scholarly journals Diel variation in the ascent of fishes up an experimental fish ladder at Itaipu Reservoir: fish size, reproductive stage and taxonomic group influences

2007 ◽  
Vol 5 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Domingo Rodriguez Fernandez ◽  
Angelo Antonio Agostinho ◽  
Luis Mauricio Bini ◽  
Fernando Mayer Pelicice
Keyword(s):  
Reproductive Stage ◽  
Fish Length ◽  
Diel Variation ◽  
Management Tools ◽  
Prochilodus Lineatus ◽  
Fish Size ◽  
Fish Ladder ◽  
Taxonomic Groups ◽  
Pimelodus Maculatus ◽  
Diel Period

In this study, we evaluated the fish ascent in the experimental ladder at Itaipu Reservoir (Paraná State, Brazil), in relation to diel variation, fish size, reproductive stages and species composition. The study was carried out from October, 1995 to February, 1996 and from November, 1996 to January, 1997 at two points on the ladder (boxes at heights of 10 and 27 m). Twenty-two species were recorded, and Prochilodus lineatus, Pimelodus maculatus, Leporinus obtusidens, Schizodon borellii and Leporinus friderici accounted for 86.6 % of the total catch. Fish length did not differ between diel periods and boxes. On the other hand, fish abundance of the main species was significantly influenced by box position, reproductive stage and diel period. The higher box showed lower abundance, suggesting some selectivity in ascension. The ability to ascend the ladder did not show any relationship with reproductive migration, since non-reproductive adults comprised most of the catch. An interesting finding is that the major taxonomic groups showed specific diel preferences in ascending the ladder: Characiformes ascended the ladder predominantly during daylight, whereas Siluriformes migrated at night. These results emphasize how complex ladders are as management tools, and stress the need to acquire information on several aspects as a condition to achieve conservation goals.

scholarly journals Evaluation of fish passage through the Igarapé Dam fish ladder (rio Paraopeba, Brazil), using marking and recapture

2007 ◽  
Vol 5 (2) ◽  
pp. 233-236 ◽  
Author(s):  
Carlos Bernardo Mascarenhas Alves
Keyword(s):  
Power Plant ◽  
Retention Time ◽  
Fish Community ◽  
Thermal Power ◽  
Fish Passage ◽  
Home Ranges ◽  
Community Studies ◽  
Tag Retention ◽  
Fish Ladder ◽  
Pimelodus Maculatus

Rio Paraopeba, a tributary of rio São Francisco, has a six-meter high dam, built in 1978 to divert water to the Igarapé Thermal Power Plant. In 1994, a fish ladder was built at this dam. The results of a marking and recapture program carried out along rio Paraopeba between 1997 and 2001 are described, using information from fish community studies conducted at ten sampling stations between 1994 and 1997. These investigations showed the presence of at least 91 species in the river. During four rainy seasons between 1997 and 2000, fish were caught downstream of the dam, marked with external plastic tags, and immediately released at the same site. The objective was to evaluate fish passage through the ladder, based on recapture information from artisanal and sport fishermen. A total of 3,642 specimens were marked, adding up to a biomass of approximately 1.33 tons. Twenty-six species were used, representing 28.5% of the total recorded richness (91 species). Maximum recorded tag retention time was 10 months. Total recapture rate was 4.37% in four years, reaching 5.75% in the last period (2000-2001). Of all recaptured specimens, 14.0% were caught upstream of the dam, evidencing passage through the ladder. The specimens recaptured upstream of the dam belonged to three species: piau-verdadeiro (Leporinus obtusidens), mandi-amarelo (Pimelodus maculatus) and curimatá-pioa (Prochilodus costatus). These species showed linear home ranges of 15.4, 81.5 and 232.0 km, respectively. Most recaptures occurred immediately downstream of the dam, one of the most intensely fished stretches of rio Paraopeba.

scholarly journals Comparing on site human and video counts at Igarapava fish ladder, south eastern Brazil

2006 ◽  
Vol 4 (2) ◽  
pp. 291-294 ◽  
Author(s):  
Mark D. Bowen ◽  
Simone Marques ◽  
Luiz G. M. Silva ◽  
Volney Vono ◽  
Hugo P. Godinho
Keyword(s):  
Fish Species ◽  
Accurate Method ◽  
Fish Passage ◽  
Southeastern Brazil ◽  
Human Observer ◽  
Full Spectrum ◽  
Prochilodus Lineatus ◽  
Number Of Species ◽  
Fish Ladder ◽  
Number Of Individuals

