Territorial and Reproductive Behavior of the Three Caribbean Razorfishes of the Genus Xyrichtys (Labridae) at Bonaire

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aqua, International Journal of Ichthyology

Territorial and reproductive behavior of the three Caribbean Razorfishes of the Genus Xyrichtys (Labridae) at Bonaire

David C. Shen ¹* and Eugenie Clark2**

1) 16205 N. Timberline Drive, Reno NV 89511 USA 2) Senior Research Scientist, Mote Marine Laboratory, Sarastota, FL 34236, USA *Corresponding author: [email protected] ** Deceased February 25, 2015

Received: 27 January 2015 – Accepted: 10 November 2015

Abstract 1986 und 2013 durch. An der einen Stelle mit dem lokalen We conducted field studies of the three known species of Namen „Red Slave“ gab es 1985 eine große Kolonie des Caribbean razorfishes of the genus Xyrichtys at four study Rosa Messerfisches X. martinicensis und eine kleine Kolonie sites in Bonaire during 1984, 1985, 1986, and 2013. At des Grünen Messerfisches X. splendens; 28 Jahre später, one site locally named “Red Slave,” a large colony of rosy 2013, war die Situation im Wesentlichen genauso. An dem razorfish, X. martinicensis and a small colony of green ra- Ort mit dem Namen „Mi Cas“ kamen sowohl 1984 als auch zorfish, X. splendens, were essentially the same during 1985 29 Jahre später, 2013, alle drei Arten vor: X. martinicensis, X. and 28 years later in 2013. At “Mi Cas,” all three species, splendens und der Perlmuttweiße Messerfisch, X. novacula. X. martinicensis, X. splendens, and the pearly razorfish, X. An der Fundstelle „Triple Whammy“ im Hafen von Kral- novacula, were present both in 1984 and 29 years later in endijk gab es Mitte der achtziger Jahre alle drei Arten, doch 2013. “Triple Whammy” in the Kralendijk harbor con- war 2013 kein erneuter Nachweis möglich, weil inzwischen tained all three species in the mid-eighties, but in 2013 das Tauchen im Hafen verboten worden war. Doch konnten their presence could not be observed because diving in the unmittelbar südlich vom Hafen, bei „Double Whammy“, harbor was prohibited. However, just south of the harbor wo nur 2013 eine Untersuchung durchgeführt wurde, eine at “Double Whammy,” the site that was only studied in kleine Kolonie von X. martinicensis und ein Harem von X. 2013, did contain a small colony of X. martinicensis and splendens festgestellt werden. Alle drei Arten verhalten sich one harem of X. splendens. All three species are antagonis- antagonistisch, sowohl zwischen- als auch innerartlich, sie tic interspecifically and intraspecifically, defend their own verteidigen ihr Revier und bilden eine Hackordnung mehr territories, and have a pecking order based roughly on size. oder weniger entsprechend der Größe der einzelnen Exem- We mapped out colonies from individual territory borders plare. Wir konnten individuelle Reviergrenzen, Harems- to harem borders to colony borders. We observed their use grenzen und Koloniegrenzen feststellen. Und wir konnten of “dive sites,” spots in their sandy habitat within their ihre Bildung von „Tauchplätzen“ nachweisen, Stellen im own territory into which they would dive when in danger sandigen Habitat im eigenen Revier, wohin sie sich bei or for the night. Each fish had two or more of these “dive Gefahr und während der Nacht zurückzogen. Jeder Fisch sites,” which they maintained. We observed 155, 57, and hatte zwei oder mehr von derartigen „Tauchplätzen“, die 94 spawnings of X. martinicensis, X. splendens, and X. no- gepflegt wurden. Wir beobachteten 155, 57 und 94 Laich- vacula, respectively. Spawnings occurred in the late after- ablagen bei X. martinicensis, X. splendens bzw. X. novacula. noon before sunset. There was some egg cannibalism Das Ablaichen fand am späten Nachmittag vor Sonnenun- among X. martinicensis and X. splendens, but not with X. tergang statt. Bei X. martinicensis und X. splendens gab es Ei- novacula. We syringed eggs for lab observation and timed Kannibalismus, nicht aber bei X. novacula. Wir entnahmen their hatching. Feeding behavior of each species as well as mit einer Spritze Eier zur Laboruntersuchung und um die observed interactions with other species are discussed. Schlupfzeiten festzustellen. Diskutiert werden das Nahrungsverhalten der einzelnen Arten sowie die Interaktio- Zusammenfassung nen mit anderen Arten, die beobachtet werden konnten. Die Freilandstudien an den drei bekannten Arten karibis- cher Messerfische der Gattung Xyrichtys führten wir an vier Résumé Untersuchungsstellen bei Bonaire in den Jahren 1984, 1985, Nous avons établi des études de terrain des trois espèces

