A deep nursery for juveniles of the zebra angelfish Genicanthus caudovittatus

Abstract

Juveniles of many coral reef fish species are thought to either follow the same bathymetric distribution patterns as the adults, or to occupy shallower waters. However, our knowledge base suffers a dearth of data from the deep reefs (>40 m). In a recent survey of the deep reefs of the northern Gulf of Aqaba (<65 m), we examined the bathymetric distribution of 26 diurnal zooplanktivorous species. In sharp contrast to the general trend known from the literature and from this research, the abundance of juvenile zebra angelfish, Genicanthus caudovittatus, peaked at deeper waters (60-65 m) compared with the adults (30 m). This suggests that the deeper reefs may serve as nursery grounds for the zebra angelfish. Peak juvenile abundance coincided with relatively low predator abundances. This raises the question, which factors constrain the bathymetric distribution of the remaining species. Our findings stress the potential importance of deep coral reef research for understanding the ecological patterns and processes that govern reef community structure.

Fitness consequences of habitat variability, trophic position, and energy allocation across the depth distribution of a coral-reef fish

“…While habitat quality clearly influences demersal reef-fish populations (Almany 2004;Boström-Einarsson et al 2014), few studies have assessed habitat suitability linked to distributional limitations across the full depth range of a species (Srinivasan 2003;Brokovich et al 2007;Hoey et al 2007). Mesophotic coral ecosystems (*30-150 m) that extend to the depth boundaries of photosynthetic hermatypic coral reefs may be important refuges for coral-reef-fish populations (Lindfield et al 2016) and sources of larval supply for degraded shallow reefs (Lesser et al 2009).…”

Ecological Drivers of Invasive Lionfish (Pterois volitans and Pterois miles) Distribution Across Mesophotic Reefs in Bermuda

“…However, the inability to remove individuals from deep reefs will enable continued recruitment to fished locations, as mesophotic lionfish are highly fecund (Eddy, 2016;Andradi-Brown et al, 2017b), potentially offsetting the efficacy of local shallow water culling (Johnston and Purkis, 2015;Andradi-Brown et al, 2017a). Given the documented importance of MCEs as critical nursery habitats for several reef fish species (Lobel, 1981;Randall and Chen, 1985;Brokovich et al, 2007;Garcia-Sais, 2010;Sazima et al, 2010;Lindfield et al, 2016), it is important that lionfish populations at mesophotic depths are incorporated into management strategies. The results presented here suggest that lionfish distribution on mesophotic reefs is influenced in part by physical parameters of the environment, such as temperature, as well as ecological parameters, such as the availability of potential prey.…”

Trophic designation and live coral cover predict changes in reef-fish community structure along a shallow to mesophotic gradient in Hawaii

“…The few ecological studies conducted on mesophotic reefs (30-150 m) support the premise of deep reefs providing substantial habitat for fishes (Brokovich et al 2007(Brokovich et al , 2008Lesser et al 2009;Bejarano et al 2014). Studies of mesophotic communities in the Caribbean and Red Sea reveal that coral cover is consistent to at least 50-60 m depth (Goreau and Goreau 1973;Fricke and Schumacher 1983;Liddell and Ohlhorst 1988;Liddell et al 1997;Bak et al 2005;Brokovich et al 2008 revealed a unique and extensive mesophotic coral bed, providing structure for immense mesophotic fish communities (Kahng et al 2010).…”

“…Few studies have focused on the ecology of fishes of mesophotic coral ecosystems (MCE; [30 m). These studies predominantly describe species composition and species-habitat relationships using observational techniques, and relate changes in community structure largely to depth and changes in coral abundance or morphology (Colin 1974;Thresher and Colin 1986;Pyle 2000;Feitoza et al 2005;Brokovich et al 2007Brokovich et al , 2008Brokovich et al , 2010aGarcia-Sais 2010;Bryan et al 2013;Bejarano et al 2014;Schultz et al 2014;Lindfield et al 2016). To date, five studies have investigated reef fishes at mesophotic depths in Hawaii: three in the remote northwestern Hawaiian Islands (Parrish and Boland 2004;Kane et al 2014;Fukunaga et al 2016); one from Maui in the main Hawaiian Islands (Boland and Parrish 2005); and one encompassing both the northwestern Hawaiian Islands and Au'au Channel in Maui (Pyle et al 2016).…”