Is maximizing protection the same as minimizing loss? Efficiency and retention as alternative measures of the effectiveness of proposed reserves

Abstract

We used two measures to compare the effectiveness of 52 conservation criteria in achieving conservation targets for forest types. The first measure was efficiency. Although widely used, efficiency assumes no loss or reduction of biodiversity features before conservation is implemented. This is invalid in many situations. Often, it is more realistic to assume gradual implementation accompanied by incremental, predictable reduction and loss of biodiversity features. We simulated future landscapes resulting from the annual interplay of loss and conservation of forest types. We then based our second measure, retention, on how well criteria scheduled conservation action to prevent targets being compromised. The simulations partly support predictions about the best criteria for scheduling implementation with continuing biodiversity loss. Retention was weakly related or unrelated to efficiency across 52 criteria. Although retention values were sensitive to changes in targets and rates of conservation and forest loss, one criterion consistently produced highest retention values.

When do conservation planning methods deliver? Quantifying the consequences of uncertainty

“…Various works have shown the consequences of mistakenly assuming that the reserve selection occurs all at once (Costello and Polasky, 2004;Meir et al, 2004;Pressey et al, 2004;Drechsler, 2005) or that habitat outside reserves is lost immediately (Cabeza and Moilanen, 2003) but these consequences are generally ignored in conservation planning methods. In Experiment 3 (Fig.…”

“…Some studies investigate uncertainty in the species maps used in the reserve selection (Gaston and Rodrigues, 2003;Wilson et al, 2005;Halpern et al, 2006;Ray and Burgman, 2006;Rondinini et al, 2006;vanTeeffelen et al, 2006). Other studies examine sequential decisions and issues associated with loss and availability of habitat over time as opposed to immediately implementing an entire reserve network (Costello and Polasky, 2004;Meir et al, 2004;Pressey et al, 2004;Drechsler, 2005;Sarkar et al, 2006;Turner and Wilcove, 2006). Rodrigues et al (2000) and Araujo et al (2004) address temporal issues associated with variability in population locations due to climate change.…”

Designing Climate-Resilient Marine Protected Area Networks by Combining Remotely Sensed Coral Reef Habitat with Coastal Multi-Use Maps

“…Because the distribution of biodiversity is a fundamental prerequisite for determining the location and size of managed areas, identifying representative or distinctive habitats, and assessing their conservation status, has proven challenging in the WIO [14]. An alternative strategy that evaluates remotely-sensed identifiable habitats, their characteristics and distribution can reduce this data-limitation problem and assist management planning [15,16].…”

Addressing longitudinal connectivity in the systematic conservation planning of fresh waters

“…After defining clear objectives (such as biodiversity targets), they look for areas that add as many under-represented surrogates (taxa or any other conservation feature) as possible to a network of protected areas (Pressey, Possingham & Day, 1997), achieving the efficiency goal by selecting as few areas as possible that together reach the representativeness goal (Pressey & Nicholls, 1989). However, the identification of single reserve solutions is a rigid strategy which gives no indication on the importance of each area in terms of their potential to be replaced by other available areas in the region (Pressey, Watts & Barret, 2004) and the value of unselected areas . To include flexibility in systematic conservation planning, quantitative conservation tools often incorporate measures of irreplaceabilitycalculated by estimating the likelihood that an area will be required to meet a given set of targets Ferrier et al, 2000).…”