ABST RA CT S OF P AP ER S

Albert L. Tester Memorial Symposium 22-23 April 1976

A symposium, intended to be an annual event, was held in honor of Albert L. Tester, who, at the time of his death, was Senior Professor of Zoology at the University of and an active participant in th e affairs of the D epartment of Zoology in teaching formal courses, directing graduate stu dent research, and serving on committees of the D epartment. The faculty and students of the D epart­ ment of Zoology proposed an annual symposium of student research papers as a means of ho noring, in a continuing and active way, Tester's lively enco uragement of student research in a broad range of fields within marine biology. Papers reporting original research on any aspect of marine biology were solicited fro m students of the University of Hawaii.Income from contributions to the Albert L. Tester Memorial Fun d of the University of Hawaii Foun dation was used to pro­ vide two prizes, one for the best paper on fish or fisherie s biology, Tester's own field of special interest, and one for the best paper in any other area. Papers were jud ged by National Science Foundation Distinguished Visiting Scholar Arthur M. Myrberg, Professor, Rosensteil School of Marine and Atmospheric Science, Uni­ versity of Miami, and by D rs. Julie Brock, James Shaklee, and John Stimson from the D epartment of Zoology, Uni versity of Hawaii. Papers were judged on quality, originality, importance of the research reported, and on the quality of the public pres entation . Presentations honored with prizes were those of Paul At kins with D ennis Gorlick, in fish biology, and of Tina Weatherby.

The Social Use of Space in the Hawaiian Ghost , ceratophthalmus

FREDERICK J. L IGHTER

I stud ied the spatial pattern and related social thespati al pattern of the population was rand om. behavior of the Hawaiian , Oiypode Of the remaining threepopulations, two showed ceratophtha/mus, using nearest-neighb or and a pattern of agg regation and one showed a " mean crowding" techniques. Ana lyses were pattern of uniformity. made of 13 different natu ral populations, repre­ Both sex and age differences were present in senting a total of 901 individuals. D ensity burrowing behavior and burrow structure. measurements for these populations range from Juveniles of both sexes constructed two basic 0.48 to 1.01 jrn-; " mean cro wding " esti­ patterns of burrow structu re: mature females mates range from 0.58 to 1.78 other indivi­ and mature nonreproductively active males duals/quadrat/individual. In 10 of the samples, constructed a similar structure and repro­ ductively active males constructed another. Behavioral differences in burrow defense and Abstracts presented in this symposium were written by social interactions were also observed. All crabs graduate students in the University of Hawaii Depart­ ment of Zoology, 2538 The Mall, Honolulu, Hawaii defended their burrows by using one or two 96822. defensive behaviors; a burrow inhabitant either 211 212 PACIFI C SCIENCE, Volume 30, July 1976 assumed a threat posture toward the intruder indicates that one male will prevent another and/or chased the intruder. However, repro­ from constructing a burrow within a radius of ductively active males utilized two additional 71 cm from his own burrow. When total popu­ defensive behaviors. Physical interactions with lation density rose above 0.6 crabs jm-, the male intruders took the form either of pushing with pattern of uniformity was lost, and the pattern folded chelae or of actual combat. became random. Behavioral evidence also Field measurements have demonstrated that indicated that, at population densities above reproductively active male O. ceratophthalmus this level, territorial defense ofa burrow is lost, show a uniform pattern ofspacing among them­ and agonistic behavior occurs in contexts selves when total population density is below which are not relate d to habitation and defense approximately 0.6 crabs jrn-, Behavioral eviden ce ofa burrow.

Light Adaptation Strategies of Hermatypic Corals

R AN D! R EDALJE

Hermatypic corals growing at low light in­ tionjcm- coral tissue increased with a decrease in tensities generally show flattened growth for ms, light. Cyphastrea showed a decrease in chloro­ low calcification rates, and deep pigmentation. phyll-e/cm'' at the lowest light level; L eptoseris These characteristics can be attributed to the did not show this decrease. There was no change physiologica l adaptations of their symbiotic in the numbers of zooxanthellae with light. zooxanthellae. The responses of zooxanthellae Chlorophyll-a/alga l cell increased with a de­ to a range of light intensities can be compared crease in light for both except at the to the light responses of " sun-" and"shade-" lowest light level, where Cyphastrea showed a adapted phytoplankton, where a decrease in decline. These preliminary results indicate that lightintensity generally causes an increase in cell the zooxanthellae of Cyphastrea are adapted to chlorophyll-a content. T wo species of coral, higher light levels than are those of L eptoseris Cypbastrea ocellina, a shallow reef species, and and are unable to increase further their cell Leptoseris incrustans, a deeper reef species, were chlorophyll content at light levels lower than placed in four light treatments (10-, 20-, 40-, 20-percent surfa ce light. L eptoseris zooxan­ 6O-percent surface illumination) to investigate thellae wo uld be expected to . show a similar changes in pigment concentration and in decrease in cell chlorophyll content but at a numbers ofzooxanthellae with changes in light. lower light level than was used in thi s experi ­ For both species, chlorophyll-a concentra- ment.

