Steckbrief Banggai-Kardinalbarsch

Der Banggai-Kardinalbarsch (Pterapogon kauderni) – often simply called cardinal fish or kauderni – is native to the Indian Ocean and impresses with its unique and extravagant appearance: the body shape with the high back is flattened at the sides and the mouth is large and slightly higher. The sides of the body shine silvery-white and are crossed by two robust matte black transverse bands. A third transverse band extends over the large eyes and mouth. The tail shows a very deep furrow, and there are also deep black longitudinal bands on the upper and lower lobes. All fins, flanks and caudal stalk feature a pattern of bright white spots, which create an individual pattern and make each animal unique. Because this design actually differs from animal to animal and serves, so to speak, as an identifying element

By the way, the Banggai cardinalfish was discovered in 1920 by the Swedish researcher Walter Alexander Kaudern, who sent two specimens of this captivatingly beautiful fish to the then National Museum of Natural History in Leiden. The species was first scientifically described in 1933 and named Pterapogon kauderni in honor of its discoverer. Subsequently, however, the Banggai cardinalfish was completely forgotten. It was only rediscovered in 1996, so it was initially assumed that a previously unknown species had been encountered. However, the misunderstanding was soon clarified and the Pterapogon kauderni quickly won the hearts of aquarium enthusiasts thanks to its unusual and extravagant appearance. After its exhibition at the Interzoo trade fair in Nuremberg, it became more and more popular and the demand for the beautiful fish increased rapidly.

Due to their very limited distribution area and the high demand for ornamental fish by the commercial trade, Banggai cardinalfish have long been considered at risk of extinction. If you are still thinking about adding a couple of these rare and beautiful fish to your underwater world, you should make sure when purchasing that your specimens come from captive breeding.

You can find all the information you need to know about the Banggai cardinalfish, its keeping, care, feeding and reproduction in our profile.

Origin

The original habitats of the Banggai cardinalfish are located east of the Indonesian island of Sulawesi; can be found there, for example. B. around the islands of Banggai, Bandang, Kembongan and South Peleng. Within this distribution area, Kauderni prefer to live in seaweed beds, mangroves, lagoons and coral reefs in very shallow water, from half a meter to 4.5 m, with a temperature between 28° and 31°C. Because of this lifestyle, the effective range of the Banggai cardinalfish and its isolated populations is limited to an area of ​​only 34 square kilometers.

^{In its native habitats, isolated populations of the Banggai cardinalfish are found only in very limited distribution areas.}

Since this visually striking fish was (re)discovered for aquarium use in the late 20th century, it has been considered an extremely popular ornamental fish: it is estimated that several hundred thousand Banggai cardinalfish are taken from the wild every year for commercial purposes, an incredibly high number of which do not even survive transportation.

The small distribution area of ​​the Banggai cardinalfish and the commercial trade in chewing fish for aquarium purposes endanger the existence of the species, so much so that it has been listed as an endangered species on the International Union for Conservation of Nature (IUCN) Red List since 2007.

Therefore, you should always make sure that your Kaudernis come from offspring. Since Banggai cardinalfish are also very easy to keep, there is no reason to resort to wild capture.

Behave

In its original habitats, the Banggai cardinalfish lives in very shallow water, in seaweed beds, mangroves, coral reefs or lagoons. Juveniles form large groups of up to 500 individuals and then seek protection from predators in the long spines of diadem sea urchins. However, adult animals often live in smaller groups.

In the aquarium, however, the Banggai cardinalfish shows completely different behavior from its original lifestyle: if they are raised in a larger group in the home aquarium, the beautiful fish can develop strong aggression towards each other as they age. The population then quickly depletes as individual animals die from stress or are killed by their peers. In the end, usually only a male and female pair remains. For an aquarium it is therefore expressly recommended to keep them in pairs.

In your underwater world, your Kaudernis pair exhibits a very reserved demeanor and appears very calm. Instead of actively swimming, Banggai cardinalfish become more withdrawn and may even appear a bit listless. However, there is movement in the tank when there is food. Banggai cardinalfish generally socialize well with other calm fish. However, coexistence in the underwater world is determined more by mutual ignorance than by interaction.

