Aggressiveness-related behavioural types in the pearly razorfish

Abstract

Behavioural types (i.e., personalities or temperament) are defined as among individual differences in behavioural traits that are consistent over time and ecological contexts. Behavioural types are widespread in nature and play a relevant role in many ecological and evolutionary processes. In this work, we studied for the first time the consistency of individual aggressiveness in the pearly razorfish, Xyrichtys novacula, using a mirror test: a classic method to define aggressive behavioural types. The experiments were carried out in semi-natural behavioural arenas and monitored through a novel Raspberry Pi-based recording system. The experimental set up allowed us to obtain repeated measures of individual aggressivity scores during four consecutive days. The decomposition of the phenotypic variance revealed a significant repeatability score (R) of 0.57 [0.44–0.60], suggesting high predictability of individual behavioural variation and the existence of different behavioural types. Aggressive behavioural types emerged irrespective of body size, sex and the internal condition of the individual. Razorfishes are a ubiquitous group of fish species that occupy sedimentary habitats in most shallow waters of temperate and tropical seas. These species are known for forming strong social structures and playing a relevant role in ecosystem functioning. Therefore, our work provides novel insight into an individual behavioural component that may play a role in poorly known ecological and evolutionary processes occurring in this species.

Measuring inter-individual differences in behavioural types of gilthead seabreams in the laboratory using deep learning

“…Nevertheless, this was not the main reason for switching to a deep learning approach, as the efficiency of a well-implemented traditional CV tracking algorithm was not questioned. However, the following set of experimental trails in the behavioural arenas required for another fish species ( Xyrichtys novacula ), applying changing light conditions (experiments on circadian rhythms and chronotypes require day and night light cycles) and presenting new objects ( Martorell-Barceló et al, 2021 ). Under these circumstances, we decided it was more advantageous for our research to train another neural network than having to manually readjust a CV algorithm.…”

Broad‐scale applications of the Raspberry Pi: A review and guide for biologists

“…Martorell‐Barceló et al. (2021) filmed individual fish continuously over multiple days to investigate the repeatability of aggressive behaviour, which they extended with deep learning to detect fish automatically over long periods of time (Signaroli, 2020). To further investigate the emergence of individual behavioural types, Laskowski, Jolles et al (pers.…”

“…Lertvilai (2020) built an automated recording device specifically for autonomous zooplankton surveys in the wild. And Hermann et al (2020) developed F I G U R E 3 A diverse range of Raspberry Pi applications: (a) plant phenotyping(Tausen et al, 2020), (b) high-throughput animal recordings(Jolles et al, 2017), (c) a dedicated plant growth cabinet(Ghosh et al, 2018), (d) a 3D-printed microscope (FlyPi; MaiaChagas et al, 2017), (e) an RFID-equipped birdfeeder(Youngblood, 2020), f) long-term monitoring of fish behaviour(Martorell-Barceló et al, 2021), (g) automated bird puzzle boxes(Chimento et al, 2021), (h) an autonomous underwater camera system(Lertvilai, 2020), (i) automated quantification of fly climbing behaviour(Spierer et al, 2021), (j) a field audio recorder for bioacoustics(Bradfer-Lawrence et al, 2019;Whytock & Christie, 2017), (k) an operant conditioning device for wild mesocarnivores(Stanton et al, 2020), (l) autonomous ecosystem monitoring(Sethi et al, 2018), (m) closed-loop virtual reality(Tadres & Louis, 2020), (n) long-term recording of fish from birth (K. Laskowski & J. Jolles, pers. comm.…”

Disparate behavioral types in wild and reared juveniles of gilthead seabream

“…In our study, a mirror was placed in contact with one side of the behavioral arena, simulating the presence of a conspeci c at close range (Table 1). We measured the number of aggressive and hostile "approaches" the sh gave to the mirror per hour by manually visualizing the videos 24,38 .…”

“…Many of the causes and consequences of sh BTs have been studied on freshwater shes, mainly on zebra sh, Danio rerio 17 , three-spined stickleback, G. aculeatus 18 , and guppy, Poecilia reticulata 19 . In marine species, consistency in individual behavior has been reported, for example, for two-spotted goby, Gobiusculus avescens 20 , gilthead seabream, Sparus aurata 21 , European seabass, Dicentrarchus labrax 22 and pearly razor sh, Xyrichtys novacula 23,24 . In this study, we examine the degree of consistency of individual behavior in wild and reared samples of juvenile gilthead seabreams.…”