Isolation promotes abundance and species richness of fishes recruiting to coral reef patches
- PDF / 1,061,105 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 54 Downloads / 171 Views
ORIGINAL PAPER
Isolation promotes abundance and species richness of fishes recruiting to coral reef patches G. P. Jones1,2 · G. Barone1,3 · K. Sambrook1,2 · M. C. Bonin1,2,4 Received: 26 March 2020 / Accepted: 25 September 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Habitat area and fragmentation are recognised as important factors that influence population size, community structure and extinction risk. Abundance and species richness universally increase with habitat area. However, the effects of different aspects of habitat fragmentation, including variation in patch size, number and isolation are often not distinguished from each other or the overall effects of habitat amount. Here we experimentally tested predictions concerning the effects of isolation on abundance, species richness and community structure of coral reef fishes colonising patch reefs by constructing clusters of patches of the same number and size, but manipulating reef spacing. Hexagonal clusters of 7 experimental patch reefs (6 edge and 1 central) with 3 levels of isolation (1 m, 5 m, and 15 m spacing) were established at Kavieng, Papua New Guinea and colonisation was recorded after 6 weeks in 2014. We also deployed video cameras to test whether isolation affected the activity of transient predatory fishes. As predicted, isolation had a positive effect on both mean abundance and species richness at both the cluster and patch scale. The cumulative abundance and species richness exhibited linear increases in relation to habitat area within clusters (from 1 to 7 patch reefs), but the slope increased with the degree of isolation. There was some evidence that transient predators remained longer and were more successful when patches were close together, which may explain the lower abundance and richness of juvenile fish assemblages on more aggregated patch reefs. This study demonstrates that while habitat amount is fundamentally important, isolation has significant effects that will need to be distinguished from other aspects of fragmentation when examining the processes structuring reef fish communities.
Introduction
Responsible Editor: K. D. Clements. Reviewed by undisclosed experts. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00227-020-03772-0) contains supplementary material, which is available to authorized users. * G. P. Jones [email protected] 1
College of Science and Engineering, James Cook University, Townsville, Queensland 4811, Australia
2
ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
3
National Research Council, Institute for Biological Resources and Marine Biotechnologies, Largo Fiera della Pesca, 60125 Ancona, Italy
4
Great Barrier Reef Marine Park Authority, Townsville, QLD 4810, Australia
Habitat loss is considered one of the major causes of the global decline in biodiversity, with the area of many natural habitats reduced to a small fraction of their historic
Data Loading...
