sign in sign up
<<
Home , Acanthopterygii, Acanthuridae, Carangiformes, List of fish families, Ocellaris clownfish, Pearlfish

OEB 130: BIOLOGY OF Lecture 20: reef fishes

Outline

Labs in the NW lab, this Thurs./Friday (wear older clothes if possible, although we’ll have plastic aprons too)

Lecture outline: • Overview of habitats • Diversity of fishes on coral reefs Brief review of major groups covered so far Some additional important families on the reef • Coral reef biology: some key issues Invasive Loss of reef area and damage to reef habitats The value of marine reserves for fish populations Some aspects of reproduction by reef fishes Cleaner fishes and cleaning stations Mimicry Florescent fishes Overview of coral reef habitats Coral reefs are diverse and complex fish habitats; ~ 8,000 species of fishes on reefs worldwide Overview of coral reef habitats

Corals grow in the tropical regions where water stays ~ 20 deg C. Overview of coral reef habitats

• Very specific requirements: • Coral likes areas with some – Temperature: 73-75F waves: – Depth: sea surface to – They are strong enough ~ 200 feet to withstand the pressure – Salinity: Normal salt – New supply of levels (35ppt) water means more food – Light: Zooxanthellae – Waves remove silt need light to survive – New water brings more – Sedimentation: Being oxygen covered with silt interferes with photosynthesis – Desiccation: being exposed to air. Most coral will die if exposed too long Overview of coral reef habitats Types of reefs: (1) fringe reefs Overview of coral reef habitats Types of reefs: (2) Barrier reefs Overview of coral reef habitats

The Great Barrier Reef Overview of coral reef habitats Types of reefs: (3) Atoll reefs Overview of coral reef habitats

Atoll Reef Fulanga (in Figi) Overview of coral reef habitats

Atoll Formation: Darwin first understood this process Overview of coral reef habitats Atoll Formation: Darwin (1842) first understood this process

“Fringing-reefs are thus converted in to barrier-reefs; and barrier-reefs, when encircling islands, are thus converted into atolls, the instant the last pinnacle of land sinks beneath the surface of the ocean.” Darwin, 1842 Overview of coral reef habitats

A great diversity of habitats in coral reefs Overview of coral reef habitats

Many niches may facilitate evolutionary specialization and diversification

Alfaro, M. E., Santini, F. and Brock, C. D. (2007). Do reefs drive diversification in marine ? Evidence from the pufferfish and their allies ( ). Evol. 61, 2104-2126. Overview of coral reef habitats

Many niches may facilitate evolutionary specialization and diversification

Alfaro, M. E., Santini, F. and Brock, C. D. (2007). Do reefs drive diversification in marine teleosts? Evidence from the pufferfish and their allies (Order Tetraodontiformes). Evol. 61, 2104-2126. Overview of coral reef habitats Many niches may facilitate evolutionary specialization and diversification

Alfaro, M. E., Santini, F. and Brock, C. D. (2007). Do reefs drive diversification in marine teleosts? Evidence from the pufferfish and their allies (Order Tetraodontiformes). Evol. 61, 2104-2126. Diversity of fishes on coral reefs

A key feature of coral reefs: very high biodiversity Recall acanthomorph relationships Diversity of fishes on coral reefs Some of the major groups of fishes on reefs:

• (soldierfishes, squirrelfishes) • (, ) • (scorpionfishes, lionfishes) • Tetraodontiformes (, boxfishes, porcupine fishes) • Labroidei: Labridae (); Scaridae () • Gobioidei: • Blennioidei: blennies • (, anemonefishes) • (jacks) • (groupers, sea basses) • (snappers); (porgies) • Haemulidae (grunts); (drums, croakers) • Mullidae (); Chaetodontidae () • (angelfishes), • (surgeonfishes), • (spadefishes); Zanclidae (moorish idols)

The Percomorpha– more detailed branching

Xiphiformes Pleuronectiformes , () (pp. 223-226) Carangids (jacks) Anabantoids Swampeels etc. (pp. 173-174) Gobies, Many more Cardinalfishes

(pp. 218-222) (Next phylogeny (Next phylogeny slide) (jacks and relatives)

Tunas, seahorses and relatives

Diversity of fishes on coral reefs: most are Percomorpha The Percomorpha – more detailed branching

Mullets,

Surfperches Pomacentridae Blennies (pp. 214-217) (Damselfishes) Cichlidae (pp. 205-208) () (silversides, Clingfishes (pp. 200-204) , (pp. 142-143) live-bearing fishes

(pp. 144-156)

Many Many more (Next phylogeny (Next phylogeny slide) Eupercaria Jacks and relatives, , labyrinth fishes, and others

Diversity of fishes on coral reefs: most are Percomorpha : a very important The Percomorpha – more detailed branching , , Groupers Sculpins (pp. 171-172) Icefishes (pp. 175-180) (pp. 195-199) Zoarcids Kyphosidae

