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1.
Despite an Indo-Pacific wide distribution, the movement patterns of grey reef sharks (Carcharhinus amblyrhynchos) and fidelity to individual reef platforms has gone largely unstudied. Their wide distribution implies that some individuals have dispersed throughout tropical waters of the Indo-Pacific, but data on large-scale movements do not exist. We present data from nine C. amblyrhynchos monitored within the Great Barrier Reef and Coral Sea off the coast of Australia. Shark presence and movements were monitored via an array of acoustic receivers for a period of six months in 2008. During the course of this monitoring few individuals showed fidelity to an individual reef suggesting that current protective areas have limited utility for this species. One individual undertook a large-scale movement (134 km) between the Coral Sea and Great Barrier Reef, providing the first evidence of direct linkage of C. amblyrhynchos populations between these two regions. Results indicate limited reef fidelity and evidence of large-scale movements within northern Australian waters.  相似文献   

2.
Welsh JQ  Bellwood DR 《PloS one》2012,7(3):e33187
Although a few pelagic species exhibit regional endothermy, most fish are regarded as ectotherms. However, we document significant regional endothermy in a benthic reef fish. Individual steephead parrotfish, Chlorurus microrhinos (Labridae, formerly Scaridae) were tagged and their internal temperatures were monitored for a 24 h period using active acoustic telemetry. At night, on the reef, C. microrhinos were found to maintain a consistent average peritoneal cavity temperature 0.16 ± 0.005 °C (SE) warmer than ambient. Diurnal internal temperatures were highly variable for individuals monitored on the reef, while in tank-based trials, peritoneal cavity temperatures tracked environmental temperatures. The mechanisms responsible for a departure of the peritoneal cavity temperature from environmental temperature occurred in C. microrhinos are not yet understood. However, the diet and behavior of the species suggests that heat in the peritoneal cavity may result primarily from endogenous thermogenesis coupled with physiological heat retention mechanisms. The presence of limited endothermy in C. microrhinos indicates that a degree of uncertainty may exist in the manner that reef fish respond to their thermal environment. At the very least, they do not always appear to respond to environmental temperatures as neutral thermal vessels and do display limited, but significant, visceral warming.  相似文献   

3.
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5.
Ceratomyxa spp. from the gall-bladder of five members of the family Serranidae were examined for their taxonomic identity. This paper describes seven new ceratomyxid species, i.e. C. brayi n. sp. and C. whippsi n. sp from Cephalopholis boenak (Bloch); C. cutmorei n. sp. from Epinephelus fasciatus (Forsskål); C. gleesoni n. sp. from Plectropomus leopardus (Lacépède); C. hooperi n. sp. and C. nolani n. sp. from E. quoyanus (Valenciennes); and C. yokoyamai n. sp. from E. maculatus (Bloch). Each species is characterised morphologically and small subunit (SSU) rDNA sequences. All seven new species have so far been found in only a single host species.  相似文献   

6.
>Two hiatuses in coral skeleton growth, associated tissue death and subsequent regrowth, were discovered while dating eight multi-century Porites coral cores collected from the central Great Barrier Reef (GBR), Australia. Cross-dating of characteristic annual luminescent lines visible in the coral core slices under UV-light (Hendy et al. 2003) accurately dated the two events to 1782–85 and 1817 a.d.. Die-off scars were observed in only one core for each event. X-radiographs and photographs taken under UV-light show the pattern of regrowth and the period taken by the coral to recover. Bioerosion, predominately by boring sponges ( Cliona spp.), of the exposed coral surface following the 1782–85 event caused a hiatus of up to 14 years' growth, with the coral taking 7–8 years to reclaim the whole surface contained within the 9-cm-diameter core. Contemporary historical and proxy-climate records indicate that El Niño climatic conditions occurred at the time of both growth discontinuities. Intense luminescence observed in corals growing continuously during the 1817 event suggests that low salinity from river runoff was a contributing factor, analogous environmental conditions to those that were associated with the 1998 bleaching event in the GBR.  相似文献   

