Preliminary observations of migrating adult freshwater eels (Anguilla australis australis Richardson) in Tasmania

The downstream migration of maturing adult short-finned eels, A. a. australis, was recorded at an eel trap on the Clyde River during the 1981-1982 season. 5.2 t of eels entered the trap from November to April with 53% of the catch taken during January. Of the 190 eels examined, only a single male specimen was found. Female A. a. australis migrated downstream at a mean length of 94.5 cm, a mean weight of 1700 g and a mean age of 22.1 years (range 18-30 years). There was a significant positive correlation between catch and water temperature, temperatures above 12�C being associated with eel migration. The peak catch occurred during January and coincided with the highest record of mean daily water temperature (20.5�C). The migration did not appear to be influenced by moon phase, and river flow was controlled.

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Upstream migration by young pigmented freshwater eels (Anguilla australis australis Richardson) in Tasmania

Marine and Freshwater Research ◽

10.1071/mf9840061 ◽

1984 ◽

Vol 35 (1) ◽

pp. 61 ◽

Cited By ~ 25

Author(s):

RD Sloane

Keyword(s):

Water Temperature ◽

Fresh Water ◽

River Flow ◽

Late Spring ◽

Day Length ◽

Upstream Migration ◽

Single Specimen ◽

Anguilla Australis ◽

And Control ◽

Freshwater Eels

During late spring and summer, upstream migrations by young pigmented freshwater eels (elvers) can be seen at stream barriers in Tasmania. The elver runs at two major hydro-electric dams, Trevallyn and Meadowbank, were sampled regularly during the period 1977-1981 and migrations at a number of smaller stream barriers throughout Tasmania were also investigated. Migrating elvers were found to be short-finned eels, A. a. australis; only a single specimen of the long-finned eel, A. reinhardii Steindachner, was recorded. Elvers sampled at inland stream barriers were both larger and older than those found nearer the sea, indicating that eels migrate farther upstream for several years in succession. Eels involved in upstream migration were found to be shorter than 25 cm, having spent up to 10 years in fresh water. Day length, water temperature and river flow may all contribute to the initiation and control of elver migrations. The numbers of elvers involved in annual migrations at major hydro- electric dams in Tasmania are substantial: the largest migration occurs at Trevallyn, where between 3 × 106 and 5 × 106 elvers take part each year. These elvers represent a considerable stocking poterltial and could be used to expand the local wild-eel fishery.

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Experimental Studies on the Thermal Performance of the Balcony-Type Flat-Plate Solar Water Heater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.953-954.111 ◽

2014 ◽

Vol 953-954 ◽

pp. 111-114

Author(s):

Sheng Xian Wei ◽

Fen E Hu ◽

Dong Yu Li ◽

Hui Li

Keyword(s):

Water Temperature ◽

Flat Plate ◽

Temperature Rise ◽

Thermal Efficiency ◽

Solar Collector ◽

Water Heating ◽

Solar Water Heating ◽

Solar Water ◽

Daily Water Temperature ◽

Daily Water

Based on the test methods for solar water heating systems, the unsteady thermal efficiency, the daily thermal efficiency and the daily water temperature rise of the balcony-type solar water heating system with a flat-plate solar collector fixed at a large tilt angle (≥60o) have been discussed by the experimental test in Kunming. The results indicate that the average daily thermal efficiencies of the solar collector installed at 60o, 70o, 80o and 90o are around 0.35, 0.39, 0.34 and 0.40. The intercept and the slope of the unsteady thermal efficiency equations are about 0.36~0.44 and 1.62~4.01W·°C-1·m-2. The average daily water temperature rise is 25.2°C, 20.1°C, 18.2°C and 17.4°C for the solar collector fixed at 60o, 70o, 80o and 90o.

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Growth modelling in accordance with daily water temperature in European grayling (Thymallus thymallusL.)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-031 ◽

1999 ◽

Vol 56 (6) ◽

pp. 994-1000 ◽

Cited By ~ 24

Author(s):

J P Mallet ◽

S Charles ◽

H Persat ◽

P Auger

Keyword(s):

Growth Rate ◽

Water Temperature ◽

Good Description ◽

Biological Significance ◽

Temperature Fluctuations ◽

Fish Growth ◽

Von Bertalanffy ◽

European Grayling ◽

Daily Water Temperature ◽

Daily Water

The model of von Bertalanffy has been and is still widely used to model fish growth, mainly because of its good description of annual growth over the whole life span. However, it does not take into account a seasonal variability in growth rate, an important phenomenon that appears quite well correlated with water temperature fluctuations in temperate climates. In the present study, we demonstrated that it was possible to model such variations by including daily water temperature in the von Bertalanffy growth formula owing to the correlation between the growth coefficient k and water temperature. The model we chose to describe such a correlation includes parameters with obvious biological significance and is mathematically well structured, which allowed an extensive use of our growth model. Hence, we use our new model to describe annual variability in the growth of European grayling (Thymallus thymallus L.) in a river section where water temperature could rise up to the thermal tolerance limit for this species, inducing reduced growth rates and severe mortality events. Finally, we were able to explain the growth rate variability from one year to the next by interannual water temperature fluctuations.

