Reef Parrotfish (Scaridae sp.)
Katerina Skeparnis
“When resources become skimpy, human beings don't suddenly cooperate to conserve what's left. They fight to the last scrap for possession of a diminishing resource.”
- Deepak Chopra |
Taxonomy
Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Perciformes Family: Labridae Genus: Scaridae |
The parrotfish is a very unusual group of reef fish. The parrotfish is a tropical reef fish found in the Caribbean and Indo-Pacific oceans. They are a very diverse genus of reef fish containing 500 – 600 different species. They are very colorful and the coloration is different for each species and between the genders and life stage in each species. They range in size from as small as your hand to as big as a person. They eat coral and the algae on the coral and excrete sand as a waste product. They have a cool life cycle in which they are sequential hermaphrodites, and the females fight to become the dominant male. They create a mucous bubble to sleep in at night which makes them very vulnerable to night spearfishing. They are a relatively new fishery species. As the traditional carnivorous fishery species become more scarce to the point of being commercially extinct the parrotfish are becoming more popular. As the carnivorous fish become more and more over fished are the parrotfish and other herbivorous fish going to face the same fate? There needs to be precautions taken now to prevent the extinction of the more popular reef fisheries and prevent the parrotfish from becoming a major commercial reef fishery.
html:www.reefresilience.org
From their shape, color, and size to their behavior, the diversity of coral reef fish makes them very popular with scuba divers. On the Great Barrier Reef there are 500 – 600 different species of coral reef fish. [16] The most common type of fish is the boney fish which have hard bone structures for support, or a skeleton. The other type of fish is the cartilaginous fish which do not have a skeleton but has cartilage part making up its support system.
Due to the fact that coral reefs are so much different than the rest of the ocean, coral reef fish have developed adaptations to better suit them for that environment that fish living elsewhere in the ocean do not have. The most obvious is the coloration of the reef fish verse open ocean fish which tend to be monochromatic or slivery. The coloration of the reef fish is to aid in mating, or serve as a warning for fish that are venomous. Fish in the open ocean tend to be torpedo shaped to be more hydrodynamic so that they can swim faster. Reef fish are built more for maneuverability than speed and tend to have tall flat bodies. Finally, the way reef fish eat and digest their food is highly specialized for the type of prey they consume. A great example is the parrot fish which has adapted a beak like structure perfect for scraping algae off of the coral. [16]
The parrotfish belong to the kingdom Animalia, the phylum Chordata, the Class Actinopterygii, the order Perciformes, the family Labridae, and the genus Scaridae. [9] The Scaridae or parrotfish are a very diverse group of reef fish, typically they are brightly colored as adults, while the juveniles are a dull brown color. The smallest parrotfish, the Green Parrotfish, gets as big as 20 centimeters, whereas the largest parrotfish, the Bumphead parrotfish, can reach a massive size of 1.5 meters. Larger species tend to live longer, consequently the Bumphead parrotfish can live up to 20 years, but most other species do not live longer than 5 years. [9] They get their common name from the beak like formation of jaws and teeth which they use in junction with a second set of teeth in their jaws to grind up their main food supply coral and algae. They grind up the algae and coral and excrete fine sand as a waste product. [7]
The parrotfish are unique in the fact that some of them have a diurnal sleep cycle, which means they sleep at night and are active during the day. At night they seek shelter on the reef and construct a mucous envelope around themselves to protect them from predation in their vulnerable state. Bumphead parrotfish are the best example of this mucous envelope. They shut down their metabolic processes at night to conserve energy.[9]
The parrot fish have a very unusual life cycle. There are three standard phases between them but not every species has all three. In the juvenile phase the individuals are sexually immature and are dull in color. Some species are born all female and some species have true male and female genders. In the second phase called the initial phase the individuals are sexually mature but the color does not differentiate between the two genders. In the last phase called the terminal phase only mature males exist with bright and vivid colors. This is the male that fertilizes all the females in his group. An initial phase male can pose as a female to get close to the mating pair and release gametes in hopes of fertilizing the female and passing along his own DNA. When the dominant male dies it is a cue for the females of the group change into the dominant male. [10] Spawning varies from species to species from several times a day to only at dusk. The spawning can follow the lunar cycle or high tide. [10]
Due to the fact that coral reefs are so much different than the rest of the ocean, coral reef fish have developed adaptations to better suit them for that environment that fish living elsewhere in the ocean do not have. The most obvious is the coloration of the reef fish verse open ocean fish which tend to be monochromatic or slivery. The coloration of the reef fish is to aid in mating, or serve as a warning for fish that are venomous. Fish in the open ocean tend to be torpedo shaped to be more hydrodynamic so that they can swim faster. Reef fish are built more for maneuverability than speed and tend to have tall flat bodies. Finally, the way reef fish eat and digest their food is highly specialized for the type of prey they consume. A great example is the parrot fish which has adapted a beak like structure perfect for scraping algae off of the coral. [16]
