An investigation on body displacement after two drowning accidents

Habitat preference of mosasaurs indicated by rare earth element (REE) content of fossils from the Upper Cretaceous marine deposits of Alabama, New Jersey, and South Dakota (USA)

“…In a marine environment, some individuals, especially those with high body fat content in very shallow water (Reisdorf et al, 2012), may become buoyant with post mortem decompositional gasses and be transported by water or air currents to exotic locations well away from their typical habitat before burial. However, these 'bloat and f loat' individuals are here assumed to be exceptional rather than the standard and most specimens are preserved in or near their preferred habitat (Reisdorf et al, 2012;Mateus et al, 2013). Once buried in marine sediment, the preserved skeletal remains begin to assimilate REEs located in the surrounding labile sediment and pore waters during the early stages of diagenesis (Trueman & Benton, 1997;Trueman, 1999).…”

When Tragedy Strikes: Potential Contributions From Ocean Observation to Search and Rescue Operations After Drowning Accidents

“…Each drowning accident is unique and has different outcomes, even when victims are physiologically similar (e.g., the same age, size, and gender) and have drowned simultaneously and at the same spot (Mateus and Vieira, 2014). However, the post-drowning processes that control the decomposition of the body are known and allow to predict the basic patterns of the body vertical and horizontal displacement (Mateus et al, 2013). Based on empirical evidence, we propose four distinct stages for the post-drowning period (Figure 1), each characterized by rather different interactions between the body and its surroundings.…”

“…The hydrodynamics of the site will determine if gravitational and frictional forces overcome drag forces by the current, in which case the horizontal displacement of the body is significantly reduced. Depending on the water temperature, the PMSI can range from a few days, up to a few weeks (Giertsen and Morild, 1989;Mateus et al, 2013;Mateus and Vieira, 2014). In this stage, authorities in charge of the SAR should allow time to pass without significant intervention.…”

“…If dislodged from rocks, caves, branches, etc., the body will eventually regain buoyancy and resurface, ending the PMSI, becoming visible. The timing of this event can be estimated by SAR units, based on the calculation of accumulated degree days (ADD) (Megyesi et al, 2005;Mateus et al, 2013;Mateus and Vieira, 2014;Mateus and Pinto, 2016). An active search must then be resumed, but in a significantly larger radius than in Stage 1, aiming to spot the body as soon as possible after resurfacing, thus preventing significant drift due to waves or stronger surface currents.…”

“…From an empiric perspective, this commitment is frequently inefficient. Once a body disappears at sea, it is either lost or eventually found after resurfacing (Duijst et al, 2016), which can take place in a period ranging from a few days up to several months (Giertsen and Morild, 1989;Mateus et al, 2013;Mateus and Vieira, 2014;Mateus and Pinto, 2016). Standard SAR protocols are characterized by intense search efforts during the first few days, frequently followed by regular, less intensive, scouting from land, sea or air over the following days (Stoop, 2003).…”