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connues de poissons-rasoirs des Caraïbes du genre Xyrichtys soliti infilarsi in caso di pericolo o per la notte. Ogni pesce sur cinq sites d’étude à Bonaire en 1984, 1986 et 2013. Sur mantiene due o più di questi "siti di immersione". Abbia- un des sites, qui porte le nom local de « Red Slave », une mo osservato 155, 57 e 94 deposizioni di uova di X. mar- grande colonie du poisson-rasoir rosé, X. martinicensis et tinicensis, X. splendens e X. novacula rispettivamente. Tali une petite colonie du poisson-rasoir vert, X. splendens, deposizioni si verificavano nel tardo pomeriggio prima del étaient pour l’essentiel identiques en 1985 et 28 ans plus tramonto. Sono stati registrati sporadici eventi di canniba - tard, en 2013. A « Mi Cas », les trois espèces, X. martini- lismo delle uova tra gli individui di X. martinicensis e X. censis, X. splendens et le poisson-rasoir perlé, X. novacula splendens, ma non tra quelli di X. novacula. Abbiamo étaient présents en 1984 et 29 ans plus tard, en 2013. « siringato alcune uova per l'osservazione in laboratorio e de- Triple Whammy », dans le port de Kralendijk, contenait terminato i tempi di schiusa. Infine, sono stati sudiati il les trois espèces au milieu des années quatre-vingt, mais, en comportamento alimentare di ogni specie e le interazioni 2013, leur présence n’a pu être observée parce que la osservate con le altre specie. plongée dans le port était interdite. Néanmoins, un peu au sud du port, à « Double Whammy », le site qui n’a été prospecté qu’en 2013, contenait une petite colonie de X. INTRODUCTION martinicensis et un harem de X. splendens. Benthic fishes living in tropical sand environments Les trois espèces sont antagoniques intra- et interspéci- near coral reefs escape their enemies with adapta- fiquement, défendent leurs propres territoires et ont une tions such as camouflage, building burrows, and hiérarchie basée en gros sur la taille. Nous avons observé diving head first into the sand. Wrasses (Family: leur usage de sites de « plongée », des emplacements dans Labridae) of the circumtropical genus Xyrichtys, leur habitat de sable, dans leur propre territoire, où ils known as razorfishes because of their sharp head plongent face au danger ou pour la nuit. Chaque poisson a deux ou plus de ces sites de « plongée » qu’ils maintien- profile (helpful when diving into the sand), live in nent. Nous avons observé 155, 57 et 94 pontes respective- extensive sand bed habitats and are one of the most ment de X. martinicensis, X. splendens et X. novacula. common and widely distributed of the sandfishes. Les pontes survenaient tard l’après-midi avant le coucher Three species of razorfishes, genus Xyrichtys, are du soleil. Il y avait un peu de cannibalisme des œufs parmi known from the Caribbean: X. novacula, the pearly X. martinicensis et X. splendens, mais pas pour X. novacula. razorfish (Figs 1a and b); X. splendens, the green ra- Nous avons prélevé des œufs pour observation en labo zorfish (Figs 2a and b); and X. martinicensis, the et avons chronométré leur éclosion. Nous discutons égale- rosy razorfish (Figs 3a and b) (Randall 1965, Böh- ment le comportement alimentaire de chaque espèce ainsi que les interactions observées avec d’autres espèces. lke & Chaplin 1968, Robins et al. 1991). In con- nection with our studies of sandfishes in the Red Sea (Clark & Shen 1986, Clark et al. 1990, 1991, Sommario Clark & Pohle 1992), Papua New Guinea (Clark & Abbiamo condotto studi sul campo delle tre specie Pohle 1996), and the Caribbean (Clark et al. 1988, conosciute di pesci rasoio caraibici del genere Xyrichtys in quattro siti presso l’isola di Bonaire nel 1984, 1985, 1986 Konstantinou & Shen 1995, Scarr 1986, Nemtzov e 2013. In un sito conosciuto localmente come "Red & Clark 1994), we studied the three known species Slave", una grande colonia di pesci rasoio roseo, X. mar- of Caribbean razorfishes, all of which are common tinicensis, e una piccola colonia di pesci rasoio verde, X. at Bonaire. Our field studies took place mainly at splendens, erano essenzialmente immutate durante il 1985 three sites in Bonaire during January and February e 28 anni dopo, nel 2013. A "Mi Cas" tutte e tre le specie, 1984; January, May, and June 1985; February, X. martinicensis, X. splendens, e il pesce rasoio perlato, X. March, and April 1986; and November 2013. novacula, erano presenti sia nel 1984 e 29 anni dopo, nel Razorfishes, like many sand-dwelling fishes, are 2013. A "Triple Whammy" nel porto di Kralendijk erano presenti tutte e tre le specie a metà degli anni Ottanta, ma protogynous hermaphrodites (changing sex from nel 2013 non è stato possibile osservarne la presenza per- female to male) and live in polygynous social sys- ché le immersioni nel porto erano proibite. Tuttavia, appe- tems. The larger male (previously a female) main- na a sud del porto, a "Double Whammy", il sito che è stato tains a territory, and at dusk mates with up to 7 fe- studiato solo nel 2013, sono state registrate una piccola males. The females usually live in sub-territories colonia di X. martinicensis e un harem di X. splendens. within the male’s territory (Baird 1988, Baird & Tutte e tre le specie sono antagoniste interspecificamente Liley 1989, Clark 1983, Nemtzov 1985, Victor e intraspecificamente, difendono i propri territori e hanno 1987). This paper presents the results of our stud- una gerarchia basata approssimativamente sulle dimen- sioni. Abbiamo tracciato i territori di singoli individui, i ies on the three species of Xyrichtys with regard to confini degli harem e le frontiere della colonia. Abbiamo their social systems, territories, spawning behavior, osservato il loro uso di "siti di immersione", siti del loro egg development, egg cannibalism, and interac- habitat sabbioso all'interno del loro territorio in cui sono tions with other species.

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Study Sites: Our mid-1980s studies at Bonaire (12°09’19.49” N, 68°16’46.71” W) and Red Slave, (Fig. 4) were concentrated in two areas, one locally both used in the mid-1980s, and at a new site, named “Red Slave” (12°01’35.29” N, “Double Whammy” (12°08’45.27” N, 68°15’07.73” W) and the other next to the Kral- 68°16’36.81” W), just south of the city pier area endijk (the capital of Bonaire) pier that we called and Triple Whammy. Triple Whammy was no “Triple Whammy” (12°8’58.13” N, 68°16’38.91” longer available as the city pier had become much W). Red Slave, on the southwest tip on Bonaire, busier in the intervening years with more freighters has a series of abandoned slave huts (Fig. 5) on a and particularly more cruise ships. Thus diving in narrow strip of land between the salt evaporation the city pier area without permission was prohibit- ponds still in use and the beach “Rode Pan,” a rec- ed by the harbor master. ommended scuba diving area where we never saw At Red Slave we sometimes encountered rough other divers during our studies in 1985 and 2013. waters and poor visibility (5 m), but during calm In 2013 our studies were conducted at “Mi Cas” seas, it was a fine study site for a large contiguous

Fig. 1. Xyrichtys novacula male (a) with black and white age spots and female (b). Photos by D. C. Shen.

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colony (215 individuals) of rosy razorfish, X. mar- tain Don’s Habitat,” where we had our headquar- tinicensis, and over 25 green razorfish, X. splendens, ters. Triple Whammy was very convenient for mak- in depths from 4.7 to 5.8 m. The X. martinicensis ing dusk dives to observe the spawning of these colony extended over 100 m to the north, but we three species as well as Bothus ocellatus (Konstanti- concentrated our observations on the southern nou & Shen, 1995). This study site, adjacent to the third of the colony, where the fish density was old city pier, had the disadvantage of nearby boats highest. Beyond this colony, another colony began occasionally going overhead, and the presence of further north. After these studies in 1985, Dee snorkelers. It was also cluttered with large pieces of Scarr discovered Triple Whammy (Fig. 6), a site we rusting steel barrels, large wood beams, and dis- named for the decided advantage of having all carded machinery parts. The debris, however, three species of Xyrichtys in one small area. It was made handy markers. The bottom depths ranged offshore of Kralendijk and much closer to “Cap- from the shallowest areas of pearly razorfish, X. no-

Fig. 2. Xyrichtys splendens female (a) and male (b) with the normal mid-body spot in the yellowish patch and a number of black age spots. Photos by D. C. Shen.

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vacula, in 1.8 m to the deepest rosy razorfish, X. inary studies on razorfishes in 1982 and 1983, and martinicensis, at 6.8 m, where a steeper drop-off to survey other areas for razorfishes (1984-86). We began. also made spot checks on spawning activities be- We dived at other sites in Bonaire during prelim- tween the periods of intensive studies.

