Bowfin anybody?

  • We are currently upgrading MFK. thanks! -neo
From the NANFA site:

Bowfin Basics
By R.W. Wolff
reprinted from American Currents, Fall 1996

If you're in the market for one of North America's magnificent oddballs, it's hard to beat the bowfin, Amia calva. Deriving from an ancient lineage, the bowfin shares traits with both primitive and advanced fish. Although they care for both eggs and fry, these fascinating creatures have never been bred in a home aquarium--offering some pioneering aquarist the chance to be the first to spawn them.

Found in much of the eastern half of the United States, the bowfin prefers slow creeks and the tannin-dark waters of acid-cedar swamps. Ancestors of the bowfin date as far back as the Jurassic period. The genus Amia was once found on most continents and some members of the family were even found in salt water. Today, however, Amia calva is the sole survivor of this once widespread clan.

The bowfin is a "transitional" fish--similar to its relatives the gars, but also sharing traits with the more advanced bony fishes. Like the gars, the bowfin has a largely cartilaginous skeleton. But like the more highly evolved bony fishes, the bowfin has vertebrae that are amphicoelous, or concave at each end. Along with the gars, the bichirs are the bowfin's other living relatives.

The bowfin is a long-bodied fish, about the same height from head to tail. The dorsal fin extends across much of the body; the caudal fin is rounded. The bowfin has a highly developed swimbladder that allows it to gulp air at the water's surface--a definite advantage under low oxygen conditions. Like sharks, bowfins have retractable teeth that remain hidden when the mouth is closed but are exposed when the fish is biting down. The fish's skull also flattens out, to allow them to swallow flat-bodied fish, like sunfish. Favorite foods include crayfish, shad, golden shiners, perch, suckers, and other narrow bodied fish.

Among fishermen, the bowfin is the Rodney Dangerfield of American fishes, never accorded any respect. Many anglers regard it as a "trash fish" that competes with game fish for food. Hooked bowfin are often thrown on the bank to die. In fact, this lack of respect is patently unfair. Hooked bowfin fight as hard as--maybe even better than--any game fish. And adult bowfin can reach trophy size--almost a yard in length and weighing more than 30 pounds.

Such behemoths are, of course, too large for the home aquarium. But the young can be collected almost any time of year, either in the weed beds, in warmer weather, or at creek mouths or openings in the ice in winter. I prefer to start with one-and-a-half to two inch fish. Bowfins I've kept seem to prefer soft water with a pH of 6.8, a temperature of 75 degrees and full spectrum lighting of medium intensity. It's best to set them up in a half-filled 20 gallon long aquarium, with a thick carpet of low plants and an upper covering of floating plants. The dense plant growth provides the skittish young bowfins a sense of security, assuring that they will have less fear of you as they acclimate to their new surroundings. For filtration, I prefer a filter that creates a strong surface current, but with a medium overall tank current.

For the initial feedings, chopped earth worms and shrimp will soon be eagerly accepted. In about a week, they will have acclimated to tank life. As you approach the aquarium, they will swim to the surface in anticipation of their next feeding. About this time, you can introduce them to prepared foods. At first, I offer them some freeze dried tubifex worms, breaking the cube into one-eighth inch pieces. In another three days, I usually start giving them sinking shrimp pellets. The young bowfins will cruise the bottom, inhale the pellets and then hide among the weeds while chewing the pellets up.

Throughout the next month, you can introduce more different types of prepared foods as the fish become more and more accustomed to tank life. If they fail to eat enough of the new food, you can fall back on the chopped worms and shrimp. After the fish accept more types of food and gain more confidence, you can add more water to the tank. About this time, the young bowfins will come to the surface when you splash your finger in the water. At this time, you can introduce them to ground beef, beef heart, and beef liver. Such a highly varied diet will improve the color and growth patterns of the young fish.

Feed the fish twice a day for the first six months. After this time, they should be about 4 to 6 inches in length. Now, you can move them to larger quarters, to a tank containing from 40 to 55 gallons of water. More shallow, wider, tanks are best. I've found that at this stage, spotted gar make excellent tank mates. Bowfins are highly social, and you will see them holding in dense weeds, stacked together like cord wood. Within about a year, the bowfins will reach their maximum captive size of 12 to 16 inches.

In the winter, you may need to subject fish from Northern areas to an extended period of cold temperature (below 50 degrees). Fish not wintered over in this way will eat less and be less active.

Be careful when feeding larger fish, though. They have sharp teeth and very powerful jaws (as any fisherman who has unhooked one can tell you.)

At about this time, also, you will be able to tell the males and females apart. The males have an ocellus on the tail and green pectoral, ventral, and anal fins. The females will have either a black spot or no noticeable spots in the upper tail. Their pectoral, ventral, and anal fins will be grey to brown. In most cases, the males grow faster than the females in the first year. Some fish will develop a blood-red lower third of the caudal fin. On fish with dark markings, this is normal. Moreover, some males will develop extra ocelluses. I've seen up to three (this is very rare).

I'm not aware of anyone having spawned the bowfin in the home aquarium. With the technique I've described here, and with a high-quality diet, the time is right for captive bred bowfins. In the wild, breeding takes place when water temperatures reach about 72 degrees. Typically, the male will seek out an area near an old log or large rock, to provide cover for one side of the nest. Next, he will chew the tops off any reeds in the area before fanning out a depression about 2 feet wide and 5 inches deep. He will also vigorously defend his nest against any rival males.

At night, the male will attract one female at a time into the nest to spawn, with the female laying many green, adhesive eggs in the nest. The eggs, each about 3/16ths of an inch in diameter, adhere to the roots at the bottom of the nest. Males may subsequently spawn with up to three other females. Eventually, the nest may contain up to 5,000 eggs and fry in various stages of development. The male will fan the eggs to keep water circulating over them. The eggs hatch in 2 to 6 days, depending on sunlight and temperature.

