SPECIES OF CLOWNFISH AND ANEMONEFISH
Scientists recognize 29 species of clownfish and anemonefish living in tropical and subtropical waters in Indian and western Pacific oceans. They live among the reefs from East Africa to French Polynesia and from Japan to eastern Australia, with the greatest concentration of diversity on the north coast of New Guinea in the Bismarck Sea (where with a little luck and a competent guide you can see seven species on one reef).
On a diving trip to Fiji, Gerald Allen — a research associate at the Western Australian Museum and the one the world's foremost clownfish authority — discovered the 29th species, Amphiprion barberi. That brought his lifetime total to seven clownfish (and nearly 500 species of reef fish). "I still get a huge buzz when I find something new," Allen says. "Amphiprion barberi is a beautiful clown, orange and red like a blazing ember on the reef."
Some species of clownfish are specific to a certain area. One species, for example, is found only in waters off the Maldives and Sri Lanka. Another is found only around the Seychelles Islands. Clark’s anemonefish is the most widespread. It is found in the Persian Gulf, across the India Ocean and Southeast Asia and as far north as India and as far south as Australia.
Websites and Resources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Fishbase fishbase.se ; Encyclopedia of Life eol.org ; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; Woods Hole Oceanographic Institute whoi.edu ; Cousteau Society cousteau.org ; Monterey Bay Aquarium montereybayaquarium.org ; MarineBio marinebio.org/oceans/creatures
Different Clownfish and Anemonefish Species
Clownfish and anemonefish are members of the colorful damselfish family (Pomacentridae). Amphiprion is a genus of ray-finned fish which comprises all but one of the clownfish or anemonefish species with the the subfamily Amphiprioninae of the family Pomacentridae. One is in the genus Premnas — the maroon clownfish. ,
The following species are classified in the genus Amphiprion:
1) Amphiprion polymnus (Linnaeus, 1758) (Saddleback clownfish)
2) Amphiprion ephippium (Bloch, 1790) (Saddle anemonefish)
3) Amphiprion percula (Lacepède, 1802) (Orange clownfish)
4) Amphiprion bicinctus Rüppell, 1830 (Twoband anemonefish)
5) Amphiprion chrysogaster Cuvier, 1830 (Mauritian anemonefish)
6) Amphiprion chrysopterus Cuvier, 1830 (Orangefin anemonefish)
7) Amphiprion clarkii (J. W. Bennett, 1830) (Yellowtail clownfish)
8) Amphiprion ocellaris Cuvier, 1830 (Clown anemonefish)
9) Amphiprion rubrocinctus Richardson, 1842 (Red Anemonefish)
10) Amphiprion melanopus Bleeker, 1852 (Fire clownfish)
11) Amphiprion akallopisos Bleeker, 1853 (Skunk clownfish)
12) Amphiprion sebae Bleeker, 1853 (Sebae anemonefish)
13) Amphiprion perideraion Bleeker, 1855 (Pink anemonefish)
14) Amphiprion frenatus Brevoort, 1856 (Tomato clownfish)
15) Amphiprion latezonatus Waite, 1900 (Wide-band Anemonefish)
16) Amphiprion nigripes Regan, 1908 (Maldive anemonefish)
17) Amphiprion mccullochi Whitley, 1929 (Whitesnout anemonefish)
18) Amphiprion tricinctus Schultz & Welander, 1953 (Three-band anemonefish)
19) Amphiprion allardi Klausewitz, 1970 (Twobar anemonefish)
20) Amphiprion chagosensis Allen, 1972 (Chagos anemonefish)
21) Amphiprion fuscocaudatus Allen, 1972 (Seychelles anemonefish)
22) Amphiprion latifasciatus Allen, 1972 (Madagascar anemonefish)
23) Amphiprion akindynos Allen, 1972 (Barrier reef anemonefish)
24) Amphiprion sandaracinos Allen, 1972 (Yellow clownfish)
25) Amphiprion leucokranos Allen, 1973 (Whitebonnet anemonefish)
26) Amphiprion thiellei Burgess, 1981 (Thielle's anemonefish)
27) Amphiprion omanensis Allen & Mee, 1991 (Oman anemonefish)
28) Amphiprion barberi Allen, Drew & Kaufman, 2008
29) Amphiprion pacificus Allen, Drew & Fenner, 2010 (Pacific anemonefish) [Source: Wikipedia]
Common clownfish (Scientific name: Amphiprion ocellaris) are also known as the clown anemonefish and false clown anemonefish. The most common type of clownfish found in aquariums, it may live in the wild six to ten years although its lifespan has not been studied there. [Source: Dani Newcomb, Animal Diversity Web (ADW) /=]
Common clownfish live in tropical, saltwater and are native to Asia, the Pacific Ocean and Australia. Its range includes Northwest Australia, Southeast Asia, and as far north as the Ryukyu Islands of Japan The fish tends inhabit coral reefs and sheltered lagoons at depths of 15 to one meter (49.21 to 3.28 feet). It is mainly found in or near the sea anemones Heteractis magnifica, Stichodactyla gigantean, and Stichodactyla mertensii and they have a symbiotic relationship with these anemones.