The parrotfish belong to the kingdom Animalia, the phylum Chordata, the Class Actinopterygii, the order Perciformes, the family Labridae, and the genus Scaridae. [9] The Scaridae or parrotfish are a very diverse group of reef fish, typically they are brightly colored as adults, while the juveniles are a dull brown color. The smallest parrotfish, the Green Parrotfish, gets as big as 20 centimeters, whereas the largest parrotfish, the Bumphead parrotfish, can reach a massive size of 1.5 meters. Larger species tend to live longer, consequently the Bumphead parrotfish can live up to 20 years, but most other species do not live longer than 5 years. [9] They get their common name from the beak like formation of jaws and teeth which they use in junction with a second set of teeth in their jaws to grind up their main food supply coral and algae. They grind up the algae and coral and excrete fine sand as a waste product. [7]
The parrotfish are unique in the fact that some of them have a diurnal sleep cycle, which means they sleep at night and are active during the day. At night they seek shelter on the reef and construct a mucous envelope around themselves to protect them from predation in their vulnerable state. Bumphead parrotfish are the best example of this mucous envelope. They shut down their metabolic processes at night to conserve energy.[9]
The parrot fish have a very unusual life cycle. There are three standard phases between them but not every species has all three. In the juvenile phase the individuals are sexually immature and are dull in color. Some species are born all female and some species have true male and female genders. In the second phase called the initial phase the individuals are sexually mature but the color does not differentiate between the two genders. In the last phase called the terminal phase only mature males exist with bright and vivid colors. This is the male that fertilizes all the females in his group. An initial phase male can pose as a female to get close to the mating pair and release gametes in hopes of fertilizing the female and passing along his own DNA. When the dominant male dies it is a cue for the females of the group change into the dominant male. [10] Spawning varies from species to species from several times a day to only at dusk. The spawning can follow the lunar cycle or high tide. [10]
Communities have been fishing coral reefs for thousands of years. The marine organisms were so abundant compared to the small individual human populations fishing them that marine conservation was never a thought until much more recent in history. A shorter fishing day was sufficient enough to catch enough fish to feed ones family and the lack of roads and refrigeration made trade of marine organisms difficult. Supply of marine organisms was seemingly limitless. [14]
Reef fisheries management was community based and was dependent on community beliefs. Community beliefs about the sea were very superstitious, believing that misfortune at sea was due to the discontentment of divine beings and spirits. Public apologies from fishermen or community sacrifices were used to appease these spirits if fish numbers were down. Colonial rule and world religion swept across these coastal fishing communities and challenged this approach to reef fisheries management. This indigenous approach to reef fisheries management still exists in many places around the world but now they have to function alongside state fisheries management which often do not acknowledge the beliefs of the indigenous people. [14]
The invention of stronger nylon fishing nets and lines, refrigerant technology and better transportation in combination with larger human population caused state involvement in coral reef fisheries management to become more active in the 1940s. In the 40s state involvement was geared toward exploitation of a resourced that still seemed limitless. This involved granting loans to fishermen to expand their fisheries and make them more efficient. This approach quickly ended in the 1950s with the increase of tourism to coral reef areas. This caused states to pay more attention to their reef coasts and they realized that conservation was necessary if tourism was to thrive in these areas. Marine parks were established after World War II, but it only took a few years for states to realize that these protected areas do not offer the promise of conservation they were hoped to. With corruption and poor understanding and relations with the fishing communities that existed protection of these areas have proven very difficult. [16]
There is very little history about this fish as a marine resource which could imply that it is a new resource. People could have turned to fishing this fish because the preferred carnivorous game reef fish such as Grouper and Snapper have been over fished. [5] They’re more abundant on the reef than these over fished populations are so people have resorted to eating them. Their diurnal sleep patterns make them more susceptible to humans. [8] The most popular way catching them is spearing them while they sleep. Hand line fishing is also used which is where a single line is bated with a hook and lure or multiple hooks and lures and is held in the hand instead of a fishing pole. [12] Another method is gill net fishing in which a net is suspended in the water with float to hold it up and weights to pull the bottom down. [13] The most popular uses for this fish is as food and as decoration in woven baskets. [10]
