A multi-model approach to evaluate the role of environmental variability and fishing pressure in sardine fisheries

Abstract

Please cite this article as: Leitão, F., Alms, V., Erzini, K., A multi-model approach to evaluate the role of environmental variability and fishing pressure in sardine fisheries, Journal of Marine Systems (2014Systems ( ), doi: 10.1016Systems ( /j.jmarsys.2014 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPTUnderstanding the fluctuations in population abundance is a central question in fisheries. Sardine fisheries are of great importance to Portugal and are data-rich and of primary concern to fisheries managers. In Portugal, sub-stocks of Sardine pilchardus (sardine) are found in different regions:the Northwest (IXaCN), Southwest (IXaCS) and the South coast (IXaS-Algarve). Each of these sardine sub-stocks is affected differently by a unique set of climate and ocean conditions, mainly during larval development and recruitment, which will consequently affect sardine fisheries in the short term. Taking this hypothesis into consideration we examined the effects of hydrographic (river discharge), sea surface temperature, wind driven phenomena, upwelling, and wind magnitude were negatively related with LPUE, revealing that environmental effects match with the regional peak in spawning time. Overall, results suggest that management of small, short-lived pelagic species, such as sardine quotas/sustainable yields, should be adapted to a regional scale because of regional environmental variability.

Time series analyses reveal environmental and fisheries controls on Atlantic horse mackerel (Trachurus trachurus) catch rates

“…However, UPW and wind driven events (VW-spring and WMAG-summer) relates with LPUE although with low probability. Results regarding the effect of wind over T. trachurus LPUE variability in summer and spring in Algarve are similar to those found for the European pilchard or sardine (sardina pilchardus), a small pelagic by Leitão et al (2014aLeitão et al ( , 2014b, using a similar statistical and methodological approach. The wind magnitude (WMag) is highest in summer, when calm sea conditions prevail; therefore the wind magnitude can be related to wind mixing, generating turbulence that leads to a nutrient input in surface waters (optimal environmental window hypothesis: Cury and Roy, 1989) enhancing plankton growth and better feeding conditions for fish larvae (Silva et al, 2006).…”

Study of sardine (Sardina pilchardus) regime shifts in the Iberian Atlantic shelf waters

“…More previous works have studied the relationship between environmental conditions and sardine dynamics in the Iberian shelf ecosystem (e.g., Santos et al., ; Garrido et al., ; Quattrocchi & Maynou, ; Malta, Santos, Santos, Rufino, & Silva, ; Leitão et al., ; Santos et al., , ; Borges, Santos, Crato, Mendes, & Mota, ). The originality of this study is that it employs a different methodology never used in this region before, takes into account the entire southern sardine stock and exploits an updated data series.…”

The effect of regional sea surface temperature rise on fisheries along the Portuguese Iberian Atlantic coast

“…Assessing and understanding climate change effects on fisheries is a major challenge for the sustainable management of marine ecosystems (Leitão, Alms, & Erzini, ). The distribution of marine fishes and invertebrates is strongly dependent on the physiological optima of species, as different species have different environmental preferences and tolerance limits (Pörtner & Farrell, ; Sunday, Bates, & Dulvy, ).…”