In the larval stage, the fish is extremely susceptible to predation as they have no way of defending themselves and have high mortality rates. They are popular aquarium fish,
Common Clownfish Characteristics and Behavior
Common clownfish range in lengths up to 110 millimeters (4.33 inches), with their average length being 80 millimeters (3.15 inches). Females are larger than males. According to Animal Diversity Web: Common clownfish are orange to reddish-brown with three white bands on the head and body. The white bands are outlined in black. Black Common clownfish, with white bands and black coloring instead of orange, are found off the Northern Territory of Australia. Common clownfish has a rounded caudal fin and may grow up to 110 millimeters in length. There are 11 dorsal spines and 17 pectoral rays that help to distinguish it from the closely related Amphiprion percula. Females are larger than males in this species. [Source: Dani Newcomb, Animal Diversity Web (ADW) /=]
Common clownfish exists in a symbiotic relationship with the Heteractis magnifica, Stichodactyla gigantean, and Stichodactyla mertensii sea anemones. They are dependent on the anemones for protection. In open waters these fish are susceptible to attacks predators and are poor swimmers. In addition, anemones provide protection for the nests. The anemones are observed to generally do better with a host fish and may also benefit possibly from fish consumption of parasites and increased water circulation from fanning.
As the juveniles search for an anemone, their survival is contingent upon finding an anemone to reside in, but this process is complicated by the dynamics within the anemone. Because of the hierarchical dynamics within the anemone, the new juvenile fish enters the system at the bottom and is exposed to the worst aggression and may be driven away. Common clownfish are able to find one of the three species of sea anemones by olfactory clues, due to imprinting that occurred while in the nest /=\
Common clownfish communicate with vision and touch and sense using vision, touch and chemicals usually detected with smell. Communication during mating occurs through the male biting, chasing, and extending his fins towards the female. The hierarchical system is communicated through aggression by the larger members residing in the anemone at the smaller individuals. The fish is able to find host anemones by olfactory imprinting that occurs while in the nest. /=\
Common Clownfish Sexuality, Mating and Reproduction
common clownfish ((Amphiprion ocellaris) at Great Barrier Reef Common clownfish are monogamous.As is the case with other members of the subfamily Amphiprioninae, or anemonefishes, they are protandrous hermaphrodites, meaning that all individuals develop first into males and then possibly into females later. According to Animal Diversity Web: An adult male and female and several juveniles may reside together in an anemone. If the female were to be removed or die, the largest male would then become the female, with the larger of the immature fish transforming into a male. Females control males with aggressive dominance, thus controlling the creation of other females The largest male will in turn dominate the juveniles and prevents other males from spawning. [Source: Dani Newcomb, Animal Diversity Web (ADW) /=]
Common clownfish are able to breed nearly year round because it inhabits tropical waters but may be somewhat limited in the northern reaches of its distribution during winter months. Spawning is concentrated around the full moon and usually occurs in the morning. Possible reasons for this include: stronger water currents for larval distribution, greater food supplies due to invertebrate spawning at the same time, and overall increased visibility. /=\
When spawning is about to occur, the male will chase the female to the nest, but the female actually begins the process. The female makes several passes over the nest and eventually lays orange eggs over the period of 1-2 hours before leaving the nest. Eggs are approximately 3-4 millimeters in length and range in number from 100-1000 depending on the age of the fish. The male then continues the process as he passes over the eggs, fertilizing them. Eggs are attached to the substrate with a fine thread. Incubation is affected by water temperature, the cooler the water, the longer incubation period, but in general it requires 6-8 days before hatching occurs. The planktonic larval stage lasts from 8-12 days and ends when the juvenile fish settle returns to the bottom and attempt to find an anemone to inhabit. /=\
