Influence of temperature and spawning effort on Haliotis tuberculata mortalities caused by Vibrio harveyi: an example of emerging vibriosis linked to global warming

Abstract

Since 1998, Haliotis tuberculata mass mortalities have been occurring regularly in wild abalone populations in France during their reproductive period and in conjunction with seawater summer temperature maxima and Vibrio harveyi presence. To confirm the importance of bacterial exposure, temperature and reproductive status on abalone susceptibility, experimental infections via bath exposure were performed using abalone ranging from immature to reproductively mature. Ripe abalone were more susceptible to the bacterium than immature specimens (Po0.001), and a difference of only 1 1C in temperature had a highly significant impact on the mortalities (Po0.001). The natural mortalities that were surveyed during summer 2007 confirmed that recent epidemic losses of European abalone appeared in conjunction with host reproductive stress, elevated temperatures and presence of the pathogen V. harveyi. In view of the elevation of the mean summer temperatures observed in Brittany and Normandy over the last 25 years, this temperature-dependent vibriosis represents a new case of emerging disease associated with global warming.

Unshelled abalone and corrupted urchins: development of marine calcifiers in a changing ocean

“…Calcification in bivalve veligers is less sensitive to acidification than seen here for H. coccoradiata. If larvae of other Haliotis species are similarly sensitive, this does not bode well for abalone populations, which are of significant economic value and are already in trouble owing to global warming, increasing risk of disease [32]. More data are required to determine whether high sensitivity to climate change stressors is specific to Haliotis or also a feature of other gastropod larvae.…”

“…These species co-occur in southeast Australia, a climate change hotspot, where the ocean is warming several times faster than the global average [30]. They represent ecologically and commercially important marine invertebrates because they function as grazers that structure habitats and are targeted by fisheries [31,32]. We investigated the interactive effects of near-future (ca 2100 [4]) ocean warming, acidification/ hypercapnia, and decreased aragonite and calcite saturation states on development in these two species.…”

Les systèmes aquacoles face au changement climatique

“…Ces changements de température ont, par exemple, provoqué l'accroissement de la virulence de pathogènes tels que Vibrio harveyi, occasionnant des mortalités élevées sur les ormeaux (Travers et al, 2009). Dans le cas du tilapia Oreochromis niloticus, une plus grande (Kayansamruaj et al, 2014 ;Marcusso et al, 2015).…”

Seasonal antibacterial activity of two red seaweeds,PalmariapalmataandGrateloupia turuturu, on European abalone pathogenVibrio harveyi

“…• C (high optimal growth temperature of V. harveyi -Travers et al 2009). Bacterial growth was monitored by measuring optical density (OD) at 490 nm every 30 min for 24 h. After incubation, the intensity of growth in the presence of the tested compounds and controls was compared.…”