The incidental mortality of albatrosses Diomedeidae and petrels Procellariidae by longline fishing vessels, has been assessed and analysed in several areas of the globe. We provide the first direct estimates of incidental mortality rates of albatrosses and petrels along the Argentine Shelf and shelf break. The estimated by-catch rate for the whole period analysed (1999-2001) was 0.04 birds/1,000 hooks, with a maximum of 0.20 birds/1,000 hooks observed in 1999. Annual captures averaged 1,160 birds; however, the large variation observed indicates that annual by-catch may be in the order of thousands, with around 10,000 seabirds being killed by longliners through the study period. Most of the captures were observed along the Patagonian shelf break. At least 12 bird species were incidentally taken, with Black-browed Albatrosses Thalassarche melanophris and White-chinned Petrels Procellaria aequinoctialis accounting for about 80% of total captures. The information provided in this study allowed the design and future implementation of mitigation measures and new survey methods onboard longliners operating in Atlantic waters on the Argentine shelf.

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Considering the evolution of aeolian to marine transitions for the geological record, either catastrophic or gradual transgressive scenarios showing high or low rates of coastal migration have been proposed. A critical evaluation of modern analogues suggests that a catastrophic transgression shares many characteristics with Holocene transgressions, yet they are caused by different rates of sea-level rise. The present study provides insights into the evolution of aeolian to marine transitions in order to discuss these alternative scenarios of sea-level rise. For this purpose, a sedimentological and ichnological analysis was carried out on ten stratigraphic sections of the Pic un Leuf u area, Argentina. There, marine deposits of the Vaca Muerta Formation accumulated over the aeolian deposits of the Quebrada del Sapo Formation during the early Tithonian. The sedimentary evolution of the transition can be summarized in: (i) a shutdown of aeolian dune field deposition, generating a planation surface in somewhat elevated areas and reworked megadunes in lowlands; (ii) beach sedimentation caused by episodic marine flooding that contributed to megadune reworking; and (iii) deposition in an embayed marginal-marine setting at the coast, recorded by bay margin bindstone, proximal bay and distal bay sedimentation. This transition indicates very rapid coastline migration and a condensed Transgressive Systems Tract succession throughout the study area. Rates of sea-level rise similar to Holocene ones (millimetres to centimetres per year) may have produced the transition between the Quebrada del Sapo and Vaca Muerta formations. The Late Jurassic represents a non-glacial time, and the global sea-level maximum highstand pre-dated the Vaca Muerta 2732