Common Clownfish Predators, Conservation and Humans
In its relationship with the three anemone species. the common clownfish receives protection from the anemone in the form of daily shelter and for its nest. According to Animal Diversity Web: The anemone receives protection too, as it has been documented that in the absence of a guest fish, the anemones may be attacked by butterfly fish or even turtles. Additionally, in the presence of the fish, bulbs are found on the end of tentacles that are believed to increase surface area available to solar energy The bulbs are not present in the absence of the fish. [Source: Dani Newcomb, Animal Diversity Web (ADW) /=]
Humans utilize common clownfish for the pet trade, research and education. They are part of the tropical fish aquarium trade and certain rare colors of the species are specifically sought. They are easily bred in captivity and may be used in research. The high demand for the Common clownfish in the aquarium trade has reduced the population size in some locations, leaving the local populations open to over-exploitation and other threats.
The common clownfish species is not classified as threatened or Endangered. Captivity transfer experiments have been performed to address the possibility of restocking the fish in areas where they have been depleted; these find that survival among transferred fish is higher among smaller common clownfish
Maroon clownfish (scientific name: Premnas biaculeatus) are also known as spinedcheek anemonefish. Their lifespan in captivity is typically three to five years under good conditions but has has not been well researched in the wild., where they tend live longer — from six to 10 years. A related species, pink anemonefish (Amphiprion perideraion), was recorded living to 18 years..[Source: Johanna Higuera, Animal Diversity Web (ADW) /=]
Also popular aquarium fish, maroon clownfish are native to the Pacific Ocean and Indian Ocean. They live in tropical, saltwater and you can typically find them in reefs or other coastal areas at depths of up to 50 meters (164 feet) because their anemones require sunlight to grow. Maroon clownfish have been spotted off coasts of Thailand, Malaysia, Indonesia, Philippines, Burma, India, New Guinea, New Britain, Solomon Islands, Vanuatu and northern Queensland. /=\
The maroon clownfish the only member of the clownfish and anemonefish group that belongs to the genus Premnas. Historically, anemonefish have been identified by morphological features and color pattern in the field and features such as scalation of the head, tooth shape, and body proportions in the laboratory. The spine on the cheek of the fish is the characteristic that distinguishes the genus Premnas from the closely related Amphiprion. Maroon clownfish were been thought to have a monospecific lineage, however genetic analysis has shown they closely related to other clownfish and anemonefish.
Life of the Maroon Clownfish
The Entacmaea quadricolor, bulb-tentacle sea anemones, is the only host species for maroon clownfish. According to Animal Diversity Web: This anemone species is characterized by polyps 50 to 400 millimeters in diameter, depending on depth. They have brown tentacles of about 100 millimeters long with a red tip and white bulb at the end of the tentacle. Maroon clownfish benefit their sea anemone hosts by protecting them from butterflyfish, which would otherwise eat their tentacles. Maroon clownfish also clean away debris and parasites from the anemone.
Maroon clownfish tend to live mainly in solitary sea anemone specimens on reef slopes fairly close to the ocean surface. The mutualistic zooxanthellae (living within the anemone) need sunlight to photosynthesize and provide energy for themselves and the anemone. These anemone prefer tropical warm waters with the temperature ranging between 25 and 28°C (77-82°F). They feed mainly on copepods and planktonic, larval tunicates. They also eat other kinds of plankton and algae. /=\
Their main known predators are wrasses. According to Animal Diversity Web: The most vulnerable stage for maroon clownfish is during the egg and larval stage, when they are not protected by a host anemone and float freely in the water column. As settled adults, Entacmaea quadricolor protects these symbiotic fish because of their ability to deliver a venomous sting. Wrasses are known to prey on eggs and other fish are likely predators of eggs, larvae, and unsettled juveniles.
