The Polypterus Senegalus, sometimes called the Senegal Bichir, Reed Fish, Dinosaur Eel, or Swamp Dragon, is not your garden variety aquarium fish. With their serrated dorsal fins, pronounced teeth, protruding nostrils, and wide, iridescent eyes, it is easy to understand why some people call Polypterus senegalus the Swamp Dragon.
- Frequently Asked Questions
Though these fish somewhat resemble eels as well, they are not related. Any common names linking the Polypterus senegalus to eels are misnomers. These fish have characteristics that are truly unique to the Polypterus genus.
The Polypterus senegalus comes from heavily vegetated, slow-moving water systems in Africa and India. They are very common in these areas, so common, that they are often found in roadside ditches. These fish are predators that lay in wait for their prey amongst vegetation in murky waters.
These Swamp Dragons grow to be 30 cm long. These fish hunt by smell, and therefore have long, protruding nostrils (much like a dragon) to pick up the scent of their prey. The swamp dragon is covered with thick scales (unlike eels, as eels are scaleless). These scales serve as armor to protect the Swamp Dragon from injury.
The Senegalus has a modified swim bladder that acts as a primitive lung. This allows the Swamp Dragon to directly breathe oxygen, and they will often shoot up to the surface for a gulp of air. These fish, as long as they stay wet, can survive for extended periods of time out of water.
The Polypterus is not picky about its prey and will eat almost anything. Even if a fish is a bit too large to be swallowed, the Polypterus senegalus may try anyway. This is why tankmates have to be at least half the size of the swamp dragon.
My favorite food for Senegalus, which can be ordered cheaply on Amazon:
Luckily, the Senegal Birchir will eat other foods besides live feed. Pellets that sink to the bottom are readily eaten by them, as are freeze-dried, frozen, and even flake foods. If Polypterus senegalus is fed primarily prepared diets, the predatory behavior they can exhibit is kept to a minimum, allowing the aquarist to keep smaller fish with the swamp dragon.
The Polypterus senegalus is referred to by a number of different common names and is often confused with eels. Swamp dragons, though, are truly unique fish, and perfect for the aquarist who wants to add a little mystery to his fish tank.
Swamp Dragons are quite hardy and can tolerate a wide variety of water conditions, but this should not be an excuse to forgo regular aquarium maintenance. Water temperatures should be between 25-29ª C.
Since the Senegal Birchir reaches a fair size, it should have an aquarium of no less than 20 gallons. The Swamp Dragon is one of the few fish that are appropriate for tall and hexagonal fish tanks because their primitive lung allows them to thrive in oxygen-deprived water.
This primitive lung, as mentioned in the previous paragraph, causes the Polypterus senegalus to dart up to the surface of the tank for a gulp of air. As the Swamp Dragon does this, it often shoots right out of the tank, condemned to a slow, painful death, drying out on the floor. For this reason, every gap in the hood of an aquarium meant to house the Swamp Dragon should be covered, as they seem to be able to slip out of the smallest spaces.
Though the Senegal Birchir is a voracious predator, it is an otherwise peaceful fish. Swamp Dragons can be kept in groups. As long as other fish are too big to be seen as prey (at least half the size of the Swamp Dragon) the Polypterus senegalus can coexist peacefully with other species.
Frequently Asked Questions
1. Will bichir eat other fish in the tank?
Yes, bichirs are predatory fish and will eat smaller fish in the tank if they can fit in their mouth. Therefore, caution should be taken when choosing tank mates for bichirs. They should not be kept with small, delicate, or slow-swimming fish. Suitable tank mates for bichirs include other similar-sized and equally aggressive fish such as larger cichlids, catfish, and some other types of bichirs.
2. Can bichirs eat goldfish?
Yes, bichirs are opportunistic feeders and will eat goldfish if they are small enough to fit in their mouths. However, feeding goldfish to bichirs on a regular basis is not recommended as goldfish may not provide the proper nutritional value that these fish require. Bichirs need a varied diet that includes live or frozen foods such as worms, insects, crustaceans, and small fish.
