Fish

Out the over 2,000 traded coral fish species, about 24 million specimens are traded, without counting the fish that perish during capture and transport.

Cartimar-and-Marine-Fish-Exporter-by-Gregg-Yan-Tight

Often only very little – or nothing at all – is known about the biology of these species. It is therefore very difficult to assess the impact of the catch data on the fish population.

Damselfish (Pomacentridea) seem to be the most traded species and account for almost half of the trade. Other species that are often traded are angelfish (Pomacanthidae), surgeonfish (Acanthuridae), wrasses (Labridae), gobies (Gobiidae) and butterflyfish (Chaetodontidae).

BanggaiReduced distribution, small population
Example: Banggai cardinalfish (Pterapogon kauderni)

The Banggai cardinalfish only lives in small populations in a very small region of about 23 km2 in the North East of Sulawesi (Indonesia).

Rare or endemic fish (fish that are prevalent in or peculiar to a particular locality or region) get higher prices.

Although this fish can successfully be bred in captivity, wild specimens are cheaper. Therefore, banggai cardinalfish are mostly taken from their natural environment. Read article (in German).

Biondo_PutzerlippfischKey species
Example: Bluestreak cleaner wrasse (Labroides dimidiatus)

The Bluestreak cleaner wrasse cleans coral fish, keeping them parasite-free. They represent a key species for biodiversity in the reef. Research has shown that the lack of this species is followed by a rapid degeneration of the coral reef community just four months after its removal.

This species tends to fare poorly in aquarium conditions unless kept with a large community of fishes. They are not likely to accept substitute food, hence aquarists are advised to avoid keeping them.

palette-surgeonfish_pixabayExample: Palette surgeonfish (Paracanthurus hepatus)

The Palette surgeonfish is very valuable. It can easily reach 40 cm in length and be too big for private aquariums. It reacts aggressively toward other doctorfish or coral fish. It feeds on zooplankton and needs a continuous intake and is prone to disease.

The Palette surgeonfish became famous through the film „Finding Nemo“. In 2016 Walt Disney will be airing “Finding Dory” featuring a Palette surgeonfish. As was the case with the leading “actor”, the anemone fish in “Finding Nemo”, it is now expected that the trade in Palette surgeonfish will explode.

But in difference to anemone fishes Palette surgeonfish do not reproduce in captivity. Every Palette surgeonfish comes from the wild – the coral reef.

Changes in age dynamics
Example: Parrotfish (Scaridae)

It is often juvenile, sexually immature fish that are caught for their peculiar colouring or because they are smaller and can easily fit in an aquarium. Hence, they will not contribute any offspring to their original population, which in turn will change its age dynamics.

This juvenile Dichromatic parrotfish (Cetoscarus bicolor) is 12 cm long. As an adult it will reach 90 cm – keeping it in an aquarium at that size is impossible.

Synchiropus_splendidus_maleSex ratio and size differences
Example: Mandarinfish (Synchiropus splendidus)
This fish is traded frequently because of its special colour. In the wild some populations are thought to be extinct.

It is not easy to keep Mandarinfish in captivity. The male Mandarinfish are normally the most caught due to their size. This preference has led to a shift in the whole population biology of the species and a change in sizes. Research shows that nowadays males are only 3 cm long compared to 6 cm in the past. Female Mandarinfish and aquarium owners alike, prefer bigger males. How will the females react when faced with only smaller males?

The Mandarinfish are caught with a hand spear, which can injure or kill them. Dealers say the injury heals fast. Watch film (from 5.08).

The Mandarinfish has a specialized diet of live zooplankton, which is more difficult to replicate in captivity. As a result, wild caught Mandarinfish often refuse to eat and starve to death within a few weeks of purchase.

Chromis_viridis_2011Feeding
Example: Blue-green damselfish (Chromis virdis)

The Blue-green damselfish, is the most traded coral fish. The US alone imports nearly one million individuals per year. Poor collection and transport methods cause high mortality rates. In the main exporting countries Indonesia and the Philippines stunning with cyanide is still used frequently – although illiegal – which claims especially with the Blue-green damselfish high mortalities.

In its natural environment it lives in a school in a coral head and constantly feeds on live zooplankton. In an aquarium, feeding takes place at regular intervals, which disrupts the cohabitation with its fellows.

Dascyllus_aruanus_Wikipedia_Leonard_LowFights
Example: Whitetail dascyllus (Dascyllus aruanus)

The Whitetail dascyllus is also one commonly traded coral fish. It defends its territory – a coral head that offers vital protection – against intruders. In an aquarium, where there is no possibility to retreat to a coral head, territorial fights are often fatal.