7.
Gynichthys diakidnus n. g., n. sp. (Digenea: Cryptogonimidae) is described from the fish Plectorhinchus gibbosus (Lacépède) (Perciformes: Haemulidae) off Heron and Lizard Islands on the Great Barrier Reef, Australia. The monotypic Gynichthys n. g. is distinguished from all other cryptogonimid genera by the combination of a fusiform body, the lack of oral spines, a forebody that occupies approximately half or more of the body length, a deeply lobed ovary, opposite to slightly oblique testes, a seminal vesicle that is confined mainly in the forebody and the presence of multiple gonotyls in the form of two small slightly muscular pores or pseudosucker-like structures in the mid-line well anterior to the ventral sucker. Bayesian inference analysis of LSU rDNA data revealed that G. diakidnus n. sp. grouped relatively distant to species of the cryptogonimid genus Oligogonotylus Watson, 1976, which also have multiple gonotyls, suggesting that the presence of multiple gonotyls is homoplasious and has thus at least evolved twice in the family. The secondary structure of the internal transcribed spacer 2 (ITS2) rDNA region was inferred for G. diakidnus using minimum free energy and homology modelling algorithms. A four helix model was inferred with helices I and IV being relatively short (<30 nucleotides) and helix three being the longest; this structure is homologous with that observed for other digeneans and eukaryotes in general.  相似文献   

8.
Reproduction and recruitment are key processes that replenish marine populations. Here we use the Palau archipelago, in the western Pacific Ocean, as a case study to examine scales of connectivity and to determine whether an oceanographic model, incorporating the complex reef architecture, is a useful predictor of coral recruitment. We tested the hypothesis that the reefs with the highest retention also had the highest densities of juvenile coral density from 80 field sites. Field comparisons showed a significant correlation between the densities of juvenile Acropora colonies and total larval recruitment derived from the model (i.e., calculated as the sum of the densities of larvae that self-seeded and recruited from the other reefs in the archipelago). Long-distance larval imports may be too infrequent to sustain coral populations, but are critical for recovery in times of extreme local stress.  相似文献   

9.
The bird remains from Valbro belong only to three taxa, Paraortyx lorteti, Archaeotrogon venustus, and A. zitteli. This association makes it possible to ascribe to this locality an early Oligocene age, reference-levels MP 22 or MP 23, which is in agreement with the age given by the mammals.  相似文献   

10.
A new species of digenean, Pseudobacciger cheneyae n. sp., is described from the intestines of Weber’s chromis (Chromis weberi Fowler & Bean) from off Lizard Island, Great Barrier Reef, Australia. This species differs from the three described species of Pseudobacciger Nahhas & Cable, 1964 [P. cablei Madhavi, 1975, P. harengulae Yamaguti, 1938 and P. manteri Nahhas & Cable, 1964] in combinations of the size of the suckers and the length of the caeca. The host of the present species is a perciform (Family Pomacentridae) which contrasts with previous records of the genus which are almost exclusively from clupeiform fishes. The genus Pseudobacciger is presently recognised within the family Faustulidae (Poche, 1926) but phylogenetic analyses of 28S and ITS2 rDNA show that the new species bears no relationship to species of four other faustulid genera (Antorchis Linton, 1911, Bacciger Nicoll, 1924, Paradiscogaster Yamaguti, 1934 and Trigonocryptus Martin, 1958) but that instead it is nested within the Gymnophalloidea (Odhner, 1905) as sister to the Tandanicolidae (Johnston, 1927). This result suggests that the Faustulidae is polyphyletic.  相似文献   