On site human observations and video images were collected and compared at the window of the Igarapava Dam fish ladder (IDFL), rio Grande , Southeastern Brazil, between March 1st and June 30th, 2004. We conducted four experiments with two humans (Observer 1 and Observer 2) observing fish passage in the IDFL window while a Sony 3CCD video camera (Observer 3) recorded fish passage at the same time. Experiments, each one hour in length, were distributed throughout the diel cycle using full spectrum lights. We identified fish species, the number of individuals for each species, and the real time that they passed. Counts from each human observer were compared to the video counts. The fish species most commonly observed in the window were - curimba (Prochilodus lineatus), mandi-amarelo (Pimelodus maculatus), piau-três-pintas (Leporinus friderici) and ferreirinha (Leporinus octofasciatus). The number of species and individuals were indistinguishable for the three observers. But, the number of species and individuals were significantly different among experiments. Thus, the three observers register the same number of species and count the same number of individuals even when these two response variables differ significantly among experiments. Based on these results, we concluded that the video count was an accurate method to assess fish passage at the IDFL.

scholarly journals Reynolds shear-stress and velocity: positive biological response of neotropical fishes to hydraulic parameters in a vertical slot fishway

2012 ◽  
Vol 10 (4) ◽  
pp. 813-819 ◽  
Author(s):  
Bernardo Alan de Freitas Duarte ◽  
Isabella Cristina Resende Ramos ◽  
Hersília de Andrade e Santos
Keyword(s):  
Shear Stress ◽  
Fish Species ◽  
Velocity Fluctuation ◽  
Reynolds Shear Stress ◽  
Neotropical Fishes ◽  
Fish Ladder ◽  
Vertical Slot ◽  
Structure Of Flow ◽  
Vertical Slot Fishway ◽  
Pimelodus Maculatus

The barriers created by dams can cause negative impacts to aquatic communities, and migratory fish species are directly affected. Fishways have been developed to allow the upstream passage of fishes through dams. In Brazil, after the implementation of environmental laws, these structures have been built based on European and American fishway designs. Studies have shown selectivity for different neotropical fishes in some Brazilian fishways, and the main challenge has been to promote upstream passage of a large number of diverse fish species. The patterns of flow circulation within the fish ladder may explain fish selectivity although few studies detail the fish response to hydraulic characteristics of fish ladder flow. This paper presents a laboratory study, where a vertical slot fishway was built in a hydraulic flume and the behavior of two neotropical fish species (Leporinus reinhardti and Pimelodus maculatus) were analyzed. The structure of flow was expressed in terms of mean velocity, Reynolds shear-stress and velocity fluctuation fields. The individuals of Leporinus reinhardti had higher passage success than Pimelodus maculatus in the laboratory flume. Both species preferred areas of low to zero Reynolds shear-stress values. In addition, different preferences were observed for these species concerning the horizontal components of velocity fluctuation.

16.P9. Fish ladder selects biological traits in upstream migrating curimbata, Prochilodus lineatus

2007 ◽  
Vol 148 ◽  
pp. S71-S72
Author(s):  
G.L. Volpato ◽  
R.E. Barreto ◽  
A.L. Marcondes ◽  
P.S.A. Moreira ◽  
M.F.B. Ferreira
Keyword(s):  
Biological Traits ◽  
Prochilodus Lineatus ◽  
Fish Ladder

scholarly journals Associations among Fish Length, Dam Passage History, and Survival to Adulthood in Two At-Risk Species of Pacific Salmon

2019 ◽  
Author(s):  
James R. Faulkner ◽  
Blane L. Bellerud ◽  
Daniel L. Widener ◽  
Richard W. Zabel
Keyword(s):  
At Risk ◽  
River Basin ◽  
Pacific Salmon ◽  
Juvenile Fish ◽  
Fish Length ◽  
Hydroelectric Dams ◽  
Successful Management ◽  
Fish Size ◽  
Seaward Migration ◽  
Pass Through