Fig. 3. Xyrichtys martinicensis female (a) and male (b). Photos by D. C. Shen.

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Fig. 4. Map of Bonaire showing locations of the four study sites where colonies of razorfish were studied: Mi Cas, Triple Whammy, Double Whammy, and Red Slave.

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Fig. 5. Red Slave's slave huts with flamingos flying over the salt ponds. Photo by D. C. Shen.

Fig. 6. Triple Whammy's sandy habitat showing garden eels, Xyrichtys martinicensis, and large wood beam. Photo by D. C. Shen.

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Methods 1985 June 2, 9, 12, Dee, David Batalsky, Dates of Field Studies: 16, 23 Karen Pearson 1984 Jan. 26-29 DS, EC, Dee Scarr, Marty 1986 Jan. 25-Feb. 1 DS, EC, HUB #4 Scheiner, Priscilla Breder, 1986 Feb. 1-10 DS, EC, Dee, Penny, HUB #2 Bob Korth, Stephen Lewis, 1984 Feb. 3, 4, Dee Jan Thibault 12, 18 1986 Mar. 22 Dee 1985 Jan. 15-26 DS, EC, Dee, Penny 1986 Apr. 13 Dee Pemberton, HUB #3 2013 Nov. 12-17 DS 1985 May 6-10, 19 DS, EC, Dee Almost all of our underwater observations were 1985 May 12 Dee made using scuba. Snorkeling was used rarely to (dawn) supplement our surveys with additional measure-

Fig. 7. Xyrichtys martinicensis male on the grid at Triple Whammy with a small spoon-shaped dark spot on its caudal fin which we named "Spoontail." Photo by D. C. Shen.

Fig. 8. Xyrichtys novacula male with irregular black and white age spots. Photo by D. C. Shen.

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ments and observations. Strobe lights were used to Mapping: From 1984 to 1986, we mapped and take still photos with two 35mm cameras: in the measured the territories of all three razorfishes us- mid-1980s a Nikon F-3 with a 105mm lens in a ing different methods and tools such as compasses, Tussey housing, and in 2013 a Canon S95 in a FIX measuring tapes, underwater paper and pencils, housing. A total of 9 volunteer divers spent over and string and stakes. 300 hours making observations, laying grids, and At Mi Cas in 1984 we laid down a 9 m² grid with taking measurements. string on stakes 1 m apart, 3 m to a side. All times were recorded in local Atlantic Time, At Red Slave in 1985 (Fig. 10), since the area four hours behind Greenwich Mean Time. Sunrise sometimes had rough surf, we made a 25 m² grid and sunset times were researched on with 1 m squares, 5 m to a side, and rolled it onto timeanddate.com. Longitude and latitude data a 5+ m PVC pipe. The pipe was taken out to the were researched on Google Earth. X. martinicensis colony and the grid rolled out (Fig. Identification of individual fish: We could often 11) over a high concentration of X. martinicensis identify individual fish by markings, especially on (Fig. 12). The grid was then staked down (Fig. 13). males, and by location within their territories. One At Triple Whammy in 1986 (Fig. 14), we laid X. martinicensis male, which we named “Spoon- some lines for distance, but mostly we measured tail,” (Fig. 7) had a small spoon-shaped, dark spot distances to different human debris markers such on its caudal fin and could be recognized easily as engine blocks, barrels or drums, and large wood- even in the crowded small territories within the en beams to map out the area. We also laid down a rosy colony at Triple Whammy. The X. novacula 30 m by 30 m square with a middle bisecting line males were easy to identify as individuals either over the X. martinicensis colony. through their 0 to 8 irregular spots (Fig. 8), differ- For depth measurements, we used our dive com- ent on each side, or their location in the study site. puters, either Edge or Aladin, and converted the Individual X. splendens males were also identified feet to meters. by their location within the study site. Collecting fertilized eggs: Fertilized eggs were Sexual dimorphism or size and behavior in all collected by a diver swimming up to the cloud of three species made it easy to tell males from fe- gametes, just after release, and drawing water from males. In the late afternoon, females with ovulated this cloud into a plastic 300 ml syringe. These were eggs were conspicuous by their swollen bellies and taken to the laboratory of the CARCO Project, a red swollen area around the cloaca giving the ap- where the eggs were studied and photographed pearance of a small “red balloon” (Figs 9a and b) through a microscope, and kept at 24.5 °C until that deflated as soon as they spawned. hatching.

Fig. 9a. Xyrichtys novacula female with swollen gravid belly. Fig. 9b. Another gravid Xyrichtys novacula female (b) moving Photo by D. C Shen. sand, hunting. Photo by D. C Shen.

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RESULTS bottoms. We never observed X. novacula at the Distribution of the three species of Xyrichtys sandy bottom of coral reef drop-offs found on studied in Bonaire: X. novacula is usually found in most of Bonaire’s west side. However, we did find the shallow (1.8 to 4.9 m) and calmer waters of X. splendens (Fig. 15) and X. martinicensis (Fig. 16) Bonaire. X. novacula was absent at the Red Slave common at depths between 36.6 and 39.6 m at the study site, where the water was often rough, espe- bottom of the drop-off, where the terrain levels off cially in the shallows, with breaking waves on its into sand stretches. unprotected shore and stronger current. At the Both X. splendens and X. martinicensis occur at Triple Whammy site at the city pier, where the wa- Red Slave, Triple Whammy, Mi Cas, and Double ters were calm and protected and with a richer bot- Whammy study sites. X. splendens often curl their tom fauna, the shallow water had a colony of at bodies in a slight “S” curve and camouflage them- least 26 X. novacula. In 1983 we made some pre- selves with a banded color pattern (Fig. 17) while liminary studies in the shallows of two other pro- hugging the bottom especially near some algae, sea tected sandy areas near the pier, one of which was grass, hydroid colony, or small pieces of rubble. Mi Cas, where X. novacula were common. One of Species Sizes: Of the three Caribbean razorfish, our primary contributors, Dee Scarr, who has X. novacula is the largest. The observed males dived in Bonaire for over 30 years, has observed X. reached about 25 cm TL (total length) and females novacula only in shallow, calm water over sandy about 20 cm TL. X. martinicensis are typically

Fig. 10. Detailed map of Red Slave site with territories of Xyrichtys martinicensis and showing a few X. splendens. More X. splendens were scattered around the periphery of the rosy colony. This colony extended NW for over 100 m although the shelf of good habitat sand gradually narrowed.