Humans utilize maroon clownfish in the pet trade, ecotourism, research and education. They are an important source of income for aquarium suppliers and ecotourist draws for diving operations. Although maroon clownfish are not Endangered, there are concerns for populations and their reef habitats due to the "Nemo craze". Collecting methods are often extremely destructive, permanently damaging reefs.
Maroon Clownfish Characteristics and Behavior
Maroon clownfish range in length from less than 60 millimeters (2.36 inches) to 160 millimeters (6.30 inches), with their average length being 70 millimeters (2.76 inches). They are among the easiest anemonefish to identify, even when young. They are bright red with three bars that are bright white in males and grey in females. Individuals may become bright white if they are provoked. The lines may also be bright yellow.[Source: Johanna Higuera, Animal Diversity Web (ADW) /=]
Maroon clownfish are diurnal (active mainly during the daytime), sedentary (remain in the same area), territorial (defend an area within the home range) and have dominance hierarchies (ranking systems or pecking orders among members of a long-term social group, where dominance status affects access to resources or mates). They communicate with vision, touch and chemicals usually detected with smell. /=\
Once they settle onto an anemone as a juvenile, and then adult, maroon clownfish remain in the same area throughout their life. They defend the area around their host anemone. According to Animal Diversity Web: Maroon clownfish have a social hierarchy in which fish that occupy the same patch of anemones are ordered in status by size. Generally there is a breeding pair and then zero to 4 non-breeders. The largest is the female of the group (highest rank), followed by the largest male, who is part of the breeding pair. In the case of the death of the female, the second largest changes from male to female. Size difference is maintained in order to avoid subordinates becoming a threat to the highest ranking male. There is an average difference of 10 millimeters between ranks in the related anemonefish, Amphiprion percula. When a dominant anemonefish dies, the next subordinate moves up in the rank order and grows further. /=\
Maroon Clownfish Mating, Reproduction, and Development
Maroon clownfish are monogamous and mated pairs may stay together for several years. Reproduction is external, meaning the male’s sperm fertilizes the female’s egg outside her body. They are also sequential hermaphrodites in which individuals change their sex at some point in their lives and typically produces eggs and sperm at different stages their lives. In the case of maroon clownfish, males may be half the size of females and their gonads have dormant ovarian cells as well as functioning testes. [Source: Johanna Higuera, Animal Diversity Web (ADW) /=]
In the tropics spawning occurs year-round; those in temperate and subtropical waters spawn when the temperatures are highest in summer and spring. The number of offspring ranges from 100 to 1000. The time to hatching ranges from six to seven days and the age in which they become independent ranging from eight to 12 days.
According to Animal Diversity Web: The dominant female is the largest and has one partner, which is the next largest male within a cluster of anemones. The growth of other anemonefish in the same anemone patch is stunted by the presence of a dominant male and female, keeping them smaller than the dominant male. When one or the other of the dominant individuals dies, subordinates grow and replace the dead individual. For example, if the dominant male dies, the next largest male will replace him and continue to grow to its maximum size. /=\
Before spawning, males go through an extensive ritual of courtship that consists of displaying the dorsal, anal and pelvic fins. He also chases and nips his mate. Mates communicate in courtship through movement and touch. During spawning, females swim in a zig-zag pattern over the nest while the male fertilizes the eggs. Males also “shows off” their fins to females, a form of visual communication. /=\
During the pre-fertilization stage provisioning and protecting is done by females. Pre-birth protection is provided by the male, meaning that males care primarily for the eggs. Before spawning, males find and prepare a nest for the eggs. He cleans the area by removing the debris and algae from the area. Usually the female ends up joining in the task. During incubation the male guards and cares for the nest. He chases away any possible predators that may want to feast on the eggs, such as wrasses.
