Musical chairs mortality functions: density-dependent deaths caused by competition for unguarded refuges

• Published in: Oecologia Vol. 160; no. 2; pp. 257 - 265
• Main Authors: Samhouri, Jameal F, Vance, Richard R, Forrester, Graham E, Steele, Mark A
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.05.2009; Springer; Springer-Verlag; Springer Nature B.V
• Subjects: Agnatha. Pisces; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Biomedical and Life Sciences; Competitive Behavior - physiology; Coral reef fish; Coral reefs; Coryphopterus glaucofraenum; Density dependence; Ecological competition; Ecology; Fundamental and applied biological sciences. Psychology; General aspects; Hydrology/Water Resources; Life Sciences; Marine ecology; Mathematical functions; Models, Theoretical; Mortality; Mortality functions; Musical chairs; Perciformes - physiology; Plant Sciences; Population Density; Population ecology; Population Ecology - Original Paper; Predation; Predators; Prey; Ratios; Refuges; Statistics; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; ASW, Caribbean Sea; Density dependence; Coral reef fish; Mortality functions; Refuges; Competition; Mortality; Coral reef; Refuge; Marine environment; Vertebrata; Gobiidae; Pisces; Reef animal; Coryphopterus glaucofraenum
• ISSN: 0029-8549; 1432-1939
• DOI: 10.1007/s00442-009-1307-z

Structural refuges within which prey can escape from predators can be an important limiting resource for the prey. In a manner that resembles the childhood game of musical chairs, many prey species rapidly retreat to shared, unguarded refuges whenever a predator threatens, and only when refuges are relatively abundant do all prey individuals actually escape. The key feature of this process is that the per capita prey mortality rate depends on the ratio of prey individuals to refuges. We introduce a new class of mortality functions with this feature and then demonstrate statistically that they describe field mortality data from a well-studied coral reef fish species, the Caribbean bridled goby Coryphopterus glaucofraenum, substantially better than do several mortality functions of more conventional form.