Reef fisheries management was community based and was dependent on community beliefs. Community beliefs about the sea were very superstitious, believing that misfortune at sea was due to the discontentment of divine beings and spirits. Public apologies from fishermen or community sacrifices were used to appease these spirits if fish numbers were down. Colonial rule and world religion swept across these coastal fishing communities and challenged this approach to reef fisheries management. This indigenous approach to reef fisheries management still exists in many places around the world but now they have to function alongside state fisheries management which often do not acknowledge the beliefs of the indigenous people. [14]
The invention of stronger nylon fishing nets and lines, refrigerant technology and better transportation in combination with larger human population caused state involvement in coral reef fisheries management to become more active in the 1940s. In the 40s state involvement was geared toward exploitation of a resourced that still seemed limitless. This involved granting loans to fishermen to expand their fisheries and make them more efficient. This approach quickly ended in the 1950s with the increase of tourism to coral reef areas. This caused states to pay more attention to their reef coasts and they realized that conservation was necessary if tourism was to thrive in these areas. Marine parks were established after World War II, but it only took a few years for states to realize that these protected areas do not offer the promise of conservation they were hoped to. With corruption and poor understanding and relations with the fishing communities that existed protection of these areas have proven very difficult. [16]
There is very little history about this fish as a marine resource which could imply that it is a new resource. People could have turned to fishing this fish because the preferred carnivorous game reef fish such as Grouper and Snapper have been over fished. [5] They’re more abundant on the reef than these over fished populations are so people have resorted to eating them. Their diurnal sleep patterns make them more susceptible to humans. [8] The most popular way catching them is spearing them while they sleep. Hand line fishing is also used which is where a single line is bated with a hook and lure or multiple hooks and lures and is held in the hand instead of a fishing pole. [12] Another method is gill net fishing in which a net is suspended in the water with float to hold it up and weights to pull the bottom down. [13] The most popular uses for this fish is as food and as decoration in woven baskets. [10]
www.flickr.com
Parrotfish are often the most abundant fish on the coral reefs. They are becoming a more popular fishery species as populations of carnivorous fish in the coral reefs decline. [4] For example the Nassau grouper, which is found in the same tropical waters as the parrotfish is IUCN redlist endangered. The justification for its status is that it has been estimated to have declined sixty percent over the last three generations or about thirty years. The Nassau grouper is both commercially and recreationally fished using a variety of fishing methods. The Nassau grouper is considered commercially extinct in many areas and the most popular way of catching large numbers of them is to target spawning aggregations. The United States has banned the fishing of this species in federal waters. [17] Another example that shares the parrotfish range is the Black grouper which is IUCN redlist near threated. They have declined thirty percent and they are expected to continue to decline if current conditions continue. The Black grouper inhabits many protected marine areas throughout its range and size limits have been placed in Brazil of 45 cm minimum to control the delineation of this species. [18]
The genus Scaridae has not been evaluated on the IUCN redlist. There is, right now, only one species evaluated and named as a vulnerable species and that is the Rainbow Parrotfish. [9] The Bumphead Parrotfish is currently considered a species of concern. [5] According to the scientific literature these fish are not in any immediate danger and therefore projections are difficult to find. The media feels differently with court cases demanding the protection of these reef fish as a way to save the coral reefs. The lawsuit claims that the National Marine Fisheries Service violated the endangered species act by finding that the unregulated fishing of parrotfish did not pose a threat the livelihood of the corals. They claim that Elkhorn and Stagehorn corals, which are endangered, need the parrotfish to survive because they clear the algal and bacterial growth on them which could choke them out. [3]
This is an example of why there needs to be an international effort to conserving and protecting our resources. There are numbers for the species on the coast of United States territories but none for non-United States territories. Different countries will not cooperate together to gather data for the whole genus. How can we form an opinion if the powers that be do not have one, and more importantly cannot get one? As of right now they do not seem to be very concerned about these fish because they are not a big fishery yet. That will change when the Snapper, Grouper, and other carnivorous fish populations dwindle until they cannot support the demands of being an important marine resource to commercial fisheries. When this happens Parrotfish, and other herbivorous reef fish, will become more popular.
