Augmenting the Post-Transplantation Growth and Survivorship of Juvenile Scleractinian Corals via Nutritional Enhancement

Abstract

Size-dependant mortality influences the recolonization success of juvenile corals transplanted for reef restoration and assisting juvenile corals attain a refuge size would thus improve post-transplantation survivorship. To explore colony size augmentation strategies, recruits of the scleractinian coral Pocillopora damicornis were fed with live Artemia salina nauplii twice a week for 24 weeks in an ex situ coral nursery. Fed recruits grew significantly faster than unfed ones, with corals in the 3600, 1800, 600 and 0 (control) nauplii/L groups exhibiting volumetric growth rates of 10.65±1.46, 4.69±0.9, 3.64±0.55 and 1.18±0.37 mm3/week, respectively. Corals supplied with the highest density of nauplii increased their ecological volume by more than 74 times their initial size, achieving a mean final volume of 248.38±33.44 mm3. The benefits of feeding were apparent even after transplantation to the reef. The corals in the 3600, 1800, 600 and 0 nauplii/L groups grew to final sizes of 4875±260 mm3, 2036±627 mm3, 1066±70 mm3 and 512±116 mm3, respectively. The fed corals had significantly higher survival rates than the unfed ones after transplantation (63%, 59%, 56% and 38% for the 3600, 1800, 600 and 0 nauplii/L treatments respectively). Additionally, cost-effectiveness analysis revealed that the costs per unit volumetric growth were drastically reduced with increasing feed densities. Corals fed with the highest density of nauplii were the most cost-effective (US$0.02/mm3), and were more than 12 times cheaper than the controls. This study demonstrated that nutrition enhancement can augment coral growth and post-transplantation survival, and is a biologically and economically viable option that can be used to supplement existing coral mariculture procedures and enhance reef restoration outcomes.

Coral Reef Restoration in Singapore — Past, Present and Future

“…Cost-benefit analyses also represent a useful tool for monetising strategies so that reef restoration can be carried out more effectively at lower cost (Edwards et al, 2010b). Toh et al (2014) showed that while labour and equipment contributed significantly to the cost of producing sexually propagated corals for transplantation, greater economies of scale could be achieved by introducing feeds to augment coral growth during the nursery phase. Additionally, factors such as the evolutionary distinctiveness or vulnerability of a species to global extinction can be considered when prioritising corals for restoration (Curnick et al, 2015;Huang and Roy, 2015), to supplement broad-based proxies such as site-specific species rarity.…”

Nutrition in ornamental aquaculture: the raise of anthropocentrism in aquaculture?

“…nauplii show optimal growth and survival in home aquaria (Van Os et al 2012). Invertebrate feeding, such as corals, is highly improved if live food can be used (Toh et al 2014). It seems that this sector is dominated by aquafeed companies information more than by scientific information (Forsman et al 2012).…”

“…; Monticini ; Toh et al . ). Therefore, several studies are focussed on modern aquaculture methods for improving ornamental farming (Pomeroy et al .…”

“…Considering that at least 95% of exploited fish and invertebrates are directly collected from coral reefs in several countries and regions including Brazil, Maldives, Vietnam, Sri Lanka, Hawaii, Indonesia, Philippines and the Caribbean (Avella et al 2007;Murray et al 2012;Murray & Watson 2014), research on ornamental aquaculture aims to reverse or minimize the impacts imposed by capture practises in coral reef and beyond (Steinke et al 2009;Monticini 2010;Toh et al 2014). Therefore, several studies are focussed on modern aquaculture methods for improving ornamental farming (Pomeroy et al 2006;Olivotto et al 2011;Barton et al 2015;Moorhead & Zeng 2015).…”

Quantifying growth in maricultured corals using photogrammetry

“…While there has been significant progress in rearing techniques, such as introducing nutritious feeds and increasing bicarbonate ions to enhance coral growth rates (Forsman, Page, Toonen, & Vaughan, 2015;Lirman et al, 2014;Marubini & Thake, 1999;Toh, Ng, Peh, Toh, & Chou, 2014), it is also essential that the enhanced productivity is documented by precise measurements. In coral mariculture, various methods exist to determine growth rates.…”