Sunfishes Hawkfishes (Sea chubs)

Wrasses, parrotfishes,

and relatives Many more

(pp. 209-213) (Next phylogeny (Next phylogeny slide)

Some Scorpaeniform -like fishes fishes

Ovalentaria Diversity of fishes on coral reefs: most are Eupercaria Percomorpha The Percomorpha – more detailed branching

Lophiiformes () (pp. 137-141) Tetraodontiforms Butterflyfishes Sparidae (puffer fishes Lutjanidae and relatives) (Angelfishes) (pp. 227-231) Haemulidae Sciaenidae Pomacanthidae Surgeonfish

Sunfishes and some other perch-like fishes Scorpaeniform fishes

Diversity of fishes on coral reefs: most are Percomorpha : Percomorpha: Pomacentridae

• Pomacentridae: damselfishes, clownfishes, anemonefishes (~390 species) • Tropical and primarily indo-pacific, very colorful Acanthopterygii: Percomorpha: Pomacentridae

• Pomacentridae: damselfishes, clownfishes, anemonefishes (~390 species) • Tropical and primarily indo-pacific, very colorful Acanthopterygii: Percomorpha: Sparidae

• Sparidae: porgies, scup, bream, sheepshead (~140 species) • Atlantic, Indian, and pacific; marine tropical to temperate, some ok in brackish waters • Important food fish Acanthopterygii: Percomorpha: Haemulidae

Agassiz fish story: "When do you wish to begin?" he asked. "Now," I replied. This seemed to please him, and with an energetic "Very well!" he reached from a shelf a huge jar of specimens in yellow alcohol. "Take this fish," he said, "and look at it; we call it a haemulon; by and by I will ask what you have seen."

• Haemulidae: grunts (132 species) • Marine, brackish waters Acanthopterygii: Percomorpha: Sciaenidae

Spotted drum

• Sciaenidae: drums, croakers (291 species) • Marine, brackish, and freshwater; produce loud sounds with the swimbladder Acanthopterygii: Percomorpha: Mullidae

• Mullidae: goatfishes (~85 species) • Marine, brackish waters; barbels used for benthic food location • Not mullets! Mullets (Mugilidae) are in the Ovalentaria • Related to seahorses and pipefishes: early offshoot of this clade Acanthopterygii: Percomorpha: Chaetodontidae

• Chaetodontidae: butterflyfishes (131 species) • Atlantic, Indian, and pacific waters; body laterally compressed • Bright coloration, eyespot often present, usually live in shallow waters • Some species have a specialized -swimbladder connection Acanthopterygii: Percomorpha: Chaetodontidae Acanthopterygii: Percomorpha: Chaetodontidae

Have a specialized lateral line-swimbladder connection Acanthopterygii: Percomorpha: Chaetodontidae

Butterfly fishes have a special connection between the lateral line and the swimbladder – all 3 systems are interconnected

Webb, J. and Smith, W. (2000). The laterophysic connection in chaetodontid : morphological variation and speculations on sensory function. Phil. Trans. Royal Soc. B: Biol. Sci. 355: 1125. Acanthopterygii: Percomorpha: Chaetodontidae Acanthopterygii: Percomorpha: Lutjanidae

• “snappers” • Marine tropical • 109 species • Important food fishes : Ophiidiformes (; cusk )

Pearlfish often live in association with marine , such as sea cucumbers, entering and leaving through the anus. This group is at the base of the Percomorpha; a number of deep-sea species too; ~260 total species Acanthopterygii: Percomorpha: Pomacanthidae

• Pomacanthidae: angelfishes (88 species) • Marine, shallow tropical waters; colorful • Color may change dramatically from young to adult • Not the freshwater angelfish, which is a ! Acanthopterygii: Percomorpha: Pomacanthidae

adult young

Juvenile and adult coloration can be quite different in reef fishes Acanthopterygii: Percomorpha: Pomacanthidae

adult young

Juvenile and adult coloration can be quite different in reef fishes Acanthopterygii: Percomorpha: Acanthuridae (~85 species)

Doctorfish/surgeonfish/tangs ( chirurgus): some biology

Acanthurus is derived from the Greek "acantha" which means thorn, and the Greek "oura" which means tail.

Distribution This is the most wide-ranging of the species of Acanthurus in the Atlantic and is found from Massachusetts to Brazil, including the northern Gulf of Mexico and the Caribbean. It can also be found along the tropical western coast of Africa. Biology Of particular interest is the sharp, scapel-like spine that is located on each side of the body on the caudal peduncle. This spine can be extended and used to fend off aggressive encounters. Its teeth, specialized for scraping , are spatula-like in shape, close together, and notched on the edges.

