Settlement patterns of Caribbean scleractinian corals on artificial substrata along a eutrophication gradient, Barbados, West Indies

Abstract

Artificial substrate settlement plates (terracotta tiles) were set out on 3 fringing reefs for a period of 12 mo to study settlement patterns of juvenile scleractinian corals along a eutrophication gradient on the west coast of Barbados, W.I. A total of 716 coral planulae settled on 120 experimental plates after 12 mo of exposure. Statistically higher ( p 0.05) average number of juvenile corals per plate (R= 9.2 f 3.3; N = 40) was recorded on a less eutrophic reef compared to 2 more eutrophic reefs (X = 6.9 f 3.1; N = 40 and X = 1 9 i 1.3; N = 40) Differences in juvenile coral settlement between reef zones, within each reef, were dependent on the reef's position along the eutrophication gradient. Statistically higher number of coral planulae (;if = 7.2 + 4.5; N = 60) successfully settled on vertical plates compared to horizontal plates (X = 4.8 + 3.3; N = 60). Coral planulae did not settle on upper surfaces of horizontal plates. In terms of relative abundance, the most common coral species in the juvenile population on the experimental plates were Porites astreoides Lamarck which accounted for 42% of the settled planulae, followed by Agaricia spp. (23%); and F! porites (Pallas) (19%). Juveniles of Montastrea annularis (Ellis & Solander), Siderastrea spp, and Diplona spp , while present at 2 northern reefs, were absent from the most eutrophic reef.

Unsustainable Land Use, Sediment-Laden Runoff, and Chronic Raw Sewage Offset the Benefits of Coral Reef Ecosystems in a No-Take Marine Protected Area

“…In contrast, sites under strong water circulation, which prevents sediment deposition, were largely dominated by higher coral species richness, H'n, J'n, CCA, and by a higher abundance of juvenile corals and sponges. These patterns reflected variation associated to gradient impacts and were consistent with previous observations in the Caribbean (Tomascik & Sander, 1987a;Tomascik, 1991). , 2014).…”

“…Eutrophication may also foster phytoplankton blooms (Bell, 1992;McComb, 1995;Arhonditsis, Karydis, & Tsirtsis, 2003), harmful algal blooms (Anderson, Glibert, & Burkholder, 2002), rapid macroalgal growth (Naim, 1993), a long-term decline in fisheries productivity (Hodgkiss & Yim, 1995), and a net decline in seagrass (Duarte, 1995;Tomasko, Dawes & Hall, 1996) and coral reef communities (Lapointe & Clark, 1992;Cloern, 2001;Dí az-Ortega & Herná ndez-Delgado, 2014;Duprey, Yasuhara, & Baker, 2016). Corals are particularly susceptible to eutrophication as a result of declining growth rates (Tomascik & Sander, 1985;Tomascik, 1990), reproductive output (Tomascik & Sander, 1987b), larval settlement rates (Tomascik, 1991), increased incidence of diseases (Kaczmarsky, Draud, & Williams, 2005), altered Environmental Management and Sustainable Development ISSN 2164-7682 2017 microbiology (Kline, Kuntz, Breitbart, Knowlton et al, 2006), and increased susceptibility to bleaching (Vega-Thurber, Burkepile, Fuchs, Shantz et al, 2013;Wiedenmann et al, 2013), and mortality (Pastorok & Byliard, 1985), often impacting benthic community structure (Tomascik & Sander, 1987a). These impacts are often confounded with sedimentation effects (Rogers, 1990;Meesters, Bak, Westmacott, Ridgley et al, 1998;Risk, 2014), and can be readily magnified by climate change-related factors (Ateweberhan, Feary, Keshavmurthy, Chen et al, 2013).…”

Coral recruitment and potential recovery of eutrophied and blast fishing impacted reefs in Spermonde Archipelago, Indonesia

“…The comparatively high settlement on the upper tiles near-shore in contrast to the mid-shelf and off-shore reefs is most likely a response to critically low light levels in these turbid coastal waters (Sammarco, 1991;Maida et al, 1994). Pocilloporids are considered opportunistic corals (Birkeland, 1977;Tomascik, 1991) successfully reproducing in nutrient-and sediment laden waters adverse to other corals (Gilmour, 1999;Harrison and Ward, 2001). They are also able to settle and metamorphose on filamentous algae covered substrates as supported by the results of this study.…”

“…Anthropogenic impacts may have significant negative effects on natural recruitment patterns in corals (Tomascik, 1991;Abelson et al, 2005). Eutrophication, pollution and sedimentation were found to hamper gamete production, alter the timing of spawning and decrease the fertilization success (Gilmour, 1999;Loya et al, 2004).…”

“…They were found to slow the development and metamorphosis of the larvae and decrease the survival of the coral recruits (Gilmour, 1999;Hughes and Connell, 1999;Abelson et al, 2005). Eutrophication is also known to foster the growth of potential space competitors of coral recruits (Tomascik, 1991;Dunstan and Johnson, 1998;Abelson et al, 2005), toxic cyanobacteria or macroalgae inhibiting coral larvae settlement (Kuffner and Paul, 2004). Sedimentation is known to hamper larvae settlement and to smother coral recruits (Hodgson, 1990).…”