The Role of Relative Size in Competition for Shelter by Macrobrachium rosenbergii ()

JOHN B RAD PEEBLES

Relative size has been reported to be an were made on the day of simultaneous intro­ important behavioral factor influencing dis­ duction, two, three, and six days after intro­ persal in a number of . This factor duction. Behavioral interactions were recorded was studied by pairing two adult anima ls in only on the day of simultaneous introduction. elliptical tanks (diameter 1 = 137 cm, dia­ Position in space was recorded on all four meter 2 = 75 cm, water depth = 34 em). These observation periods. A total of 360 minutes of tanks offered no avenues ofemigration. A series observation was made for the 15 male pairs. of 15 male pairs was studied. Observations The results ofa partial correlation ofshelter use ·Abstracts of Papers 213

on relative differences in body length, body important roles in determining the outcome of weight, length of right chela, length of left competition for shelter in Macrobrachium rosen­ chela, and carap ace length, indicate tha t relative bergii. differences in chela length and body weig ht play

Anatomy and Functional Morphology of Dermal Collagen Fibers in Sharks

PHILIP J. M OTTA

The dermis of sharks consists in part of a the majority of the angles lying from 50° to 70°. highly ordered array of collagen fibers . These Fibers lying within the latter range are believed fibers form layers of alternately oriented sheets to undergo minimum change in length during that runin helical paths aro und the shark's body. contraction and resultant thickening of the The fiber paths are oriented from dorsocranial lateral muscles that accompanies swimming; to ventrocaudal and from ventrocranial to therefore, the fibers imp ose minimum restric­ dorsocaudal. tion on the swimming shark . As many as 46 layers of thes e strong, only The fiber layers are believed to serve at least partly extensible collagen fibers are found in in part a mechanically protecti ve function and as adult Ging(ymostoma cirratum. In all sharks a firm and evenly dist ributed anchorage for the examined, these layers were closely and firmly body musculature. bound together by cross-over collagen fibrils Single layers of the more superficial collagen that joined alternate layers. fibers overlie the ceratotrichia of the caudal fin, The angle that the fibers make to the longi­ lending support to the flexible ceratotrichia and tudinal axis of the shark varies from 90° in the probably giving the fins additional support and occipital region to almost 0° in the caudal fin, rigidity.

Fecundity as a Measure of Reproductive Investment in Marine Fishes

S TEPHEN R AL STO N

Fish fecundity data are most frequently fitted widely between species and may reflect dif­ to a power function where fecundity = a size fl. feren ces in the adaptation of species to their Given some information about total energy environment. intake, we see that estimates of the exponent(fl) Estimates offl allow us to infer that allocation can provide insights into th e manner in which of energy toward reproduction may increase available energy is allocated to growth, repro­ geo metrically with the size and weight of the ductive, and maintenance processes. individual. A simple model is presented that Fecundity exponents and their 9S-percent explores alternative ways in which these confidence intervals have been determined for a increases may arise in Chaetodon miliaris, a variety of H awaiian fishes. Estimates vary Hawaiian endemic butterflyfish.

Comparative Ultrastructure of Intestinal Epithelia from a Freshwater Prawn and a Desert Scorpion

W ILLIAM]. C OOKE

The intestinal epithelia. of th e freshwater the ultrastructural level. The midg ut cells of the prawn Macrobracbito» rosenbergii and the desert prawnare similar in their shape and organization scorpion Hadrnrus arizonensis are compared on to generalized transporting epithelia. They are 214 PA CIFIC SCIENCE, Volume 30, July 1976 long columnarcells having manylong microvilli in some states of dehydration, the intestine is projecting into the lumen, a central or basal filled with precipitated guanine crystals. nucleus, extensive basal smooth end oplasmic The gut epithelial cells of th e scorpion thus reticulum, and a somewhat convoluted basal bear features (extensive basal infolding, local­ membrane. They are joined apically by well­ ization ofmit ochondria) usu ally associated with developed septate desmosornes and occluding active ion /water resorption organs ( zonules. Many, ifno t most, of the mitochondria gills and segmental organ tubules), which may are located in the apical end of th e cell, belo w maintain a standi ng gradient in the basal region, the brush border. Epithelial cells from the as well as canaliculi and sparse micro villi typical scorpion have short spars e microvilli projecting of secretory cells in a rigorous environment into thelumen, longer microvilli being restricted (stomach HCl secretory cells). The cells of the to clefts between cells and canaliculi extending prawn gut display features (long microvilli, into the cells. The nucl ei are located at th e apical mitochondria, extensive end oplasmic extreme basal end of the cell, where an exten­ reticulum and Golgi bodies) of cells that are sively infolded basal membrane provides con­ involved with absorption and protein synthesis. siderable amplification of cell surface area. The These morphological results tend to confirm th e majority of mitoch ondria are located basally in observed water flux and amino acid up take these infoldings, with others present aro un d the properties th at have been ascribed these cells canaliculi. T he scorpion hindgut is a major site from in vitro experiments. of water abso rption in these desert , and,

