Measuring Tailbeat Frequencies of Three Fish Species from Adaptive Resolution Imaging Sonar Data

Abstract

Imaging sonars, such as the Adaptive Resolution Imaging Sonar (ARIS), provide high-resolution sonar data that are used in fisheries research and management. While sonar methods have enormous potential for making population estimates, species identification via sonar remains an unresolved challenge. One method that may overcome this challenge involves measuring tailbeat frequencies to guide species differentiation. The tailbeat frequencies of three commonly sympatric anadromous fish species of eastern North America, Atlantic Salmon Salmo salar, Striped Bass Morone saxatilis, and American Shad Alosa sapidissima, were measured from imaging sonar data collected in an experimental low-flow, short-range setup. The frequencies were significantly different between the species (mean ± 1 SD beats/s: 0.6 ± 0.3 [Atlantic Salmon], 0.9 ± 0.2 [Striped Bass], and 1.4 ± 0.3 [American Shad]) when measured using a previously established manual method. Building on this, an automated method was developed and tested, and the method showed promising results. However, when compared to manually identified number of beats the error was large (on average, 1.1 [Atlantic Salmon], 4.8 [Striped Bass], and −0.4 [American Shad] beats in a fish track), especially in high fish densities. Despite the limitations, the automated method has utility in fisheries management when high-quality data can be collected for species with differing tailbeat frequencies.

Observing fish interactions with marine energy turbines using acoustic cameras

“…Able et al, 2014; Egg et al, 2017; Helminen et al, 2020; Kang, 2011; Mueller et al, 2010; Parsons et al, 2017). Helminen et al (2021) and Mueller et al (2010) demonstrated the potential of this approach and successfully calculated tail beat frequencies from data collected using an ARIS and DIDSON respectively. However, the utility of this technique is likely to change between sites because fish may alter their behaviour in different environments (Helminen et al, 2021) and background noise levels will affect the ability to discern tail beats (Mueller et al, 2010).…”

“…stands in contrast with taxonomic classification of fishes in optical camera imagery, where classification can often be performed based on a single image. Several studies have proposed the use of tail beat frequency as a quantitative behavioural metric that may aid in classification (e.g Able et al, 2014;Egg et al, 2017;Helminen et al, 2020;Kang, 2011;Mueller et al, 2010;Parsons et al, 2017). Helminen et al (2021.…”

Monitoring fish using imaging sonar: Capacity, challenges and future perspective

“…However, the tailbeat frequency generally overlaps among different species. Other features such as migrating time and shape should be combined (Helminen et al, 2021). The feature‐based methods are straightforward for species identification, but the reported morphological and motion features are not good enough to distinguish similar fishes.…”

Combining Imaging Sonar Counting and Underwater Camera Species Apportioning to Estimate the Number of Atlantic Salmon and Striped Bass in the Miramichi River, New Brunswick, Canada

“…2014; Helminen et al. 2021; Helminen and Linnansaari 2021). They can remain operational over a broader range of stream conditions (e.g., high‐flow periods) compared to weir counting (Pipal et al.…”

“…2020; Helminen et al. 2021). Combining sonar with other methods, such as fishing or underwater video cameras (UWCs), is used to estimate the abundance of each species in fixed‐location sonar applications within rivers (Mueller et al.…”