AbstractThreatened or endangered salmon and steelhead originating in the Snake River basin must pass through a series of eight major hydroelectric dams during their seaward migration. Understanding the effects of specific dam passage routes on lifetime survival for these stocks is essential for successful management. Juvenile fish may pass these dams via three primary routes: 1) spillways; 2) turbines; or 3) juvenile bypass systems, which divert fish away from turbines and route them downstream. Bypass systems may expose fish to trauma, increased stress, or disease. However, numerous studies have indicated that direct survival through bypass systems is comparable to and often higher than that through spillways. Some researchers have suggested that route of dam passage affects mortality in the estuary or ocean, but this is complicated by studies finding fish size affects route of passage. We tested whether passage through bypass systems was associated with probability of adult return after accounting for fish length and other covariates for two species of concern. We also investigated the association between fish length and probability of bypass at dams, and how this relationship could lead to spurious conclusions regarding effects of bypass systems on survival if length was ignored. We found that: 1) larger fish had lower bypass probabilities at 6 of 7 dams; 2) larger fish had higher probability of surviving to adulthood; 3) bypass history had little association with adult return after accounting for length; and 4) simulations indicated spurious effects of bypass on survival may arise when no true bypass effect exists, especially in models without length. Our results suggest that after fish leave the hydropower system, bypass passage history has little effect on mortality. Our findings underscore the importance of accounting for fish size in studies of dam passage or survival.

scholarly journals Assessing fish assemblages similarity above and below a dam in a Neotropical reservoir with partial blockage

2013 ◽  
Vol 73 (4) ◽  
pp. 727-736 ◽  
Author(s):  
FG. Araújo ◽  
ABI. Santos ◽  
RJ. Albieri
Keyword(s):  
Fish Assemblage ◽  
Fish Assemblages ◽  
Fish Passage ◽  
Migratory Species ◽  
Wet Season ◽  
Prochilodus Lineatus ◽  
Oxygen Conductivity ◽  
Composition And Structure ◽  
Pimelodus Maculatus ◽  
Hoplosternum Littorale

Damming rivers disrupts the water flow and changes the ichthyofauna organisation. We investigated an impoundment with permanent connection and homogeneous environmental conditions between the zones above and below the dam. Temperature was comparatively higher during wet season irrespective of zone, and both zones had higher dissolved oxygen, conductivity and transparency in the dry season. A total of 1687 individuals comprising 27 species were collected in the downriver zone, while the reservoir had 879 individuals and 23 species. Each zone had different fish assemblage composition and structure, but assemblages were not explained by the examined environmental variables (r2 = 0.08; p = 0.307). Migratory species such as Pimelodus maculatus, Pimelodus fur, Leporinus copelandii and Prochilodus lineatus were the most affected, and probably are prevented to perform upriver migrations. On the other hand, lentic adapted species such as G. brasiliensis, Hoplias malabaricus and Hoplosternum littorale successfully colonised the reservoir. Therefore we conclude that the presence of the lateral hydrological connectivity alone does not guarantee the ecological connectivity since fish assemblage similarity differed between the two zones. Fish passage facilities should be monitored and managed to evaluate and improve their functionality.

Methylmercury in fish from the southern Baltic Sea and coastal lagoons as a function of species, size, and region

2017 ◽  
Vol 33 (6) ◽  
pp. 503-511 ◽  
Author(s):  
Lucyna Polak-Juszczak
Keyword(s):  
Fish Species ◽  
Total Mercury ◽  
Coastal Lagoons ◽  
Length Distribution ◽  
Fish Length ◽  
Consumer Health ◽  
Fish Size ◽  
Toxic Compound ◽  
Muscle Tissues ◽  
The Central Nervous System

Background: Methylmercury (MeHg) is a highly toxic compound that traverses the blood–brain barrier with deleterious effects to the central nervous system. Exposure is generally through the ingestion of contaminated fish. Fish are a main source of MeHg. Goals and methods: The aim of this study was to determine the dependence of MeHg concentrations on fish species and age, the percentage of MeHg in total mercury (THg) and risk assessment depending on the size of fish. Assays of THg and MeHg were performed on the muscle tissues of 18 species of fish. Results: The investigations indicated there were differences in the mercury concentrations depending on fish size. THg and MeHg concentrations in the muscles of fish species that have a wide length distribution were strongly, positively correlated with fish length. However, concentrations of MeHg were strongly, positively correlated with those of THg in all the fish species investigated. Variation in the percentage share of MeHg in THg in the muscles of fish of large sizes was also noted within species, but this correlation was not noted in small-sized fish. The dose of MeHg in small-sized fish species was estimated and the risk posed to consumer health was assessed using mean MeHg concentrations determined for different fish species. Conclusions: For species of fish that occur within a wide length distribution, the dose of MeHg should be assessed separately in different length classes. Fish consumption of small-sized species poses no health risk.