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female’s sub-territory would be enclosed within the male’s territory. Additionally there was usually more than one female sharing a male’s territory. The largest female sub-territory, that of X. novacula female #1 of male #3, 84 sq. m, is almost as large as the smallest X. novacula male territory, male #8, of 86 sq. m. (Fig. 14). The Red Slave study site is 820 sq. m for the mapped area, and about 3000 sq. m in total. The Triple Whammy study site is 2760 sq. m. The X. martinicensis colony at Red Slave extended for over 100 m to the northwest beyond our mapped area. The Red Slave colony consisted of approx. 215 X. Fig. 11. The authors rolling out a pre-made grid off a PVC martinicensis based on an extrapolation of the aver- pipe at Red Slave in January 1985. Photo by D. Scarr.

Fig. 12. Crowd of Xyrichtys martinicensis. Photo by D. C. Shen.

about 17 cm TL for a male and about 10 cm TL for a female, although we found one stunted group measuring about two thirds that size at Mi Cas. X. splendens are similar in size to X. martinicensis at about 15 cm TL for males and about 10 cm TL for females. Territorial behavior: Male razorfish of all three species of Xyrichtys had distinct territories (Table I). These 100 or more territories (including territories we studied at Mi Cas and Double Whammy) would abut each other without overlapping. Fe- males of X. novacula had sub-territories within their males’ territories. These sub-territories were Fig. 13. Author EC working on grid at Red Slave without fins smaller in size than the males’ territories since each to minimize stirring sand. Photo by D. Scarr.

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Fig. 14. Detailed map of Triple Whammy site with territories of pearly (Xyrichtys novacula), rosy (X. martinicensis), and green (X. splendens) razorfishes. Green territories are much larger than rosy territories despite the fish being about the same size. Observed confrontations between males are marked. Some of the males have no females within their territory. This can be a spark for confrontations. Pearly #7 instigated a border fight with Pearly #2 which turned into a big melee with Pearly #5 and Pearly #6 jumping in. The battle became so heated that some of the fish broke the surface of the water. Females also have confrontations. Two are marked in Pearly #3's territory.

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age density from the mapped area plus visually es- Whammy are shown in Figs. 10 and 14. Females of timated lesser densities for the next 100 m. The X. novacula defended their territories similarly to population number appeared the same in 1985 males, but these behaviors were rarely observed. and in 2013. Our Red Slave mapped area con- We do not know if X. martinicensis females have tained 89 X. martinicensis (43 males with territories well-delineated territories. Females of X. novacula and 46 females) and more than 25 X. splendens. At and X. splendens resided stably within their males’ Triple Whammy, we had 72 X. martinicensis (38 territories, but females of X. martinicensis were not male territories and 44 females), 25 X. splendens (6 always associated with any single male, and passed male territories and 19 female sub-territories), and through territories of several males. The X. mar- 26 X. novacula (8 male territories and 18 female tinicensis male, Spoontail, had a territory where fe- sub-territories). At Double Whammy, we had 7 X. males wandered in and out. On February 5, 1986, martinicensis (3 male territories and 4 females) and Spoontail had two females that remained in his ter- three X. splendens (one male territory and two fe- ritory while three more came and went. On Febru- male sub-territories). At Mi Cas in 2013 there were ary 6, 1986, Spoontail had 13 females in his terri- 37 X. martinicensis (6 male territories and 31 fe- tory during the day, but late in the day, during cop- males), two X. splendens (one male territory and ulation time, he had none and therefore did not one female sub-territory), and three X. novacula mate that day. According to Victor (1987), in X. (one male territory and two female sub-territories). martinicensis, a male may have 35 females in his Males of all three species had clearly delineated ter- territory. ritories as did females of X. novacula and X. splen- When establishing and maintaining territories, dens. However, the territorial situation with female male X. novacula raised their fins and chased away X. martinicensis was unclear. other male X. novacula, male and female X. splen- Males of all three species defended their territo- dens, and male and female X. martinicensis. Con- ries, both interspecifically and intraspecifically at tinuing on from roughly the most to the least dom- territorial boundaries. They would swim quickly, inant, male X. splendens chased other male X. splen- not quite touching, side-by-side along their com- dens, male X. novacula even when the pearly was mon territorial boundary (Fig. 18). The territories larger, and male and female X. martinicensis. Male of the different species both at Red Slave and Triple X. martinicensis chased other male X. martinicensis,

Fig. 15. Author EC at the depth of 39.6 meters holding a just caught Xyrichtys splendens male in a plastic bag. Photo by A. Bassett.

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male and female X. splendens, and female X. novacula. One male X. splendens ignored a chase by a male X. martinicensis. Female X. novacula chased other female X. novacula, female X. splendens, and male X. martinicensis. Female X. splendens chased other female X. splendens. A female X. splendens dis- played erect fins to a female X. novacula when the pearly was over the X. splendens’s dive site. The display was ignored. Female X. martinicensis were not observed chasing anybody. A pecking order, or dominance hierarchy, was observed intraspecifically among all three species, but was least noticeable among female X. martinicensis. In dominance, of Fig. 16. Xyrichtys martinicensis female at the depth of 36.6 course, size mattered. meters. Photo by D. C. Shen. A confrontation between X. novacula male #7 and X. novacula male #2 that was not of the boundary type was observed. Male #7 had no females and appeared to be the instigator. Male #2 had a copulation between skirmishes. A big skirmish developed between four X. novacula males started by #7 and #2, and then joined by #5 and #6, becoming so tu- multuous that some fish broke the surface of the water. The territorial boundaries did not change after this fight. All three species of Xyrichtys had two or more dive sites within their territories. A dive site is a location in the sand into which the fish would habitually return to dive to avoid danger, or sometimes for no Fig. 17. Xyrichtys splendens male with the typical mid-body apparent reason. In all three species, individuals spot, in banded phase, holding in a slight "S" curve. Photo by will conduct dive site maintenance by diving in D. C. Shen. and out of their dive sites a number of times a day, which keeps the dive site soft and fluid (Figs 19a and b). Rubble is moved out of the dive site, sometimes leaving the appearance of a circle of debris if the debris is not moved far, and sometimes moving the debris away many meters (Fig. 20). A re- searcher placed debris in a male X. novacula dive site twice, and the debris was removed each time. X. splendens would more likely have their territories and dive sites in areas with rubble, unlike X. novacula and X. martinicensis. All three species of Xyrichtys use one of their dive sites to retire into for the night (Fig. 21). The Xyrichtys all hover over their chosen night dive site for several minutes before they finally dive in. The relevant data are presented in Table II: Wake-up (first morning emergence from sand) and Retire- ment (last dive into sand for the night) Times for Xyrichtys. Fig. 18. Confrontation run between two male Xyrichtys mar- Sexual behavior: Spawning activity for all three tinicensis along their common territorial boundary. Photo by D. Xyrichtys species occurred from late afternoon to C. Shen. dusk. The spawning depth ranges as well as the

