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1.
Coral spawning in Western Australia (WA) occurs predominantly in the austral autumn in contrast to the Great Barrier Reef
(GBR) on Australia’s east coast where most spawning occurs in spring. Recent work, however, suggests a second spawning period
in northern WA with at least 16 Acropora spp spawning in spring or early summer. This discovery has initiated a re-examination of reproductive seasonality in northern
WA, particularly on inshore reefs adjacent to large development projects, such as the site of this study in Mermaid Sound,
in the Dampier Archipelago. Three locally abundant taxa, Porites spp, Pavona decussata and Turbinaria mesenterina were sampled monthly from September 2006 to May 2007 to determine sexuality, the mode of reproduction and the time of gamete
maturity. All three taxa were gonochoric broadcast spawners. Porites spp. colonies were mature in November and December, P. decussata in March and April. In contrast, most colonies of T. mesenterina contained mature gametes for up to 5 months beginning in November, suggesting either individuals are releasing gametes on
multiple occasions, or they retain mature gametes for more than 1 month. Field surveys to determine the reproductive status
of the remaining coral assemblage were conducted prior to the full moon in October 2006 and March 2007. Only four species
contained mature gametes in October 2006. In contrast, 55 species contained mature gametes in March 2007. We conclude that
the major spawning season of corals on shallow-inshore reefs in the Dampier Archipelago is autumn, although taxa that spawn
in spring and summer include Porites spp., Acropora spp. and possibly T. mesenterina that are numerically dominant at many of these sites. Consequently, management initiatives to limit the exposure of coral
spawn to stressors associated with coastal development may be required in up to five months per year. 相似文献
2.
Reproductive success among clonal taxa is often portrayed as a simple function of clone size, but reproduction in Pseudoplexaura porosa (Houtuyn), a common Caribbean gorgonian, reflects a more complex relationship between size and gamete production. Tagged
colonies were sampled at two reefs in the San Blas Islands, Panama during the 1995 spawning season to determine the colony
size at first reproduction, size-dependent polyp fecundities, and whole colony gonad production, and to follow the gametogenic
cycle. Additional data were obtained during non-spawning months in 1984 and 1985. Of 120 colonies ranging in height from 20
to 250 cm, only colonies taller than 50 cm were reproductive. An average of 4.33 oocytes polyp−1, 560 to 800 μm in diameter, were released during monthly synchronous spawning events from June to September. Oocytes released
each month developed from a group of intermediate size oocytes present at the end of the preceding month. Almost all oocytes
>560 μm were released during each spawning event. Spermatogenesis was a shorter process than oogenesis. During each spawning
month, mature spermaries developed from a group of <125 μm spermaries. Virtually all spermaries >190 μm were released each
month, and most of the spermary volume in mature male polyps was generated anew each month of spawning. Among reproductive
colonies, polyp fecundity increased with colony height from 50 to 200 cm. Per capita fecundity of >200 cm tall female colonies
was lower than for 150 to 200 cm colonies, but whole colony fecundity of large colonies was greater due to the exponential
increase in the number of polyps that occurs with increasing colony height. In male colonies, both polyp and colony reproductive
output increased with colony height. The large amounts of sperm produced by large male colonies probably contributes to the
high rates of in situ fertilization observed in P. porosa. Differences in fecundity as a function of colony size and sex suggest differences in some combination of the cost of reproduction
and/or allocation of resources to reproduction.
Received: 9 September 1998 / Accepted: 7 June 1999 相似文献
3.