The developmental stages of maroon clownfish are egg, larvae, young and adult. The transparent, elliptical eggs are 3-4 millimeters in size. Anemonefish hatch with advanced alimentary canals and feed on the yolk, which usually lasts for about three days. Five days after hatching they develop supranuclear inclusions around the hindgut, which suggests pinocytotic digestion of protein. Between three to five days after hatching is the period of highest mortality stage for anemonefish if they cannot find food. It is also the time when they transition from endogenous to exogenous feeding. Seven days after hatching they attain gastric glands and by the 9th day they have supranuclear vacuoles that indicate exogenous digestive capabilities. Maroon clownfish hatch six to seven days after fertilization, and then undergo a seven to 14 day pelagic (living in the open ocean, far from land) larval stage. After fertilization, they complete the development of the olfactory organ in 19 days, retinal differentiation in 20 days and skeletal ossification in about 22 days.
Metamorphosis occurs when anemonefish leave surface waters and swim to the sea bottom. It then takes on the color pattern of a juvenile. This process usually takes about one day. This marks the beginning of the settlement period, in which individuals seek out an uninhabited anemone host. Maroon clownfish develop more rapidly than other anemonefish species. Their eyes develop especially rapidly. Vision is directly correlated with the ability to attain food because most larval fish are visual feeders. Olfactory cues are used to detect host anemones. During the larval stage maroon clownfish live on the water surface where they are transported by currents.
Tomato clownfish (Scientific name: Amphiprion frenatus) are also known as blackback anemonefish, fire clown, onebar anemonefish and red clown. Their average lifespan in the wild is estimated to be six to 10 years. One specimen lived 18 years in captivity. Though more is known about this species than other anemonefishes, the knowledge surrounding its longetivity in the wild is limited. It is possible to make a general guess at their age based on the the stripes on their bodies. When young, these fish will have more white stripes on their hind regions. However, not all individuals lose the juvenile pattern as they mature. [Source: Kristen Leutheuser, Animal Diversity Web (ADW) /=]
Tomato clownfish are native to the Pacific Ocean and Asia. They live in tropical seas in reefs and are typically found at depths of one to 12 meters (3.28 to 39.37 feet). They are known to inhabit lagoon reefs, particularly with embayments, and are primarily found in the Western Pacific in the South China Sea and off of Indonesia, Singapore, Malaysia, Thailand, Vietnam, China, Philippines, and Taiwan. They have been found in waters as far north as the Ryukyu Islands and the southern parts of Japan. /=\
Tomato clownfish have a symbiotic relationship with the the bulb-tentacle sea anemone (Entacmaea quadricolor) Although they can both live without each other, their health and rate of survival are increased when tomato clownfish live within the anemones tentacles. Tomato clownfish eat algae, zooplankton, and small, aquatic crustaceans. When a tomato clownfish brings food back to an anemone, the anemone is rewarded with crumbs from the meal. Humans utilize them for the pet trade. This species is not listed on any of the Endangered or threatened lists.
Tomato Clownfish Characteristics and Behavior
Tomato clownfish can grow up to 14 centimeters (5.5 inches) in length. Females are larger than males. Both males and females have a distinct orange body, which may turn black in older individuals. Behind the head of the fish, a black-edged bar extends from the top of the head towards the belly. A second black-edged white bar may be found around the mid-section of the body. Tomato clownfish have 9-10 dorsal-fin spines and 16-18 dorsal soft rays. The fish species also has two anal-fin spines and 13-15 anal soft rays. [Source: Kristen Leutheuser, Animal Diversity Web (ADW) /=]
Tomato clownfish have dominance hierarchies (ranking systems or pecking orders among members of a long-term social group, where dominance status affects access to resources or mates). According to Animal Diversity Web: They have a complex social hierarchy that rules not only who is in charge of the host anemone, but also the size of the other fish that live within it. At the bottom of the hierarchy are the juvenilles. Usually several juveniles will share one anemone with a mating pair. A sexually mature male is next in line in the hierarchy, with the female at the top. All Tomato clownfish are born as males, and will only change into a female when the female of the host anemone has left. /=\
The female initiates a non-threatening, harassing behavior towards the mature male with whom she shares the anemone. From this behavior, the male in turn harasses the juveniles in the same manner. Since the juveniles are constantly being chased by the male and sometimes the female, they seldom have time to eat enough nutrients to grow any larger. This behavior inhibits the growth of the newer fish to the anemone. Even the male is half as large as the female due to her consistant harassment of him. Therefore, when the female is absent from the anemone, both the male and the juveniles experience a large growth spurt. /=\
Tomato clownfish are also territorial (defend an area within the home range), The territory size depends upon the size of the fish. The smallest tomato clownfish will usually stay very close to the host anemone when foraging for food due to their increased risk of predation. Larger anemonefishes that are at the top of the social heirarchy in the host anemone will travel many meters from their host. Not much is known about the communication of tomato clownfish, except that when they are either defending themselves or attacking others, they will make a "tack-tack" sound. They communicate with sound and sense using vision, touch and chemicals usually detected with smell.