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spawning time ranges and the mean for each es in a row were once observed in the case of X. no- species are shown in Figs 22a and b. For the three vacula. After spawning, the female would typically species, the number of copulations we observed return to feeding or dive site maintenance, whereas during the time of year from November through the male would begin cruising and approaching June for the years 1985, 1986, and 2013 is 155 for other females in his harem. After all the females in X. martinicensis, 57 for X. splendens, and 94 for X. his harem had spawned or were unwilling to novacula. All the eggs are planktonic. spawn, the male would also revert to feeding, or For all three species, pre-mating activity occurred would hover over a dive site. Sometimes a female about one hour prior to the first mating. The male who seemed particularly gravid would seek out a would cruise from female to female in his harem male and display her red balloon to him. This be- within his territory about 5 to 15 cm above the havior would almost always result in a spawning. substrate. In X. novacula and X. martinicensis, if the X. novacula and X. splendens males made upward female’s abdomen was swollen and the anus devel- rushes as if on a spawning rush, but alone. A X. oped a red balloon (Figs. 23a, b and c) then the fe- splendens male also made a series of several loops af- male might sidle up to the male (Fig. 24) and swim ter one such rush. A X. novacula male spawned side-by-side with him. Male X. splendens some- with each of his 7 females in a different order on times encircled a female to check on her readiness each of five separate consecutive nights. A X. mar- to spawn. If the female wasn’t ready, she would tinicensis female interacted with three different swim away from the male. males one evening, spawning with two and display- When the female was ready to spawn, a spawning ing her red balloon to another. X. martinicensis rise of 1 to 3 m above the substrate would occur. males do headstands near females and quiver for Both fish would begin swimming upward side-by- one to two seconds (Fig. 26). A X. novacula male side (Figs 25a, b and c), possibly touching each went into an adjacent male’s territory to chase his other until, at some signal, both fish would sharply own female back into his own territory. Spoontail, reverse course, release their gametes, and dart back a X. martinicensis male mentioned earlier, dived in- towards the substrate. We termed this sharp rever- to the same dive site simultaneously with a female, sal at the top of the spawning rise the “snap,” where and both reemerged immediately, shuddering as a small cloud of milt would usually be seen. The they came half-way out. After they totally emerged, eggs are clear and nearly invisible. Partial or full they resumed feeding. spawning rises without a release of gametes could No spawns were observed at other times of day. occur before a successful spawning. Three such ris- We dived early in the morning when it was still

Fig. 19a. Xyrichtys martinicensis male emerging from one of Fig. 19b. Xyrichtys martinicensis female emerging from one of his dive sites. Photo by D. C. Shen. her dive sites while a male watches. Photo by D. C. Shen.

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pitch black to wait for dawn and observe the razor- ism. However, we never observed X. novacula eat- fish emerge from their sites, but saw no spawns un- ing its own eggs. For male X. martinicensis, there til late afternoon when courtship activities began. were 5 cases of egg nibbling after a copulation out Egg cannibalism: As reported for many other of 155 observed copulations – a cannibalism rate fishes, male razorfishes did exhibit egg cannibal- of about 3% (Fig. 27). For male X. splendens, there

Fig. 20. Xyrichtys novacula female keeping an eye on the photographer as she emerges from her dive site surrounded by rubble. Photo by D. C. Shen.

Fig. 21. Xyrichtys novacula male dives into the sand for the night. Photo by D. C. Shen.

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were 14 cases of egg nibbling out of 57 observed (Fig. 31) while the rest had visible embryos. For X. copulations – a cannibalism rate of about 25%. novacula then, there were some free embryos after Egg development: We collected eggs from two 22 hours. In both species the length of the newly- species of razorfish, X. martinicensis and X. novacu- hatched larvae was just under 2 mm. la, using 300 ml syringes. After a copulation, we Feeding behavior: The three Caribbean razorfish- rushed up to the cloud of gametes and syringed in es exhibit different feeding behaviors. X. novacula as many of the eggs as possible. The eggs were are benthic feeders; we never saw them feeding on brought to the laboratory of the CARCO Project, plankton. Male and female X. novacula sometimes where they hatched at a temperature of 24.5° C. followed feeding goatfishes and occasionally octo- Between 70 and 90 eggs of X. martinicensis were puses and crabs to pick off exposed benthic crea- collected from a spawn at 5:15 pm on February 4, tures, but they mostly foraged on their own. By 1986. Under a microscope, the eggs measured 0.6 contrast, X. martinicensis largely fed in the water to 0.7 mm in diameter and the embryo caps were column on plankton. They never rose more than 2 visible (Fig. 28). By 8:15 pm the next day there m off the bottom. At times the majority of the were several free embryos with the yolk attached colony fed at the same level of the water column, (Fig. 29) about 2.5 cm below the surface, and the sometimes high up and sometimes closer to the rest of the eggs had visible embryos. Many had substrate. X. splendens fed both in the water col- hatched after 27 hours. umn and also off the substrate. Eggs of X. novacula were collected after two cop- Interspecies interactions: All three species of ra- ulations at about 6:15 pm on February 5, 1986. zorfish had many interactions with transient or fel- The eggs were over 0.7 mm in diameter (Fig. 30). low inhabitants of the sand habitat. These interac- By 4:10 pm the next day some eggs had hatched tions can be looked at in four ways according to the

Fig. 22a-b. a. Spawning depth ranges in meters for 3 species of Xyrichtys. b. Spawning time ranges in minutes before sunset for 3 species of Xyrichtys: X. novacula, X. splendens, and X. martinicensis.

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species involved: species that disturb razorfish, species that razorfish chase, species that ignore and are ignored by razorfish, and species that are used by razorfish. The reactions of razorfish to species that disturb them can fit into three categories: “mild,” when the razorfish merely moves away; “strong,” when the razorfish flees or hovers low; and “severe,” when the razorfish dives into the sand. Interspecies interactions also depend on relative sizes of the actors so that different sizes of the same species could fit into different categories. Among the species that disturbed razorfish severe- ly were adult yellowtail snappers, Ocyurus chrysurus that caused both X. splendens and X. martinicensis a to dive into the sand. However, a male X. splendens was seen to chase a 6” yellowtail snapper. A lizardfish, Synodus sp., made X. martinicensis dive, and a barracuda, Sphyraena barracuda, made a female X. splendens dive, but was ignored by a larger X. novacula. Other X. splendens had a strong reaction to barracuda, but not a severe one. A tobaccofish, Ser- ranus tabacarius, caused a X. martinicensis to dive into the sand, but was ignored by other X. martinicensis. Over a foot-long bar jacks, Caranx ruber, caused a strong to severe reaction from male and female X. martinicensis and X. splendens, although X. splendens was also seen chasing a 6” bar jack. Victor (1987) has noted that as a consequence of their open habitat, Xyrichtys martinicensis has 3 times as many strong reactions to predators (16.8/hr) as does the reef-associated bluehead b wrasse, Thalassoma bifasciatum (5.1/hr).

