title: Unshelled abalone and corrupted urchins: development of marine calcifiers in a changing ocean.
abstract: The most fragile skeletons produced by benthic marine calcifiers are those that larvae and juveniles make to support their bodies. Ocean warming, acidification, decreased carbonate saturation and their interactive effects are likely to impair skeletogenesis. Failure to produce skeleton in a changing ocean has negative implications for a diversity of marine species. We examined the interactive effects of warming and acidification on an abalone (Haliotis coccoradiata) and a sea urchin (Heliocidaris erythrogramma) reared from fertilization in temperature and pH/pCO(2) treatments in a climatically and regionally relevant setting. Exposure of ectodermal (abalone) and mesodermal (echinoid) calcifying systems to warming (+2°C to 4°C) and acidification (pH 7.6-7.8) resulted in unshelled larvae and abnormal juveniles. Haliotis development was most sensitive with no interaction between stressors. For Heliocidaris, the percentage of normal juveniles decreased in response to both stressors, although a +2°C warming diminished the negative effect of low pH. The number of spines produced decreased with increasing acidification/pCO(2), and the interactive effect between stressors indicated that a +2°C warming reduced the negative effects of low pH. At +4°C, the developmental thermal tolerance was breached. Our results show that projected near-future climate change will have deleterious effects on development with differences in vulnerability in the two species.
authors.affiliation: Schools of Medical Sciences, University of Sydney, New South Wales 2006, Australia. mbyrne@anatomy.usyd.edu.au
authors.forename: Maria
authors.initials: M
authors.lastname: Byrne
authors.forename: Melanie
authors.initials: M
authors.lastname: Ho
authors.forename: Eunice
authors.initials: E
authors.lastname: Wong
authors.forename: Natalie A
authors.initials: NA
authors.lastname: Soars
authors.forename: Paulina
authors.initials: P
authors.lastname: Selvakumaraswamy
authors.forename: Hannah
authors.initials: H
authors.lastname: Shepard-Brennand
authors.forename: Symon A
authors.initials: SA
authors.lastname: Dworjanyn
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Davis
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002113:Calcification, Physiologic / Q000502:physiology*; D002254:Carbonates / Q000032:analysis; D005306:Fertilization / Q000502:physiology; D049851:Gastropoda / Q000502:physiology*; D057232:Global Warming; D006863:Hydrogen-Ion Concentration; D009517:New South Wales; D009792:Oceans and Seas; D012617:Sea Urchins / Q000502:physiology*; D013045:Species Specificity; D013696:Temperature
chemical_list: D002254:Carbonates