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1.
Spatial, temporal and habitat-related variation in the abundance of large predatory fish at One Tree Reef, Australia 总被引:1,自引:1,他引:0
Patterns of abundance of large piscivorous fish (>200 mm TL) were documented at two spatial and four temporal scales within
the main lagoon of One Tree Reef on Australia’s Great Barrier Reef. Grouper (Serranidae), snapper (Lutjanidae) and wrasses
(Labridae) were the most abundant large piscivores. On a large scale (hundreds of metres), patterns of predator abundance
were consistently greater on the inner edge than centre of the lagoon over a range of temporal scales: days, weeks, months
and years. On a small spatial scale (tens of metres), the abundance of large predatory fish was patchy. At both spatial scales,
fish were consistently aggregated in particular areas and associated with specific structural features of the reef habitat.
Predator abundance was high where live corals were predominant and the topography was more complex. Hence, predation pressure
and its potential effects on the distribution and abundance of prey populations, both in time and space, may vary greatly
within lagoonal environments.
Accepted: 25 May 1997 相似文献
2.
Phillip S. Lobel 《Environmental Biology of Fishes》1992,33(4):351-358
Synopsis Low frequency sounds are shown to be associated with the spawning of two Caribbean coral reef fishes: the hamlet, Hypoplectrus unicolor (Serranidae) and the striped parrotfish, Scarus iserti (Scaridae). Both fishes produce distinctive sounds while broadcasting gametes in midwater. H. unicolor produces sounds via muscle stimulation of the swimbladder. Fin movements among group spawning S. iserti produce hydrodynamic noise. Although reproductive behaviors of these two species have been previously studied in detail,
the association of sounds with mating is new. The mating sounds cannot be easily detected by human hearing underwater but
are recordable using a hydrophone. The sounds are distinct and recognizable enough to allow counting and acoustic mapping
of mating events in these species. 相似文献
3.
Marcus P. Lincoln Smith 《Environmental Biology of Fishes》1989,26(1):29-37
Synopsis A number of factors can influence the accuracy and precision of underwater visual transect techniques. Among these are observer swimming speed and, during multispecies surveys, the effect of counting all fishes on estimates of particular species. This paper examines the effect of these factors on population estimates of inconspicuous fishes (defined as Type 1) in a temperate reef fish assemblage near Sydney, Australia. Counting Type 1 fishes with all others yielded significantly lower estimates of species richness and abundance than when counted alone. This suggests that multispecies surveys should be split into 2 or more counts, using a census procedure that is appropriate to the group of species cencused. Further, the effect of counting all other fishes on estimates of Type 1 fishes varied according to the relative abundance of the former: their effect was lowest when abundance of other fishes was lowest. There was a negative relationship between observer speed and estimated abundance for Type 1 fishes. Survey precision of Type 1 fishes was generally improved by surveying at slower observer speeds. 相似文献
4.
The availability of variable genetic markers for groupers (Serranidae) has generally been limited to mitochondrial DNA. For studies of population genetic structure, more loci are usually required; particularly useful are those that are nuclear in origin such as microsatellites. Here, we isolated and characterized 9 microsatellite loci from the endemic Hawaiian grouper Epinephelus quernus using a biotin-labeled oligonucleotide-streptavidin–coated magnetic bead approach. Of the 20 repeat-containing fragments isolated, 15 had sufficient flanking region in which to design primers. Among these, 9 produced consistent polymerase chain reaction product, and 6 were highly variable. These 6 loci were all composed of dinucleotide repeats, with the number of alleles ranging from 6 to 18, and heterozygosities from 33.3% to 91.7%. The high levels of variability observed should make these markers useful for population genetic studies of E. quernus, and potentially other epinephelines. 相似文献
5.
Matthew T. Craig 《Ichthyological Research》2007,54(1):81-84
A preliminary analysis of 175 specimens of the white-streaked grouper, Epinephelus ongus (Serranidae), was undertaken to determine life history characteristics of the species. Sagittal otoliths, stomachs, and a
subsample of gonads were removed to determine age at length, diet, and reproductive strategy. The von Bertalanffy growth equation
was used to describe growth in this species and yielded the growth parameters L∞ = 438.3, K = 0.04334, and t0 = −8.752. Fish ranged in age from 1 to 20 years. Diet was consistent with other serranid species and included crabs, shrimps,
octopi, and fishes. Based on a very limited number of specimens (n = 12), the larger size and older age of males compared to females suggests that E. ongus may be a protogynous hermaphrodite. 相似文献
6.