P. W. Glynn N. J. Gassman C. M. Eakin J. Cortes D. B. Smith H. M. Guzman 《Marine Biology》1991,109(3):355-368
Reproductive ecology of two major reef-building corals in the eastern Pacific [Pocillopora damicornis (Linnaeus) andPocillopora elegans Dana] was investigated between 1984 and 1990 in Costa Rica, Panama (Gulf of Chiriqui and Gulf of Panama), and the Galapagos Islands (Ecuador) following the 1982–83 El Niño disturbance. Mature spermatocytes and oocytes were found in both species and were usually present in the same polyp in nearly equal ratios. Numerous zooxanthellae were observed in mature, unfertilized oocytes. Although spawning in field populations was not observed, it is likely that both pocilloporids are simultaneous hermaphroditic spawners, as evidenced by the disappearance of mature gametes after full moon. This is in contrast with most known pocilloporid corals that brood and release planula larvae. Corals were reproductively most active in the thermally stable environments of Costa Rica and the Gulf of Chiriqui (Panama) where 32 to 90% of all colonies contained gametes. In the moderately varying thermal conditions in the Galapagos Islands, 16 to 40% of colonies contained gametes, and in the pronounced seasonal upwelling environment of the Pearl Islands (Panama) only 6 to 18% of colonies contained gametes. Year-round reproduction occurred in Costa Rica and the Gulf of Chiriqui, whereas reproduction was confined to warm periods in the seasonally varying environments of the Galapagos Islands and the Gulf of Panama. Pocilloporid corals in Costa Rica and the Gulf of Chiriqui demonstrated lunar spawning activity, with mature gametes present a few days before and after full moon. Some limited spawning may have occurred also at new moon. While frequent gamete maturation has been demonstrated in this study, the relatively low rates of larval recruitment occurring on eastern Pacific coral reefs disturbed by the 1982–83 El Niño suggest that the recovery of important frame-building corals could be greatly prolonged. 相似文献
4.
Anthelia glauca Lamarck, 1816 is a gonochoric, external-brooding soft coral found in KwaZulu-Natal. It is reproductively active in the summer
months. The development of gametes produced in late summer is arrested in winter. Several stages of gametes are found at the
base of the polyps, and female polyps produce several cycles of larvae over an extended breeding period of 4 to 5 months.
Larvae are brooded in a unique pharyngeal brooding pouch not yet described in other coral species. The brood pouch consists
of an expansion of the pharynx with constrictions proximal and distal to the embryos and larvae. Our data suggest that egg
transfer and fertilization occur at full moon and the mature larvae are released after new moon. Zooxanthellae are absent
in A. glauca oocytes, but zooxanthella infestation commences at the immature larval stage.
Received: 15 July 1997 / Accepted: 12 March 1998 相似文献
5.
S. Ward 《Marine Biology》1992,112(4):641-646
The reproductive activity of 88 colonies of Pocillopora damicornis at Rottnest Island, Western Australia, was examined over 12 mo (20 August 1988 to 20 August 1989). Larvae were found close to the three new moons of February, March and April, 1989, but in large numbers only during March; 67% of all corals produced larvae. There was no obvious connection between gametogenesis and the production of brooded larvae; however, those corals which did not produce, larvae also did not produce ova but did produce, sperm, and must be considered male colonies. All colonies which produced ova went on to produce planulae. Spermatogenesis occurred throughout the year, but oogenesis occurred between September 1988 and April 1989. Dramatic declines in the percentage of polyps containing eggs and sperm occurred in early February and early April 1989. On these dates the amount of lipid in the tissue of the corals decreased, which suggests that the decline in the percentage of polyps with sperm and eggs was not due to the gametes being resorbed by the polyps. Therefore, P. damicornis at Rottnest Island appears to be both a brooder and a broadcaster with asexual reproduction through brooded larvae and sexual reproduction through spawning of gametes. This accounts for earlier evidence in the literature that some input from sexual reproduction had been occurring in the populations of P. damicornis at Rottnest Island. There is no direct evidence for spawning, as broadcasting of gametes has not been observed, but the indirect evidence provides a strong argument for the existence of this dual reproduction. 相似文献
6.
The reproductive biology of Antipathes fiordensis Grange, a species endemic to south-western New Zealand, was followed from April 1994 to May 1995. Ten colonies were individually
tagged in Doubtful Sound and sampled on a monthly basis in order to determine their reproductive activity. The fecundity of
each of the five tagged female colonies was determined by estimating the total number of polyps per colony from photographs
of each colony and by planimetry, the proportion of gravid polyps per colony, and the mean number of oocytes per gravid polyp.
In addition, 56 colonies were sampled in March 1995 to estimate the sex ratio, height at sexual maturity, and mean sizes of
females and males. A. fiordensis was found to be a dioecious species which, in the absence of gonads in the polyps, has no obvious external morphological
differences between the sexes. Broadcast spawning of gametes is the likely mode of reproduction. Gametogenesis began in November
1994 and was highly synchronous within and between colonies, with spawning occurring in March 1995. The sex ratio in adults
was 1:1. Colonies reached sexual maturity between the heights of 70 and 105 cm which, based on existing estimates of growth
rate, corresponds to a minimum age for sexual maturity of about 31 yr. The largest oocytes measured ranged from 100 to 140 μm
in size. Female colonies produced between 1.3 and 16.9 million oocytes, with the larger colonies dominating the reproductive
output of the population.
