European seabass show variable responses in their group swimming features after tag implantation

Abstract

The usefulness of acoustic telemetry on the study of movements, interactions, and behaviors has been revealed by many field and laboratory studies. The process of attaching acoustic tags on fish can, however, impact their physiological, behavioral, and growth performance traits. The potential negative effects are still unknown for several species and behavioral attributes. Previous studies have attempted to shed light on the effects of tag implantation on fish, focusing mainly on fish growth and physiological parameters, and one or two behavioral properties mainly on the individual level. However, the effect of this procedure could also be expressed at the group level. This study investigated the short-term effects of dummy and active body-implanted acoustic tags on the group-level swimming performance of adult European seabass (Dicentrarchus labrax) using optical flow analysis. We studied four main swimming performance properties-group speed, alignment (polarization), cohesion, and exploratory behavior. To help in the interpretation of any detected differences, physiological stress-related parameters were also extracted. The results show that the tag implantation procedure has variable effects on the different swimming performance attributes of fish. Group cohesion, polarization, and the group's exploratory tendency were significantly impacted initially, and the effect persisted but to a lesser extent two weeks after surgery. In contrast, group speed was not affected initially but showed a significant decrease in comparison with the control group two weeks postsurgery. In addition, the physiological parameters tested did not show any significant difference between the control and the treated group 14 days after the onset of the experiment. The findings suggest that the effect of tagging is non-trivial, leading to responses and response times that could affect behavioral studies carried out using acoustic telemetry.

Survival and swimming performance of a small-sized Cypriniformes (<em>Telestes muticellus</em>) tagged with passive integrated transponders

“…The partially different results of our study might be due to interspecific differences (Brown et al, 2006), perhaps in combination with study-specific effects (e.g., sample size, variability, test design). It is possible that longer recuperation after tagging would reduce or even erase the difference between tagged and untagged fish (Adams et al, 1998;Georgopoulou et al, 2022). We studied the swimming performance 22-23 days after tagging, allowing a relatively short time for the fish to recover.…”

“…Although it is likely that for relatively stationary small stream fish, the maximum swimming speed achieved is at least of the same, if not higher, importance as the capability of steady swimming for several minutes (Domenici, 2010;Starrs et al 2011). It is also likely that the tagging effect on prolonged swimming performance will decline with time (Adams et al, 1998;Georgopoulou et al, 2022). The importance of potential reduced prolonged swimming capacity on the study results needs to be weighted on a study-by-study basis.…”

Growth performance, gut microbiota composition, health and welfare of European sea bass (Dicentrarchus labrax) fed an environmentally and economically sustainable low marine protein diet in sea cages

“…That could be due to our protocol in which, following the surgical procedure, tagged fish were kept three days in tanks, away from sea cages stressors (high density, competition), to ensure recovery before being reintroduced into sea cages. In addition, the implantation of tag was demonstrated to not induce stress in sea bass by monitoring different endpoints (e.g., growth, cortisol, MO 2 ) 30 , 82 but it is worth mentioning that some behavioral alterations (group cohesion, polarization) may be observed following tagging 83 . In this trial, we continuously monitored the acceleration of sea bass fed with the two different diets over a two-months period.…”

Food anticipatory behaviour on European seabass in sea cages: activity-, positioning-, and density-based approaches

“…The three receivers were submerged in the floating ring of the sea cage with the help of ropes to a depth of 2.5 m. The GPS positions in decimal degrees (N, E) formed a triangle: (35:48011, 24:112), (35:48006, 24:11209), and (35:48, 24:11196). The acoustic tags used for implantation were low-power transmitters (ADT-LP7, Thelma Biotel Ltd.) with the following specifications from the producer: a diameter of 7.3 mm, a length of 23.2 mm, a weight in the air/water of 2.1 g/1.1 g (1.8 g measured weight in water in Georgopoulou et al, 2022), and a power output of 139 dB. The signal interval for depth is every 30-90 s (mean 60 s), and alternately, temperature or activity (mean 120 s).…”