Acanthopterygii: Percomorpha: Acanthuridae

Yellow tang

Convict tang Powder brown tang Acanthopterygii: Percomorpha: Acanthuridae

Unicornfish

Orangespine unicornfish - lituratus Acanthopterygii: Percomorpha: Acanthuridae Doctorfish (Acanthurus chirurgus): some biology

Doctorfish Larva

Reproduction

Doctorfish spawning is a group event that occurs during evening hours. The eggs are small, less than a millimeter in diameter, pelagic, and each contains a single droplet of oil for flotation. The eggs hatch in twenty-four hours, revealing small, translucent larvae. The newly hatched larvae are referred to as acronurus because it was once thought to represent a separate of fishes, the genus Acronurus. The larvae are diamond-shaped and laterally compressed, with a head shaped like a triangle. The scalpel does not appear until the acronurus reaches about 13 mm in length. Late post-acronurus drift inshore, where they change into juveniles. The acronurus lose their silver color and turn brown. Their profiles become round.

The prominent dorsal and anal spines that are characteristic to the acronurus reduce, while the scalpel gets bigger. Complete metamorphosis takes about a week, after which two-inch long juveniles settle onto the bottom of a suitable inshore habitat. Juveniles grow rapidly, attaining sexual maturity in as little as nine months. The adults can reach sizes of up to 14 inches (35 cm) in length.

Acanthopterygii: Percomorpha: Labridae (wrasses)

~640 species including the parrotfishes Marine, tropical, very common on reefs Excellent pectoral fin swimmers Some species eat parasites off of other fishes

Interesting reproductive modes: most are “protogynous hermaphrodites” – all born as females, then can switch to male;

Sex change a common theme in this group Acanthopterygii: Percomorpha: Scaridae (parrotfishes)

Closely related to wrasses – often included in the Labridae ~ 88 species when considered separately

Teeth form a parrot-like beak with which they rasp algae from coral and other rocky substrates

Form a mucus cocoon at night Acanthopterygii: Percomorpha: Zanclidae

“gill”

• Zanclidae: moorish idols (1 species); marine tropical indo-Pacific • No spine on caudal peduncle; tropical indo-pacific • Eats invertebrates and algae Acanthopterygii: Percomorpha: Ephippidae

• Ephippidae: spadefishes (16 species) • Marine: atlantic, Indian, Pacific waters Coral reef biology: some key issues biology: invasive species Coral reef habitats face many threats

Scorpaeniformes: Pterois volitans, red lionfish (native to the Pacific) Coral reef fish biology: invasive species

Lionfishes were first reported in Atlantic waters in the 1990s and have since become established along the U.S. east coast from Florida through North Carolina and east to Bermuda. They are also common throughout the Bahamas and Caribbean islands. They have been sighted as far south as Colombia and the Netherlands Antilles and as far east as the U.S. Virgin Islands. Their expansion has been extremely rapid. Coral reef fish biology: invasive species Coral reef fish biology: invasive species Coral reef fish biology: damage to reefs

U.S. Role in Aquarium Trade

U.S. imports: Trade in Live Coral: Importing Countries 80% of all live . 700 Other Canada 600 Asia 95% of the “live rock” Europe 500 United States

400 50% (8 million) marine aquarium fish per year. 300

200 Concerns: over , cyanide,

100 handling, transport practices. Volume (thousands of colonies) (thousands Volume 0 1988 89 90 91 92 93 94 95 96 97 1998 Coral reef fish biology: damage to reefs Coral Reef Bleaching When stressed, corals become whitened (“bleached”) from the loss of the zooxanthellae. This can result from UV radiation or prolonged high temperatures. Regions where the sea surface temperature is 1 C greater than the maximum expected summer time temperature are highlighted on the map. The color scale indicates anomalies greater than 1.0 C in yellow in red, with anomalies between 0.25 to 1.0 C in purple to blue. The yellow to red colors indicate potential coral bleaching. Coral reef fish biology: damage to reefs Coral Bleaching and Temperature Monthly anomalies of sea surface temperature Papua New Guinea (Davies et al.1997)

Extensive coral bleaching The value of marine reserves for fish populations

Length-frequency distribution of catch of

Epinephelus striatus

Heavily fished reefs

Unexploited

reef areas

20 30 40 30 20

Numbers

10

0 0 30 40 50 60 70 80 90 Total length (cm) The value of marine reserves for fish populations

The effect of increases in length on fecundity of some Caribbean reef fishes Family and Species % increase % increase in in length fecundity Serranidae Cephalopholis fulva 5 76 Epinephelus guttatus 17 278 Haemulidae Haemulon plumieri 22 214 Chaetodontidae Chaetodon capistratus 18 82 C. ocellatus 16 412 Pomacanthidae Pomacanthus paru 8 18 The value of marine reserves for fish populations

Change in large in Apo Island reef reserve (in the Philippines)

