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The 1755 Lisbon earthquake, which reached a magnitude of 8.5, remains the most powerful and destructive to hit Europe so far. Within minutes, many lives were lost, populations displaced, livelihoods, homes and infrastructures were destroyed. Although frequently associated to the city of Lisbon, one of the most important European cities at the time, this earthquake caused similar damage and casualties, if not greater, in the southwest of the Algarve, where the seismic intensity was estimated at IX-X Mercalli Intensity Scale. Some time later a tsunami increased the number of victims and the amount of damage. In some locations the tsunami caused greater destruction than the earthquake itself. The tsunami hit both coasts of the North Atlantic; however, the more destructive damage occurred in the Portuguese coast, south from Lisbon, in the Gulf of Cadiz and in the Moroccan coast. The downtown of Lisbon was flooded by waves that reached a height of 6 m. The water flooded an area with an extension of around 250m from the coast. In the Southwest part of Algarve the waves reached a height between 10 and 15m and the flooded area was much larger. Through the analysis of recent research works on the assessment of the 1755 tsunami parameters and the interpretation of the more reliable historical documents, it is our intention to analyse the destructive power of the tsunami in the Algarve and delimit the flooded area. Using simple techniques of simulation it is our intention to assess the impacts nowadays of the occurrence of a tsunami similar to the one that hit the Algarve in 1755, which would probably affect a greater number of people, buildings and infrastructures. This assessment is an important instrument not only in terms of disaster preparedness but also for the integration of risk mitigation measures in land use planning. [ABSTRACT FROM AUTHOR]

Samples of Boops boops ranging from 7.4 to 30.5 cm were obtained mainly by longline, supplemented by beach seining in the Ria Formosa lagoon, and by market sampling in the Algarve (southern Portugal). The macroscopic analyses of the gonads and the gonad somatic index showed that the south coast of Portugal B. boops spawn mainly from late winter to spring, between February and May. The length at first maturity was similar for males and females and the value for both sexes combined was estimated to be 15.22 cm, corresponding to an age range of 1–3. Age was determined by reading growth bands on otoliths. Age determination was validated by marginal increment analysis. The estimated parameters were L∞ = 28.06, K = 0.22 and t0 = −1.42. Mortality rates were calculated for fish captured with longlines, and the estimated parameters were M = 0.33, Z = 1.04 and F = 0.71. Relative yield per recruit analysis and sensitivity analysis showed that the resource is moderately exploited. From the perspective of sustainability, these results provide support for the use of longlines as a gear that is among the least harmful for species such as the bogue. [ABSTRACT FROM AUTHOR]