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1.
Pikeperch (Sander lucioperca), the studied species, is the most important amongst freshwater fish species, commercially, in the brackish Baltic Sea. We
studied the effects of water temperature on three aspects of pikeperch growth in Haminanlahti bay, Finland. First, annual
length increments were related to age and temperature using a non-linear growth model. Since length increments were based
on back-calculated lengths, i.e. repeated measurements, the first order autoregressive covariance structure was used. The
model showed that when temperature increased annual length increments also increased, whereas increased age reduced annual
length increments. In the modelling, the best fit was found with water degree-days over 10°C. Second, the onset of growth
of pikeperch in spring had a positive relationship with water temperature and a negative one with the length of pikeperch.
The latter finding suggests that smaller, non-mature pikeperch starts to grow earlier than larger, mature pikeperch. Third,
the year-class strength was positively correlated with water degree-days, and the year-class strength negatively affected
annual length increments. This indicates that within a strong year-class subsequent growth is reduced more that within a weak
year-class, suggesting density-dependent growth. 相似文献
2.
3.
Ecological Aspects of the Downstream Migration of Introduced European Eels in the Uono River, Japan 总被引:1,自引:1,他引:0
Takeshi Miyai Jun Aoyama Seji Sasai Jun G. Inoue Michael J. Miller Katsumi Tsukamoto 《Environmental Biology of Fishes》2004,71(1):105-114
We examined the species composition, timing of downstream migration, and biological characteristics of eels using catches at three commercial weirs from 1996 to 1998 in the Uono River, Niigata Prefecture, Japan, which is located farther north in the Japan Sea than where most Japanese eels, Anguilla japonica, recruit. Analyses of a sub-sample of the 292 eels caught in the weirs found that 93.6% were introduced European eels, Anguilla anguilla, that were sexually maturing silver phase eels. Their average age based on otolith annuli was 10.2 years, indicating a relatively high average growth rate of 6.3 cm year–1. Catch records in 1996 and 1997 indicated that downstream migration occurred sporadically from the middle of August to the end of November and that catches generally coincided with abrupt increases in water discharge and drops in water temperature. The highest catches in both years occurred between the last quarter and new moon. These findings were similar to studies on this species in Europe and indicate that A. anguilla can grow rapidly, begin maturation, and start downstream migration far from its native range. This discovery of introduced eels initiating their spawning migration at the same time as A. japonica raises concerns about the potential impact of interbreeding between species and the possible effects on the fishery resources of A. japonica. 相似文献
4.
Gema Hernandez-Milian Sabine Goetz Catuxa Varela-Dopico José Rodriguez-Gutierrez Jorge Romón-Olea José R. Fuertes-Gamundi Edelmiro Ulloa-Alonso Nick J. C. Tregenza Andy Smerdon Monserrat G. Otero Vicente Tato Jianjun Wang M. Begoña Santos Alfredo López Rebeca Lago Julio M. Portela Graham J. Pierce 《Hydrobiologia》2008,612(1):251-268
In the Atlantic, economic losses have been reported from shark, swordfish and tuna longline fisheries due to depredation by
cetaceans. We examined interactions of odontocete cetaceans with commercial longliners operating in waters off Brazil and
the Azores archipelago during 2006–2007, analysing relationships between catches, depredation on hooked fish, cetacean sightings,
acoustic records of cetacean presence and environmental variables. Data were provided by skippers of six vessels and by on-board
observers for two vessels. The percentage of longline sets depredated by cetaceans was low (ranging from 1% to 9% of total
sets per ship) but the proportion of fish damaged was high (up to 100%) when depredation occurred. Catches were related to
the phase of the moon, cloud cover, sea surface temperature and water depth whereas cetacean sightings were primarily related
to catches. In particular there was a positive association between Delphinus delphis sightings and catches of swordfish, and between Stenella frontalis sightings and mako catches. Acoustic detection was low when depredation by false killer whales occurred although high rates
of clicks were detected when delphinids were sighted and false killer whales were by-caught. This may indicate that false
killer whales are not echolocating when feeding on fish hooked on a longline.
