Fish Community Biomass Research Articles

Modification of feeding strategies of grey herons (Ardea cinerea L.) in response to a major decline in the preyed fish community's biomass

(2000). Modification of feeding strategies of grey herons (Ardea cinerea L.) in response to a major decline in the preyed fish community's biomass. SIL Proceedings, 1922-2010: Vol. 27, No. 5, pp. 3192-3194.

Natural fishing experiments in marine reserves 1983-1993: community and trophic responses

This study examined the effect of fishing on the density, biomass, species richness and overall structure of the reef fish community at two islands (Sumilon and Apo) in the Philippines from 1983 to 1993. A series of natural fishing experiments over this period involving marine reserves were monitored at each island, where estimates of fishing intensity and selectivity were available. Fishing intensity (15% and 25% of biomass removed per year at Sumilon and Apo, respectively) was high enough to affect total community biomass, but not density, significantly. Species richness was not affected significantly by fishing, except at Sumilon reserve. The fishery was relatively non-selective with most families/trophic groups caught roughly in proportion to their contribution to community biomass. Thus fishing did not alter the relative abundance of the major families/trophic groups significantly, except during a period of use of explosives and drive nets in the Sumilon reserve. At the level of family/trophic group the community displayed strong resilience of structure. There was little evidence of secondary effects e.g. declines in abundance of large predators resulting in measurable increases in abundance of their prey. This resilience of the community to the effects of fishing most likely results from three important community attributes (open nature of the component populations, likely maintenance of upstream recruitment supply and apparent lack of any obvious “keystone” species or families) and one important characteristic of the fishery (relatively non-selective with respect to the components of the community).

Impacts of predator depletion by fishing on the biomass and diversity of non-target reef fish communities

An understanding of the indirect effects of fishing on predator-prey relationships is required for the development of valid multispecies yield models for reef fisheries and for determining the factors governing fish community structure at larger scales. We used an underwater visual census technique to examine the indirect effects of fishing on the biomass and diversity (species richness) of reef fishes in a series of ten traditional Fijian fishing grounds (qoliqoli) subject to a range of fishing intensities. All members of the families Chaetodontidae (butterflyfishes), Labridae (wrasses), Lutjanidae (snappers), Mullidae (goatfishes), Scaridae (parrotfishes) and the sub-family Epinephelinae (groupers and coral trout) which could be reliably identified were censused. Each species censused was assigned to one of three trophic groups: herbivore, invertebrate feeder or piscivore. The biomass of all piscivorous fishes and of large (>30 cm) piscivorous fishes differed significantly between qoliqoli and was significantly correlated with fishing intensity. However, the biomass of piscivorous fishes was not correlated with the biomass or diversity of their potential prey (which were not targeted by the fishery). This suggested that the indirect effects of fishing did not have an important bearing on fish diversity or biomass and that predation by the target species did not play an important role in structuring these Fijian reef fish communities. The results contrast with those from a number of studies at smaller scales and provided further indications that the structure of reef fish communities is not governed by a single dominant process, but by a range of processes which operate on different scales in different circumstances.

Species diversity, vertical distribution and biomass of reef fish communities with reference to spatial structures of reefs in Onagawa Bay and Sendai Bay, Japan.

Species diversity, vertical distribution and biomass of reef fish communities with reference to spatial structures of reefs in Onagawa Bay and Sendai Bay, Japan.

Abundance, Biomass, and Species Richness of Fish Communities in Relation to Nitrogen-Loading Rates of Waquoit Bay Estuaries.

Previous articleNext article No AccessECOLOGYAbundance, Biomass, and Species Richness of Fish Communities in Relation to Nitrogen-Loading Rates of Waquoit Bay EstuariesJ. Tober, C. Fritz, E. LaBrecque, P. J. Behr, and I. ValielaJ. Tober Search for more articles by this author , C. Fritz Search for more articles by this author , E. LaBrecque Search for more articles by this author , P. J. Behr Search for more articles by this author , and I. Valiela Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Biological Bulletin Volume 191, Number 2October 1996 Published in association with the Marine Biological Laboratory Article DOIhttps://doi.org/10.1086/BBLv191n2p321 Views: 24Total views on this site Copyright © 1996 by Marine Biological LaboratoryPDF download Crossref reports no articles citing this article.

