this subject. Gar are a fascinating fish, rightfully respected by both anglers and scientists.
From Wiki: "the gar
) is strictly applied to members of the Lepisosteidae
, a family including seven living species of fish in two genera that inhabit fresh, brackish, and occasionally marine, waters of eastern North America
, Central America
, and the Caribbean
The reason I bring up this group of fish is that, yes, it is possible to drown them which surprises a lot of fish-laypersons. Its just such a counter intuitive idea. You can drown any fish in the right conditions, but gar are a bit special. The deal is that gar have a special circulatory system centered around their swim bladder. The swim bladder in fishes is closely related, homologous, to lungs in terrestrial vertebrates. Scientists think that the first lungs, which would have been simple sacs connected to the gut that allowed the organism to gulp air under oxygen-poor conditions, evolved into the lungs of today's terrestrial vertebrates and some fish (e.g. lungfish, gar, and bichir). So gar use this quasi-lung when they gulp air and supplement the oxygen obtained through their gills. Gar are often found in slack turbid water, and seen sticking their toothy mugs out of the water to gulp air to allow gas exchange in their swim bladders. When dissolved oxygen is low enough in water, all fish would effectively drown, but gar would be among the first without this ability because their gills aren't as efficient as most other fishes. These critters are often found in oxygen poor waters, so this ability to breath from air no doubt comes in handy. When using gill nets, these guys are among the first to perish if left in too long.
Here's that Gyotaku art print that I recently put up on inkedanimal.com.
A quick node to the awesomeness of this animal. It's the largest freshwater predator in at least North America.
Ben Labay is a "fish-geek" and research associate for the Texas Natural History Collections at UT Austin
See his fish art at: www.inkedanimal.com