Fish-friendly accommodation and assistance

As already described, Banggai cardinalfish should always enter the underwater world in pairs, as they can show aggressive behavioral tendencies in larger groups. A seawater aquarium with a capacity of 300 liters or more offers sufficient space; the water temperature should be between 27° and 30°C. Additionally, sufficient filtration is needed to ensure easy water movement.

Socialization with other very peaceful fish species is certainly possible and usually works without problems. Your caviar likes to be in close proximity to shelters and other hiding places, so your aquarium should have suitable facilities. From its hiding place, a Banggai cardinalfish closely observes its surroundings, if a potential feeding opportunity opens up, it becomes active and can then move across your tank in a lightning-fast motion.

Nutrition

In nature, Kaudernis feed on zooplankton, e.g. B. by copepods, small decapods, marine isopods as well as eggs and larvae of various maritime animals, of which copepods constitute the major part of their food. When it comes to feeding in your underwater world, Banggai cardinalfish prove to be easy-to-please breeders and are happy to make do with brine shrimp, brine shrimp, and almost any other type of food; They also like to see frozen Mysis on their menu.

Playback

Banggai cardinalfish are paternal oral breeders, where the father is responsible for carrying and incubating the fertilized eggs in the mouth until they hatch. The peculiarity of cardinal fish is that the young fish do not go through a larval phase, but hatch from the egg immediately after the metamorphosis has been completed.

Once a pair of Banggai cardinalfish has reunited, the female (also Rogner) begins courtship around the male (also Milchner), who is often a bit shy at first. To demonstrate her interest and willingness to reproduce, the female constantly swims under the male’s caudal fin. This courtship dance can last several hours or even longer, during which the female repeats her courtship up to a hundred times. It almost seems that the male needs to be convinced, as he will have a stressful period ahead of him as he will not eat during the reproductive phase which will last up to a month. The act itself, that is, the delivery of the eggs from the Rogner to the Milchner, lasts only a few seconds. The couple then enters the post-courtship phase, which lasts approximately 30 to 60 minutes. During this time, the two fish swim around each other and spin around, trembling. It can be assumed that the eggs are now inseminated. The clutch consists of approximately 5 – 25 small orange eggs, which the male will now carry in his mouth. After three weeks, the babies hatch and remain in their father’s mouth for another six to ten days. When this releases the young fish into the wild, they already have a size of up to 6 mm. The care of the brood by the parents is now complete.

Due to the lack of the larval stage, drifting of the young fish does not occur, as occurs with most other fish species. This also explains the limited distribution area of ​​the Banggai cardinalfish. It often happens that the larvae of small fish do not remain in the place where they lay their eggs, but are washed up or transported to distant places as part of the plankton to form new populations or expand the distribution area of ​​the respective species.

Fragen zum Banggai-Kardinalbarsch

1. How big do Banggai cardinalfish get?

The Banggai cardinalfish can reach a maximum body size of eight centimeters, with males and females no different.

2. Sind Banggai-Kardinalbarsche Maulbrüter?

Like all cardinal fish, Pterapogon kauderni is a paternal oral breeder, where the father is responsible for carrying the eggs in his mouth until hatching and for a few days beyond. However, the so-called planktonic larval phase does not occur in the offspring of the Banggai cardinalfish. If the father releases the young fish into the vastness of the ocean, they already have a size of up to 6 mm, so that there is no drift and the young fish remain more or less in place. This peculiarity also explains the small distribution area and the extensive isolation of the individual populations of the Banggai cardinalfish.

3. Are Banggai cardinalfish suitable for beginners?

Banggai cardinal fish prove to be fairly easy-to-care-for inhabitants of your underwater world and can therefore also be suitable for beginners, but a little experience in the field of marine aquariums can still be very useful to be able to take care of your cat in the best possible way.

4. How many Banggai cardinal fish should you keep?

The beautiful Banggai cardinal fish should always be kept in pairs.

Keeping them alone is in no way fish friendly and would lead to isolation of your fish. Although Banggai cardinal fish live together in sometimes very large groups in nature, it is not possible to keep them in groups in the aquarium because the animals show unusually aggressive behavior. They begin to attack and hurt each other, so that most of the animals succumb to their injuries or die due to the stress resulting from the overall situation. In the end, in most cases, only one couple remains that has prevailed over the others.