3. Are dinosaur bichirs aggressive?
Dinosaur bichirs, also known as Polypterus endlicheri, can be aggressive towards their own species and other fish in the tank. They have a strong territorial instinct and may become aggressive towards other fish that invade their space. It is not recommended to keep them with peaceful community fish. Suitable tank mates for dinosaur bichirs include other similar-sized and equally aggressive fish such as larger cichlids, catfish, and other bichir species.
4. Do dinosaur bichirs hide?
Yes, dinosaur bichirs are nocturnal and will hide during the daytime. They are sensitive to bright light and prefer to stay in the shadows or undercover. Therefore, providing them with hiding places in the tank such as caves, rocks, and plants is important. This will also help to reduce stress and make them feel more secure.
5. Do bichirs eat at night?
Yes, bichirs are nocturnal feeders and are more active at night. They typically hunt and feed during the night time and rest during the day. Feeding bichirs at night is recommended as this is when they are most active and will be more likely to eat.
6. Why do bichirs jump?
Bichirs may jump out of the tank if they feel stressed or threatened. This can be caused by a variety of factors such as poor water quality, aggressive fish, overcrowding, or low oxygen levels. Providing a tight-fitting lid on the tank is important to prevent bichirs from jumping out and injuring themselves.
7. What are good tank mates for bichirs?
Good tank mates for bichirs include other similar-sized and equally aggressive fish such as larger cichlids, catfish, and other bichir species. It is important to keep in mind that bichirs are predatory fish and may eat smaller fish in the tank if they can fit in their mouth. Therefore, caution should be taken when choosing tank mates.
8. How to know if my bichir is male or female?
Determining the sex of a bichir can be challenging, especially when they are young. However, mature female bichirs tend to be larger, rounder, and have a more prominent genital papilla than males. Males, on the other hand, are generally slimmer and have a more pointed genital papilla. It is recommended to observe the fish closely and look for these differences to determine their sex.
Do you have any experience with the Dinosaur Bichir? Share your thoughts below!
I just purchased a dinasaur bicher….thought it was a dragon goby (at this time I didn’t know dragon gobies were brackish) or I would have questioned what this fish really is since it was in a freshwater tank at the pet store. At the same time I also purchased 2 red tail sharks. I was told these would all be fine in the same tank, and had also mentioned I am putting these in a 20 gallon until I get the 30 gallon tank ready. In the meantime, I’ve been looking up info and when I went back to the store I was also told they never had dragon gobies…and that what I purchased was a dinasaur bicher. Now in my research I see these get much bigger..and is actually too much for even my 30 gallon tank. And in more research I am not sure that if I keep all..this dinasaur bicher may eat my red tail sharks?? Am looking for more input on this.
I don’t have any experience with red tail sharks. You might have problems, yes. Bichirs are not that aggressive, but they might eat smaller fish.
I’m sure you’ve already resolved this issue since this was in September but I wanted to give you my input. I have had my bashire since he was very small and he’s been housed with smaller fish the entire time with no problems. He even seems to be the sweetest one. Even greeting me when all the others run and hide. I have African cichlids. 2 of the fish are much smaller rainbow cichlids and they just swim around like they’re all the same thing. He actually acts like a dog greeting you when he wants fed or when you talk or anything. He walks around on his front fins like they’re legs. He is however getting very long but he’s skinny and doesn’t take up much room at all. Very good and cool fish.
Erm so it’s 2019 so all your issues may have been solved but my Senegal is about 9 inches and still growing. I’ve fed him pellets to shrimp to live and it’s all worked. Currently he’s in a 15 gallon tank by himself and he’s happy in that. Also red tail sharks only get about 5 to 7 inches long and they might get eaten depending on what species Bichir you got which appears to be the Senegalus species. Good luck
Yo you can call me on more info I know quite a bit about it 7125354662
The Bircher will far outgrow the Red tail’s and they will in time become prey.
they will eat any fish smaller than they are.I have 1 about 6 inches maybe little longer an ive been feeding it silver sides.beware what you feed it or it will grow fast.I found out the hardway.no more silversides for awhile.