Received: 23 June 1997 / Accepted: 1 August 1997 相似文献
7.
The mode of reproduction in Pocillopora verrucosa Ellis and Solander, 1786 varies between geographically isolated regions. This scleractinian coral is common along the KwaZulu-Natal
coast, and its reproductive mode and period of reproduction were assessed using histological preparations. The study was undertaken
from 1992 to 1994 and showed that P. verrucosa is a simultaneous hermaphrodite and broadcast spawner in KwaZulu-Natal. Gametogenesis occurs from October to January, with
the gametes maturing simultaneously so that spawning can be synchronised at new moon in January (mid-summer). Zooxanthellae
are present in the mature oocytes.
Received: 10 September 1997 / Accepted: 6 July 1998 相似文献
8.
Reproduction and recruitment of scleractinian corals in a high-latitude coral community, Amakusa, southwestern Japan 总被引:1,自引:0,他引:1
Reproduction and recruitment in high-latitude coral populations in Japan have been little studied. A comprehensive study of the reproduction and early life history was conducted on nine common scleractinian coral species in Amakusa, southwestern Japan (32°N) from 2001 to 2003 including; (1) fecundity (the proportion of colonies with mature eggs), (2) timing and synchrony of spawning, (3) initial larval settlement pattern, (4) recruitment, (5) post-settlement mortality. The fecundity was high (76.7–100%) in six of seven species examined in 2002 and 2003. Annual spawning of the seven species occurred from mid July to August in 2001–2003, when seawater temperature was at the annual maximum. Spawning was highly synchronised among conspecific colonies and species in 2002 and 2003, with five species spawning five to nine nights after the full moon and another two spawning around the new moon. Temporal patterns of larval settlement of three spawning species during the first 10 days after spawning were similar to those of other spawning species from low latitudes. The number of scleractinian recruits on settlement plates, deployed from July to October (the major recruitment period at the study site), was low (2 recruits/m2) for the three consecutive years. Post-settlement mortality of 1–1.5 month old spat of five species ranged between 88 and 100% over 3–10 months in the field, similar to the values reported for both high and low latitude species (>94–99%). Among the key stages examined, the low recruitment rate may be the most important step in limiting successful reproduction and recruitment of these high-latitude scleractinian populations. The low recruitment rate may be attributable to (1) the reduced influx of larval supply from other coral populations, which are smaller and more isolated at high-latitudes and (2) the longer precompetent larval phase of broadcast-spawning corals which results in an increased chance of larvae being dispersed away from parent populations. 相似文献
9.
Although the fitness consequences of herbivory on terrestrial plants have been extensively studied, considerably less is known
about how partial predation impacts the fitness of clonal marine organisms. The trophic role of Caribbean parrotfish on coral
reefs is complex: while these fish are important herbivores, as corallivores (consumers of live coral tissue), they selectively
graze specific species and colonies of reef-building corals. Though the benefits of parrotfish herbivory for reef resilience
and conservation are well documented, the negative consequences of parrotfish grazing for coral reproductive fitness have
not been previously determined. We examined recently grazed colonies of Montastraea annularis corals to determine whether grazing was positively associated with coral reproductive effort. We measured gonad number, egg
number and size, and proportional reproductive allocation for grazed and intact coral colonies 2–5 days prior to their annual
spawning time. We found that parrotfish selectively grazed coral polyps with high total reproductive effort (number of gonads),
providing the first evidence that parrotfish selectively target specific tissue areas within a single coral colony. The removal
of polyps with high reproductive effort has direct adverse affects on coral fitness, with additional indirect implications
for colony growth and survival. We conclude that chronic grazing by parrotfishes has negative fitness consequences for reef-building
corals, and by extension, reef ecosystems. 相似文献
10.