Comparison of Fish Assemblages Sampled by a Shrimp Trawl and a Fish Trawl in St Vincent Bay, New Caledonia

The spatial and temporal patterns of variation of a tropical soft-bottom fish community sampled by a shrimp trawl and a fish trawl were compared at two sites, North and South Bay, of St Vincent Bay, New Caledonia. Results indicated that the species richness and particularly the species composition were related to the type of trawl. However, the overall density and biomass, species diversity, and evenness did not vary significantly as a function of gear type. The same species dominated the catches of the two trawl types, but differences appeared between density, biomass and mean weight of particular species, calculated from the shrimp and the fish trawl catches. The spatial variations of the community structure were comparable between the two gear types, though the composition of the species assemblages were not the same. Differences appeared for the temporal structures. These differences were insignificant in one of the sampled sites (North Bay), but more important in the other site (South Bay), where species diversity, size range of the individuals, and shape diversity of fishes were more important. However, the major differences between the community structures remained the same, independent of sampling gear type. These results validate studies comparing spatial and temporal patterns of variations in general characteristics (i.e. number of species per haul, density, biomass, species diversity and evenness) of tropical soft-bottom fish communities determined by shrimp and fish demersal otter trawls. This also validates the determination of species assemblages especially spatial assemblages. However, important problems may arise when more particular points are studied, such as species composition of the communities, determination of the characteristic species of the assemblages, or study of a particular species.

Effects of Fishing Effort and Catch Rate Upon the Structure and Biomass of Fijian Reef Fish Communities

An improved understanding of fishing effects is required to assess the sustainability of existing fishing practices and to determine the ecological implications of offering fishing concessions in marine reserves. The effects of fishing were investigated in six Fijian fishing grounds (qoliqoli) subject to different fishing intensities. A visual census technique was used to determine the structure and biomass of the shallow-water reef fish communities targeted by the fishers. A supervised voluntary logbook scheme was used to assess the size and composition of yield from the qoliqoli. The fish communities in the least intensively fished qoliqoli were significantly different from fish communities elsewhere. The significance of these differences was attributable to the greater biomass of invertebrate feeding and piscivorous fishes in the least intensively fished qoliqoli. Annual yields of herbivorous fishes ranged from 0.3 to 5.2% of the biomass estimated by visual census. There were no significant differences in herbivore biomass among qoliqoli subject to different fishing intensities. The biomass of invertebrate feeding fishes was significantly higher in the least intensively fished qoliqoli. The biomass of invertebrate feeding/piscivorous fishes was significantly higher in the two least intensively fished qoliqoli. In the two least intensively fished qoliqoli the estimated annual yields of invertebrate feeding and invertebrate feeding/piscivorous fishes did not exceed 4% of the biomass estimated by visual census. However, yields of these trophic groups approached 20% of biomass in the intensively fished qoliqoli where biomass was significantly lower. The fishing effects observed were primarily attributed to significant differences between the fish communities in the least intensively fished qoliqoli and all others. Thus, at higher fishing intensities, the biomass of target species provided a poor index of relative fishing pressure. The results suggest that the annual removal of 5% of fish biomass may cause significant structural changes in reef fish communities. Thus, it is important to ensure that fishing concessions and poaching activities are carefully regulated in marine reserves.

Density, biomass and community structure of demersal fishes off the Pacific coast of northeastern Japan

Demersal fish communities were studied on the lower continental shelf and the upper continental slope along the Pacific coast of northeastern Japan. Species composition, number and weight of each species were examined based on otter trawl samples at 45 stations. Mean density and biomass of demersal fishes were 131 ha ‐1 and 21 kg ha ‐1 , respectively. The ten most abundant species comprised of about 95% of total number and weight of overall catch indicating simple species composition. Gadiform fishes Theragra chalcogramma, Gadus macrocephalus and Physiculus maximowiczi were the most important species by number, weight and frequency of occurrences, and three main community types represented by the three key species were recognized. Theragra-dominant community showed higher density and biomass, and lower diversity than Physiculus-dominant community did. Species diversity of demersal fish community was negatively correlated to density and biomass. Density and biomass of demersal fish community were high on the uppermost slope, and the high abundance resulted from low-diversity communities dominated by T. chalcogramma and G. macrocephalus.