Effects of the Cleaning Behavior of Labroides dimidiatus on Fish Ectoparasites

P AUL D. ATKINS AND D ENNIS L. G ORLICK

The idea that cleaning symbiosis is importa nt data indicate that L. dimidiatus preys predomi­ for the control of ectoparasitism in marin e fishes nantl y on larger Dissonus sp. individuals, effec­ is a controversial hypothesis largely lacking tively reducing their abundance on P. uaiaii. empirical supp ort. We investigated this pro blem There were also indications of an increased at Enewetak Atoll by collecting samples of th e abun dance of smaller individuals on reefs with copepod ectoparasite Dissonus sp. found on th e cleaners, which may explain wh y no differenc e host fish Pomacentrus vaiuli. Pomacentrus vaiuli in total numbers of ectoparasites per host was were collected from three types of small lagoon observed. The net effect ofth e cleanin g behavior patch reefs: (1) reefs with L. dimidiatus, (2) reefs of L. dimidiatus is to reduce the total biomass of without L. dimidiatus, and (3) a reef from which ectoparasites infecting host fish. all L. dimidiatus had been removed. Potential benefit to the host in this cleanin g The number of ectoparasites infecting indi­ symbiosis and interpretation of these results in vidual P. vaiuli was low on all reefs and there light of thework ofprevious authorsis discussed. were no significant differences among the reefs This research was supported by E nergy in the mean nu mber of ectoparasites per fish. Research and D evelopment Administration H owever, th ere were clear differences in the size contract AT (26-1)-628. composition of the copepod populations. T he Abstracts of Papers 215

The Use of Beach Crab Erythrophores as a Rapid Assay for Neurosecretion

TINA M. WEATHERBY

Red chromatophores of the common tropical scored. The average change of stage at 2 min beach crab Oiypode iaeuis are unusu al in their when plottedagainst the log ofconcentration of rapidity of response to erythrophore-concen­ sinus gland extracts (one sinus gland/0.6 m) 2 trating hormone. T hey are capable of changing H 20 ), is linear for dilutions of 1 x 10- to from a fully expand ed, stellate condition (stage 5) 1 X 10- 4• This assay meth od lends itself well to to a completely punctate state (stage 1) in less electrophysiological studies of isolated sinus than 2 min. This change is brought about by a glands. Applying to the sinus gland 100 stimuli neurohormone released by the sinus gland, a in trains of5 per sec every 10 sec releases enough neurohemal organ located in th e eyestalks of hormone in 0.1 ml solution to allow ready crustaceans that consists ofa dense aggregation assay. The meropodite chromatophores and of nerve terminals. The erythrophore response their responses to the hormone are relatively forms the basis of a highly sensitive, semi­ insensitive to ionic altera tions of the saline ; this quantitative bioassay for studies of neuro­ has proved invaluable in studies of low (to 0) secretory release from the sinus glands of a calcium and high (up to 10 x) potassium solu­ variety of crustacean species. The meropodite tions on horm one release by sinus glands. T hus, segment of a walking leg from small (2.G-2.5 em this bioassay method is one of the most con­ carapace width) animals is isolated and perfused venient yet devised for studies of neurosecretory with a physiological saline. Erythrophores be­ systems. come stellate within 20 min . For assay, the This research was supp orted in part by perfusionis stopped and the sample introduced; National Science Foundation grant BMS72­ minimum required volume is 0.1 ml. The stage 02421Al and by the University of Hawaii ofexpansion offive individual eryt hrophores is Foundation.

Food Habits of Two Sympatric Batfishes (Ogcocephalidae) Offshore of Cape Canaveral, Florida