Guest editor: V. D. Valavanis
Essential Fish Habitat Mapping in the Mediterranean 相似文献
5.
K. V. Kuzishchin K. Yu. Samoilov M. A. Gruzdeva D. S. Pavlov 《Journal of Ichthyology》2016,56(5):702-714
Biological traits (distribution, reproduction, age composition, body length and weight) of pikeperch Sander lucioperca from channel parts of the Akhtuba River, remote from the Volga Delta, are investigated. In the investigated stretch of the river, movements of most specimens of pikeperch are local and occur in the deep part (4?10 m) of the channel. Aggregations of fish are not confined to any definite points but move along the extensive stretch of broads. Pikeperch prefer near-bottom biotopes confined to the zone of stable hydrodynamic eddies in places of complicated bottom relief—transverse crests and longitudinal channel crests. For the first time, it is found that pikeperch in the under-ice period move to the shallow zone of submersed inshore shrubs. The age structure and body length and weight of pikeperch differ from those in the Volga Delta and correspond more to the populations from northern and northwestern parts of the species area. Pikeperch spawn only in temporary water bodies of the accessory system, within a short period at the temperature 11?17°С. The data on biology of pikeperch from the Akhtuba channel indicate the populational level of differences from the Volga Delta pikeperch. 相似文献
6.
The condition, length and age distribution of pikeperch, Stizostedion lucioperca (L.) in Lake Peipsi
The population of pikeperch in L. Peipsi was studied with respect to average number per haul, length distribution of fishes in experimental catches, condition factor (according to Fulton) and length-weight relationship in autumn 1993–1995.The relatively good growth rate and condition of pikeperch in the lake indicates that the waterbody is suitable for this fish. However, the length and age distribution of pikeperch in different years as well as the decreasing total number of fishes in catches demonstrate that the population of pikeperch is suppressed due to overfishing during the last years. 相似文献
7.
The movements of pikeperch in a shallow reservoir 总被引:5,自引:0,他引:5
The movements of 12 female (62–74 cm) and eight male pikeperch (55–64 cm) radiotagged in early March 1997 in the shallow and turbid Bygholm Reservoir, peaked during the summer, but all fish were also active during the winter. Females moved more than males and their activity was correlated with water temperature. Rate of movement was correlated positively with body size for both male and female pikeperch. During the breeding season (April–May) males became stationary for 14–47 days. Spawning sites, inferred from movements of males, were at depths of 2·0–2·5 m on hard substrata, mainly gravel in areas with many submerged trees and shrubs. Males tended to use the same spawning site the next year. Diel activity pattern varied seasonally but activity was highest from 1800 to 2400 hours. 相似文献
8.
Hans‐Christian John 《Biological Rhythm Research》2013,44(3):169-177
Abstract The mesopelagic fish Astronesthes niger concentrates in the uppermost centimeters of the sea when both sun and moon are below the horizon. Probability of positive catches increases towards the times of lower culmination of sun and moon and perhaps is highest when both culminations are about synchronous. Positive catches were made only when the moon was near its first or third quarter, but this might be somewhat influenced by the material which was not evenly distributed in relation to moonphases. It is assumed that A. niger needs moonlight for vertical migration, but avoids the surface during illumination. 相似文献
9.
The diurnal movements and spatial distribution of adult pikeperch, Sander lucioperca, in the Elbe River, Czech Republic was observed using radio telemetry. The hypothesis that light intensity, within four different
intervals (dawn, day, dusk, night), would determine the spatial distribution of pikeperch in a riverine environment were tested
across a time span of 12 months. During the day, fish were located in deep water of the main channel, moving towards shallower
waters during twilight and residing in the littoral zone, closest to the riverbanks, at night. Movement activity followed
the behavioural pattern in a drainage canal with maximum at twilight and minimum at night. This suggests that nocturnal positions
of adult pikeperch in the shallows were not associated with hunting but more likely with resting.