Factors Related to the Biomass and Production of Fish Communities in Small, Oligotrophic Lakes Vulnerable to Acidification

We estimated biomass and production of the fish community in 19 small (<50 ha) lakes from four watersheds in central Ontario. Lake pH ranged from 4.8 to 7.1. We found 19 fish species in these lakes; yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), white sucker (Catostomus commersoni), and largemouth bass (Micropterus salmoides) were the most common. On average, there were 4.5 species per lake. Neither fish community biomass nor production was significantly different among the communities identified by cluster analysis, and the number offish species was not lower at lower pH. More than 75% of each lake's total biomass was confined to less than three fish species. Whole-lake fish biomass was related to the total number of species in the lakes and their average age. Fish community production was related to fish biomass, averge fish size, and acid neutralizing capacity (ANC) with an almost equal influence provided by each factor. At lower ANC and pH, fish were usually smaller in weight and often had lower population growth rates. In these lakes where the influence of lake size and trophic status was minimized, fish community biomass and production were only secondarily related to lake pH or ANC.

Yield of Yellow Perch in Lakes Erie and St. Clair: Community Associations

Abstract Commercial catches of yellow perch Perca flavescens in the Canadian gill-net fishery of Lake Erie declined in the 1970s, even though fishing effort increased and mesh size decreased between 1970 and 1975. Multiple stepwise regression of annual catch (kg) on effort (km gill net), recruitment by year-class, total fish community biomass, and weight at age 3 showed that only recruitment explained a significant portion of the variations in catches in the eastern basin, and only weight was important in the western basin. Year-class strength declined in the late 1960s and 1970s; catches from both experimental and commercial gear provided some indication of improvement by the 1980s. Although recruitment was associated with variations in the abundance of some species in four fish communities (Lake St. Clair and the three basins of Lake Erie), there was no evidence that any common groups of species were regulating recruitment. Fish community structures were similar (discriminant function analysis) in the e...

Fish Community Structure, Biomass, and Production in the Turkey Lakes Watershed, Ontario

The Turkey Lakes Watershed contains four lakes, and the headwater lake (Batchawana Lake) consists of two distinct basins, neither of which supports a native, reproducing fish stock. Fish biomass varied by a factor of 3.3 among the other three lakes in the watershed. Fish flesh production varied by a factor of only 1.5 in the system. Salmonid and small cyprinid contribution to biomass and production increased with progression downstream. Both fish biomass and production per unit surface area decreased with increasing lake depth. The fish biomass and production in the watershed was strongly influenced by depth, but alkalinity and phytoplankton carbon assimilation also were related to stock and production. Wishart Lake, immediately below Batchawana Lake, has a fish stock with restricted recruitment, and cyprinids make only a limited contribution to the observed production. Although both these conditions may be symptomatic of lake acidification, it is unclear whether the situation in this watershed results from lake acidification or biogeographic factors.

The Effect of Competition with Yellow Perch on the Survival and Growth of Planted Brook Trout, Splake, and Rainbow Trout in a Small Ontario Lake

Abstract Matched plantings of hatchery-reared yearling brook trout (Salvelinus fontinalis) and splake (Salvelinus namaycush × S. fontinalis) or brook trout and rainbow trout (Salmo gairdneri) were made in Little Minnow Lake for 6 yr prior to and 6 yr following the introduction of yellow perch (Perca flavescens). The mean return for each kilogram of fish planted was 3.3, 6.8, and 6.1 kg, respectively, for brook trout, splake, and rainbow trout in pre-perch years but after yellow perch became established the mean returns were 0.4, 0.9, and 0.8 kg, respectively, all less than the weight planted. The 1967, 1969, and 1972 year classes of yellow perch successively dominated the fish community and yellow perch biomass fluctuated between 20 and 30 kg/hectare. The establishment of yellow perch resulted in a drastic change in the food habits of the planted salmonids and a reduction in their growth rates in excess of 50%. The evidence strongly indicates that planted salmonids could not compete successfully with yell...