11.
Icthyological results of four rapid assessment surveys are presented. The surveys were completed between 1997–1999 and were conducted at the following localities: Milne Bay (Papua New Guinea), Calamianes Islands (Palawan, Philippines), Togean–Banggai Islands (Sulawesi, Indonesia), and Weh Island (Sumatra, Indonesia). Surveys were conducted over periods ranging from 9 to 22 days and consisted mainly of underwater observations while scuba diving, supplemented with small rotenone and spear gun collections. Milne Bay was characterized by a high percentage of pristine reef environments and supported the largest number of species (1040). Diversity was generally lower at the Philippine and Indonesian sites due to more habitat homogeneity and higher fishing pressure, including the widespread use of illegal fishing methods, including cyanide and explosives.  相似文献   

12.
Anna St?pień 《ZooKeys》2013,(337):35-47
A new species of Numbakulla Guţu & Heard, 2002 (Tanaidacea) is described from Heron Island (southern Great Barrier Reef, Queensland) collected during the Census of Coral Reefs Ecosystem (CReefs) program. The new species is the third member of the family and can be recognized by the combination of characters as: length/width ratio of the body, which is 6:7, pereonite 4 longer than the rest, the presence of eyes, a blunt rostrum, antenna article 2 elongated, cheliped carpus with row of inner setae, pereopod 6 carpus with spines, pleopod endopod with denticles.  相似文献   

13.
Community-wide feeding interrelationships in a low-diversity coral reef off the Pacific coast of Panamá (Uva Island reef) demonstrate complex pathways involving herbivore, strong corallivore, and carnivore interactions. Four trophic levels with 31 interguild links are identified in a generalized food web, and documented feeding interrelationships with 287+ species links are portrayed in a coral–corallivore subweb. The importance of trophic groups changes greatly with time, from unknown causes over annual to decadal-scale periods, and during very strong El Niño–Southern Oscillation events such that intermittent intense herbivory by echinoids (Diadema) and corallivory by gastropod mollusks, the crown-of-thorns sea star Acanthaster, hermit crabs, and fishes result in high levels of coral mortality and bioerosion of reef substratum. Intraregional differences in species composition and abundances affecting food-web interactions are briefly described for nonupwelling (Uva Island) and upwelling areas (Pearl Islands) in Panamá. Seasonal upwelling in the Pearl Islands results in high plankton productivity, which likely augments production in invertebrates, fishes, marine mammals, and seabirds, but these pathways still remain largely unquantified. The corallivore Acanthaster is absent from upwelling centers in Panamá and from upwelling and nonupwelling areas in the southern and central Galápagos Islands, and the highly destructive, facultative corallivore Eucidaris galapagensis occurs only in the latter offshore islands and at Cocos Island. Relatively recent declines in the abundances of manta rays, sharks, and spiny lobsters are correlated with, but not necessarily causally linked to, increasing fishing activities in the late 1970s to early 1980s. The extent to which the complex yet highly unstable Uva Island food web is representative of other eastern Pacific coral reef ecosystems remains to be investigated.  相似文献   

14.
Small‐scale population differentiation among coral reef fishes may be more common than previously thought. New molecular technologies have informed patterns of differentiation, while experimental approaches focusing on larval abilities to limit distribution have explored processes leading to diversification. Building upon a recently published paper by Wismer et al. that examined population level differences in learning and cooperative behaviors in cleaner wrasse (Labroides dimidiatus), we use a phylogenetic framework to explore how social behaviors are distributed among wrasses in the Labrichthyines clade. Establishing links between social behavior and speciation across the phylogeny allows us explore how social behaviors such as learning and cooperation may also act as possible mechanisms driving diversification at the microevolutionary scale.  相似文献   

