Spatio-Temporal Patterns in the Coral Reef Communities of the Spermonde Archipelago, 2012–2014, II: Fish Assemblages Display Structured Variation Related to Benthic Condition

Abstract

The Spermonde Archipelago is a complex of ∼70 mostly populated islands off Southwest Sulawesi, Indonesia, in the center of the Coral Triangle. The reefs in this area are exposed to a high level of anthropogenic disturbances. Previous studies have shown that variation in the benthos is strongly linked to water quality and distance from the mainland. However, little is known about the fish assemblages of the region and if their community structure also follows a relationship with benthic structure and distance from shore. In this study, we used eight islands of the archipelago, varying in distance from 1 to 55 km relative to the mainland, and 3 years of surveys, to describe benthic and fish assemblages and to examine the spatial and temporal influence of benthic composition on the structure of the fish assemblages. Cluster analysis indicated that distinct groups of fish were associated with distance, while few species were present across the entire range of sites. Relating fish communities to benthic composition using a multivariate generalized linear model confirmed that fish groups relate to structural complexity (rugosity) or differing benthic groups; either algae, reef builders (coral and crustose coralline algae) or invertebrates and rubble. From these relationships we can identify sets of fish species that may be lost given continued degradation of the Spermonde reefs. Lastly, the incorporation of water quality, benthic and fish indices indicates that local coral reefs responded positively after an acute disturbance in 2013 with increases in reef builders and fish diversity over relatively short (1 year) time frames. This study contributes an important, missing component (fish community structure) to the growing literature on the Spermonde Archipelago, a system that features environmental pressures common in the greater Southeast Asian region.

High taxonomic resolution surveys and trait-based analyses reveal multiple benthic regimes in North Sulawesi (Indonesia)

“…Proliferation of colonial ascidians has also been reported on several reefs after increases in nutrient availability and overfishing 58 , 61 . Increases in these organisms can have severe effects on reef health and functioning by altering reef replenishment, geomorphology and trophic structure 58 , 62 , 63 . Here, we observed that the two communities dominated by potentially proliferating organisms displayed simultaneously the lowest fish and benthic functional diversities, including the lowest diversity and cover of reef-building functional entities, such as branching corals.…”

Contrasting Responses in the Niches of Two Coral Reef Herbivores Along a Gradient of Habitat Disturbance in the Spermonde Archipelago, Indonesia

“…Benthic communities were quantified in parallel with Teichberg et al (2018) and Plass-Johnson et al (2018). At each island there were 50 photographic quadrats per 50 m transect.…”

Cross shelf gradients of scleractinian corals in the Spermonde Islands, South Sulawesi, Indonesia

“…There have been studies on various aspects of reef health and biodiversity across this gradient in the Spermonde Islands over the past decades (Moll 1983;Best et al 1989;CRITC 2012;Hoeksema 2012b), as well as more recent studies on coral reefs and associated biodiversity (Plass-Johnson et al 2018a;Plass-Johnson et al 2018b;Teichberg et al 2018). However, there is a need for updated and/or complementary data on certain aspects of coral community biodiversity, ecology and health.…”