Richard S. Nemeth Jeremiah Blondeau Steve Herzlieb Elizabeth Kadison 《Environmental Biology of Fishes》2007,78(4):365-381
This study compared the spatial and temporal patterns of red hind, Epinephelus guttatus, movement and migration from annual spawning aggregations on St Thomas (STT) and St Croix (STX), United States Virgin Islands.
Around STT E. guttatus migrated 6–33 km from a functional spawning migration area of 500 km2 and around STX E. guttatus migrated 5–18 km from an area of 90 km2. Similarities between sites were found in regards to timing of movement, temporal and spatial changes in sex ratios, annual
and lunar predictability and were synchronized with environmental cues. E. guttatus spawning aggregations in the Virgin Islands occur between the winter solstice (i.e., after December 20) and about February
20 of any year and show a distinctive peak 20–40 days after the winter solstice. Spawning typically occurred during periods
of declining seawater temperature and slacking currents within a temperature range of 26–27.5°C and current speed of 2.5–3.5 cm s−1. Males arrived early to spawning sites and stayed longer than females. These gender-based behavioral patterns are important
to E. guttatus reproductive dynamics and must be factored into future studies and the design of fisheries regulations to ensure sustainability
of spawning aggregation sites. The predictability of E. guttatus spawning aggregations relative to the winter solstice will be extremely beneficial for defining the temporal and spatial
aspects of area closures. The consistency and synchrony of movement and migration will improve both the efficiency of planning
research and monitoring programs and directing enforcement activities during critical time periods. Applying this knowledge
strategically will maximize the limited resources available for research and enforcement and lead to greater protection of
spawning aggregations. 相似文献
7.
MANUEL ALEJANDRO RAMÍREZ JENNY PATRICIA‐ACEVEDO SILVIA PLANAS JOEL L. CARLIN STEPHAN M. FUNK W. OWEN MCMILLAN 《Molecular ecology resources》2006,6(3):813-817
We characterized nine microsatellite loci and identified an additional 60 genomic regions containing microsatellites in the red hind grouper, Epinephelus guttatus. The nine loci were highly polymorphic, and primers designed from red hind genomic DNA produced a strong amplification product in a test panel of 16 other groupers in the genera Epinephelus and Mycteroperca collected from across the world. Most of the amplified regions were homologous to the red hind locus and a well‐defined microsatellite repeat was generally evident. The nine loci, together with the 60 uncharacterized microsatellite‐containing regions, provide a powerful tool for ecological and evolutionary studies in groupers. 相似文献
8.
A new anthine fish, Pseudanthias calloura, is described on the basis of three specimens from Palau. The new species differs from other congeners in having a complicated
color pattern of the caudal fin and the following characters: moderately forked caudal fin; dorsal fin with 10 spines, the
anterior ones being shorter than the rest, and with 16 soft rays; second anal spine shorter than the third; 19 pectoral rays;
scales on lateral line 51 (holotype) to 53 (paratypes) in number; tongue without teeth; circumorbital rim with several fleshy
projection on posterior part; a row of fine scales occurring asymmetrically behind alternate dorsal spines on both left and
right sides; preopercle margin finely serrated; interopercle and subopercle margins smooth.
Received: June 9, 1999 / Revised: September 23, 2000 / Accepted: February 23, 2001 相似文献
9.
George R. Forster 《Environmental Biology of Fishes》1984,10(3):129-136
Synopsis Ninety six fish belonging to 19 species were taken by deep water line fishing off Aldabra. Analysis of the results shows how various factors such as hooking time changed with depth. The change of bottom temperature with depth was examined. The zone between 100 m and 150 m was found to have considerable temperature variations. The distribution of some serranids and lutjanids appeared to be stratified though there was usually overlap in the range of adjacent species. The results are compared with previous line-fishing off the South coast of Aldabra from deeper water and other areas of the western Indian Ocean. 相似文献
10.
The Noronha wrasse Thalassoma noronhanum was recorded cleaning 19 client fish species at Fernando de Noronha Archipelago, o. north–eastern Brazil. The preferred clients were non–dangerous, mostly planktivorous species, whereas the potentially dangerous, predatory species were rarely cleaned. T. noronhanum acts as a cleaner in two distinct ecological situations, at and outside the cleaning stations, and attends different client species in each of them. Potentially dangerous clients were mostly attended outside the cleaning stations. Many attacks and two instances of predation on the cleaner wrasse by the grouper client Cephalopholis fulva were recorded. The attacks occurred on individual wrasses foraging near the bottom outside the cleaning stations. 相似文献