Pelagic fish assemblages assessed using mid-water baited video: standardising fish counts using bait plume size

Heagney, Elizabeth; Lynch, Tim; Babcock, Russell C.; Suthers, Iain M.

doi:10.3354/meps07193

Cited by 92 publications

(70 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In many places around the world, underwater video has become a common approach to monitor the abundance and distribution of marine fish and invertebrate species and to quantify marine biodiversity (e.g., Heagney et al, 2007;Stobart et al, 2007;Brooks et al, 2011;Merritt et al, 2011;Gladstone et al, 2012). For many such studies, BRUVS have been used and have provided an index of the abundance of various species through the use of a stationary point-count with the MinCount method (Ellis and DeMartini, 1995;Murphy and Jenkins, 2010).…”

Section: Discussionmentioning

confidence: 99%

Estimating relative abundance and species richness from video surveys of reef fishes

Bacheler¹,

Shertzer²

2014

View full text Add to dashboard Cite

Abstract-Underwater video sampling has become a common approach to index fish abundance and diversity, but little has been published on determining how much video to read. We used video data collected over a period of 6 years in the Gulf of Mexico to examine how the number of video frames read affects accuracy and precision of fish counts and estimates of species richness. To examine fish counts, we focused on case studies of red snapper (Lutjanus campechanus), vermilion snapper (Rhomboplites aurorubens), and scamp (Mycteroperca phenax). Using a bootstrap framework, we found that fish counts were unbiased when at least 5 of 1201 video frames within a 20-min video were read. The relative patterns of coefficients of variation (CVs) were nearly identical among species and declined as an inverse power function. Initial decreases in CVs were rapid as the number of frames read increased from 1 to 50. However, subsequent declines were modest, decreasing only by ~50% when the number of frames read increased by 300%. Estimated species richness increased asymptotically as the number of frames read increased from 25 to 200 frames, and reading 50 frames documented 86% of the species observed across all 1201 frames. Lastly, we used a generalized additive model to show that the most likely species to be missed were fast-swimming fishes that are solitary or form relatively small schools. Our results indicate that the most efficient use of resources (i.e., maximum information gained at the lowest cost) would be to read ~50 frames from each video.

show abstract

Section: Discussionmentioning

confidence: 99%

Estimating relative abundance and species richness from video surveys of reef fishes

Bacheler¹,

Shertzer²

2014

View full text Add to dashboard Cite

show abstract

“…However, reliable data on pelagic fishes is hard to obtain due to high spatiotemporal variability in their distribution and abundance, and ability to avoid survey equipment (Freon and Misund 1999). Different field methods (rather than underwater visual census or experimental fishing) would be needed to conduct rigorous assessments of pelagic fish populations, including novel techniques such as mid-water baited remote underwater video (Heagney et al 2007). …”

Section: Discussionmentioning

confidence: 99%

Marine reserves: Fish life history and ecological traits matter

Claudet

Osenberg

Domenici

et al. 2010

Ecological Applications

252

228

View full text Add to dashboard Cite

Abstract. Marine reserves are assumed to protect a wide range of species from deleterious effects stemming from exploitation. However, some species, due to their ecological characteristics, may not respond positively to protection. Very little is known about the effects of life history and ecological traits (e.g., mobility, growth, and habitat) on responses of fish species to marine reserves. Using 40 data sets from 12 European marine reserves, we show that there is significant variation in the response of different species of fish to protection and that this heterogeneity can be explained, in part, by differences in their traits. Densities of targeted sizeclasses of commercial species were greater in protected than unprotected areas. This effect of protection increased as the maximum body size of the targeted species increased, and it was greater for species that were not obligate schoolers. However, contrary to previous theoretical findings, even mobile species with wide home ranges benefited from protection: the effect of protection was at least as strong for mobile species as it was for sedentary ones. Noncommercial bycatch and unexploited species rarely responded to protection, and when they did (in the case of unexploited bentho-pelagic species), they exhibited the opposite response: their densities were lower inside reserves. The use of marine reserves for marine conservation and fisheries management implies that they should ensure protection for a wide range of species with different life-history and ecological traits. Our results suggest this is not the case, and instead that effects vary with economic value, body size, habitat, depth range, and schooling behavior.

show abstract

“…The maximum abundance observed in either of the 2 revolutions was used, as is typical in baited remote underwater video (BRUV) studies (e.g. Heagney et al 2007).…”

Section: Methodsmentioning

confidence: 99%

Coastal salmon farms attract large and persistent aggregations of wild fish: an ecosystem effect

Dempster

Uglem²,

Sánchez-Jérez³

et al. 2009

Mar. Ecol. Prog. Ser.

149

143

View full text Add to dashboard Cite

Coastal aquaculture is a globally expanding enterprise. Currently, 1200 salmon farms operate in coastal Norway, yet their capacity to aggregate and subsequently modify wild fish distributions is poorly known. Aggregations of wild fish at 9 farms and 9 control locations were counted on 3 separate days in June to August 2007. On each sampling occasion, 6 counts were made at 5 distinct depth-strata at each farm and control location. Wild fish were 1 to 3 orders of magnitude more abundant at farms than at control sites, depending on the location. Gadoid fish (Pollachius virens, Gadus morhua and Melanogrammus aeglefinus) dominated farm-associated assemblages and were present across a wide range of sizes, from juveniles to large adults. Estimated total farmaggregated wild fish biomass averaged 10.2 metric tonnes (t) per farm across the 9 farms (range: 600 kg to 41.6 t). Applied across the geographical range of Norway's 1200 salmon farms, our estimates indicate that salmon farms attract and aggregate over 12 000 t of wild fish into a total of just 750 ha of coastal waters on any given day in summer. Possible consequences of these persistent, substantial aggregations of wild fishes at farms include a heightened potential for the transfer of pathogens from salmon farms to wild fish and among adjacent salmon farms, and altered availability of wild fish to fisheries. Restrictions on fishing in the immediate surrounds of salmon farms may avoid farms acting as ecological traps, particularly for species with depressed populations such as G. morhua, which are highly attracted to farms.

show abstract

Pelagic fish assemblages assessed using mid-water baited video: standardising fish counts using bait plume size

Cited by 92 publications

References 54 publications

Estimating relative abundance and species richness from video surveys of reef fishes

Estimating relative abundance and species richness from video surveys of reef fishes

Marine reserves: Fish life history and ecological traits matter

Coastal salmon farms attract large and persistent aggregations of wild fish: an ecosystem effect

Contact Info

Product

Resources

About