15.
In 1994 and 1995, 131 visual censuses of reef fishes were made using the stationary sampling method in Courtown, Albuquerque, Serrana and Roncador, four atolls of the Archipelago of San Andrés and Old Providence in the Southwestern Caribbean. Fish species and their abundances were recorded in four geomorphologic zones: lagoon, windward barrier reef, windward terrace and forereef terrace. A total of 98 species were censused; the most abundant were Chromis cyanea (14%), Clepticus parra (14%) and Stegastes partitus (10%). The most abundant families were Pomacentridae (37%), Labridae (28%) and Scaridae (10%). Analysis of similarities showed that differences between zones were greater than differences between atolls, but lagoon and forereef terrace were not significantly different. Cluster and ordination analysis confirmed these results; in addition, the ordination analysis placed the groups according to depth and wave-exposure gradients, suggesting that these two physical variables were responsibles for the clustering. Differences in equitability and species richness appear also due to these variables. Inverse analysis showed in each group few characteristic species, then the differences between zones were due specially to dominance of some species. The dominant trophic categories were planktivorous and herbivorous that were significantly different between zones. In shallow zones (shallow lagoonal patch reefs) and high wave-exposed zones (winward barrier reef) dominated herbivorous fishes, while in deeper zones (terraces and deep lagoonal patch reefs) planktivorous were more abundant.  相似文献   

16.
Parts of coral reefs from New Caledonia (South Pacific) were registered at the UNESCO World Heritage list in 2008. Management strategies aiming at preserving the exceptional ecological value of these reefs in the context of climate change are currently being considered. This study evaluates the appropriateness of an exclusive fishing ban of herbivorous fish as a strategy to enhance coral reef resilience to hurricanes and bleaching in the UNESCO-registered areas of New Caledonia. A two-phase approach was developed: 1) coral, macroalgal, and herbivorous fish communities were examined in four biotopes from 14 reefs submitted to different fishing pressures in New Caledonia, and 2) results from these analyses were challenged in the context of a global synthesis of the relationship between herbivorous fish protection, coral recovery and relative macroalgal development after hurricanes and bleaching. Analyses of New Caledonia data indicated that 1) current fishing pressure only slightly affected herbivorous fish communities in the country, and 2) coral and macroalgal covers remained unrelated, and macroalgal cover was not related to the biomass, density or diversity of macroalgae feeders, whatever the biotope or level of fishing pressure considered. At a global scale, we found no relationship between reef protection status, coral recovery and relative macroalgal development after major climatic events. These results suggest that an exclusive protection of herbivorous fish in New Caledonia is unlikely to improve coral reef resilience to large-scale climatic disturbances, especially in the lightly fished UNESCO-registered areas. More efforts towards the survey and regulation of major chronic stress factors such as mining are rather recommended. In the most heavily fished areas of the country, carnivorous fish and large targeted herbivores may however be monitored as part of a precautionary approach.  相似文献   