Fig. 23a-c. a. Swollen, gravid Xyrichtys martinicensis female. Fig. 24. Male (right) and female Xyrichtys novacula sidling. b. Swollen, gravid Xyrichtys novacula female. c. Swollen, gravid Photo by D. C. Shen. Xyrichtys splendens female. Photos by D. C. Shen.

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b Fig. 26. Xyrichtys martinicensis male we named Spoontail (note mark on caudal) doing a headstand in front of a female. Both are within the grid. Photo by D. C. Shen.

Fig. 25a-c. a. Xyrichtys martinicensis male (rear) and female in an upward spawning rush. b. Xyrichtys martinicensis male (front) and female in an upward spawning rush. c. Xyrichtys novacula male (right) and female with a swollen, gravid belly in an Fig. 27. Xyrichtys martinicensis male turning to eat eggs after upward spawning rush. Photos by D. C. Shen. spawning snap. Photo by D. C. Shen.

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Many fish were seen chased by razorfish, but only lowfin mojarra, Gerres cinereus (Fig. 32), boga, In- one species, slippery dick, Halichoeres bivittatus, ermia vitata, blue tang, Acanthurus coeruleus, mul- was chased by all three razor species. Fish usually let, Mugil sp., bonefish, Albula vulpes, and scorpion chased by both X. martinicensis and X. novacula in- fish, Scorpaena sp., the last perhaps due to its cam- clude up to 18” parrotfish, Scarus sp., eyed floun- ouflage. X. novacula and X. martinicensis also ig- der, Bothus ocellatus, and peacock flounder, Bothus nored smooth trunkfish, Lactophrys triqueter. Gar- lunatus, although the latter was chased by a male den eels, Nystactichthys halis, were ignored by X. and female X. martinicensis together. Yellowfin mo- martinicensis, but the eels were not found near the jarra, Gerres cinereus, were sometimes chased. X. other two species. X. martinicensis also ignored a martinicensis also chased a sharpnose puffer, Can- permit, Trachinotus falcatus, while X. novacula ig- thigaster rostrata. Both male and female X. novacula nored a 6” bar jack, Caranx ruber, and a 16” spot- chased lizardfish, Synodus sp., and a male chased a ted moray, Gymnothorax moringa. small goby. In addition to the species mentioned, X. novacula had commensal relationships with the during spawning time, X. novacula chased out yellow goatfish, Mulloidichthys martinicus, and pufferfish, Canthigaster sp., goatfish, Mul- spotted goatfish, Pseudopeneus maculatus, with the loidichthys martinicus, and sand octopuses, and a razorfish going alongside the goatfish to capture male and female attacked and bit a bristle worm. benthic creatures it stirred up. A box crab and a Fish mostly ignored by all three species include yel- sand octopus were used similarly (Fig. 33). Once, a

Fig. 28. Xyrichtys martinicensis egg with embryo, about 0.7 mm Fig. 29. Xyrichtys martinicensis larva about 1.8 mm TL. Photo in diameter. Photo by J. Parkyn. by J. Parkyn.

Fig. 30. Xyrichtys novacula egg with embryo, about 0.7 mm in Fig. 31. Xyrichtys novacula larva about 1.8 mm TL. Photo by J. diameter. Photo by J. Parkyn. Parkyn.

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Fig. 32. Xyrichtys novacula male coexisting with yellowfin mojarra, Gerres cinereus. Photo by D. C. Shen.

Fig. 33. Xyrichtys novacula female observing sand octopus. Photo by D. C. Shen.

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spotted snake eel, Ophichthus ophis, with its head Xyrichtys there. Randall (1965) reported that X. no- out of the sand attracted a crowd of 15 X. martini- vacula occurs at depths to “45 fathoms” (82.3 m) censis around it. and has a wide distribution on both sides of the At- lantic Ocean; on the west side it is found from the DISCUSSION Carolinas to Brazil. For any X. novacula living at 45 Distribution of Xyrichtys in Bonaire: Since we fathoms, or, for that matter, any X. martinicensis did not explore any of the windward east side of and X. splendens living at 39 m depth, it is highly Bonaire, where shallow and deep sand stretches unlikely that their spawning times would be any- may harbor Xyrichtys, we do not know if there are thing like the times near the surface since we sus-

Fig. 34a-c. a. Sharply curved Xyrichtys novacula male (right) and female at spawning peak, snapping apart with the male releasing milt. b. Xyrichtys novacula male (left) is heading down after snap while female, still partially gravid, is in her snap turn. The cloud of milt is visible. c. Both male (left) and female Xyrichtys novacula headed down after the snap with the male in the lead, leaving behind a cloud of milt and invisible (clear) eggs. The female is no longer gravid. Photos by D. C. Shen.

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pect that the spawning times are roughly depen- Caribbean Xyrichtys, the males establish and defend dent on ambient light levels. territories. While X. novacula and X. splendens con- Randall (1965) reports that X. splendens populate form to strict haremic behavior as monandric pro- waters of other islands of the Caribbean and range togynous hermaphrodites with females maintain- from southern Florida to Brazil. X. martinicensis, ing territories within one male’s territory, X. mar- which forms the largest colonies, may have the tinicensis in Bonaire did not, contrary to reports of most limited range, from the Yucatán, Bahamas, rosy behavior in Panama (Victor 1987) and Belize Panama (Victor 1987), to Brazil (Randall 1968). (Baird 1988). Victor did observe one spawning out Territorial and Sexual Behavior: In all three of 61 between a non-resident female with a territo-

Fig. 35. Xyrichtys splendens female in banded pattern almost completely emerged from her dive site. Photo by D. C. Shen.

Fig. 36. Xyrichtys martinicensis male removing rubble. Photo by D. C. Shen.

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rial male. In that particular case, the female with the 155 observed copulations were not between a her territorial male crossed the male’s territorial male and a stay-at-home haremic female. We also boundary during a spawning rush and the neigh- have the example of a X. martinicensis female con- boring male chased off the first male and finished sorting with three different males in one night. the spawn. In Belize, Baird observed 77 spawns This non-monandric behavior may also explain where the “females mated with the males whose why at the Red Slave, Triple Whammy, and Dou- territory encompassed their home site.” If female ble Whammy sites males constitute almost half of X. martinicensis have delineated territories, they are the X. martinicensis population: 43 out of 89 not necessarily completely enclosed within a male’s (48%) at Red Slave, 38 out of 82 (46%) at Triple territory. Since many of the Bonaire X. martinicen- Whammy, and 3 out of 7 (43%) at Double sis females didn’t remain within specific males’ ter- Whammy. With females able to wander outside of ritories at Red Slave or Triple Whammy, many of male territories and males not trying to dominate

Fig. 37. Xyrichtys novacula male hunting by scraping sand with his mouth. Photo by D. C. Shen.

