English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Censuses were taken at 8 coral reefs in southwest Puerto Rico to identlfy assemblages of flshes and to determine whether water motion, depth, and substrate were correlated with fish distributlon and abundance. Each reef was sampled by recording species and abundance of fishes and substrate sizes within quadrats placed at different depths (from reef crest to an average of 6 m deep) along transects placed on forereefs and backreefs. Water motion was examined by measuring the amount of dissolution of plaster-of-Paris blocks wh~ch gave a relative index of the degree of water movement wlthin and among reefs. Data collected on 14 fish specles and measurements of water motion, degree of reef slope, and 4 sizes of substrate over 32 transects were analyzed to identify species groups and examine ecological correlates. The analyses indicated 3 species assemblages which d~ffered in distnbution and abundance within reefs (backreef, shallow forereef, and deep forereef) and among reefs (nearshore, intermediate, and offshore reefs). Similarly, water movement, depth, reef slope and substrate size occurred as gradients that differed significantly within and among reefs. Fishes in Assemblage 1 included primarily Ophioblennius atlanticus. Thalassoma bifasciatum, Stegastes dorsopunicans, and Microspathodon chrysurus. These species were most common on the shallow forereef, particularly at offshore reefs (those farthest from land); these sites were characterized by a high degree of water motion, gentle forereef slope, and boulder-sized substrate. Assemblage 2 species included Stegastesplanifrons, Hypoplectrus chlorurus, and Holocentrus rufus. These fishes were most abundant on the deep forereef, especially at nearshore reefs (sites closest to land), which were typified by relatively low water movement, steep slope, and smaller substrate sizes. Fishes in Assemblage 3 (Stegastes leucostictus and Malacoctenus macropus) were most numerous in the backreef where water motion, slope inclination, and substrate sizes were minimal compared with the forereef. While biological variables are undoubtedly important in determining species distributions, the different assemblages were found to be correlated with variations in water motion, depth, and substrate type. These 3 physical variables occurred as interrelated gradients, but the analyses suggested that water movement energy was the environmental factor most strongly associated with species distributions.

Correspondence between assemblages of coral reef fishes and gradients of water motion, depth, and substrate size off Puerto Rico