The blue parrotfish (by Xiao Xiao 8B)
The only uniformly blue species of fish known.
The blue parrot fish is found in the associated waters of the Atlantic Ocean,Western Atlantic,Brazil,Bahamas,Bermuda and the West Indies. In fact they are the second largest parrotfish species in the Caribbean. They are uniformly blue and have a yellow spot in their heads that fades as they grow older. They average 30-75 cm in length. Male specimens can grow to up to 120 cm. Large fish develop a big snout. No other species has this uniform blue color in adults. The blue parrot fish spends 80% of its time searching for food. They eat algae and graze off coral. The digested food is then pass out as sand.
The blue parrotfish doesn't face many threats in the wild. Even though large specimens are targeted by fishermen, there seems to be no evidence of apparent global decline in population. Sometimes they are not directly targeted but rather caught as a bycatch, often within the traps set for grouper.
Parrotfishes cross-fertilise. The egg is fertilised both internally and externally. When the egg is fertilised internally, it is preceded by an elaborate courtship display from the pair. Parrotfishes are born female, but as they mature, they turn into males. Females will also turn into males if the local male population decreases dramatically. This strategy is very useful when group spawning because many parrotfishes will die young, but since they are female, they can then lay eggs for the males to fertilise later.
DID YOU KNOW that the blue parrot fish is considered a delicacy in many countries. people see raw blue parrotfish meat as 'royal food', once eaten only by the king.
The blue parrotfish unusually spawns all year-round, with the peak spawning period being summer. The females get fertilised and later drop their eggs in the water. The eggs become part of the plankton until the they hatch. Fertilised eggs begin to hatch 25 hours after they are released into the water. Although no research has been conducted yet on the number of gametes parrotfish produce, they will lay hundreds of eggs. The large number of eggs is an advantage as many of the eggs may not me fertilised. Some may also get lost in the plankton or get eaten by other fishes.
The development of the embryo in parrotfishes are, like most other fish, external. Parrotfishes are oviparous; they can fertilise eggs both internally and externally, They lay eggs (babies aren't born strictly alive) and many don't make it too adulthood, let alone hatching or get fertilised.
The gestation period for parrotfish eggs are quite short, being only a little more than a day (25 hours) after fertilisation. Newly hatched larvae begin to feed after three days. Most parrotfish species develop rapidly and reach maturity between two and four years.
There are both good and bad sides to the external development of the embryo. On the positive side, the fish that laid the eggs can be productive and produce more offspring while the eggs develop somewhere else, since parrotfishes spawn all year round anyway. Developing outside of the body can also help disperse the eggs and prevent fishes mating with its siblings.
On the negative side, he eggs won't receive the protection internally developed animals. The eggs may get washed out too far away from the reef in the plankton they float around in; the blue parrotfish doesn't attach her eggs onto a stationary object. The eggs are also easy prey for other animals.
There is no evidence of parental care among parrotfishes. This is probably because of the stable environment in which the parrotfish lives in. With the conservation status of 'Least Concern' on the IUCN Red List, this species is not threatened at all and live in harmony amongst other reef fishes. As you can see, there is barely anything parent fishes could worry about or teach their offspring as being a simple species, they are born with many natural instincts.
FACT The blue parrotfish has developed a very unique survival strategy. Just before they go to sleep at night, they secret a type of mucus jelly from a gland on their head (hence the large forehead) and engulf themselves in the 'sleeping bag'. This 'sleeping bag' will hide the fish's scent from nocturnal predators so the fish can have a good night's sleep. It also acts as an early warning system to warn the fish when something disturbs the jelly.
Parrotfishes are r-selected species. Although they can reproduce more than one in their lifetime and are quite large, they release lots of small eggs, most of which don't survive. (emphasis on quantity not quality). Adult fishes also don't need to bring up their offspring as many eggs are laid, just in case something goes wrong and many don't survive. (unlike most k-selected species that rely on parental care due to the small number of offspring) This is also a good way to ensure that only the fittest and wisest offspring survive to be able to produce another healthy generation.
http://www.greatbarrierreefs.com.au/biobits/biobits_parrotfish.htm http://answers.yahoo.com/question/index?qid=20080329174841AA8aThV http://wiki.answers.com/Q/Are_parrots_internal_or_external_fertilization http://animaldiversity.ummz.umich.edu/accounts/Scaridae/ http://www.iucnredlist.org/details/190709/0 http://www.fishbase.org/summary/1153
Thank you for the patience of reading my tackk. Here is a reward for you. Very funny and cute video of someone feeding bread to blue parrotfishes. (Are you even allowed to do that in the ocean?) Anyway, ENJOY!
Stop at 0:32 one of them makes a funny noise :D