Chaetodontidae (butterflyfish) captive breeding overview: Current thoughts on keeping, mating, spawning and rearing of these beautiful fish (Note: I last wrote an overview of the butterflyfish in collaboration with prior work done by Anderson Monteiro [aomont] in 2009. I will be relying heavily on that information for this current document.)
When I last wrote a summary of current knowledge about butterflyfish not much was known about their spawning or larvae. In fact, many, many reef aquarium sites still repeat that butterflyfish have not or cannot be bred in captivity. (For example,
http://www.fishchannel.com/fish-species/saltwater-profiles/yellow-longnose-butterflyfish-2.aspx or
http://animal-world.com/encyclo/marine/butter/butter.php#Breeding:). Fortunately, these reports are not true as has emphatically disproven by Matt Wittenrich:
http://risingtideconservation.blogspot.com/2011/11/schooling-bannerfishso-close.html and
http://www.reefs.com/blog/2011/11/28/larval-heniochus-butterflyfish-prove-collaborative-breeding-can-work/.
Given Matt's success--getting Heniochus diphreutes, the Schooling Bannerfish to 41 days--I thought it was probably time to update what is known about these beautiful species in the hope that it might spur others' to attempt "the impossible."
Some of the species covered in this document: The Family Chaetodontidae,
including: Chaetodon auriga, the Threadfin butterflyfish (
http://upload.wikimedia.org/wikipedia/commons/3/38/Chaetodon_auriga_setifer.jpg Chaetodon lunula, the Raccoon butterflyfish (
http://www.fleurey.com/weblogs/franck/images/poissons/poisson59.jpg)
Chaetodon semilarvatus, the Bluecheek butterflyfish (
http://www.flmnh.ufl.edu/fish/Gallery/Descript/GReefShark/butterflyfish.JPG)
Chaetodon plebius, my favorite Bluespot butterflyfish (
http://www.ryanphotographic.com/images/JPEGS/Chaetodon%20plebeius,%20Blue-spot%20butterflyfish,%20Fiji,%202007.jpg The other fish of
Chaetodon Chelmon rostratus, the Copperband butterflyfish (
http://saltwater.tropicalfishandaquariums.com/Butterfly/Copperband.JPG)
Forcipiger longirostris, the Longnose butterflyfish (
http://www.underwaterkwaj.com/uw-misc/butterfly/Forcipiger-longirostris-jj-0072-090709.jpg)
Heniochus acuminatus, the Pennant coralfish (
http://animal-world.com/encyclo/marine/butter/images/BlackandWhiteHeniochusWMBu_C800.jpg)
Heniochus diphreutes, the Schooling Bannerfish or False Moorish Idol (
http://www.ryanphotographic.com/images/JPEGS/Heniochus%20diphreutes%20Schooling%20bannerfish%20big%20school,%20Kadavu,%20Fiji%202004.jpg and many more.
Common Characteristics of the Group The different species in this genus run the gamut in many ways: Some species are group spawners, some are monogamous with long-term pair-bonds (I've seen reports of pair-bonds of at least six years); some are omnivores, some planktivores, some are thought to be obligate corallivores. It's especially important to research the species that you are interested in to see what you are in for. Fortunately, much has been written with regard to the various species in Chaetodontidae and their suitability for captivity.
For more basic information, visit:
http://www.wetwebmedia.com/BFsBestWrst.htm Creating Pairs Butterflyfish are born to separate sexes. Forming a male/female pair is quite difficult. The only reported sexual dimorphisms in Chaetodontidae is that sometimes the male will be larger than the female. When ready for spawning, the female will swell with ripening eggs. Certain butterflyfishes form long-term pair-bonds after maturation but some species (mostly the planktivores) spawn in large aggregations. Be sure to research the species that you wish to keep.
Part of the problem with pairing butterflies in captivity is that even in the wild butterflies will sometimes maintain same-sex pairs. Apparently, pairs are much better able to defend a territory. So much better, in fact, that having a pair of any type is better for survival than waiting to find a compatible partner of the opposite sex.
Capuli (as cited by Rauss) claims that Chaetodon auriga can be sexually mature at sizes of 13 cm. (
http://animaldiversity.ummz.umich.edu/site/accounts/information/Chaetodon_auriga.html)
Spawning Chaetodontidae are pelagic spawners, releasing large numbers (in the 100,000s per spawn) of very small eggs. According to Thresher:
Originally Posted by
In tropical areas available data indicate that levels of spawning activity peak in winter and early spring ..., though at least some species continue to spawn at lower levels of activity throughout the year.... (p. 266)
There is some question about whether lunar cycles affect spawning activity with a peak near the full moon, though C. nippon did not show the same rhythm spawning in captivity. (Spawning in captivity!!! See below for reference:Suzuki, et al., 1980) Other studies also did not repeat the lunar rhythm finding.