Tomato Clownfish Reproduction and Development
Tomato clownfish usually mate for life. However, if one partner leaves, then the other will find a replacement for its lost mate. According to Animal Diversity Web: When courting a female, a male will exhibit both sterotyped and ritualised behavior. A male will chase a female, as he becomes more bold. He also has the tendancy to show off for his mate by erecting his dorsal, anal, and pelvic fins as he remains in one spot near her, much like a statue. Another form of behavior recorded among Tomato clownfish is "signal jumping," which means that a male will move rapidly around an anemone in an up and down manner. In the beginning of their courtship, a male will also spend a large amount of time picking out the nesting site that he will eventually guard if he is successful in mating with a female. At the end of courtship, she will also help her mate in clearing the nesting site of algae and other debris. When laying eggs, a female will place the adhesive eggs on a rock near the anemone. The male then watches over them until they hatch. /=\
Tomato clownfish are protandrous (the condition of hermaphrodites that have male organs and sperm before female organs and eggs) and are sequential hermaphrodites in which individuals change their sex at some point in their lives and typically produces eggs and sperm at different stages their lives. Like all Amphiprion, breed all year long in the tropics, but only in the warmer months of temperate locations. Spawning occurs during a full moon, which is characteristic of all anemome fishes. The number of offspring ranges from 100 to more than 1,000. The average time to hatching is 6-7 days, with independence occurring on average at 8-12 days. After the eggs are laid near the host anemone, the male looks after the eggs, and both the male and female will protect the eggs as well. After the larvae hatch, they swim away to find an anemone of their own to inhabit, and no further care is given by the parents.
Beginning as an egg, tomato clownfish will take about one week to hatch and become larvae. After hatching, larvae will drift for about 16 days in plankton-rich waters. At the end of this drifting journey, the larvae will look for anemones of their own to inhabit. Their development from there depends upon social roles. A juvenile will only develop into a sexually mature male if this role in the anemone is not already filled. When the female of the anemone is absent, the largest mature male will then change into the sexually mature female. /=\
Orange clownfish (Scientific name: Amphiprion percula) is also known as True clown anemonefishes and blackfinned anemone fish. Their lifespan in the wild is typically six to 10 years. [Source: Jeff Lee, Animal Diversity Web (ADW) /=]
Orange clownfish are native only to the Indo-Pacific Region and found mostly around the western South Pacific and Australia, ranging from Northern Queensland to Melanesia (New Guinea, New Britain, New Ireland, the Solomon Islands, and Vanuatu).
Because of it close relationship with its tree sea anemone hosts, the distribution of the orange clownfish is determined by habitat of these hosts — the sea anemone species 1) Heteractis magnifica, 2) Stichodactyla gigantean, and 3) Stichodactyla mertensii. The clownfish and the clownfish typically reside in shallow coastal waters at at depths of one to 12 meters (3.28 to 39.37 feet) and water temperature ranges from 25-28 degrees C.. The distribution of sea anemones themselves is limited by the photosynthetic activity of golden-brown algae that occupy the anemones’ tentacles. The fish and anemone pair generally occurs on coral reefs.