The present study examined the mode and timing of reproduction of poorly understood deep-water octocorals and the environmental
factors that may influence their reproductive patterns. Data on reproductive characteristics of the octocoral Drifa glomerata (Alcyonacea: Nephtheidae) collected between 2004 and 2007 at ca. 100–330 m depth off Newfoundland and Labrador (eastern Canada)
were compared among years, months and depth ranges. No male gonad was ever observed during the study. The ratio of fertile
colonies possessing large pinkish polyps with oocytes/planulae was >50% throughout the year. The number of brooded planula
larvae within a single fertile polyp varied between 1 and 10 for a total of approximately 40–3,000 in a whole colony. The
size of oocytes and/or planulae was consistently greater in the polyps than in the branchlets, indicating that the development
pathway of oocytes to planulae is from the branchlets to the polyps. Although larval production seemed to persist year round,
the onset of major planulation events occurred in December–January of two consecutive years, when large mature planulae were
released in correlation with the first increase of photoperiod and maximum temperature at 150 m. A second peak in planulation
between April and early June followed the phytoplankton bloom. Seasonal trends were more apparent in colonies from <200 m,
and the planula index varied among sampling depths and years. Larval release in a live colony under laboratory conditions
occurred between January and June 2008, closely following predictions based on field samples. 相似文献
11.
Sexual reproduction of the reef-building coral Montastreacavernosa was studied in the Santa Marta area, Caribbean coast of Colombia, from October 1990 to October 1991. The area is subjected
to a seasonal upwelling–outwelling regime. From microscopical analysis of tissue sections sampled each lunar month around
the full moon, it was confirmed that this is a gonochoric, broadcasting species, with a single gametogenic cycle per year,
and a 1:1 sex ratio. Oogenesis began a few weeks after spawning, and extended for 11 mo. The onset of spermatogenesis occurred
just before the full moon of June, later than at other localities where sea-water temperatures during the first half of the
year are not as low. The amount of reproductive tissue strongly increased in both sexes after July, in association with an
increase in sea-water temperature and a decrease in photoperiod. The gonad index of fully mature female colonies was about
four times lower than at other localities, perhaps due to the stressful seasonal regime. The male gonad index was lower than
that of the female, indicating sex-related differences in the rates of biomass allocation to reproduction. As in other Caribbean
localities, spawning occurred after the full moons of August and September. However, there was some evidence of a third spawning
episode after the full moon of October, possibly associated with a delay in the occurrence of maximum sea-water temperatures
in near-equatorial localities compared to higher latitudes. The probability of cross-fertilization in this species with a
gonochoric breeding system and a broadcasting mode of reproduction is favored by its balanced sex ratio, its usually high
within-reef zone abundance, and by localized and repeated spawning episodes, synchronized by lunar phase.
Received: 19 April 1996 / Accepted: 24 September 1996 相似文献
12.
The ascidian Styela clava, native to the north-west Pacific, is an invasive species affecting New Zealand’s marine ecosystems, biodiversity and aquaculture
operations. To provide detailed information on the reproductive biology of S. clava in New Zealand for post-border biosecurity management, long-term seasonal patterns of gametogenesis were determined from
May 2006 to May 2008 in Auckland’s Waitemata Harbour (36°49′20″S, 174°45′85″E). Of particular interest was whether the critical
15°C threshold spawning temperature for reproduction observed in the Northern Hemisphere applied here to the first Southern
Hemisphere study. S. clava gametogenesis followed a regular seasonal cycle with ripe gametes appearing as early as September and persisting to June;
this time frame corresponds to the period when sea surface temperatures in the region first reach 15°C and with spawning occurring
mainly during late summer to early autumn. From photoperiod manipulation, it was determined that spawning occurred at approximately
18:20. The extended reproductive period and a short generation time in the Waitemata Harbour provides a lengthy opportunity
for S. clava to spread. Findings are discussed in relation to S. clava’s post-border management. 相似文献
13.
A mass synchronous spawning of the sea urchin Evechinus chloroticus (Valenciennes) was observed in situ in Doubtful Sound, a large New Zealand fiord. Spawning occurred between 17:30 hrs and
18:30 hrs on 27 January 1994 and coincided with a full moon, spring tides and a period of decreasing sea temperatures. During
spawning, the sea urchins formed a dense spawning aggregation of both sexes, with >90% of the urchins observed spawning at
the time. Spawned gametes clouded the water column, and some were eaten by small labrid fish species. The spawning, which
may have been as widespread as 40 km, marked a 42 to 50% decrease in gonad indices and resulted in a widespread, dense cohort
of E. chloroticus larvae within the fiord.