G ARY WINANS

The stomach contents of tw o sympatric bat­ correlation between the standard length of fishes (Ogcocephalidae) were analyzed. Ogco­ Ogcocephalus sp. and the size of prey items . cephalus sp. and Halieuticbtbys aculeatus are Ogcocephalus sp. consumed principally scallops demersal carnivores with noncrushing dentition during cool water months (D ecember through and an illicium or luring apparatus justabove the June) and gastropods during the warm water mouth. Samples containing both species were months (July through N ovemb er). The diet of obtained 35 km offshore of Cape Canaveral, Halieutichthys aculeatus did not vary noticeably Florida, from April to December 1974. T he during the study period. Behavioral differences standard length of Ogcocephalus sp. range d fro m were noted between indi viduals of the two 85 to 150 mm (mean, 124 mm), whereas speci­ species that were being held in aquaria. Whereas mens of Halieutichtf:!ys amleatlis ranged from 33 H. aculeatus was sedentary and would flip gravel to 92 mm (mean, 70 mm). Ogcocephalus sp. onto its back with its pectoral fins, Ogcocephalus consumed primarily gastropo ds and pelecypods sp. was more active and would slowly roam the and H. aculeatus consumedprimarilypolychaetes. bottom of the aquarium. Thus, the dietary and Neither species exhibited a qualitative change in behavioral differences reported here suggest that diet with an increase in size or with respect to systematic differences may exist in the foraging sex. However, there was a significant positive methods of these two sympatric batfishes. 216 PACIFIC SCIENC E, Volum e 30, July 1976

Studies on the Coral-Boring Polychaete Spirobranchus giganteus (Serpulidae) in Hawaii

J ANETW HITE

The tubiculous polychaete Spirobranchus gi­ water on a diet ofChlorella. Eight-day-old larvae ganteus inhabits living coral throughout the have well-developed eye spots and telotroch, tropics. In Hawaii this wo rm occurs in the and th e digestive system is clearly delineated by coral Porites lobata. Opercular and setal charac­ the presence ofingested Chlorella. Fou rteen-day­ teristics indicate th at the sub species in Hawaiian old larvae have developed three setigers that waters is S. giganteus cornitulatus, also recorded bear simple setae. Settlement and metamor­ from the Red Sea, western Pacific, and eastern phosis begin at approximately the 17th day. Australia. Prior to settlement the larvae crawl on th e In situ S. giganteus is easily recognized by a substrate, trailing a mucuslike material that raised ridge of coral that extends po steriorly appears to be produced posteriorly. At this fro m the tube aperture. Sections cut throug h stage the collar is clearly visible and the pos t­ worm burro wsin the coral show that, anteriorly, trochal region is elongated and orange-brown in the tube lies just beneath the coral surface, while color. Transparent tubes are produced by the posteriorly the tube penetrates at an angle into metamorphosed individuals. None of the larvae the coral skeleton. The posterior end of the survived past this ·stage . Various substrates, burro w is not tapered to a point, indicating that including coral fragments, mollusc shells, and the worm may be laying down tube over the coralline algae, were provided for settlement; surface of the coral while at the same time however, in every case the larvae settled on the extending the burro w into th e coral, but this plastic culture dishes. has not been proven. This research was supported by Sea Grant The larvae of S. giganteus, which are typical Program, University of Hawaii, 1975. trochophores, survived 23 days in filtered sea-

Nesting Rhythmicity in the Damselfish Plectroglyphidodon johnstonianus (Perciformes, Pomacentridae) in Hawaii

CRAI G D. MACDONALD

The nesting frequency of a total of70 nestin g are responsible for the observed rhythmicity. males of the damselfish Plectrog(yphidodonj ohn­ A lunar component does not exist. It is antici­ stonianus was continuously reco rded at 6-day pated that several differentially phased, inter­ intervals for 19 months in Kaneohe Bay, Oahu, related environmental cues will be found to be Hawaii. Two peaks in th e spawning frequency responsible for the entrainment of this rhythm of nesting males occur ann ually from September in adults. T here is also some agre emen t between through October and again from February periods ofpeak production ofdamselfish larvae through May. Time series analyses by periodo­ and the perio dic maximum den sities of micro­ gram indicated that threeoscillatorycomponents copepods upon whi ch the larvae presumably ofapp roximately 120-,1 80-, and 360-day periods prey. Abstracts of Papers 217

Mechanism of Thermoregulatory Heat Production during Cold Acclimation in the Rat: Role of Active Na+ Transport

D UANE L. GUERN SEY

I tested th e hypothesis that active Na'" creased Q02Produced during cold acclimation: transport is stimulated during cold acclimation stimulation of active Naf transport accounted to provide increased calorigenesis by measuring for 84 percent of the total increase in Q02 in th e Q0 2- and N af-independent respiration of diaphragm , 71 pe rcent in the pectoral muscle, skeletal muscle(pectoral muscle and diaphragm), 83 percent in the liver, and 64 percent in the liver, and kidney slices from cold expo sed and kidney. It is suggested th at the calorigenic control rats. The time course and patte rn of process of active N af tr ansport via th e mem­ QO activation was different for th e three tissu es; brane Na+ pump is an important source of 2 when th eir responses were combined, the net thermoregul atory heat production during cold response was consistent with the pattern of non­ acclimation in the rat. shiv ering th ermogenesis. In all tissues studied, This research was supported by National th e increased energy utilization by the Na f pump Institutes of H ealth research grant SR01 was responsible for the major fraction of in- AM17336-02.