Reserve

)

Non-reserve 2

2 4 6 8 10 8 6 4 2 Mean Density (no/1000m Density Mean 2 4 6 8 10 12 Years of Reserve Protection Coral reef fish biology: reproduction

Many fascinating aspects of coral reef fish reproductive biology

Anemonefish eggs (attached to bottom) -- remember the Ovalentaria -- Coral reef fish biology: reproduction Clownfish live in small groups inhabiting a single anemone. The group consists of a breeding pair, which cohabit with a few non- reproductive, "pre-pubescent", and smaller male clownfish. When the female dies, the dominant male changes sex and becomes the female. This life history strategy is known as sequential hermaphroditism. Because clownfish are all born as males, they are protandrous hermaphrodites (pro=first; androus=male).

Clownfish are initially male; the largest fish in a group then becomes female.

Amphiprion ocellaris (clownfish) are born with active male and dormant female reproductive organs. The dominate fish will "change" from male to female (protandrous hermaphroditism). She will then mate with the largest male. The fish lay their eggs in a safe spot close to the anemone for protection, usually on a smooth surface; it usually takes 6-7 days for the eggs to hatch. During this time the male is very protective over the nest. The mother usually lays 100 to 1000 eggs in the morning. The male fertilizes the eggs when they come out (external fertilization). A. ocellaris will maintain water flow over their eggs by fanning them with their fins. They will also remove dead or dying eggs from the clutch in order to reduce the chance of bacteria concentrating around the egg and killing off surrounding eggs. Coral reef fish biology: reproduction So … in the movie “Finding Nemo”, Nemo should have changed sex into a female after his fathers “wife” was eaten by a , and then mated with his father. Coral reef fish biology: reproduction Patterns of hermaphroditism in fishes

At least 14 families of Percomorpha display sex change: Protogyny: female first, seen in Labridae, Scaridae, Serranidae Protandry: male first, Pomacentridae (Nemo) Synchronous (quite rare), seen in Serranidae, genus Hypoplectrus

Percomorpha: Serranidae, Hypoplectrus Coral reef fish biology: reproduction

Percomorpha, Why change Gobiodei: sex? Gobiodon

Hobbs, J., Munday, P. and Jones, G. (2004). Social induction of maturation and sex determination in a coral reef fish. Proceedings of the Royal Society of London. Series B: 271: 2109. Coral reef fish biology: cleaner fishes

A mutualistic : both cleaner and host benefit: host fish carry a variety of parasites, esp. isopods, which feed on the skin and mucus of reef fish. Coral reef fish biology: cleaner fishes

A mutualistic symbiosis: both cleaner and host benefit. Wrasses (Labridae) are well-known . Coral reef fish biology: mimicry The cleaner-fish–fangblenny mimic study system.

The receiver: needs to The real cleaner fish: The mimic cleaner fish eats distinguish between the real eats parasites from the scales, mucus, and dermal cleaner and the mimic. . tissue from the damselfish – it is an aggressive mimic.

Cheney, K. L. and Côté, I. M. (2007). Aggressive mimics profit from a model– signal receiver . Proc. Royal Soc. B 274, 2087-2091. Coral reef fish biology: mimicry

Cheney, K. L. and Côté, I. M. (2007). Aggressive mimics profit from a model– signal receiver mutualism. Proc. Royal Soc. B 274, 2087-2091. Coral reef fish biology: mimicry

Number of pre-emptive chases by parasitized (black bars) and unparasitized (grey bars) staghorn damselfish towards cleaner fish and fangblenny mimics. Coral reef fish biology: mimicry

Cheney, K. L. and Marshall, N. J. (2009). Mimicry in coral reef fish: how accurate is this deception in terms of color and luminance? Behavioral Ecology 20, 459-468. Coral reef fish biology: mimicry

Cleaner

Mimic

Spectral reflectance curves. Black solid lines: model species; Black dashed lines, aggressive mimic.

Cheney, K. L. and Marshall, N. J. (2009). Mimicry in coral reef fish: how accurate is this deception in terms of color and luminance? Behavioral Ecology 20, 459-468. Coral reef fish biology: fluorescence

Sparks JS, Schelly RC, Smith WL, Davis MP, et al. (2014) The Covert World of Fish Biofluorescence: A Phylogenetically Widespread and Phenotypically Variable Phenomenon. PLoS ONE 9(1): e83259. doi:10.1371/journal.pone.0083259 Coral reef fish biology: fluorescence

Diversity of fluorescent patterns and colors in marine fishes.

Still of unknown significance and role in communication among individuals, recognition, and predation Coral reef fish biology: fluorescence

Interspecific variation in fluorescent emission pattern in two congeneric and sympatric members of the lizardfish genus Synodus. Bottom: Interspecific variation in coloration and pigmentation pattern under white light.