The Role of Maternal Nutrition on Oocyte Size and Quality, with Respect to Early Larval Development in The Coral-Eating Starfish, Acanthaster planci

Abstract

Variation in local environmental conditions can have pronounced effects on the population structure and dynamics of marine organisms. Previous studies on crown-of-thorns starfish, Acanthaster planci, have primarily focused on effects of water quality and nutrient availability on larval growth and survival, while the role of maternal nutrition on reproduction and larval development has been overlooked. To examine the effects of maternal nutrition on oocyte size and early larval development in A. planci, we pre-conditioned females for 60 days on alternative diets of preferred coral prey (Acropora abrotanoides) versus non-preferred coral prey (Porites rus) and compared resulting gametes and progeny to those produced by females that were starved over the same period. Females fed ad libitum with Acropora increased in weight, produced heavier gonads and produced larger oocytes compared to Porites-fed and starved females. Fed starfish (regardless of whether it was Acropora or Porites) produced bigger larvae with larger stomachs and had a higher frequency of normal larvae that reached the late bipinnaria / early brachiolaria stage compared to starved starfish. Females on Acropora diet also produced a higher proportion of larvae that progressed to more advanced stages faster compared to Porites-fed starfish, which progressed faster than starved starfish. These results suggest that maternal provisioning can have important consequences for the quality and quantity of progeny. Because food quality (coral community structure) and quantity (coral abundance) varies widely among reef locations and habitats, local variation in maternal nutrition of A. planci is likely to moderate reproductive success and may explain temporal and spatial fluctuations in abundance of this species.

30 Years of Research on Crown-of-thorns Starfish (1986-2016): Scientific Advances and Emerging Opportunities

“…Moreover, CoTS can persist without food for many months (Moran 1986), and so it seems unlikely that it is a lack of coral per se, that causes elevated mortality or initiates mass exodus from reefs. It is possible, however, that limited access to preferred coral prey (e.g., Acropora) leads to compromised health and condition of CoTS (Lucas 1984;Caballes et al 2016), despite relatively high overall coral cover on reefs subject to moderate CoTS outbreaks.…”

“…Caballes et al (2016) demonstrated that differences in the nutritional condition of female A. cf. solaris, based on contrasting diets (e.g., Acropora versus Porites), have a major bearing on the growth and performance of their progeny.…”

“…3) is extremely challenging. In culture, concentrations of CoTS larvae steadily decline with time (Wolfe et al 2015a;Caballes et al 2016Caballes et al , 2017aPratchett et al 2017b), indicative of significant rates intrinsic larval mortality (Rumrill 1990), which depend on food availability (section 2.1) and food quality (section 2.3). Mortality rates recorded for larvae in laboratory cultures ranged from 19% to 45% after 10 days (Wolfe et al 2015a).…”

“…The extent to which development and survival rates of CoTS larvae are constrained by exogenous food availability is equivocal, and somewhat dependent on several other factors (e.g., maternal provisioning of larvae, and vulnerability to predation). Caballes et al (2016) demonstrated that differences in the nutritional condition of female A. cf. solaris, based on contrasting diets (e.g., Acropora versus Porites), have a major bearing on the growth and performance of their progeny.…”

“…Moreover, CoTS can persist without food for many months (Moran 1986), and so it seems unlikely that it is a lack of coral per se, that causes elevated mortality or initiates mass exodus from reefs. It is possible, however, that limited access to preferred coral prey (e.g., Acropora) leads to compromised health and condition of CoTS (Lucas 1984;Caballes et al 2016), despite relatively high overall coral cover on reefs subject to moderate CoTS outbreaks.The extent to which CoTS actually move between reefs is largely unresolved (section 2.18). Even though starvation is a potential trigger for movement by CoTS (Sigl and Laforsch 2016) and there will be strong motivation to move away from reefs following extensive depletion of coral prey, by the time this happens, the starfish are likely to have already depleted much of their energy reserves thereby constraining the capacity for long-distance migration.…”