17.
The locality Valbro (Quercy, France) has yielded a rich fossil vertebrate fauna. Here are presented the geological context, a preliminary faunal list and the systematics of the Rodentia and carnivores, the most abundant taxa of the fauna. The Rodentia are known from 11 taxa: the Theridomyidae Blainvillimys gregarius Schlosser, 1884, Blainvillimys ?gemellus Vianey-Liaud, 1989, Issiodoromys medius (Vianey-Liaud, 1976) and S. cayluxi Schlosser, 1884, the Aplodontidae Plesispermophilus angustidens Filhol, 1882, the Gliridae Butseloglis tenuis (Bahlo, 1975), Butseloglis micio (Misonne, 1957) and Bransatoglis planus (Bahlo, 1975), the Sciuridae Palaeosciurus goti Vianey-Liaud, 1974 and cf. Oligopetes sp., and the Cricetidae Atavocricetodon sp. aff. A. nanus (Pelaez-Campomanes, 1995). Thirteen taxa of carnivores are present at Valbro; among the Hyaenodontida: Hyaenodon leptorhynchus Laizer et Parieu, 1838 and cf. Apterodon sp.; among the Carnivora: a Feliformia gen. et sp. indet., the Nimravidae Nimravus intermedius (Filhol, 1872), Dinailurictis bonali Helbing, 1922 and Nimravidae gen. et sp. indet. (Certainly belonging to one the two already identified species), the Ursida Pachycynodon crassirostris Schlosser, 1888, Pachycynodon sp., Amphicynodon sp. 1 cf. A. typicus (Schlosser, 1888), Amphicynodon ? sp. 2 and Ursida gen. et sp. indet. cf. Pachycynodon boriei (Filhol, 1876), the Mustelida M. olivieri Bonis, 1997, the Carnivora incertae sedis Palaeogale sectoria (Gervais, 1848–1852), the Arctoidea gen. et sp. indet. and Carnivora gen. et sp. indet. (probably representing taxa already identified at lower taxonomic levels). The evolutionary grade of B. gregarius of Valbro compares to that of the species from Mas de Got, La Plante 2 and Cavalé, which supports an MP22 age for Valbro. This datation is further supported by the association of Theridomyinae yielded by the locality (B. gregarius, B. gemellus, I. medius and S. cayluxi), and by the presence of a N. intermedius that well compares the material of the species from Villebramar, La Plante et Mas de Got, of D. bonali, P. sectoria, M. olivieri (species known only from Mas de Got), and by additional evidence from the remaining vertebrates from Valbro, especially the squamates. Despite a limited amount of specimens (341 specimens have been studied), the faunas of rodents and carnivores from Valbro are the most speciose and diverse known for the MP22 level and, for the Carnivora fauna in particular, for the Oligocene of the Old World.  相似文献   

18.
Negative hands, occasionally with incomplete fingers, are often found in Paleolithic caves but so far have received no definitive explanation. Nowadays they are more commonly seen as the expression of a gestural language. In this paper, we suggest that the negative hands visible in the Cosquer cave and dating from around 27?000 BP could represent counting on fingers. Several arguments are developed to support this hypothesis. Furthermore we also suggest that the dots and dashes often associated with negative hands in numerous caves, might be another, more advanced way of representing numbers.  相似文献   

19.
极罕见的复杂易位t(2;18;21;9;19;13)核型一例   总被引:3,自引:1,他引:2  
张廉生  徐先早 《遗传》1991,13(3):29-30
我室于1988年检出一例涉及2、18、21、9、19、13号共6条染色体复杂易位的患者。本核型极为罕见,在国内外文献中尚无报道,现报告如下: 一、病例报告 患儿梅××,女,生于1976年12月,死于1989年1年,存活12年。患儿系第一胎,足月  相似文献   

20.
A large survey program was conducted during 1985/1986 to determine the extent of activity of the crown-of-thorns starfish, Acanthaster planci, and its broad effects on the coral communities of the Great Barrier Reef (GBR). The perimeters of 228 reefs (about 9% of reefs in the GBR system) were surveyed within 1 year using rapid survey, manta tow techniques. These reefs encompassed the broad latitudinal and longitudinal gradients within the GBR. Approximately 27% (62 reefs) of the reefs surveyed had recently experienced (18%), or were experiencing (9%), an outbreak of the crown-of-thorns starfish. These outbreaks were mainly confined to reefs in the central third of the GBR (between Lizard Island and Townsville) and had affected, to varying degrees, approximately 65% of the reefs surveyed within this region. A greater proportion of mid-shelf reefs had experienced outbreaks than outer-shelf reefs, although this difference was not statistically significant. Of the small number of inner-shelf reefs surveyed, none had been recently affected by an outbreak. Large active outbreaks of starfish were reported on many of the reefs located off Townsville while much smaller outbreaks were found on several reefs at the southern end of the GBR, in the Swain Reef complex. Almost 86% of reefs currently experiencing an outbreak had moderate to high coral mortality over at least a third of their perimeters. Only 10% of reefs with active outbreaks had high coral mortality over most of their windward and leeward margins. A similar proportion of reefs had low to moderate coral mortality over less than a third of their perimeters.  相似文献   

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