Fig. 38. Stunted male (left) and female Xyrichtys martinicensis at Mi Cas. They are about two thirds of normal size. Photo by D. C. Shen.

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Table I. Sizes of male territories at Red Slave and Triple Whammy study sites.

Number Smallest Largest Average in square meters

Red Slave X. martinicensis 43 8 20 11,9

Triple Whammy X. martinicensis 38 2 18 6,4 X. splendens 5 64 207 117,4 X. novacula 8 86 292 163,0

Table II. Wake-up (first morning emergence from sand) and Retirement (last dive into sand for the night) Times for Xyrichtys

Earliest emergence: Latest retirement: Habitat depths minutes after sunrise minutes after sunset in meters

Xyrichtys novacula -5 18 1.8-4.9 Xyrichtys splendens 9 4 2.6-7.0 Xyrichtys martinicensis 20 14 4.3-6.8

and force females to remain within their territories, only months when we were not there for at least the presumed hormonal changes to become males one day to witness a spawn are July, August, Sep- are no longer suppressed. This near one-to-one ra- tember, October, and December. Benjamin Victor, tio is in sharp contrast to the extreme low of 1 to however, has spawn data from December at least 35, and average of 1 to 12.8, or 7%, (later, 1 to for X. martinicensis, albeit in Panama. 10.7, or 8.5%) in Panama (Victor 1987) and 1 to Spawning and retirement times related to depth: 4.5, or 18%, in Belize (Baird 1988). At the Mi Cas We found some correlation between spawning site in 2013, however, there were 6 males and 31 times and retirement times and the depths at females. This colony’s male percentage of 16% is which the three species live. These two behaviors more similar to the Panama and Belize reports and could be related to, and triggered by, the surround- to the other two Xyrichtys species. We have no ex- ing ambient light levels. For easier comparison, the planation for the sharp variation in the ratio of study site depth ranges within which the three males to females of X. martinicensis, but it does not species live are listed in Table II, Wake-up (first appear to be habitat-related. morning emergence from sand) and Retirement Xyrichtys novacula males appear to initiate the (last dive into sand for the night) Times for snap at the peak of rises. The male’s turning down Xyrichtys. For the three species, the depth ranges are and releasing of sperm at the snap probably signals 1.8 to 4.9 m for Xyrichtys novacula, 2.6 to 7.0 m for to the female to release her eggs. This behavior is X. splendens, and 4.3 to 6.8 m for X. martinicensis. too quick for human eyes to notice, but close ex- It is clear that X. novacula, as the shallowest species, amination of several photos of snaps and gamete generally spawns the latest, retires the latest, and releases shows that the male releases his sperm emerges the earliest. The other two species with while he is turning down, and then the female be- overlapping depth ranges also have largely overlap- gins to turn down and releases her eggs after the ping times for spawnings (Figs 22a and b) as well male has turned and started swimming down. Figs as retirement and emergence. 34a, b and c illustrate this well. Sexual Dimorphism: The three Xyrichtys species in It is highly likely that the three species of Bonaire exhibit varying degrees of sexual dimor- Caribbean Xyrichtys spawn all year round. Every phism. Xyrichtys martinicensis has the largest degree time we observed Xyrichtys we saw them mate as of sexual dimorphism with males having a yellowish long as we were there at the right time of day. The operculum and females having a red and white

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striped abdomen. Both also have different body Ultraviolet or Polarized Light: Our theory as to background colors; yellowish-green in the males, how razorfish can know the locations of conspecific rosy-pink in the females. Other than size, Xyrichtys and interspecific dive sites is through ultraviolet or splendens differ by the presence of a mid-body spot polarized light. Other senses such as smell are un- on the males, often on a yellowish patch, and its ab- likely to be sufficient since being up-current would sence in the females. For Xyrichtys novacula, there are leave the razorfish clueless. Some preliminary photo- no obvious body marking differences. Since all the graphic work in 2013 with polarized and UV-only species are protogynous sequential hermaphrodites, filters (in contrast to the common UV filters that usually the males will be larger than the females, block UV wavelengths, UV-only filters allow only which is the case with X. novacula. UV wavelengths through) were inconclusive. This For the older fish of X. splendens and X. novacula, question needs to be answered. generally the males, varying black and white spots Feeding Behavior: The three species of razorfish appear on their bodies as they age. Younger females exhibited territorial aggression despite some degree almost never have any of these markings. The white of resource allocation with X. novacula being pri- spots could be parasites, as is the case with Red Sea marily a benthic feeder (Fig. 37), X. martinicensis be- Xyrichtys (Ilan Perpana, personal communication). ing primarily a planktonic feeder, and X. splendens a Dive Sites: For living in an environment mostly mix of both. When we first dived at Mi Cas, we no- of open sand without readily available refuges from ticed that there were stunted X. martinicensis (Fig. predators, the ability to dive into the sand is a life- 38) close to shore vs. normal-sized X. novacula and saver. However, the dive site debris mounds erro- X. splendens in the same area. We suspect that a lack neously attributed to Xyrichtys novacula probably of flow of planktonic food close to shore is the rea- evolved in the literature from the debris mounds of son for inhibited growth. There are also normal- Malacanthus plumieri (Longley & Hildebrand sized X. martinicensis at Mi Cas, but they are in 1941 and Böhlke & Chaplin 1993). We have nev- deeper water further offshore, with better currents. er seen X. novacula using mounds as dive sites. The The two species which exhibited egg cannibalism, individuals of all three razorfish species maintain X. martinicensis and X. splendens, are also the two out their own multiple dive sites. The maintenance in- of the three species studied here that feed on plank- volves diving in and out of the dive sites several ton. As a benthic feeder, X. novacula was never ob- times a day (Fig. 35) which keeps each dive site’s served engaging in egg cannibalism. However, since sand fluid, and removing debris such as coral X. novacula was about 50% larger than X. martini- chunks and rocks (Fig. 36). censis or X. splendens, plankton or eggs may generally It was easy to push our hands into dive sites com- have been too small to be food for X. novacula. pared to the normal sandy bottom. When we mim- It is not surprising that X. novacula was not found icked the in-and-out behavior of the razorfish by at Red Slave. X. novacula feeds mainly on small ‘diving’ our hands to a depth of 5.5 cm, the spot mollusks in the sand (Randall 1968). The rough maintained a fluid softness to the same depth for waters at Red Slave and the resultant shifting sands over 55 minutes. After an hour, the easily penetrable do not constitute a good habitat for benthic crea- depth became reduced to 3 cm or less. tures so there probably is not enough food there for Generally razorfish only use their own dive sites. any X. novacula. However, Red Slave has plenty of More than once, however, we did observe that a planktonic food to support the large colony of X. male and female X. martinicensis did dive together martinicensis. It is located very near the south point into one dive site. Two female X. martinicensis were of Bonaire, which is usually washed with the wrap- also observed diving into the same dive site. More- around surface currents from the easterly trade over, when we were trying to capture X. martinicensis winds that probably wash in much plankton. This and stressing them, individuals would dive into oth- has not changed in 28 years and the large colony ers’ dive sites and even into plain sand, i.e. not a still exists as before. maintained dive site, thereby taking the risk of Food availability may also to some extent deter- bumping into rocks or hard bottoms. We could tell mine the size of territories of male Xyrichtys. Both it was plain sand because of the difficulty they had X. novacula and X. splendens have proportionately in diving in. How they know one another’s dive sites larger territories relative to their size compared to when there’s no apparent evidence from a human X. martinicensis, and both are more dependent on sensory viewpoint is an unanswered question. benthic creatures in their diet. X. splendens and X.