Orange Clownfish Characteristics and Behavior
Orange clownfish can reach lengths of 110 millimeters (4.33 inches) and is often distinguished by three white vertical bars on a bright orange body. Females are larger than males. According to Animal Diversity Web: The anterior white bar occurs just behind the eye; the middle bar bisects the fish; the posterior bar occurs near the caudal fin. An anterior projecting bulge further characterizes the middle bar. In addition to the white coloring, black edging outlines each fin with varying thickness. Although Orange clownfish’s vibrant colors are eye catching, it is easily confused with the common clownfish (Amphiprion ocellaris, false clown anemonefish). One may distinguish the two by counting the number of dorsal-fin spines. Orange clownfish usually has 10 dorsal-fin spines, while A. ocellaris usually has 11. Also, the latter never has thick black margins outlining the fins. [Source: Jeff Lee, Animal Diversity Web (ADW) /=]
There is no difference in color patterns among sexes. Nonetheless, dimorphic variation is present, since the female is larger than the male. Polymorphism, although present in other species of anemonefishes, does not occur in Orange clownfish. Such is the case with melanistic (black pigmentation) variation in some anemonefish species. This is generally absent in Orange clownfish.
Habitation of a chosen anemone generally requires a period of acclimation. The protective mucous of orange clownfish is developed with repeated interactions with the host anemone. During its first encounter with the sea anemone, Orange clownfish will engage in a swimming dance, gingerly touching tentacles first to its ventral fins and then to its entire body. It may be stung a number of times before full acclimation occurs. The whole procedure may take as little as a few minutes to several hours. Once acclimated, though, the mucous protection may disappear upon extended separation between host and fish. Continued contact with the tentacles appears to reactivate the mucous coat. /=\
Reliance on the sea anemone hosts effects every particular life stage. Orange clownfish lays its eggs under the overhang of an anemone’s tentacles (leeward side). Arvedlund et al. (2000) believed that this was a predator-deterrence and an olfactory imprinting mechanism. The latter plays an important role in directing juveniles to the appropriate sea anemone species later on. With a leeward placement, a maximum amount of imprinting mucous can transfer between the tentacles and eggs.
Because of their relationship with sea anemone, orange clownfish has very few predatory foes as adults. Presence of danger immediately elicits a response to seek shelter deep within its host. Although adults are relatively safe from predation, the eggs of Orange clownfish are susceptible and must be guarded by the dominant male. The most common day predators are wrasses (family Labridae) and other damselfishes (family Pomacentridae). Night predators of eggs are generally not fishes but invertebrates like brittle stars (Ophiotrichidae, Ophiochimidae, and Ophiodermatidae) (Arvedlund et al., 2000). (Arvedlund, et al., 2000; Rosenberg and Cruz, 1988) /=\
Orange Clownfish Feeding, Development and Growth
According to Animal Diversity Web: Orange clownfish feeds mainly on zooplankton, such as copepods and larval tunicates. Possibly, it consumes algae from the surrounding coral reef or even leftover food portions from its host anemone. The former strategy is commonly used by pink anemonefish (A. perideraion). Frequently, orange clownfish will carry large pieces of food to its host anemone, presumably to store it for later use. The anemone, however, devours the accessible food item in most cases. [Source: Jeff Lee, Animal Diversity Web (ADW) /=]
Optimal juvenile growth rate was discovered at a ration of approximately six percent body weight per day,. Juveniles are under considerable pressure from the hierarchical structure. The individual is harassed and chased by bigger males of the “family group,” which results in stunted growth. Consequently, the smaller fish has a more restricted feeding area, and more energy must be placed on evasion. Only when a larger male is removed (such as death) will the smaller juvenile experience an acceleration in growth rate. It is believed that less time being harassed translates into more time spent on feeding. /=\
Once a juvenile, Orange clownfish must locate and inhabit a suitable anemone host. Its poor swimming ability makes it an easy target for predators. Certain chemical cues are used, and they differ among anemonefishes; this causes preferential selection for certain anemone species (Fautin and Allen, 1992). Elliott et al. (1995) found that ocean currents facilitate the locating process and that visual cues were never used. Even when a targeted anemone is already occupied, the approaching Orange clownfish does not avoid it; however, the territorial (defend an area within the home range), nature of anemonefishes causes the resident to chase away its intruder.