The genus Scaridae has not been evaluated on the IUCN redlist. There is, right now, only one species evaluated and named as a vulnerable species and that is the Rainbow Parrotfish. [9] The Bumphead Parrotfish is currently considered a species of concern. [5] According to the scientific literature these fish are not in any immediate danger and therefore projections are difficult to find. The media feels differently with court cases demanding the protection of these reef fish as a way to save the coral reefs. The lawsuit claims that the National Marine Fisheries Service violated the endangered species act by finding that the unregulated fishing of parrotfish did not pose a threat the livelihood of the corals. They claim that Elkhorn and Stagehorn corals, which are endangered, need the parrotfish to survive because they clear the algal and bacterial growth on them which could choke them out. [3]
This is an example of why there needs to be an international effort to conserving and protecting our resources. There are numbers for the species on the coast of United States territories but none for non-United States territories. Different countries will not cooperate together to gather data for the whole genus. How can we form an opinion if the powers that be do not have one, and more importantly cannot get one? As of right now they do not seem to be very concerned about these fish because they are not a big fishery yet. That will change when the Snapper, Grouper, and other carnivorous fish populations dwindle until they cannot support the demands of being an important marine resource to commercial fisheries. When this happens Parrotfish, and other herbivorous reef fish, will become more popular.
http://www.hogarutil.com/mascotas/otras/peces/200902/loro-scaridae-6488.html
This genus is currently IUCN redlist unevaluated; since this genus has not been evaluated there are no scientific forecasts for their future. According to scientific data currently it seems that environmental factors are the biggest threats to the well-being of parrotfish. Parrotfish live off coral mostly so the destruction of the coral reefs and coral bleaching are concerns. Coral bleaching is caused by the death of the bacteria that the coral live with in a symbiotic relationship. This is thought to be caused by global warming. If the coral is dead then they won’t serve as a food source for these fish.
The destruction of the nursery habitats in the mangroves is another concern that could affect the future abundance and success of the Parrotfish. Pollution, human expansion and human consumption of resources in and near the mangroves, could affect the nursery habitats of these reef fish. As their nursery habitats become destroyed they will not have fewer and fewer places to reproduce, thus their subsequent generations will continue to dwindle. [19]
As more traditional game fish resources, such as the grouper, are exhausted the Parrotfish may become more susceptible to overfishing. The fact that they have a diurnal sleep pattern makes them more vulnerable to night spearfishing than other species. According to IUCN these reef fish are not in any danger, and no data is available for them outside the United States. I feel that as the over-fishing of the carnivorous fish continues the commercial fishing of parrotfish will increase in popularity causing the populations of these reef fish to decrease and become endangered. Currently the fishing of parrotfish in the United States Caribbean is greater than their reproductive rate, which means that eventually we will run out of parrotfish to catch in these areas. [4]
The only parrotfish to be declared near threatened on the IUCN redlist is the Rainbow parrotfish. They were declared near threatened in 1996. Their population trend is going downward. They are locally extinct in many areas that they once flourished. This seems to be due mostly to the destruction of the mangrove habitats which they use as their nursery habitats due to human use and consumption of resources there. I feel that if the current conditions continue that many more species of parrotfish will face the same fate. [19]
Without the parrotfish the coral reefs will suffer tremendously. They are considered the gardeners of the coral reefs and the bigger parrotfish cannot be replaced by the smaller fish that also groom the reef. They help clear the over growth of algae and bacteria which can suffocate the coral and the species living on them. They also remove debris that can damage the corals. It is estimated that parrotfish produce 200 lbs. of sand a year for the beaches that attract so many tourist in the Caribbean. [4]
The destruction of the nursery habitats in the mangroves is another concern that could affect the future abundance and success of the Parrotfish. Pollution, human expansion and human consumption of resources in and near the mangroves, could affect the nursery habitats of these reef fish. As their nursery habitats become destroyed they will not have fewer and fewer places to reproduce, thus their subsequent generations will continue to dwindle. [19]