HELP! My bichir eats Rosy minnows as food and there are often times 2000 in the tank so he can eat as he pleases. There are also ghost shrimp in the tank that he eats whenever they give birth. In the last month My Bichir gotten huge! Is he sick, have clogged intestines, or just over eating? Please let me know, the students in my class room are very concerned (as am I.) I have photos I can share if you’ll let me know how to add them to the post.
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My Rex has a Turtle Tank mate and they love living with each other. Neither have any interest in each other as far as food goes, but they are happy to live together.
Recently I noticed little sticky clear egg like things in the corner of my tank and my bichirs went nuts when I tried to clean the tank, what do their eggs look like?
I have 2 dinosaurs. I believe one has recently become pregnant. How long is the pregnancy and should I separate them?
Hi Katie. Isn’t it a bloat? Senagalus don’t have internal fertilization. They just lay the eggs.
Hi my dinosaur fish is shedding is that normal and I also see red streaks down the sides like blood
Hi I just recently purchased a Bichir and added it to my 55 gal tank. In this tank there are 2 large angel fish and a red tailed shark. He lasted two days, then died. I am truly crushed, I really liked this fish and found it very unusual. He was the last one for sale in that pet store. Do u have any idea to what I did wrong? I keep my tank heated I left him in the bag that I brought home from the pet store, and let the it float for almost 20 mins before letting him out. Could u please give me some advice, I wud like to purchase another one.
I’ve had my Dino Eel for almost a year now. When looking back at the pet store I can hardly believe he was barely 2 inches when I got him. Now about 9 months later he is almost 8 inches long. They are not as territorial as I suspected given their size. However it is fact he will eat anything that will fit somewhat in his mouth.
I have gotten myself a dinosaur bichir a few months back and now he is roughly 7 inches long. I have only fed him shrimp pellets and recently got 5 Chinese leaches to help with algae. 3 of the leaches came up missing and I am pretty sure it was my Bichir. The 2 that survived were the 2 biggest of the 5. They’re thriving greatly. I just got a 2nd Bichir in Hope’s I will have a Male and a female. The 2nd bichir is merely an inch long still a baby. Hopefully it’ll grow fast and they’ll breed. My tank mates include a pleco, Angel fish( I had 3 and 2 mysteriously died, no idea why) 2 Chinese Loaches, and some Dutch fish we caught in the grass after a rain shower. I was concerned about bichir cannibalism but they seem to be getting along fine. I absolutely love my Bichirs and would like to get another aquarium just for 2 more. Thank you for this read, was wondering my mine biggest Bichir kept swimming to the top and now I know!!
i just got one 2 weeks ago and didn’t know they eat other fish. I had a feeder fish in the tank that outgrew for my bigger fish to eat it, but not for my Senagalus. Last night he grabbed the fish and after a while the Senagalus swallowed it whole. it was almost like when a snake devours its prey whole. now he seems calm. I may need to get more feeder fish for it
So a 20g is way too small for start, I think stores should keep them in no less than 40gb…Just wanna stress that a lower wider tank is better, especially when they are juvenile.
For 2 reasons,
1- Less distance to go to surface for use of their spiracles (probably spelled wrong lol) when accessing surface air.
Also more general oxygen in a lower tank so they will go less often to surface, but will still do so.
2- more footprint is best when keeping more than 1, even if they come from same batch from store. They can get aggressive towards eachother.
Some random thoughts:
Filtration for us has been the sponge filter. Main reason for this is that they prefer slower, calmer waters. Sand substrate as they love to sift, and plants like Anubias, Echinodorus or Vallisernia are excellent choice.
Live feedings every now and then will simmer tempers when keeping more than 1 of the P.Senegalus.
Awesome read, really enjoyed this article. Best part is it’s free, and information in this hobby always should be!
Hi, I bought a “dinosaur loach” about 3 years ago and originally had it in my 20 gallon tank. It ate a few of my snails and eventually got large enough for me to put it in our 50 gallon. Ate a few of my fish there. It continued to grow so we put it in our 100 gallon until it ate a fish about 13 inches long. At this point our “dinosaur loach” was about 2 feet long so we put it in a horse trough we converted into a tank. He is still alive and is about 2.5 feet long. Not sure what he is anymore.