Received: 25 September 1997 / Accepted: 6 March 1998 相似文献
14.
15.
The current contribution deals with the reproductive biology of a genus endemic to Brazil –Mussismilia Ortmann, 1890 – including all three species of the genus: M. braziliensis (Verrill, 1868), M. hartti (Verrill, 1868), and M. hispida (Verrill, 1902), which occur sympatrically in the studied area, the Abrolhos Reef Complex, Brazil. Sexuality patterns, modes
of reproduction, synchrony and spawning periods are reported, and were determined by histological examination of material.
All three species started to develop female and male gametes over different periods in the same breeding season. The three
species are probably broadcast spawners, since no embryos or planulae were observed in any species at any given time of the
year. Each reproductive cycle lasted approximately 11 months. Oogenesis and spermatogenesis started in different periods,
with spermaries appearing in approximately the eighth month of ovary development and lasting about 3 months. Reproductive
cycles were annual. Spawning probably occurred in consecutive months in each species. In M. braziliensis, spawning presumably happened between March and the middle of May in 1996 and 1997. Evidence suggested that spawning events
of M. hispida took place between the end of April and mid-June. M. hartti may have spawned between September and November. The data presented here suggested that all studied species have at least
one exclusive spawning period, asynchronically with the others. A possible exception may be the simultaneous (or close) spawnings
of M. braziliensis and M. hispida in May. It is suggested that asynchrony in spawning periods among species may reduce the chance of hybridization, gamete
waste and the competition for settlement surfaces. The occurrence of extended spawning periods for each species may also reduce
the risks of reproductive failure, due to temporary adverse conditions.
Received: 8 December 1998 / Accepted: 15 July 1999 相似文献
16.
C. C. Wallace 《Marine Biology》1985,88(3):217-233
Multispecies assemblages of the coral genus Acropora occur commonly throughout the Indo-Pacific Ocean. Nine species from such an assemblage comprising 41 species of Acropora, at Big Broadhurst Reef on the Great Barrier Reef, were studied during 1981–1983. Similarities and differences in reproductive modes and timing, oocyte dimensions and fecundity, recruitment by larvae and by fragments, and mortality were recorded. All species had an annual gametogenic cycle, were simultaneous hermaphrodites, and had the same arrangement of gonads in polyps. In six species, most colonies released gametes on the same night of the year, in early summer, during a mass spawning event involving many coral genera. A seventh species had colonies spawning at this as well as other times of the year. Another species spawned in late summer, and gametes were not observed to mature in the last species. Eggs were very large (601 to 728 m geometric mean diameter) and fecundity of polyps low, compared with other corals; no reduction in oocyte numbers occurred during oogenesis. Reef-flat species had slightly bigger and fewer eggs than reef-slope species. All species recruited by larvae, but four also multiplied by fragmentation, either year-round or during occasional rough weather. Yearround fragmenters had few larval recruits; non-fragmenters had many, and a rough-weather fragmenter had an intermediate number of larval recruits. It was concluded that larval recruitment largely determined species composition, and that reduced larval recruitment was responsible for sparse distribution of fragmenting species. Subsequent mortality in some species and increase by fragmentation in others probably determined relative abundances. 相似文献
17.
Stefano Goffredo Erik Caroselli Guido Mattioli Francesco Zaccanti 《Marine Biology》2010,157(12):2603-2612
In corals where complex life history processes decoupling age from size (e.g., fragmentation, fusion, partial colony mortality)
are rare or clearly detectable, individual age may be determined from size, and age-based growth and population dynamic models
may be applied. One example is the solitary Mediterranean coral Leptopsammia pruvoti Lacaze-Duthiers 1897, whose population size and structure, and growth rates were determined at Calafuria (43°28′N and 10°20′E),
Ligurian Sea, from December 2007 to June 2009. Growth rate decreased with increasing size. The growth curve derived from field
measurements confirmed the one obtained by growth band analysis. The frequency of individuals decreased exponentially with
age, indicating a steady state population. Turnover time was 2.3 years. Maximum life span was 13 years. Most reproductive
output was from intermediate age classes (6 years), while older individuals (>7 years), although having higher fecundity,
were rare and accounted for a minority of population reproductive output. In comparison with other solitary dendrophylliids,
L. pruvoti life strategy was characterized by a reproduction with r-strategy correlates (high fecundity, short embryo incubation, small planula size, fast achievement of sexual maturity), and
a rate of demographic renewal occurring halfway along the r–K continuum (intermediate turnover time and maximum longevity). 相似文献
18.
