Dolphin pods exhibit this behavior within their feeding areas in the wild.  Mann and Watson-Capps (2005) report that mothers foraging behavior are likely during separations with their calves. Most calf mortalities happen when poor calf condition is directly affected by the maternal condition and experience during the weaning and nursing process.  Since observations of this behavior are often seen by whale watchers in feeding areas, it is possible that tourism may have disrupted the foraging of mothers, decreasing their maternal condition, resulting in poor calf conditions or even death.
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 Ritter, F. (2007) Behavioural responses of rough-toothed dolphins to a dead newborn calf. Marine Mammal Science 23(2):429-433.
 Caldwell, M.C.; Caldwell, D.K. (1966) Epimeletic (care-giving) behavior in Cetacea. Pp. 755-789 In K.S. Norris (ed) Whales, dolphins and porpoises.
 Harzen, S.; Dos Santos, M.E. (1992) Three encounters with wild bottlenose dolphin (Tursiops truncatus) carrying dead calves. Aquatic Mammals 18:49-55.
 Mann, J.; Watson-Capps, J.J. (2005) Surviving at sea: ecological and behavioural predictors of calf mortality in Indian Ocean bottlenose dolphins, Tursiops sp. Animal Behaviour 69(4):899-909.