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martinicensis are similar size fish; yet X. splendens’ CLARK, E. 1983. Sand-diving behavior and territoriality of territories as shown in Table I are more than ten the Red Sea razorfish Xyrichtys pentadactylus. Bulletin of times the size of X. martinicensis’ territories. Eating the Institute of Oceanography and Fisheries, Cairo 9: 225- mostly plankton, X. martinicensis relies more on 242. CLARK, E. & POHLE, J. F. 1992. Monogamy in the tilefish, the currents to provide food than the size of con- Malacanthus latovittatus. National Geographic Research trolled territorial substrate. and Exploration 8 (3): 276-295. LARK, E. & POHLE, M. 1996. Trichonotus halstead, a new ACKNOWLEDGEMENTS sand-diving fish from Papua New Guinea. Environmen- Our study would not have been possible without tal Biology of Fishes 45: 1-11. the contribution of the divers who observed and CLARK, E. & POHLE, M. & RABIN, J. 1991. Spotted sand- recorded the behavior, including the spawning ac- perch dynamics. National Geographic Research and Explo- tivities, of razorfishes in Bonaire: Bob Korth, Pene- ration 7 (2): 138-155. CLARK, E., POHLE, J. F. & SHEN, D.C. 1990. Ecology and lope Pemberton, Karen Pearson, Janet Thibault, population dynamics of garden eels at Râs Mohammed, David Batalsky, Ann McGovern, Marty Scheiner, Red Sea. National Geographic Research and Exploration 6 Priscilla Breder, and Steven Lewis, to all of whom (3): 306-318. we extend our sincere thanks. We are indebted to CLARK, E., RABIN, J. S. & HOLDERMAN, S. 1988. Repro- Roberto Hensen for the use of the CARCO Project ductive behavior and social organization in the sand tile- laboratory, and to Joe Parkyn for taking micropho- fish, Malacanthus plumieri. Environmental Biology of Fish- tographs of eggs and larvae. We also greatly appre- es 22 (4): 273-286. ciate the hospitality of Don Stewart and his staff at CLARK, E. & SHEN, D. C. 1986. Territoriality of Red Sea sand-diving fishes of the genera Xyrichtys and Trichonotus Captain Don’s Habitat; Anita and Bruce Bassett’s (abstract). Uyeno, T., Arai, R., Taniuchi, T. & Matsuura, assistance with airfares and hotel accommodation K. editors: Indo-Pacific Fish Biology: Proceedings of the Sec- costs during Human Underwater Biology (HUB) ond International Conference on Indo-Pacific Fishes, Tokyo. courses given in Bonaire during the time of our 937. studies in 1985 and 1986; and the crew of the Ag- KONSTANTINOU, H. & SHEN, D. C. 1995. The social and gressor fleet for their technical assistance. We are reproductive behavior of the eyed flounder, Bothus ocella- especially grateful to Dee Scarr, not only for her tus, with notes on the spawning of Bothus lunatus and participation in our studies, but also for sharing Bothus ellipticus. Environmental Biology of Fishes 44: 311- 324. her knowledge about razorfish and the dive sites in LONGLEY, W. H. & HILDEBRAND, S. F. 1941. Systematic Bonaire. Dee has had a dive operation in Bonaire catalogue of the fishes of Tortugas, Florida with observa- for over 30 years and made over 6000 dives there. tions on color, habits, and local distribution. Papers from For help in the preparation of this manuscript, we Tortugas Lab 34: 1-331. (Carnegie Inst. Wash. Publ. thank Steven Kogge, Jennifer Salerno, Bianco Piccil- 535). lo, Beverly Rodgerson, Rachel Dreyer, Amelia Bot- NEMTZOV, S. C. 1985. Social control of sex change in the talico, Melody Chen, Tom Hahs, Sue Holderman, Red Sea razorfish Xyrichtys pentadactylus (Teleostei, Labri- Barbara Nykiel-Herbert, Christine Flegler-Balon, dae). Environmental Biology of Fishes 14: 199-211. NEMTZOV, S. C. & CLARK, E. 1994. Intraspecific egg pre- and the Mote Marine Laboratory and its staff. We dation by male razorfishes (Labridae) during broadcast also thank Alexis Balinski of Mote for her help in spawning: filial cannibalism or intra-pair parasitism? Bul- preparing the final figures 4, 10, 14, and 22a and b. letin of Marine Sciences 55: 133-141. National Geographic Society provided the initial RANDALL, J. E. 1965. A review of the razorfish genus seed funds to study sandfishes. Hemipteronotus (Labridae) of the Atlantic Ocean. Copeia 1965 (4): 487-501. REFERENCES RANDALL, J. E. 1968. Caribbean Reef Fishes. T. F. H. Pub- lications, Inc. Neptune City, NJ. 318 pp. BAIRD, T. 1988. Abdominal windows in straight-tailed razorfish, Xyrichtys martinicensis: an unusual female sex char- ROBINS, C. R., BAILEY, R. M., BOND, C. E., BROOKER, J. acter in a polygynous fish. Copeia 1988 (2): 497-499. R., LACHNER, E. A., LEA, R. N. & SCOTT, W. B. 1991. Common and Scientific Names of Fishes from the United BAIRD, T. & LILEY, N. R. 1989. The evolutionary signif- icance of harem polygamy in the sand tilefish, Malacan- States and Canada. Bethesda, MD. 183 pp. thus plumieri: resource or female defense? Animal Behav- SCARR, D. 1986. Sultan of the sand. Scubapro: 51. ior 38 (5): 817-829. VICTOR, B. C. 1987. The mating system of the Caribbean rosy razorfish, Xyrichtys martinicensis. Bulletin of Marine BÖHLKE, J. E. & CHAPLIN, C. C. G. 1993. Fishes of the Ba- hamas and Adjacent Tropical Waters. Second Edition Uni- Science 40 (1): 152-160. versity of Texas Press. Austin, TX. 771pp.

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