Three generalities about Butterflyfish spawning:
Originally Posted by
[F]irst, butterflyfishes typically, if not always, spawn at dusk; second, gamete release typically takes place well up into the water column following what is generally a slow ascent; and third, at least in the genus Chaetodon, courtship is usually in the form of the male swimming behind and below the female, nudging her abdomen with his snout and forehead. Spawning usually takes place with the fish in this position (Thresher, p. 266).
He goes on to describe reports of spawning in the field and then we hit the jackpot!
Originally Posted by
Finally, spawning also has been observed for a species of Chaetodon in captivity. (Thresher, p. 268)
The spawning in captivity was in a very deep tank--1.3 meters. Spawning was always after dark.
The report was made by the same Suzuki from the quote above. I'll try to provide the relevant details in the bib below.
Eggs According to Thresher, "Chaetodontid eggs are buoyant, transparent, and spherical (p. 268)." No surprise. Looks like egg diameter ranges from 0.6mm to 0.74mm depending on the different species, though it was a small sample size.
Originally Posted by
Eggs of C. nippon, the only species for which early development has been described, hatch in 28 to 30 hours at water temperaturs of 22.2 to 23.7[degrees]C. The newly hatched larvae are 1.43 to 1.53 mm long and have a large yolk sac.... A single oil droplet is located at the posterior edge of the yolk.... The yolk is largely absorbed by 48 hours after hatching, and by 72 hours the mouth and anus open, the eyes are pigmented, and pectoral fin precursors are present.... (Thresher, p. 269)
Female C. auriga release hundreds of thousands of eggs at a time (Hourigan 1989). Threadfin butterflyfish spawn frequently throughout their long breeding seasons (Roberts and Ormond 1992, as quoted in Rauss).
Larvae Eggs hatch to prolarvae (an intermediate stage at which the animals have no eyes, mouth, or guts; this stage lasts until the larva can begin to hunt) after roughly 24 hours. The prolarvae stage can last up to about three days.
Originally Posted by
Eggs of C. nippon ... hatch in 28 to 30 hours at water temperaturs of 22.2 to 23.7[degrees]C. The newly hatched larvae are 1.43 to 1.53 mm long and have a large yolk sac.... A single oil droplet is located at the posterior edge of the yolk.... The yolk is largely absorbed by 48 hours after hatching, and by 72 hours the mouth and anus open, the eyes are pigmented, and pectoral fin precursors are present.... (Thresher, p. 269)
In a very nice illustration, Thresher gives a progression of larvae from newly hatched to 3 days (2.47 mm). I believe that's the extent of the captive spawn (starvation), but there are further illustrations of 4.5mm, 5.5mm, and 10mm larvae, presumably from plankton tows.
Unknown duration of planktonic stage, but there is an estimate of several months (other authors claim roughly 40 days).
Butterflyfish larvae go throug a Tholichthys stage in which the postlarvae head have bony plates covering the body. See Rising Tide for photos.
Rearing According to Thresher, this is what Suzuki tried:
Originally Posted by
by feeding rotifers ... larval oysters ... and larval sea urchins.... Although at least a few larvae fed, none lived more than eight days (Thresher, p. 270).
Wittenrich reports that Heniochus diphreutes feeds heavily upon copepod nauplii from early in the larval stage.
Bibliography for This Document Alison Rauss, Chaetodon auriga,
http://animaldiversity.um.../Chaetodon_auriga.html Ronald Thresher, Reproduction in Reef Fishes,
http://www.amazon.com/Reproduction-Reef-Fishes-Ronald-Thresher/dp/0876668082/ref=sr_1_1?ie=UTF8&qid=1350772636&sr=8-1&keywords=ronald+thresher Rising Tide, Schooling Bannerfish...So Close!,
http://risingtideconservation.blogspot.com/2011/11/schooling-bannerfishso-close.html Other Articles and Papers Katsumi Suzuki, Yoichi Tanaka and Syozo Hioki, Spawning Behavior, Eggs, and Larvae or the Butterflyfish, Chaetodon nippon, in an Aquarium,
http://www.wdc-jp.biz/pdf_store/isj/publication/pdf/26/264/26404.pdf TANAKA YOICHI, HIOKI SHOZO, SUZUKI KATSUMI. 2001. "Spawning Behavior, Eggs, and Larvae of the Butterflyfish, Chaetodon modestus in an Aquarium." Journal of the Faculty of Marine Science and Technology, Tokai University VOL. 51, pp. 89-100.