Somatic Growth Effects on the Otolith–Fish Size Relationship in Young Pond-reared Striped Bass, Morone saxatilis

1989 ◽  
Vol 46 (1) ◽  
pp. 113-121 ◽  
Author(s):  
David H. Secor ◽  
John Mark Dean
Keyword(s):  
Growth Rate ◽  
Striped Bass ◽  
Somatic Growth ◽  
Morone Saxatilis ◽  
Fish Length ◽  
Fish Size ◽  
Somatic Growth Rate ◽  
Size Relationship ◽  
Highly Correlated ◽  
Otolith Size

Somatic growth rate of pond-reared larval and juvenile striped bass, Morone saxatilis, influenced the relationship between otolith size and fish size. Slower growing groups of individuals had larger and heavier otoliths, relative to fish length, than did faster growing groups. Within each growth group, otolith and fish size were highly correlated. Daily increment formation was validated from 10 to 51 d after hatch. Significant interaction occurred between age and fish size effects on otolith size. We propose that otolith growth occurs by two interacting processes. Otoliths grow daily in an incremental manner which is independent of somatic growth. Growth also proceeds continuously within each daily cycle of increment deposition, probably in some proportion to daily somatic growth. Corollaries to the hypotheses are (1) somatic growth rate can influence the otolith–fish size relationship, (2) intraspecific variation in otolith scaling might be used to predict past differences in somatic growth rate, and (3) there is a biological rationale for the use of otolith size and fish size as predictors in age estimation.

Reproductive dynamics of broadbill swordfish, Xiphias gladius, in the domestic longline fishery off eastern Australia

2003 ◽  
Vol 54 (4) ◽  
pp. 315 ◽  
Author(s):  
Jock Young ◽  
Anita Drake ◽  
Michael Brickhill ◽  
Jessica Farley ◽  
Thor Carter
Keyword(s):  
New Zealand ◽  
Gonadosomatic Index ◽  
Fork Length ◽  
Reproductive Period ◽  
Fish Length ◽  
Batch Fecundity ◽  
Spawning Period ◽  
Fish Size ◽  
Eastern Australia ◽  
Xiphias Gladius

The reproductive ecology of broadbill swordfish, Xiphias gladius, was evaluated based on 1437 fish (size range 50–300 cm orbital fork length [OFL]) caught in the domestic longline fisheries off eastern Australia and New Zealand between May 1999 and March 2001. Reproductive activity was assessed using histology, a gonadosomatic index, and maximum oocyte size. Males were significantly smaller than females and represented less than one third of the sampled fish. Sex ratio differed significantly with respect to fish size and time of year. Females began maturing at 150-cm OFL and spawned from September to March, with the greatest activity from December to February. Males matured at 90-cm OFL; ripe males were found from January to March, but also in May and October, suggesting an extended reproductive period. During the spawning period the proportion of spawning to inactive mature sized females was significantly higher in waters west of longitude 158°E than in waters to the east. Further to the east, samples taken from the New Zealand fishery showed no actively spawning fish during the main spawning period. Females were increasingly reproductively active as water temperature increased beyond 24°C and sea surface chlorophyll a decreased below 0.2 μg L–1. Batch fecundity was linearly related to fish length with a mean batch fecundity of 1.66 million oocytes for females ranging in size from 173- to 232-cm OFL. The presence of hydrated oocytes and post-ovulatory follicles (POFs) in the same ovaries indicated multiple spawnings. Depending on the time taken for POFs to degrade, these may have been daily at the height of the spawning season.

scholarly journals The relationship between fish length and otolith size and weight of Acanthopagrus arabicus Iwatsuki, 2013 (Sparidae) collected from the Iraqi marine waters

2021 ◽  
Vol 20 (1) ◽  
pp. 27-34
Author(s):  
Laith Jawad ◽  
◽  
Audai Qasim ◽  
Faleh Musa Al-Zaidy ◽  
Baradi Waryani ◽  
...  
Keyword(s):  
Linear Models ◽  
Arabian Gulf ◽  
Fish Length ◽  
Marine Waters ◽  
Fish Size ◽  
Length Width ◽  
Relationship Of ◽  
The Relationship ◽  
Otolith Size

Fish specimens (n=75) of A. arabicus were collected from the marine waters of Iraq at Khor al-Zubair. Collection was conducted in the period February–September 2019 at depth of 10–25 m. Relationships between fish length and otolith length, width and weight were calculated for the Arabian yellowfin seabream, Acanthopagrus arabicus using linear models. This study represents the first data available on the relationship of fish size and otolith size and weight for A. arabicus in the Arabian Gulf area. The various relationships between fish length otolith length, width and weight were calculated: Y = -1E – 0.06X2 + 0.0106X + 5.2628, Y = 4E – 06X2 + 0.0077X + 2.1834, and Y = 9E – 07X2 + 0.0013X – 0.191 respectively.

Sign in / Sign up

Export Citation Format

Share Document