Handling editor: J. Cambray 相似文献
10.
P. B. Bayley 《Journal of fish biology》1973,5(1):25-40
General studies cover the habitat and life cycle of a migratory population of Prochilodus platensis . Specific studies of this species involved the elucidation and evaluation of abiotic effects on local upstream migrations and preliminary age and growth estimations. Upstream movements appeared to be affected by water temperature and moon phase. Most of the fish moved upstream when the temperature was between about 14 and 18°C at the particular monitoring point. Catches of ascending fish were highest during the full moon quarter, less during the waxing phase and least during the waning and new moon quarters. Length frequency and scale check data allowed approximate, indirect estimations to be made of the modal lengths attained in each of the first five age-groups. 相似文献
11.
H. Lehtonen J. Lappalainen J. Kervinen E. Fontell 《Zeitschrift fur angewandte Ichthyologie》2006,22(6):540-542
The spawning sites of pikeperch were mapped using artificial spawning nests in the clay‐turbid Lake Tuusulanjärvi in southern Finland to protect the most important spawning areas. Altogether 272 artificial spawning nests were set before actual spawning on potential spawning grounds. The first observations of eggs were made on 26 May at a surface water temperature of 12°C. No new eggs were found after 10 June at water temperature of 16°C. The nests were removed on 18 June when the larvae had already hatched. The study demonstrated that artificial spawning nests could be used to evaluate both duration and spatial dimensions of spawning of pikeperch. 相似文献
12.
The fish community in Tjeukemeer was monitored from 1971 to 1988 by trawling, and during the summer of 1988 the distribution of the more abundant species was determined in relation to size and location. Bream, pikeperch and smelt were the most dominant fishes, whereas roach, white bream, perch and ruffe comprised <10% of the total catches. After the termination in 1977 of the intensive gillnet fishery both pikeperch >50 cm and bream >30 cm increased in biomass, but roach >15 cm and perch >15 cm virtually disappeared and pikeperch <50 cm substantially decreased. Only smelt, ruffe, white bream and bream <30 cm hardly changed in biomass. Bream, pikeperch, perch and smelt were restricted to the open water zone, but roach <15 cm and 0 + bream were confined to the littoral zone. White bream and ruffe did not show a distinct habitat preference. Because the recruitment of smelt is largely dependent on immigration from the IJsselmeer, a feed-back between the smelt and pikeperch population is lacking. Because the carrying capacity of the pikeperch population is mainly determined by smelt, the other fish <15 cm are very vulnerable to predation when the smelt population is consumed, before a new year-class of smelt is recruited, or when the smelt fails to recruit. The vulnerability to predation of the different species and their feeding habits are discussed in relation to their distribution. 相似文献
13.
The growth rates of pikeperch (Lucioperca lucioperca L.) originating from two lowlands ponds in the north of Belgium, one of which is heated by the effluents of power plants, were compared by means of scalimetry and operculometry. The overall condition of the fish in both ponds was also investigated. The pikeperch grew significantly faster in heated water, although overall condition was comparable. Seasonal variations resulted in the heated pond arriving at a temperature higher than the optimum. 相似文献
14.