The babies will stick together in a tight group as their father escorts them along the shoreline in search of food. The male will warn the group of approaching danger by splashing his tail against the water's surface. Commonly, groups of baby bowfins will combine to form aggregations up to 5 feet long and 3 feet wide. The defending males will usually hover underneath these large swarms. After a few weeks, the males will discontinue gaurding and the group will disperse.

At this time, all the baby fish have a distinct ocellus on the tail. With time, the females will lose the ring around the tail spot, and in some waters the entire spot fades away with age. Although males will outgrow the females in the first year of life. Thereafter, females will surpass them, with males only reaching a maximum length of 25 inches, as compared to the females length of up to 38 inches. As they age, the females become a dull gray or green, whereas the older males may develop some of the most vivid and striking colors of any bowfin.

In my view, the bowfin has been shown no respect for long enough. As friendly as Oscars, the bowfin is a prime candidate for aquarium life and the time is near to spawn these captivating giants in the home aquarium.


Bowfins (Family Amiidae)
written by Christopher Scharpf

Bowfins are easy to keep in the home aquarium, however their tolerance for stagnant conditions in the wild does not mean they will accept such conditions in captivity. Bowfins prefer clear, clean water, and should be kept in well-filtered aquariums. Water should be soft with a pH of 6.8, although higher alkalinities (up to pH 7.5) can be tolerated. Aquarist R. W. Wolff recommends a shallow tank with dense mats of floating plants and high-intensity lighting to sustain the plant growth. Hoover and Strange (2002) report excellent growth of 25 juvenile Bowfin in an unplanted 347 l (92 gal) Ferguson flume (a rectangular tank with internally rounded corners and a central partition that allows an elliptical flow of water through the tank).

A large adult Bowfin is hard to acclimate to aquarium life unless you are prepared to feed it live fishes. Instead, it's best to start with juveniles and let them get used to captive life at an early age. Avoid small fry, however; they can be finicky eaters that ignore just about everything except live daphnia. Juveniles 3-4 inches in length can be collected year-round with a dipnet, seine, or with an unbaited minnow trap placed into a weed bed. They do well on a diet of chopped earthworms and shrimp. Eventually they'll begin to recognize you and swim to the surface in anticipation of their next meal. This is a good time to start weaning them over to prepared foods, including freeze-dried tubifex worms and shrimp pellets. As juveniles mature, Wolff likes to vary their diet. After all, Bowfins have a varied diet in the wild. He supplements prepared foods with a meaty diet of ground beef, beef heart, and beef liver, and reports excellent color and growth. Hoover and Strange (2002) caution against feeding "non-aquatic" foods such as beef liver because they are associated with juvenile mortality; instead, they conditioned their Bowfin on 1-2 feeder minnows per Bowfin once or twice a week. Be careful how much you feed, though. Bowfins can be gluttunous, eating way more than they need or can handle. As any self-respecting predator should, they will always appear hungry, but overfeeding can lead to sickness and water quality problems (which, while not dangerous to air-breathing Bowfins, are always best to avoid). Don't worry if your Bowfin hasn't eaten in a while; one forgotten aquarium specimen survived without food for an entire year! Another word of caution: Young Bowfins can be cannibalistic, with larger specimens gulping down their smaller siblings. Make sure your specimens are all roughly the same size.

Once Bowfins settle in to aquarium life, they can become tame enough to take food from your hands. Wolff notes that Bowfin are "highly social, and you will see them holding in dense weeds, stacked together like cord wood." However, other aquarists indicate that Bowfins get increasingly territorial amongst themselves as they mature, and may need to be moved to separate tanks. Not many other fishes can be kept with Bowfins, but Wolff reports good luck with gars. Be prepared for healthy, well-fed Bowfins to quickly outgrow their tanks; an overall growth rate of 0.4 mm/day has been reported (Hoover and Strange, 2002). And be prepared for a long life; one Bowfin at the New York Aquarium lived there 30 years.

At night, when they're prowling for food, larger Bowfins may dislodge filter hoses or jump out of the tank. Should a Bowfin liberate itself, don't automatically assume it is dead when you find it the next morning. The air-breathing adaptation that allows it to survive in mud may also keep it alive during an accidental visit to your fishroom floor.

There are no reports of Bowfins spawning in aquaria, probably because of their size. However, Bowfins will spawn in large outdoor ponds if vegetation is present. The only problem aquaculturists face in raising Bowfin is providing a proper diet, since Bowfins all but ignore the pelleted feeds that are commonly used at catfish and trout hatcheries. Instead, aquaculturists prepare a "wet" pellet by placing 50% carp fillet, 40% carp guts or eggs, and 10% floating catfish fingerling feed into a food processor and grinding it into a "red goo" that sticks to your fingers.
 
Thanks. I can't wait for the first volume of Encyclopedia Oddball to be published. I'll take two sets...Paypal?


Awesome post.
 
Hmmm, I knew about Bowfins being ancient, and the breeding issue, but Oddball's information was interesting. But going back to my question, about how many gallons do they need per fish? According to what Oddball wrote they need 55 gallons or so. Was that a typo? I was thinking along the lines of 300+
 
The 55 cited in the article is recommended for juvenile specimens. These monsters grow to over 3 1/2 feet and 30 pounds. A strong 300gal (with at least a 6 ft X 3ft footprint is needed for adults.
 
Maybe wild caught but I think they are on the California no-no list.

If they aren't off limits, you can order 'em from a few places like sachs and jonahs...
 
id10t;967716; said:
Maybe wild caught but I think they are on the California no-no list.

If they aren't off limits, you can order 'em from a few places like sachs and jonahs...

yeah there illegal like everything else
 
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