As more traditional game fish resources, such as the grouper, are exhausted the Parrotfish may become more susceptible to overfishing. The fact that they have a diurnal sleep pattern makes them more vulnerable to night spearfishing than other species. According to IUCN these reef fish are not in any danger, and no data is available for them outside the United States. I feel that as the over-fishing of the carnivorous fish continues the commercial fishing of parrotfish will increase in popularity causing the populations of these reef fish to decrease and become endangered. Currently the fishing of parrotfish in the United States Caribbean is greater than their reproductive rate, which means that eventually we will run out of parrotfish to catch in these areas. [4]
The only parrotfish to be declared near threatened on the IUCN redlist is the Rainbow parrotfish. They were declared near threatened in 1996. Their population trend is going downward. They are locally extinct in many areas that they once flourished. This seems to be due mostly to the destruction of the mangrove habitats which they use as their nursery habitats due to human use and consumption of resources there. I feel that if the current conditions continue that many more species of parrotfish will face the same fate. [19]
Without the parrotfish the coral reefs will suffer tremendously. They are considered the gardeners of the coral reefs and the bigger parrotfish cannot be replaced by the smaller fish that also groom the reef. They help clear the over growth of algae and bacteria which can suffocate the coral and the species living on them. They also remove debris that can damage the corals. It is estimated that parrotfish produce 200 lbs. of sand a year for the beaches that attract so many tourist in the Caribbean. [4]
1. Brainy Quote
http://www.brainyquote.com/quotes/keywords/resource.html
2. Cosmos the Science of Everything
http://www.cosmosmagazine.com/news/decrease-parrotfish-a-danger-reefs/
3. Earth Justice
http://earthjustice.org/news/press/2012/lawsuit-aims-to-protect-endangered-caribbean-corals-from-overfishing
4. The PEW Environment Group
http://www.pewenvironment.org/uploadedFiles/PEG/Publications/Fact_Sheet/PewCaribbean040611.pdf
5. IUCN Redlist
http://www.iucnredlist.org/details/63571/0
6. National Oceanic and Atmospheric Administration
http://www.nmfs.noaa.gov/pr/pdfs/species/bumpheadparrotfish_highlights.pdf
7. Arkive
http://www.arkive.org/humphead-parrotfish/bolbometopon-muricatum/
8. National Oceanic and Atmospheric Administration
http://www.fpir.noaa.gov/PRD/prd_bumpheadparrotfish.html
9. Animal Diversity Web
http://animaldiversity.ummz.umich.edu/accounts/Scaridae/
10. Sheppardsoftware
http://www.sheppardsoftware.com/content/animals/animals/fish/parrotfish.htm
11. Wikipedia
http://en.wikipedia.org/wiki/Handline_fishing
12. The Oregon Encyclopedia
http://www.oregonencyclopedia.org/entry/view/gillnet_fishing/
13. Smithsonian Tropical Research Instiute
http://www.stri.si.edu/sites/publications/PDFs/STRI-W_DeBrot_et_al_2007.pd
14. Encyclopedia of Earth
http://www.eoearth.org/article/Managing_coral_reef_fisheries
15. Field Museum of Natural History
ftp://ftp.fao.org/docrep/fao/009/y4162e/y4162e42.pdf
16. Coral-Reef Info
http://www.coral-reef-info.com/coral-reef-fishes.html
17. IUCN Redlist
http://www.iucnredlist.org/details/7862/0
18. IUCN Redlist
http://www.iucnredlist.org/details/132724/0
19. IUCN Redlist
http://www.iucnredlist.org/details/19950/0
http://www.brainyquote.com/quotes/keywords/resource.html
2. Cosmos the Science of Everything
http://www.cosmosmagazine.com/news/decrease-parrotfish-a-danger-reefs/
3. Earth Justice
http://earthjustice.org/news/press/2012/lawsuit-aims-to-protect-endangered-caribbean-corals-from-overfishing
4. The PEW Environment Group
http://www.pewenvironment.org/uploadedFiles/PEG/Publications/Fact_Sheet/PewCaribbean040611.pdf
5. IUCN Redlist
http://www.iucnredlist.org/details/63571/0
6. National Oceanic and Atmospheric Administration
http://www.nmfs.noaa.gov/pr/pdfs/species/bumpheadparrotfish_highlights.pdf
7. Arkive
http://www.arkive.org/humphead-parrotfish/bolbometopon-muricatum/
8. National Oceanic and Atmospheric Administration
http://www.fpir.noaa.gov/PRD/prd_bumpheadparrotfish.html
9. Animal Diversity Web
http://animaldiversity.ummz.umich.edu/accounts/Scaridae/
10. Sheppardsoftware
http://www.sheppardsoftware.com/content/animals/animals/fish/parrotfish.htm
11. Wikipedia
http://en.wikipedia.org/wiki/Handline_fishing
12. The Oregon Encyclopedia
http://www.oregonencyclopedia.org/entry/view/gillnet_fishing/
13. Smithsonian Tropical Research Instiute
http://www.stri.si.edu/sites/publications/PDFs/STRI-W_DeBrot_et_al_2007.pd
14. Encyclopedia of Earth
http://www.eoearth.org/article/Managing_coral_reef_fisheries
15. Field Museum of Natural History
ftp://ftp.fao.org/docrep/fao/009/y4162e/y4162e42.pdf
16. Coral-Reef Info
http://www.coral-reef-info.com/coral-reef-fishes.html
17. IUCN Redlist
http://www.iucnredlist.org/details/7862/0
18. IUCN Redlist
http://www.iucnredlist.org/details/132724/0
19. IUCN Redlist
http://www.iucnredlist.org/details/19950/0