Orange Clownfish Mating, Reproduction and Offspring
Orange clownfish are monogamous. Pair-bond formations between male and female individuals are very strong and correlated with the small territory size that this species occupies. Despite being restricted to the immediate vicinity of its host anemone, Orange clownfish can breed and spawn year round due to the perpetually warm tropical waters they inhabit. /=\
According to Animal Diversity Web: Initiation of courtship is highly correlated with the lunar cycle. The moonlight serves to maintain a high level of alertness in the male, which then leads to increased social interaction with the female. Several days before spawning, the male will show morphological and behavioral changes: fin erection, chasing, nest preparation, and “signal jumping.” This last trait is depicted with rapid up and down swimming motions. Finally, extensions of anal, dorsal, and pelvic fins accompany the aggressiveness of the male./=\
The choice of nest site is important for later survival of the eggs. It is usually located under the tentacles of the host anemone and securely positioned on a patch of cleared rock. The male has been known to nip at the bottom edges of the tentacles in order to cause retraction, and thus providing enough clearance to clean the area. Initially, the male clears algae and debris with its mouth only later to be joined by its mate.
Actual spawning procession takes place during the morning hours, and generally lasts about 30 minutes to more than two hours. At this stage, the conical ovipositor of the female becomes visible. Several eggs are extruded through this structure with each slow and deliberate pass as the belly gently brushes the nest surface. Following closely behind is her mate, who externally fertilizes the eggs as they are laid. The number of total passes during each spawning session is high, and the amount of deposited eggs range from 100 to over 1000, depending on fish size and previous experience. Older, more experienced mating pairs will produce more eggs. The eggs of Orange clownfish are about 3-4 millimeters in length (Fautin and Allen, 1992). /=\
After egg deposition has finished, the incubation period begins. At this time, the male actively mouths and fans the eggs, while simultaneously being on guard against any predators. Because the eggs are attached to the bottom substrate via adhesive strands, additional protection is provide by the overhanging tentacles of the host anemone. Removal of dead eggs and debris is also important in keeping a well-oxygenated nest and is accomplished by the male. The female, in contrast, is occupied with feeding during this time. The average time to hatching is 6-7 days. /=\
Orange Clownfish Conservation
Humans utilize orange clownfish in the pet trade, ecotourism, research and education. They and and other anemonefishes are some of the most colorful fish species available and this makes them attractive to aquarium fish trade. They also demonstrate interesting behaviors and are easily adaptable to captivity. Consequently, these characteristics make them good reference fishes for scientific research, especially when conducting nutritional studies and determining egg and larval quality.
The depletion of coral reef habitats and marine aquarium fishes has presented a relatively new market in aquaculture. It is possible to rear orange clownfish in controlled conditions, and it may eventually play a significant role in maintaining stable populations. At present, this species is not threatened or Endangered. It is not on the International Union for Conservation of Nature (IUCN) Red List and has no special Convention on International Trade in Endangered Species (CITES) status.
Due to the increased aquarium trade there have been tremendous developments in rearing of marine fishes using aquaculturing techniques. One of the most challenging obstacles is providing an economical, yet effective, feed in an artificial environment. Hoff (1996) found that Orange clownfish larvae and juveniles could be successfully reared on highly integrated and diverse feeds, such as rotifers, small particulate dry feed, Artemia, and krill meal. Unfortunately, this proved too expensive to be practical, and a regime solely based on artificial feed decreased survival and growth rates in young fishes. If, however, juveniles were weaned from live Artemia 15 to 20 days after hatching and fed a fish meal-casein-based substitute, survival and growth rates showed no difference from juveniles fed entirely on live feed. /=\
Image Sources: Wikimedia Commons; YouTube, Animal Diversity Web, NOAA, group pictures from researchgate, EvoDevo and Oceans, Reefs and Aquariums (ORA)
Text Sources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.
Last Updated March 2023