1
|
Goiran C, Shine T, Shine R. The banded colour patterns of sea snakes discourage attack by predatory fishes, enabling Batesian mimicry by harmless species. Proc Biol Sci 2022; 289:20221759. [PMID: 36382516 PMCID: PMC9667369 DOI: 10.1098/rspb.2022.1759] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 10/30/2022] [Indexed: 02/26/2024] Open
Abstract
The evolution of bright 'warning' colours in nontoxic animals often is attributed to mimicry of toxic species, but empirical tests of that hypothesis must overcome the logistical challenge of quantifying differential rates of predation in nature. Populations of a harmless sea snake species (Emydocephalus annulatus) in New Caledonia exhibit colour polymorphism, with around 20% of individuals banded rather than melanic. Stability in that proportion over 20 years has been attributed to Batesian mimicry of deadly snake species by banded morphs of the harmless taxon. This hypothesis requires that banded colours reduce a snake's vulnerability to predation. We tested that idea by pulling flexible snake-shaped models through the water and recording responses by predatory fish. Black and banded lures attracted similar numbers of following fish, but attacks were directed almost exclusively to black lures. Our methods overcome several ambiguities associated with experimental studies on mimicry in terrestrial snakes and support the hypothesis that banded colour patterns reduce a non-venomous marine snake's vulnerability to predation.
Collapse
Affiliation(s)
- Claire Goiran
- LabEx Corail & ISEA, Université de la Nouvelle-Calédonie, BP R4, 98851 Nouméa cedex, New Caledonia
| | - Terri Shine
- School of Natural Sciences, Macquarie University, New South Wales 2109, Australia
| | - Richard Shine
- School of Natural Sciences, Macquarie University, New South Wales 2109, Australia
| |
Collapse
|
2
|
Mihalitsis M, Morais RA, Bellwood DR. Small predators dominate fish predation in coral reef communities. PLoS Biol 2022; 20:e3001898. [PMID: 36445867 PMCID: PMC9707750 DOI: 10.1371/journal.pbio.3001898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 10/31/2022] [Indexed: 12/03/2022] Open
Abstract
Ecosystem processes are challenging to quantify at a community level, particularly within complex ecosystems (e.g., rainforests, coral reefs). Predation is one of the most important types of species interactions, determining several ecosystem processes. However, while it is widely recognised, it is rarely quantified, especially in aquatic systems. To address these issues, we model predation on fish by fish, in a hyperdiverse coral reef community. We show that body sizes previously examined in fish-fish predation studies (based on a metanalysis), only represent about 5% of likely predation events. The average fish predator on coral reefs is just 3.65 cm; the average fish prey just 1.5 cm. These results call for a shift in the way we view fish predation and its ability to shape the species or functional composition of coral reef fish communities. Considered from a functional group approach, we found general agreement in the distribution of simulated and observed predation events, among both predator and prey functional groups. Predation on coral reefs is a process driven by small fish, most of which are neither seen nor quantified.
Collapse
Affiliation(s)
- Michalis Mihalitsis
- Research Hub for Coral Reef Ecosystem Functions, James Cook University, Townsville, Queensland, Australia
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
- Department of Evolution and Ecology, University of California, Davis, California, United States of America
- * E-mail:
| | - Renato A. Morais
- Research Hub for Coral Reef Ecosystem Functions, James Cook University, Townsville, Queensland, Australia
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
| | - David R. Bellwood
- Research Hub for Coral Reef Ecosystem Functions, James Cook University, Townsville, Queensland, Australia
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
| |
Collapse
|