Abstract:
Originally Posted by
Spawning behavior and early life history of Chaetodon modestus TEMMINCK et SCHLEGEL are described in detail from aqurium observations. The early life history of the present species is the third record among the family Chaetodontidae. Spawning of C. modestus, in captivity, and it occurs between multiple males and one female in the night(between 18:00-22:00 hrs.), in almost every day during about eighteen months(from Aug. 14, 1978 to Jan. 31, 1080) at water temperatures of 18.6-26.5.DEG.C.. Fertilized eggs are buoyant, spherical, and colorless. They measure 0.75- 0.80mm in diameter and contain a single oil globule measuring 0.18-0.19 mm in diameter. Hatching takes place 15hrs. 50min. after fertilization at water temperatures of 25.8-28.8.DEG.C.. Newly hatched larvae measure 1.40-1.50mm in total length, have a large ovoid yolk 0.75-0.77mm in long axis, and have 25-26 myomere(12-13+13=25-26). An oil globule is situated at the rear of the yolk. Early larval stages of C. modestus are described for eihgt days after hatching. The mode of reproduction and the characteristics of developing eggs and larvel stages of this species are compared with Chaetodon nippon and C. daedalma both previously studeid. (author abst.)
From here:
http://sciencelinks.jp/j-east/article/200113/000020011301A0329215.php Jeffrey M. Leis and Michelle N. Yerman (2012) Behavior of Larval Butterflyfishes (Teleostei: Chaetodontidae) at Settlement on Coral Reefs. Copeia: June 2012, Vol. 2012, No. 2, pp. 211-221.
Abstract:
Originally Posted by
Behavior of settlement-stage (10ā17 mm SL) larvae of five chaetodontid species (Chaetodon auriga, C. aureofasciatus, C. rainfordi, C. plebeius, and Chelmon rostratus) captured in light traps was investigated in open water and over coral reefs at Lizard Island, Great Barrier Reef. Average swimming speeds of all species in open water (18ā26 cm sā1) were greater than average current speeds; larvae swam several meters deeper off the deeper east side of the island than off the west side, and most larvae swam directionally. Near coral reefs, about 37% of larvae swam offshore at speeds that were frequently greater than those at which they swam toward or over reefs. After a mean of 5 min, 40% of larvae reaching reefs swam away offshore, many after harassment by resident fishes. About 5% were eaten; the rest settled in a mean of 2 min. Chaetodon plebeius never settled. Non-predatory resident fishes strongly influenced the distribution of butterflyfish settlers. The three species that settled in usable numbers had species-specific settlement depths and substratum, primarily live corals. Comparing these results to studies on larger juveniles shows that individuals become increasingly selective about habitat (usually coral taxa) as they grow. Larval settlement behavior of chaetodontids is more similar to that of pomacentrids than that of lutjanids or serranids, but some features are shared by all families.
From here:
http://www.asihcopeiaonline.org/doi/abs/10.1643/CE-10-185?journalCode=cope Jeffrey M. Leis. "Larval biology of butterflyfishes (Pisces, Chaetodontidae): what do we really know?" 1989. Environmental Biology of Fishes Volume 25, Numbers 1-3 / May, 1989, pp. 87-100.
Originally Posted by
Relatively little is known of the pelagic portion of the life history of butterflyfishes. Eggs are small (<1 mm), pelagic and hatch in less than 30 hours. Most species pass through a so-called tholichthys larval interval characterized by elaborate, distinctive head spination:Coradion larvae have different head spination. While older chaetodontid larvae can be identified by adult characters, young (preflexion) larvae generally cannot now be identified below family. In tropical plankton studies chaetodontid larvae averaged <0.1% of larvae captured, and occurred in 13% of samples. This rarity is a major hindrance to further work, but is not unexpected in view of adult abundance. Larvae of a few taxa are most abundant in shelf waters, but larvae of many chaetodontid taxa seem to be most abundant in oceanic waters. In either case, waters near reefs have the fewest chaetodontid larvae. Offshore maxima of larvae appear to exist a few kilometers seaward of Great Barrier Reef ribbon reefs. Chaetodontid larvae may prefer the upper portion of the water column. Both size and age at settlement vary widely within the family and the large genusChaetodon, and the latter varies widely within species. Average size at settlement is less than 20 mm and age is less than 40 days. No correlation was found between size and age at settlement. Behaviour and feeding of chaetodontid larvae are essentially unstudied. Chaetodontid larvae seem to be least abundant in winter. The implications of these conclusions are discussed and some suggestions for further research are made. In all areas more work is needed.
From here:
http://www.springerlink.com/content/8kh71073263j6661/?MUD=MP Journals: Chaetodon striatus:
http://www.lsmac.org/smf/index.php?topic=357.0 Chaetodon capistratus:
http://www.lsmac.org/smf/index.php?topic=354.0