B. L. Kojis 《Marine Biology》1986,91(3):291-309
Despite the wide range of morphological diversity among the Acropora (Isopora) colonies on Heron Island (Great Barrier Reef, Australia), only two reproductively isolated species were present from 1977 to 1982: A. cuneata (Dana, 1846) and A. palifera (Lamarck, 1816). Both species released planulae lacking zooxanthellae and were simultaneous hermaphrodites with testes and ovaries occurring on separate mesenteries within the same polyp. Oogenesis preceded spermatogenesis. Seasonal cycles of gametogenesis, embryogenesis and planulation occurred in the two species. Colonies of A. cuneata developed two cycles of gametes. One cycle matured near the first quarter moon in April and the other on the same lunar phase in June. Planulae release occurred from about September to December each year and was not correlated with lunar phase. Gametes of A. palifera ripened only once per annum, a few days after the last quarter moon in November, and planulation occurred from about January to March. Embryos were brooded in the coelenteron of the polyps in both species. Ova were fertilized in the mesenteries and embryos were retained within an envelope of mesoglea and gastrodermis, remaining attached to the mesentery by a stalk until the larvae matured and were released. A. palifera and A. cuneata were abundant in the unpredictable reef flat environment. However, their life-history traits, e.g. seasonal reproduction, delayed sexual maturity, large colony size and fairly long life span, were more specialised than had been predicted for this type of environment. 相似文献
19.
Synchronous spawnings of 105 scleractinian coral species on the Great Barrier Reef 总被引:13,自引:0,他引:13
R. C. Babcock G. D. Bull P. L. Harrison A. J. Heyward J. K. Oliver C. C. Wallace B. L. Willis 《Marine Biology》1986,90(3):379-394
Following observations of mass spawning of hermatypic corals on the Great Barrier Reef in 1981 and 1982, spawning dates were successfully predicted and documented at five reefs on the Central and Northern Great Barrier Reef in 1983. During the predicted times, 105 species from 36 genera and 11 families were observed to spawn. Of these, 15 species were shown to have an annual gametogenic cycle. All but two of the species observed during mass spawnings shed gametes which underwent external fertilization and development. Synchronous spawning was observed both within and between the five reefs studied, which were separated by as much as 5° of latitude (500 km) or almost a quarter of the length of the Great Barrier Reef. The mass spawning of corals took place on only a few nights of the year, between the full and lastquarter moon in late spring. Maturation of gametes coincided with rapidly rising spring sea temperatures. Lunar and diel cycles may provide cues for the synchronization of gamete release in these species. The hour and night on which the greatest number of species and individuals spawned coincided with low-amplitude tides. Multispecific synchronous spawning, or mass spawning, of scleractinian and some alcyonacean corals represents a phenomenon which is, so far, unique in both marine and terrestrial communities. 相似文献
20.
Acroporid corals are the main reef-building corals that provide three-dimensional habitats for other reef organisms, but are
decreasing on many reefs worldwide due to natural and anthropogenic disturbances. In this study, temporal patterns of larval
settlement and survivorship of two broadcast-spawning acroporid coral species, Acropora muricata and A. valida, were examined through laboratory rearing experiments to better understand the potential for larval dispersal of this important
coral group. Many larvae were attached (but not metamorphosed) to settlement tiles on the first examination 3–4 days after
spawning (AS). The first permanent larval settlement (i.e. metamorphosed and permanently settled juvenile polyps) occurred
at 5–6 days AS, and most larval settlement (85–97% of total) occurred within 9–10 days AS. Larval survivorship decreased substantially
to around 50% by the first week of the experiment and to approximately 10% by the second to third week. The rates of larval
attachment, settlement, and the initial drop in survivorship of larvae suggest that effective dispersal of some acroporid
species may largely be completed within the first few weeks AS. 相似文献