Seasonal pattern of the coastal fish assemblage in Anegada Bay, Argentina

Abstract

The seasonal variation of the inshore fish assemblage of Anegada Bay, North Patagonia, Argentina is described here. Three areas were seasonally sampled from 2007 to 2009 by means of a gang of bottom gill-nets. We found 21 coastal fish species, but species richness and fish number and weight changed throughout the year. The six species classified as dominant have national and regional value for artisanal and recreational fishing and were responsible for the seasonal variation in the fish assemblage. Both cluster and non-metric multidimensional scaling analyses based on fish number and fish weight indicated two major sample groups encompassing spring and summer (the warmer seasons) and autumn and winter (the colder seasons). The fish assemblage had higher species richness, dominance and abundance during the warmer seasons than during the colder seasons in the same years and at the same sites. Water temperature was the main environmental factor structuring the fish assemblage in Anegada Bay. We suggest that partial breeding migration toward the bay during warmer months could explain the seasonal pattern observed. Nevertheless, variation in temperature conditions agreed well with the pattern of seasonal changes, leading to an interaction between abiotic and biotic influences in determining the variability in this seasonal fish assemblage. We conclude that an understanding of species temporal and spatial patterns in areas of high ecological and economic value, as exemplified by Anegada Bay, are essential for the implementation of a management approach oriented toward ecosystem sustainability.

Biological and socio‐economic aspects of recreational fisheries and their implications for the management of coastal urban areas of south‐eastern Brazil

“…This percentage increases to 9.1% if the more comparable surface long-line catch of the Santos fleet (25 137 kg: http://www.pesca.sp.gov.br/estatistica) is included. These percentages may be underestimated because most of the hottest period of the year (October to March), when CPUE and effort is higher, was excluded from this study (Paiva Filho & Toscano 1987;FAO 2002a,b;Barreiros et al 2004;Godefroid et al 2004;Freire 2005aFreire , 2010Llompart et al 2012Llompart et al , 2013. Font and Lloret (2011) also found that recreational fishery yield was far below that of commercial fisheries in the NW Mediterranean.…”

“…; Freire , ; Llompart et al . , ). Font and Lloret () also found that recreational fishery yield was far below that of commercial fisheries in the NW Mediterranean.…”

A trans-ecosystem fishery: Environmental effects on the small-scale gillnet fishery along the Río de la Plata boundary

“…However, studies in the southwest Atlantic coastal system, e.g. San Blas Bay (Llompart et al, 2013) and marine coastal areas of Brazil (Pinheiro et al, 2009) found that the temporal variation in fish assemblages was mainly related to reproductive activities. Since the temporal pattern of fish species behavior in for a coastal region is influenced by both physical and biological conditions, it follows that these conditions must also influence the fishing calendar.…”

“…Although both fisheries captured the same coastal fish assemblage (Jaureguizar et al, 2006b;Llompart et al, 2013) and used the same net (90e120 mm), the RdP gillnet fishery landings were mostly based on Cynoscion guatucupa, Micropogonias furnieri, Mustelus schmitti and Parona signata, which represented 93% of spring landings composition, while in the San Blass gillnet fishery 96% of spring landings consisted of M. schmitti. This difference can be related to the high aggregation of this small shark during its mating and reproduction time, when adults enter the bay during spring and remain until the summer (Colautti et al, 2010).…”

Temperate fish community variation over seasons in relation to large-scale geographic seascape variables

“…Such information is critical for distinguishing between expected changes and anomalous conditions, as can be expected with a changing environment and climate (Molinos et al 2016). Much research has shown that fish assemblages vary over seasons, particularly in temperate coastal waters (e.g., Baden and Pihl 1984;Pihl and Wennhage 2002;Franco et al 2006;Baden et al 2012;Llompart et al 2013), and it is therefore expected that different assemblages will respond and be influenced differently to the surrounding environment. Fish shift locations for various reasons, such as ontogenetic migrations, which may be associated with feeding, spawning, and (or) nursery areas, or seasonal environmental fluctuations.…”