Revisiting the winners and the losers a decade after coral bleaching

Abstract

Over the past 3 decades, thermal stress events have damaged corals globally. Few studies, however, have tracked the recovery process or assessed whether winners in the short term are also winners in the long term. In the present study, we repeatedly sampled a coral assemblage over a 14 yr period, from 1997 to 2010, through 2 thermal stress events (in 1998 and 2001). Our goal was to examine the consistency of short-term winner and loser outcomes over the recovery period. Although species richness had recovered after 10 yr, the reef composition had changed, and few pocilloporids were to be found. The short-term winners were the thermally tolerant encrusting and massive coral morphologies (Porites and faviids) and Acropora colonies < 5 cm in diameter. Long-term winners were revealed as (1) thermally tolerant, locally persistent colonies, (2) remnant survivors that rapidly regrew, and (3) regionally persistent colonies that recruited. KEY WORDS: Coral bleaching · Climate adaptation · Temperature · Reefs · RecoveryResale or republication not permitted without written consent of the publisher Mar Ecol Prog Ser 434: 67-76, 2011 enced anomalous temperatures only every 50 to 60 yr (Thompson & van Woesik 2009). For example, the southern islands of Japan, the Great Barrier Reef and Micronesia all historically show low-frequency return periods (~50 yr), whereas the Galapagos Islands and Kiribati historically show high-frequency return periods (~5 yr) (Thompson & van Woesik 2009). Not only are contemporary worldwide patterns in thermal anomalies similar to those in the past, but the localities that have shown high-frequency return periods in the past few centuries have also recently experienced the most severe thermal stress (Thompson & van Woesik 2009). If these patterns persist into the near future, then some localities will receive both more intensive and more frequent thermal stress than other localities.Short-term studies suggest that some coral species are destined to become the 'winners', whereas others are destined to become the 'losers' (Loya et al. 2001). However, simply tolerating local thermal stress is not the only viable life-history strategy to persist through time. Ephemeral assemblages that are usually susceptible to local stress also survive regionally by being highly fecund and growing quickly (MacArthur & Wilson 1967, Loya 1976, Gates & Edmunds 1999. Regional persistence also depends on (1) the local survival of small fragments, which have an inherent capacity for regrowth, (2) whether corals on neighboring reefs survived through the thermal stress, (3) whether those neighboring corals have the capacity to supply recruits, (4) the survival of recruits from neighboring reefs, and (5) the return frequency and intensity of the thermal stresses.Few studies have examined the longterm recovery of coral assemblages following thermal stress. Here, we ask whether a winning species in the short term is also a winner in the long term. Previously we reported on the shortterm effects of a severe thermal s...

Endosymbiotic flexibility associates with environmental sensitivity in scleractinian corals

“…In contrast, coral species with high symbiotic specificity (i.e. high fidelity with respect to Symbiodinium) such as massive environmentally resilient poritids are ecological 'winners' [62,63,69,70].…”

“…For example, massive Porites colonies associate with Symbiodinium C15 from depths of 1-17 m across the GBR, and in corals collected in Japan [77], Johnston Atoll [11] and American Samoa [32]. Massive Porites is exemplified by a greater stability and persistence over time and under stressful conditions [32,57,61,76], traits attributed to slow growth [57], thick tissues/high tissue biomass [61,63] and thermally tolerant Symbiodinium C15 [78,79]. Characteristics of specifist corals such as Porites include symbiosis with endosymbionts such as Symbiodinium C15, which is commonly transmitted vertically across generations in the host [56], a mechanism that promotes coevolution and integration with the host, and is one of the most highly derived members of the most derived clade C [9,80].…”

Environmental Drivers of Variation in Bleaching Severity of Acropora Species during an Extreme Thermal Anomaly

“…In general, the literature documents relatively high bleaching severity for branching corals from the genera Stylophora, Acropora, and Pocillopora, and lower bleaching severity for mound-shaped Porites and Diploastrea (e.g., Marshall and Baird, 2000;Loya et al, 2001;van Woesik et al, 2011;Swain et al, 2016). However, bleaching severity is spatially patchy (e.g., Wooldridge and Done, 2004;Penin et al, 2007).…”

Evaluating the causal basis of ecological success within the scleractinia: an integral projection model approach

“…and Acropora spp. that represent the concept of ecological winners and losers, respectively (Loya et al 2001;van Woesik et al 2011), and rejected the null hypothesis of no difference between taxa for six traits (biomass, tissue thickness, linear extension, photosynthesis, chlorophyll-a, and calcification; t > 2.222, df ≥ 9, P ≤ 0.034); six additional traits did not differ between these genera (t ≤ 0.917, df ≤ 44, P ≥ 0.128). The weak phenotypic discrimination among coral taxa that have been extensively studied for the select traits was revealed when they were clustered based on similarities generated from all 12 traits (Fig.…”