Nurturant behavior toward dead conspecifics has been documented in several free-ranging marine and terrestrial mammals but still remains undocumented and poorly understood for most species. This study describes observations of adults carrying dead calves and juveniles in 7 odontocetes (toothed cetaceans) species and discusses the subject in mammals in general. Observations are based on 14 events from 3 oceans and constitute the 1st records for Indo-Pacific bottlenose dolphins ( Tursiops aduncus ), spinner dolphins ( Stenella longirostris ), killer whales ( Orcinus orca ), Australian humpback dolphins ( Sousa sahulensis ), and sperm whales ( Physeter macrocephalus ), as well as presenting additional records for Risso’s dolphins ( Grampus griseus ) and short-finned pilot whales ( Globicephala macrorhynchus ). Information on how the adults supported and carried the dead conspecifics, on the gender of both adults and dead young, and on the age class of the dead young, is presented. Moreover, a comparison with terrestrial mammals, including a compilation of published literature, and a discussion on possible hypotheses to explain this particular type of behavior are given. The present study helps to corroborate that adults mourning their dead young is a common and globally widespread behavior in long-lived and highly sociable/cohesive species of mammals.

This study describes sea urchin spatial distribution in relation to environmental factors, and the relationship between Diadema antillarum density and algal abundance. Twenty-three transects around Madeira Island were surveyed by scuba divers, and sea urchin density and algal cover were determined in situ. Sampling sites along these transects were characterised in terms of distance from the tide line, water depth, substratum type, bottom declivity and water turbulence. Diadema antillarum was the dominant sea urchin species. Paracentrotus lividus and Arbacia lixula occurred at shallower depths (2-6 m), contrasting with the distribution of Sphaerechinus granularis, which occurs among D. antillarum (4-20 m). Surveys found two alternative types of communities on rocky shores: 1) a community with high algal cover and low numbers of sea urchins, along the north and south-west coasts and; 2) a community with little algal cover and high densities of sea urchins, along the south-east coast. Macroalgal cover and D. antillarum densities were inversely correlated (adjusted R2=75.6%; n = 429; p< 0.05). The results showed that water turbulence was the most important factor limiting the distribution of D. antillarum on rocky substrates. We propose a multiple non-linear regression model (using backward stepwise analysis) to explain D. antillarum abundance on the rocky shores: D. antillarum/m2 (??)= 0.121 - 0.209 distance from shore (in m) (??) + 2.052 water depth (in m) (??) - 1.778 water turbulence level (??) - 0.007 water turbulence level4 (??); where ?? indicates data are square-root transformed (adjusted R2 = 60.99%; n = 454; p< 0.05).