title: Taylor's law and body size in exploited marine ecosystems.
abstract: Taylor's law (TL), which states that variance in population density is related to mean density via a power law, and density-mass allometry, which states that mean density is related to body mass via a power law, are two of the most widely observed patterns in ecology. Combining these two laws predicts that the variance in density is related to body mass via a power law (variance-mass allometry). Marine size spectra are known to exhibit density-mass allometry, but variance-mass allometry has not been investigated. We show that variance and body mass in unexploited size spectrum models are related by a power law, and that this leads to TL with an exponent slightly <2. These simulated relationships are disrupted less by balanced harvesting, in which fishing effort is spread across a wide range of body sizes, than by size-at-entry fishing, in which only fish above a certain size may legally be caught.
authors.affiliation: Laboratory of Populations, Rockefeller & Columbia Universities New York, New York.
authors.forename: Joel E
authors.initials: JE
authors.lastname: Cohen
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Plank
authors.forename: Richard
authors.initials: R
authors.lastname: Law
keywords: Balanced harvesting; density-mass allometry; fishing; power law; size spectrum; size-at-entry; variance-mass allometry