The relation of biotic and abiotic interactions to eutrophication in Tjeukemeer,The Netherlands 总被引:2,自引:2,他引:0
Eddy H. R. R. Lammens 《Hydrobiologia》1990,191(1):29-37
During the summer months of 1974–1985 chlorophyll-a and total P concentration, biomass of Daphnia hyalina, smelt Osmerus eperlanus, bream Abramis brema and pikeperch Stizostedion lucioperca, water temperature and water intake from lake IJsselmeer were monitored in Tjeukemeer. During this period there were manipulations with the bream and pikeperch stocks as a consequence of the termination of a gill-net fishery in 1977, and larval smelt immigrated each year from the large lake IJsselmeer and contributed largely to the yearly smelt recruitment.The correlation matrix of the nine variables mentioned above showed a positive correlation between bream and chlorophyll-a, but surprisingly a negative one between smelt and chlorophyll-a. The latter can only be explained when smelt is the dependent variable. In a multi-linear regression there was a negative effect of temperature, chlorophyll a and pikeperch on smelt and a positive effect of water intake. Daphnia hyalina was negatively influenced by the biomass of smelt and the water intake of lake IJsselmeer. The positive relation of Daphnia hyalina and chlorophyll-a was probably related to better survival chances of D. hyalina in an Oscillatoria-rich environment when smelt is the most important predator. An increasing biomass of bream coincided with higher total-P levels and probably contributed to higher chlorophyll-a levels. 相似文献
15.
We analysed lake smelt (Osmerus eperlanus eperlanus m. spirinchus Pallas.) population dynamics in relation to water level and temperature in Lake Peipsi, Estonia/Russia, using commercial
fishery statistics from 1931 to 2004 (excluding 1940–1945). Over this period, smelt provided the greatest catch of commercial
fish although its stock and catches have gradually decreased. At times, catches of smelt were quite variable with a cyclic
character. Disappearance of smelt from catches in years 1973–1975 was the result of summer fish kill. Regression analysis
revealed a significant negative effect of high temperature on the abundance of smelt stock, while the effect of water level
was not significant. Our results suggest that critical factors for the smelt population are the absolute value of water temperature
in the hottest period (≥20°C) of summer and the duration of this period. These weather parameters have increased in synchrony
with smelt decline during the last 7 decades. There appeared to be a significant negative effect of hot summers on the abundance
of smelt operating with a lag of one and 2 years, which can be explained by the short life cycle (mainly 1–2 years) of this
species. 相似文献
16.
In this study, the relative role of spatio‐temporal factors and associated environmental variables (water transparency and temperature) were quantified in relation to gillnet samples of fishes in a large and shallow lake (Lake Balaton, Hungary). Most of the variance (56·1%) in the relative abundance data (%) was related to the vertical segregation of fishes. This gradient substantially affected the catch per unit effort (CPUE) by number of the dominant species, the surface‐oriented bleak Alburnus alburnus and the benthic common bream Abramis brama. It also influenced total CPUE, mean fish mass and species richness and diversity. At the lake level, horizontal habitat heterogeneity (i.e. littoral v. offshore) accounted for only 8·3% of the total variance in relative abundance data, but was important in structuring the CPUE of the ruffe Gymnocephalus cernua and the pikeperch Sander lucioperca. The longitudinal environmental gradient (i.e. lake basin), year and season of sampling, water transparency and temperature had significant effects on relative abundance only at the habitat level, but were also important components of variability of CPUE in some species at the lake level. As sampling schemes need to consider the main gradients in fish assemblage distributions, the use of surface and pelagic gillnets should be more intensively incorporated in the study and monitoring of fish assemblages in shallow lakes and lake habitats. 相似文献
17.
Experiments were carried out between 1999 and 2001 on pikeperch fingerlings using two feeds at four stocking densities to evaluate the success of training 35‐day‐old pond‐reared pikeperch, Stizostedion lucioperca L., to lifeless feed in intensive culture. Training periods of 28 days for each of three cohorts (1999–2001) were applied to introduce pikeperch from zooplankton to minced feed. In a preliminary study (1999), two feeds (live prey and minced fish meat) were compared at two stocking densities. Two higher densities were investigated in 2000 and 2001 and matched with the minced fish diet. Different feeds had significant effects on feed consumption and, as a consequence, on body weight gain; fish fed live prey showed highest growth rates. Unexpectedly, the stocking density had no significant effect on growth, and at the highest density there was a significantly betterfeed conversion rate. Stocking density and feed type significantly influenced the feeding behaviour. Three characteristic foraging techniques are described. 相似文献
18.
