title: An empirical assessment of the focal species hypothesis.
abstract: Biodiversity surrogates and indicators are commonly used in conservation management. The focal species approach (FSA) is one method for identifying biodiversity surrogates, and it is underpinned by the hypothesis that management aimed at a particular focal species will confer protection on co-occurring species. This concept has been the subject of much debate, in part because the validity of the FSA has not been subject to detailed empirical assessment of the extent to which a given focal species actually co-occurs with other species in an assemblage. To address this knowledge gap, we used large-scale, long-term data sets of temperate woodland birds to select focal species associated with threatening processes such as habitat isolation and loss of key vegetation attributes. We quantified co-occurrence patterns among focal species, species in the wider bird assemblage, and species of conservation concern. Some, but not all, focal species were associated with high levels of species richness. One of our selected focal species was negatively associated with the occurrence of other species (i.e., it was an antisurrogate)-a previously undescribed property of nominated focal species. Furthermore, combinations of focal species were not associated with substantially elevated levels of bird species richness, relative to levels associated with individual species. Our results suggest that although there is some merit to the underpinning concept of the FSA, there is also a need to ensure that actions are sufficiently flexible because management tightly focused on a given focal species may not benefit some other species, including species of conservation concern, such of which might not occur in species-rich assemblages.
authors.affiliation: Fenner School of Environment and Society, ARC Centre of Excellence for Environmental Decisions; and National Environmental Research Program, The Australian National University, Canberra, ACT, 0200, Australia.
authors.forename: D B
authors.initials: DB
authors.lastname: Lindenmayer
authors.forename: P W
authors.initials: PW
authors.lastname: Lane
authors.forename: M J
authors.initials: MJ
authors.lastname: Westgate
authors.forename: M
authors.initials: M
authors.lastname: Crane
authors.forename: D
authors.initials: D
authors.lastname: Michael
authors.forename: S
authors.initials: S
authors.lastname: Okada
authors.forename: P S
authors.initials: PS
authors.lastname: Barton
mesh_terms: D063147:Animal Distribution; D000818:Animals; D044822:Biodiversity; D001717:Birds / Q000502:physiology*; D003247:Conservation of Natural Resources / Q000379:methods*; D065928:Forests; D009517:New South Wales
keywords: Anti-sustitutos; Biodiversity surrogates; anti surrogates; aves de bosque amenazadas; conservation practice; práctica de la conservación; sustitutos de la biodiversidad; threatened woodland birds