: Mortality rates of marine invertebrate taxa during the first 4 weeks following settlement. Estimates were derived via the weekly standardised survival calculated by Hunt and Scheibling (1997) and from estimates of cumulative morality presented in Gosselin and Qian (1997). other data were obtained from Stoner (1990), Hurlbut (1991) and Petersen and Svane (1995). Time Taxon Cumulative mortality Week 1 Barnacles 0 78% – Bryozoa 1 6% – Bivalves 15 20% – Gastropods 23% Colonial ascidians 0 90% – Solitary ascidians 13 43% – Week 2 Barnacles 0 75% – Bryozoa 2 12% – Bivalves 28 36% – Gastropods 41% Colonial ascidians 0 -100% Solitary ascidians 24 68% – Week 3 Barnacles 0 88% – Bryozoa 3 17% – Bivalves 39 49% – Gastropods 54% Colonial ascidians 0 100% – Solitary ascidians 34 81% – Week 4 Barnacles 0 94% – Bryozoa 4 22% – Bivalves 48 59% – Gastropods 24 99% – Colonial ascidians 22 99% – Solitary ascidians 43 89% – Mortality induced by vessel voyages During vessel voyages, biofouling organisms are exposed to hydrodynamic drag that can have a significant effect on survival via dislodgement or inhibition of feeding. Typically, vessels (> 15 knots) in regular use have relatively low levels of biofouling that are mostly confined to niche areas protected from voyage-induced drag. Slow-moving (< 5 knots) vessels, such as barges and many sailing yachts, are more likely to support biofouling assemblages that are more widespread across the submerged hull area (Foster and Willan 1979; James and Hayden 2000; Coutts and Taylor 2004; Davidson et al. 2008; Inglis et al. 2010). Coutts et al. (2009) tested the effect of vessel speed on biofouling assemblages up to 7 days following voyages of 20 minutes duration. They found that: (1) vessel speeds of 5 and 10 knots had little effect on biofouling species richness, but species richness decreased by 50% following voyages of 18 knots, (2) percentage biofouling cover decreased with
: Mortality rates of marine invertebrate taxa during the first 4 weeks following settlement. Estimates were derived via the weekly standardised survival calculated by Hunt and Scheibling (1997) and from estimates of cumulative morality presented in Gosselin and Qian (1997). other data were obtained from Stoner (1990), Hurlbut (1991) and Petersen and Svane (1995). Time Taxon Cumulative mortality Week 1 Barnacles 0 – 78% Bryozoa 1 – 6% Bivalves 15 – 20% Gastropods 23% Colonial ascidians 0 – 90% Solitary ascidians 13 – 43% Week 2 Barnacles 0 – 75% Bryozoa 2 – 12% Bivalves 28 – 36% Gastropods 41% Colonial ascidians 0 -100% Solitary ascidians 24 – 68% Week 3 Barnacles 0 – 88% Bryozoa 3 – 17% Bivalves 39 – 49% Gastropods 54% Colonial ascidians 0 – 100% Solitary ascidians 34 – 81% Week 4 Barnacles 0 – 94% Bryozoa 4 – 22% Bivalves 48 – 59% Gastropods 24 – 99% Colonial ascidians 22 – 99% Solitary ascidians 43 – 89% Mortality induced by vessel voyages During vessel voyages, biofouling organisms are exposed to hydrodynamic drag that can have a significant effect on survival via dislodgement or inhibition of feeding. Typically, vessels (> 15 knots) in regular use have relatively low levels of biofouling that are mostly confined to niche areas protected from voyage-induced drag. Slow-moving (< 5 knots) vessels, such as barges and many sailing yachts, are more likely to support biofouling assemblages that are more widespread across the submerged hull area (Foster and Willan 1979; James and Hayden 2000; Coutts and Taylor 2004; Davidson et al. 2008; Inglis et al. 2010). Coutts et al. (2009) tested the effect of vessel speed on biofouling assemblages up to 7 days following voyages of 20 minutes duration. They found that: (1) vessel speeds of 5 and 10 knots had little effect on biofouling species richness, but species richness decreased by 50% following voyages of 18 knots, (2) percentage biofouling cover decreased with