The behaviour of radio-tagged adult pikeperch (Stizostedion lucioperca (L.)) from two areas in the Danish River Gudenaa were recorded prior to, and during the spawning period. Eight of 13 tagged fish in the lower reaches of the river were located throughout the whole study. Five of these fish moved upstream to various sites in the river prior to spawning, which occurred from late April to June. The three remaining fish moved to the fjord. These movements were interpreted as a spawning migration, and it is suggested that the lower reaches of the River Gudenaa constitute an over-wintering area for pikeperch, which use different spawning areas. Ten pikeperch caught just downstream of an impassable hydropower plant were radio-tagged and translocated upstream of the dam to a reservoir. Within a week, half of the fish moved to a lake situated more than 30 km upstream the reservoir. This behaviour is hypothesised to be a homing response. The study reveals that the pikeperch is a highly mobile species with a complicated migration pattern, even in relatively small river systems. 相似文献
19.
Fish impingement at power stations situated along the rivers Rhine and Meuse in The Netherlands 总被引:2,自引:0,他引:2
R. H. Hadderingh G. H. F. M. van Aerssen L. Groeneveld H. A. Jenner J. W. Van Der Stoep 《Aquatic Ecology》1983,17(2):129-141
Summary Substantial numbers of predominantly O+ fish were impinged on the cooling water screens of Harculo, Gelderland, Merwedehaven and Amer power stations. Low numbers were impinged at the two stations located on the river Meuse (Maas and Claus). Two possible reasons for this difference are suggested,viz. a low fish density in the river Meuse and the deep position of the cooling water intakes. In comparison with Bergum power station situated on a lake the impingement rate at the river stations was more than ten times as low.Most fish were impinged during the summer months when large numbers of juvenile fish are present in the rivers. Dominating species impinged were roach, pikeperch, bream and perch. The abundance of pikeperch in the screensamples, points to a recent increase in the population of pikeperch in the rivers. The growth pattern of O+ pikeperch and O+ roach during summer seemed very similar for power stations located at different rivers. Thirty fish species and four crustacean species were collected, among whichOrconectus limosus was quite abundant at Maas and Claus power stations. 相似文献
20.
Juanita De Los Ríos-Méndez Gabriela A. Kanamori Mauricio F. Landaeta 《Journal of fish biology》2019,95(3):833-846
The influence of the lunar cycle on the feeding habits, feeding success and selectivity was tested in situ on larval stages of the clingfish Gobiesox marmoratus (Gobiesocidae). Gobiesox marmoratus larvae and their prey were collected in the water column during the lunar cycle in austral spring 2015 and 2016, in shallow waters (<30 m depth) of El Quisco, central Chile. Feeding incidence was high (80–100%) throughout the moon cycle. The diet was composed of 32 prey items, being gastropod larvae and invertebrate eggs the most important. Prey composition varied among lunar phases with the lowest prey richness during new moon. During 2016, G. marmoratus larvae ingested the lowest number, but the largest prey during new moon. In spring 2015, there were no significant changes in the abundance of each prey taxon in the water column among moon phases, but in spring 2016 there were significant differences in the abundance of cypris and copepod nauplii, particularly between full and new moon. Feeding selectivity index showed that gastropod larvae were positively selected throughout the lunar cycle during spring 2015. In spring 2016, invertebrate eggs were selectively ingested in full moon and third quarter, but at a new moon G. marmoratus larvae selected gastropod larvae. Mean temperature of the water column and its vertical gradient and nocturnal cloud cover influences the feeding success of larval G. marmoratus. Lunar illumination favoured only an increase of richness of prey items. Therefore, nocturnal cloud cover precludes a greater influence of lunar illumination in the larval trophic ecology of this crypto-benthic fish. 相似文献