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The effects of recreational fishing on marine stocks and ecosystems have raised global concern in recent years. In Argentina, Southwest Atlantic, angling, netting and spearfishing of coastal bony fishes, sharks, rays and chimaeras are very popular pastime activities with more than 50 years of history. Despite the perceived traditional and economic relevance of these activities in the country, marine recreational fisheries were largely unregulated, and no official fisheries monitoring programs at the national level have been ever put in place. Except for a few particular systems for which some catch-and-effort data were collected by research institutions and non-governmental organizations, no comprehensive surveys aimed at describing the ecological, social or economic aspects of these fisheries have been made. Here, an updated review of the regulations in place for marine recreational fisheries along the Argentine coastline is presented. Of the five coastal provinces encompassing ca . 8400 km and about 20 latitude degrees (~36°S to 55°S) of coastline, only Buenos Aires province has a thorough legislation for its whole territory, which includes 15 protected areas. In the remaining provinces, the regulations for marine recreational fisheries are limited to a few protected areas (seven out of 37 coastal areas under provincial, national or shared jurisdiction). This lack of legislation encourages alleged recreational fishers to develop small-scale commercial fishing operations that are neither controlled nor monitored as such, contributing to the overexploitation of some key coastal stocks. [ABSTRACT FROM AUTHOR]

We investigated changes in the structure of coastal fish assemblages in Northern Patagonia, Southwestern Atlantic, by using baited remote underwater video stations (BRUVS) deployed at increasing distances from rocky reefs: 0–5 m, 15–20 m and 50–60 m. We estimated species richness and abundance (total and by preferred habitat type) and searched for diagnostic species in each distance range. We recorded 14 taxa across 11 families in 19 areas surveyed. Species richness and abundance were higher on reef ledges and decreased with distance from them, at a finer spatial scale than previously reported. Acanthistius patachonicus and Sebastes oculatus were indicative of reef ledges; they were less abundant at 15–20 m and disappeared at 50–60 m. Callorinchus callorynchus and Odontesthes spp. occurred only at distances >15–20 m from the reefs, while Galeorhinus galeus was distributed homogeneously throughout the surveyed area. Our findings have practical implications for monitoring ecotone demersal habitats with BRUVS. • Coastal fish assemblages were assessed with BRUVS. • Distance to rocky reefs affected the structure of fish assemblages in ecotone areas. • Major changes occurred at a fine spatial scale of about 15–20 m. • Results have practical implications for monitoring ecotone habitats with BRUVS. [ABSTRACT FROM AUTHOR]

Management of recreational fisheries may greatly benefit from accurate and precise estimates of catch and effort. The reliable estimation of recreational boat-fishing effort is particularly challenging due to the methodologies, logistics and high costs involved. Here, we propose a two-stage approach to estimate the number of boat-fishing trips based on an access-point survey developed for situations in which boaters often stay in the area for more than one day, making several fishing trips during their stay. The two-stage approach consists of, first, estimating the total number of boat-days for the fishing season, where boats present in the coast may potentially go fishing, and, second, estimating the probability that a boat present in the coast does go fishing on a given day. We illustrate the method by applying it to a recreational fishery targeting rocky-reef fishes in the San José Gulf, Península Valdés, Argentina. When used on simulated data the new method produced unbiased and more precise estimates of the number of boat-days compared to the traditional access-point survey method. Gains in precision varied depending on the number of survey visits, the survey schedule (random or regular visits) and the actual (simulated) number of boat-days. • We propose a two-stage novel approach to estimate recreational boat-fishing effort. • It was designed for boaters that often stay more than one day in the access-sites. • Information on the length of stays must be collected to apply the novel method. • A real-life case study and a simulation-estimation exercise are presented. • Estimates were unbiased and more precise than obtained with traditional methods. [ABSTRACT FROM AUTHOR]

Abstract: Several flexible methods for estimating tag loss rates through mark-resight data have been developed recently. They allow evaluation of different tag shedding modalities and relax the usual assumption of independence between the loss of tags made in classical double-tagging methods. Two conditions limit the applicability of these methods: (1) tagged individuals must have permanent marks so that they can still be identified after losing their tags, and (2) a large number of observations is required to obtain precise estimates. Here we evaluate the performance of alternative estimators of tag shedding rates when these conditions are not met, a situation that is very common in mark-resight experiments on reef fishes. We simulated resighting data using a simple exponential model of tag shedding under different scenarios created by varying the probabilities of fish detection and fish emigration from the reef, and the tagging schedule. The model was conditioned on actual data from a short-term (∼1.5 years) double-tagging study conducted on the Argentine sandperch Pseudopercis semifasciata (Cuvier 1829) in rocky reefs of northern Patagonia. We tested eight estimation procedures: three variants of an individual-based method, two based on a binomial likelihood function for exact or pooled times-at-liberty data, and three regression methods. Although the individual-based approach produced unbiased and most precise estimates when individuals that had lost both tags were identifiable, it performed poorly in the absence of permanent tags. In contrast, conditional methods, which do not require identification of individuals that have lost both tags, were more robust, providing unbiased and precise estimates. The pros and cons of the different methods for analyzing small-scale mark-resight experiments are discussed. [Copyright &y& Elsevier]

Abstract: We describe a new manual procedure for catching and tagging fish underwater, the ‘pole-hooking’ method, and demonstrate and discuss its advantages over standard tagging techniques (i.e. hook-and-line fishing). The new technique was designed for tagging Acanthistius brasilianus [Cuvier, M., Valenciennes, L.B., 1828. Histoire Naturelle des Poissons. Museau de Histoire Naturelle, Paris], a small to medium-sized fish inhabiting rocky reefs of the Argentine coast. The pole-hooking method minimizes injuries, avoids fast depressurization of fish and allows registration of the precise location of capture and release. In addition, the equipment needed is very simple and economical. The mean number of fish tagged per minute using this methodology on shallow rocky reefs (up to 25-m depth) was similar to that obtained during hook-and-line fishing sessions (ca. one tagged fish every 3min), given similar densities of A. brasilianus in the fished reefs. [Copyright &y& Elsevier]

We updated the distribution and habitat patterns of Maurolicus stehmanni in the Southwest Atlantic Ocean by compiling data obtained from research surveys conducted on the Argentinean continental shelf, as well as from opportunistic records. This paper confirms the presence of M. stehmanni in the Argentinean continental shelf, extending its southernmost distributional limit by ca. 1000 km (from 43.0°S to 52.2°S). Adult specimens of M. stehmanni were collected in various locations from 2004 to 2016. Eggs and larvae of Maurolicus spp. were caught during ichthyoplankton tows carried out from 2003 to 2013. The present paper furthermore extends the habitat type in which this species was recorded: specimens were found in the inner continental shelf (between 46.2°S and 52.2°S) instead of the shelf break and continental slope. Two specimens were found lying dead upon the beach of Puerto Madryn, Nuevo Gulf (42.8°S). The presence of eggs and larvae in coastal embayments (San Matías and San José gulfs), in concomitant occurrence with adults, may suggest the establishment of this species in the region. [ABSTRACT FROM AUTHOR]