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Peer Review #2 of "Modelling daily water temperature from air temperature for the Missouri River (v0.1)"

10.7287/peerj.4894v0.1/reviews/2 ◽

2018 ◽

Keyword(s):

Water Temperature ◽

Peer Review ◽

Air Temperature ◽

Missouri River ◽

Daily Water Temperature ◽

Daily Water

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Performance Analysis of Integrated Collector System with Immersed Coil Heat Exchanger

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.660.740 ◽

2014 ◽

Vol 660 ◽

pp. 740-744 ◽

Cited By ~ 4

Author(s):

Lukmon Owolabi Afolabi ◽

Hussain Hamoud Al-Kayiem ◽

Tesfamichael Baheta Aklilu

Keyword(s):

Heat Exchanger ◽

Water Temperature ◽

System Efficiency ◽

Daily Water Temperature ◽

Solar Intensity ◽

Collector Efficiency ◽

Daily Water ◽

The Mean ◽

Coil Heat Exchanger ◽

Coil Heat

The performance of integrated solar collector / thermal energy storage with immersed heat exchanger was investigated experimentally at the Solar Research Site, University Technology PETRONAS, (4.4224oN, 100.9904oE), Malaysia. The experimental set up consisted of 150 liters storage tank capacity with immersed coil heat exchanger, single glazing 1.5m2 flat plate collector with 15o tilt to the horizontal. The circulation of the working fluid was by forced in closed loop with a mini solar pump. Aluminum cell foam was attached to the absorber as extended surface. The surface of the collector was coated with black ornament to improve its absorption. The system was tested under clear skys, for two cases; with and without water drawn-off for seven days per case studied. The performance evaluation data obtained for case1 at the mean maximum solar intensity was 503.98 W/m2 were: maximum daily water temperature 63°C, average daily water temperature 46°C, collector efficiency 63% and system efficiency 43%. Whilst for case 2, the mean maximum solar intensity was 473.11 W/m2, the maximum daily water temperature 54°C, average daily water temperature 39.36°C, collector efficiency 54% and system efficiency 39%. The system efficiency for case 2 showed that the heat exchanger performed slighlty better and the water drawn-off effect is minimal.

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Comparison of Historical Water Temperature Measurements with Landsat Analysis Ready Data Provisional Surface Temperature Estimates for the Yukon River in Alaska

Remote Sensing ◽

10.3390/rs13122394 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2394

Author(s):

Carson Baughman ◽

Jeffrey Conaway

Keyword(s):

Standard Deviation ◽

Surface Temperature ◽

Water Temperature ◽

In Situ Measurements ◽

Thematic Mapper ◽

Landsat 8 ◽

Yukon River ◽

Daily Water Temperature ◽

Daily Water

Water temperature is a key element of freshwater ecological systems and a critical element within natural resource monitoring programs. In the absence of in situ measurements, remote sensing platforms can indirectly measure water temperature over time and space. The Earth Resources Observation and Science (EROS) Center has processed archived Landsat imagery into analysis ready data (ARD), including Level-2 Provisional Surface Temperature (pST) estimates derived from the Landsat 4–5 Thematic Mapper (TM), Landsat 7 Enhanced Thematic Mapper Plus (ETM+), and Landsat 8 Thermal Infrared Sensor (TIRS). We compared in situ measurements of water temperature within the Yukon River in Alaska with 52 instances of pST estimates between June 2014 and September 2020. Agreement was good with an RMSE of 2.25 °C and only a slight negative bias in the estimated mean daily water temperature of −0.47 °C. For the 52 dates compared, the average daily water temperature measured by the USGS streamgage was 11.3 °C with a standard deviation of 5.7 °C. The average daily pST estimate was 10.8 °C with a standard deviation of 6.1 °C. At least in the case of large unstratified rivers in Alaska, ARD pST can be used to infer water temperature in the absence of or in tandem with ground-based water temperature monitoring campaigns.

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