Video and text ownership: Abdel Rahman El Gamal
This video was taken at the Sea World – California – USA
Introduction: Ichthyologist Dr. Frederick Petrus Koumans he is the one who described the species and erected a new genus, Pterapogon (cardinalfish with long fins), and assigned the species name of kauderni in honor of the Swedish zoologist Walter A. Kaudern who was the first to collect this species in 1920. It is among the relatively few marine fish to have been bred regularly in captivity, but significant numbers are still captured in the wild and it is now a threatened species. The Banggai cardinalfish is the only representative of the family that is diurnal.
Description: The Banggai cardinalfish (Pterapogon kauderni) is a small tropical cardinalfish that belongs to the family, Apogonidae. This attractive fish is popular in the aquarium trade. The Banggai Cardinal has a distinctive pattern of color with a remarkable arrangement of vertical bars and white spots. The beautiful color along with elongated fins in addition to its small sizes (a maximum total length of about 8 cm), explain the popularity of the Banggai cardinalfish in the aquarium trade. Although there is no distinct difference in color pattern between male and female, males have enlarged buccal cavity during the incubation of fertilized eggs till hatching.
Distribution and habitats: This species has an extremely limited geographic range and is originally found only at select sites around the coasts of 33 islands in the Banggai Archipelago of Indonesia. It is estimated that the total suitable habitat available within the Banggai cardinalfish’s range amounts to a mere 34 square kilometers.
The Banggai cardinalfish are more common in shallow waters at 1.5–2.5 m depth inhabiting various habitats such as seagrass beds, coral reefs in association with the seagrass Enhalus acoroidesand and long spined Sea Urchins, Diadema setosum.
Feeding habits: In nature, the Banggai cardinalfish are an opportunistic species that feeds principally upon tiny planktonic crustaceans whereas Copepods constitute a bulk of their diet. They feed also on variety of small organisms from the water column and the seabed, including marine worms, molluscs and fish larvae as well as preying on the larval stages of coral reef fishes’ parasites. Males carrying eggs do not eat throughout the incubation period.
In aquariums, the wild caught Banggai cardinalfish are fed meaty foods, including chopped seafood, adult brine shrimp, and Mysis shrimp. Feed is provided just before lights out, leaving a dim light. Enriching the artemia may be practiced several hours before they are fed to the cardinalfish.
On the other hand, the Banggai cardinalfish in nature is preyed upon by various species, such as the crocodile fish, various lion fish species, moray eel, stonefish, sea snake, and grouper.
Reproduction: The reproduction of the Banggai cardinalfish in nature is considered an easy process. The female begins the courtship before choosing a male partner and then after the pair, separates from the group and establishes and defend their own territory.
The Banggai Cardinalfish reaches their sexual maturity in about 10 months of age. The female spawns about 50-90 eggs with an average of about 75 eggs of about 2.5 mm in diameter. Eggs are quickly swallowed by the male, fertilized and incubated in a special pouch inside the male’s mouth whereas the male takes care about the embryos till hatching. The incubation lasts about 20 days. Hatched embryos continue for additional 10 days in the male’s mouth pouch till the reach 5-6 mm in length and develop into miniature versions of the adults. By then, young are released into, and hide among the spines of the long-spined sea urchin. During the 30-day brooding period the male does not eat.
Threats and conservation status: The first international trade of the species as an aquarium fish was in 1995–1996. The growing demand on the species as well as its premium prices led to the overfishing throughout the archipelago as well as attempting to raise it in captivity. Over few years of collection, the populations of the Banggai cardinalfish showed a drastic decline reaching close to extinction in some of home islands. This situation necessitated the reproduction of the species in captivity that which was done successfully. However, it appears that the demand on the species exceeds the available fry whether collected from the wild or produced in captivity.
According to the IUCN standards, the Banggai cardinalfish was listed as Endangered on the IUCN Red List of Threatened Species in 2007.
References: Wikipedia, Fish Channel.com, Fishlore (Aquarium Fish Information), ARKIVE, Aquarium Explorer, IUCN Red List of Threatened Species, Banggai Rescue, Acebook