7/21/11
Tanganyika Cichlids: Mouth Brooders
All over the world, shelter brooding is a common reproductive habit among cichlids. Many cichlids guard their off spring and hide them inside caves, shells or even inside the mouth of a parent. Most Tanganyika cichlids are either mouth brooders or cavity brooders. The mouth brooding Tanganyika cichlids guard eggs and/or fry inside the mouth. In some species even free swimming fry will return back to the safety of their mother's or father's mouth if they are scared or stressed, or to rest during the night. Examples of mouth brooding Tanganyika cichlids include Tropheus, Xenotilapia, Eretmodus, Cyphotilapia, Lobochilotes and Cyprichromis. The number of eggs varies significantly between the different species. A Tropheus female will rarely produce more than 5-10 eggs, while a Lobochilotes batch can include several hundred eggs.
The mouth brooding cichlids are divided into two different groups: ovophiles and larvophiles. All the mouth brooding Tanganyika species belong to the first group, the ovophiles. They pick up the eggs and guard them in their mouth until the larvae emerge. Several Tanganyika cichlid species will also let the larvae stay in the mouth until they are large enough to survive on their own. A larvophile species would instead place the eggs on a substrate and guard the spawning site until the fry emerge. The parent would not guard any eggs inside its mouth, but the newly emerged fry would be picked up and kept inside the mouth of the parent until the fry is large enough to be released.
Different Tanganyika cichlids have developed different ways of fertilization. One of the more common ways is to deposit the eggs on a substrate where they are subsequently fertilized by the male before the eggs are picked up. Other species wait until the mother has picked up the eggs, and the male fertilize them inside her mouth. In some Tanganyika cichlid species the male cichlid displays small spots on his anal fin. The female believes them to be eggs, and tries to pick them up with her mouth. Instead of getting an egg, she receives a mouthful of sperm and the eggs that are already resting inside her mouth becomes fertilized.
It is suitable to keep one male Tanganyika cichlid with three females if you want them to spawn. Tanganyika mouth brooders are however quite easy to get into spawning condition, and successful spawnings frequently occurs even in aquariums where one male Tanganyika cichlid is kept with only one female. If your Tanganyika cichlids refuse to spawn, taking them off their dry prepared food diet and give them live or frozen food instead will usually trigger spawning.
After fertilization, the eggs of mouth brooding Tanganyika cichlids will typically be incubated for 30 days if the water temperature in the aquarium is kept in the 82-86°F (28-30°C) range. Keeping brooding Tanganyika cichlids in a large aquarium is recommended, since a small aquarium will increase the risk of aggressive behaviour towards to brooding fish. The aquarium should also provide the brooding cichlid with plenty of hiding places to relieve stress. You should avoid moving a brooding Tanganyika cichlid to its own aquarium, since the stress from being caught and moved can cause the cichlid to spit out its eggs or fry prematurely. A mouth brooding Tanganyika cichlid will still be capable of eating while the eggs and fry is kept in its mouth, and this is probably an important food source for the newly hatched fry. Most Tanganyika cichlid species while release the fry when the fry are around seven days old. Your newly released fry can eat Daphnia, Artemia nauplii or crushed flake food.
The mouth brooding cichlids are divided into two different groups: ovophiles and larvophiles. All the mouth brooding Tanganyika species belong to the first group, the ovophiles. They pick up the eggs and guard them in their mouth until the larvae emerge. Several Tanganyika cichlid species will also let the larvae stay in the mouth until they are large enough to survive on their own. A larvophile species would instead place the eggs on a substrate and guard the spawning site until the fry emerge. The parent would not guard any eggs inside its mouth, but the newly emerged fry would be picked up and kept inside the mouth of the parent until the fry is large enough to be released.
Different Tanganyika cichlids have developed different ways of fertilization. One of the more common ways is to deposit the eggs on a substrate where they are subsequently fertilized by the male before the eggs are picked up. Other species wait until the mother has picked up the eggs, and the male fertilize them inside her mouth. In some Tanganyika cichlid species the male cichlid displays small spots on his anal fin. The female believes them to be eggs, and tries to pick them up with her mouth. Instead of getting an egg, she receives a mouthful of sperm and the eggs that are already resting inside her mouth becomes fertilized.
It is suitable to keep one male Tanganyika cichlid with three females if you want them to spawn. Tanganyika mouth brooders are however quite easy to get into spawning condition, and successful spawnings frequently occurs even in aquariums where one male Tanganyika cichlid is kept with only one female. If your Tanganyika cichlids refuse to spawn, taking them off their dry prepared food diet and give them live or frozen food instead will usually trigger spawning.
After fertilization, the eggs of mouth brooding Tanganyika cichlids will typically be incubated for 30 days if the water temperature in the aquarium is kept in the 82-86°F (28-30°C) range. Keeping brooding Tanganyika cichlids in a large aquarium is recommended, since a small aquarium will increase the risk of aggressive behaviour towards to brooding fish. The aquarium should also provide the brooding cichlid with plenty of hiding places to relieve stress. You should avoid moving a brooding Tanganyika cichlid to its own aquarium, since the stress from being caught and moved can cause the cichlid to spit out its eggs or fry prematurely. A mouth brooding Tanganyika cichlid will still be capable of eating while the eggs and fry is kept in its mouth, and this is probably an important food source for the newly hatched fry. Most Tanganyika cichlid species while release the fry when the fry are around seven days old. Your newly released fry can eat Daphnia, Artemia nauplii or crushed flake food.
Tropheus sp "black ikola" a mouthbrooder from lake Tanganyika.
Newly released fry is comparatively small and there is always a risk of them being eaten by other fish in the aquarium. Some Tanganyika cichlid breeders will therefore force the parent fish to spit the fry, since this makes its possible for the breeder to know exactly when the release takes place and promptly isolate the fry from the other fish. Forcing a fish to spit out its fry is naturally very stressful for the fish, and force opening its jaws can also cause a lot of physical harm. A safer, but still quite stressful, way of protecting the fry is to use a net cage or breeding trap. The parent fish will however still fell very stressed since it first have to be caught and then contained in a space much smaller than what it is used to. Trapping the brooding fish will usually make it spit its fry before long, and you should therefore wait as long as possible before you do it. Fry from a mouth brooding Tanganyika cichlid that is allowed to keep its fry full-term are quite large, and you can usually catch them without much problem. If the release takes place in the community aquarium, and not in a net or fry trap, you will therefore be able to remove the fry
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