Middle fins hold the key to fish movement

AbstractMotorboat noise is recognized as a major source of marine pollution, however little is known about its ecological consequences on coastal systems. We developed a State Space Model (SSM) that incorporates an explicit dependency on motorboat noise to derive its effects on the movement of resident fish that transition between two behavioural states (swimming vs. hidden). To explore the performance of our model, we carried out an experiment where free-living Serranus scriba were tracked with acoustic tags, while motorboat noise was simultaneously recorded. We fitted the generated tracking and noise data into our SSM and explored if the noise generated by motorboats passing at close range affected the movement pattern and the probability of transition between the two states using a Bayesian approach. Our results suggest high among individual variability in movement patterns and transition between states, as well as in fish response to the presence of passing motorboats. These findings suggest that the effects of motorboat noise on fish movement are complex and require the precise monitoring of large numbers of individuals. Our SSM provides a methodology to address such complexity and can be used for future investigations to study the effects of noise pollution on marine fish.

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Wireless logging of extracellular neuronal activity in the telencephalon of free-swimming salmonids

Animal Biotelemetry ◽

10.1186/s40317-021-00232-4 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Susumu Takahashi ◽

Takumi Hombe ◽

Riku Takahashi ◽

Kaoru Ide ◽

Shinichiro Okamoto ◽

...

Keyword(s):

Neuronal Activity ◽

Environmental Cues ◽

Fish Movement ◽

Water Tank ◽

Head Direction ◽

Free Swimming ◽

Rodent Brain ◽

River Migration ◽

Spike Waveforms ◽

The Brain

Abstract Background Salmonids return to the river where they were born in a phenomenon known as mother-river migration. The underpinning of migration has been extensively examined, particularly regarding the behavioral correlations of external environmental cues such as the scent of the mother-river and geomagnetic compass. However, neuronal underpinning remains elusive, as there have been no biologging techniques suited to monitor neuronal activity in the brain of large free-swimming fish. In this study, we developed a wireless biologging system to record extracellular neuronal activity in the brains of free-swimming salmonids. Results Using this system, we recorded multiple neuronal activities from the telencephalon of trout swimming in a rectangular water tank. As proof of principle, we examined the activity statistics for extracellular spike waveforms and timing. We found cells firing maximally in response to a specific head direction, similar to the head direction cells found in the rodent brain. The results of our study suggest that the recorded signals originate from neurons. Conclusions We anticipate that our biologging system will facilitate a more detailed investigation into the neural underpinning of fish movement using internally generated information, including responses to external cues.

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Thresholds in seascape connectivity: influence of mobility, habitat distribution, and current strength on fish movement

Landscape Ecology ◽

10.1007/s10980-013-9930-9 ◽

2013 ◽

Vol 28 (10) ◽

pp. 1937-1948 ◽

Cited By ~ 18

Author(s):

Iain R. Caldwell ◽

Sarah E. Gergel

Keyword(s):

Current Strength ◽

Fish Movement ◽

Habitat Distribution

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Culverts in paved roads as suitable passages for Neotropical fish species

Neotropical Ichthyology ◽

10.1590/s1679-62252012000400009 ◽

2012 ◽

Vol 10 (4) ◽

pp. 763-770 ◽

Cited By ~ 7

Author(s):

Sergio Makrakis ◽

Theodore Castro-Santos ◽

Maristela Cavicchioli Makrakis ◽

Ricardo Luiz Wagner ◽

Maurício Spagnolo Adames

Keyword(s):

Fish Passage ◽

Fish Movement ◽

Upstream Migration ◽

Migratory Species ◽

Neotropical Fish ◽

Potential Barriers ◽

Medium Risk ◽

Fall Height ◽

Additional Monitoring ◽

Spawning Success

Improperly installed or poorly maintained culverts can pose a serious threat to fish by disrupting their habitat and endangering spawning success. Road culverts that are not designed for fish passage frequently can become obstacles. This can be especially problematic for migratory species, but can lead to fragmentation of resident populations as well. This study evaluated 40 culverts of 29 sites within a 25-km radius from Toledo city, Paraná State, southern Brazil, with respect to their likely effects on movement of the local ichthyofauna. We collected data on the shape and length of culverts, culvert material, waterfall height, water column depth, slope, and estimated flow velocity. Culverts were categorized by level of barrier risk for upstream migration: high, medium, low, and impassable, as well as the type of barrier posed (fall height, depth, length and velocity). Most of culverts analyzed were considered potential barriers to fish movement, with 45% classified as impassible, 45% as high risk, 10% as medium risk, and no culverts as low risk. Brazilian culverts as fishways will require additional monitoring and studies to corroborate the premises proposed in the present study. Road culvert projects that are properly built and maintained will be able to simultaneously improve function of roadways and protect fish populations.

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Fish Movement and Weir Drown-Out

World Environmental and Water Resources Congress 2010 ◽

10.1061/41114(371)156 ◽

2010 ◽

Author(s):

Robert Keller

Keyword(s):

Fish Movement

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Modified Staaland Device with Automatic Recording Techniques for Determining Salinity Preference in Fishes

Journal of the Fisheries Research Board of Canada ◽

10.1139/f78-147 ◽

1978 ◽

Vol 35 (6) ◽

pp. 910-912 ◽

Cited By ~ 8

Author(s):

Albert J. Fivizzani ◽

Richard E. Spieler

Keyword(s):

Key Words ◽

Direct Observation ◽

Continuous Monitoring ◽

Automatic Recording ◽

Fish Movement ◽

Photographic Recording ◽

Salinity Preference ◽

Fish Activity ◽

Made In ◽

Recording Techniques

Modifications were made in the design and filling procedure of the Staaland device used to study salinity preference in fish. Two photographic recording techniques that eliminate the need for direct observation of fish activity and allow for continuous monitoring of fish movement throughout several daily photoperiodic cycles are described. Key words: salinity, preference, gradient, fish, photography, recording

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Comparison of sonar-, camera- and net-based methods in detecting riverine fish-movement patterns

Marine and Freshwater Research ◽

10.1071/mf18068 ◽

2018 ◽

Vol 69 (12) ◽

pp. 1905 ◽

Cited By ~ 6

Author(s):

Leonhard Egg ◽

Joachim Pander ◽

Melanie Mueller ◽

Juergen Geist

Keyword(s):

Species Identification ◽

Detection Rate ◽

Small River ◽

Monitoring Data ◽

Fish Movement ◽

Clear Water ◽

Camera System ◽

Riverine Fish ◽

Number Of Individuals ◽

Fish Monitoring

Monitoring of fish movement is important in understanding and optimising the functionality of fishways and in restoring riverine connectivity. This study compared fish monitoring data (ARIS sonar-based and GoPro camera-based), with catches in a multi-mesh stow net following downstream passage in a small river in Bavaria, Germany. In terms of the number of individuals, the sonar-based system (detection rate=62.6% of net-based catches) outnumbered the counts of the camera-based system (45.4%). Smaller specimens of <100 and <150mm were under-represented with the sonar and the camera-based systems respectively. Species identification based on the camera system was similar to that for net-based catch, whereas no proper species identification could be performed with sonar data. In conclusion, the sonar-based system can be recommended for the counting of fish >100mm during night and turbid conditions, unless species identification is necessary. During daylight and with clear water, cameras can be a cheaper and promising option to monitor species compositions of fish >150mm.

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