Listing may not achieve conservation: A call for proactive approaches to threatened species management

Abstract

Species listing and subsequent conservation efforts are dependent on a number of political, social, and scientific factors, often to the disadvantage of uncharismatic taxa, such as small, cryptic, and rare species, and those that lack commercial value. This case study examined the listing, impact assessment and conservation process of the critically endangered marine seaweed Nereia lophocladia (Nereia hereafter), which is a small and sporadically occurring species. Nereia was initially listed as vulnerable, and upgraded to critically endangered, following the precautionary principle. Despite the elevation of its listing and the existence of a recovery plan, little conservation effort was devoted to Nereia. A major upgrade to a large breakwater adjacent to Nereia's only known location triggered legislation and targeted searches for the species. Once found at the site, adaptive management actions, including modifications to the breakwater and some of the first targeted scientific surveys for this species took place. The targeted surveys quickly revealed a far greater population of Nereia with a broader distribution than was previously realized. Given this, the breakwater upgrade probably caused less extinction risk to Nereia than predicted and a costly redesign may not have been necessary to secure the species' survival. The case study argues for a proactive, evidentiary approach to species conservation, where conservation actions should be initiated as soon as species are listed and not when an immediate risk of extinction arises. Such approaches would improve conservation efforts and may also reduce the overall costs of saving species

Conservation genomics of a critically endangered brown seaweed

“…However, non‐detection at a particular site does not necessarily imply absence due to Nereia 's alternation of generations life history and patchiness (for details, see Mamo et al. 2019). Geographic range size mediates a species' extinction risk, with a more extensive range reducing the likelihood of stochastic or direct pressures affecting all individuals (Gaston and Fuller 2009, Wootton and Pfister 2013).…”

“…Preliminary survey results suggested that Nereia may be distributed further afield than previously thought (Kelaher and Mamo 2018, Mamo et al. 2019), with significant implications for the conservation of this critically endangered species. Here, we combine field surveys to assess Nereia 's wider distribution, with the characterization of genetic diversity, population structure, and candidate loci under putative selection.…”

“…2017, Mamo et al. 2018, 2019), including a long‐term monitoring program to fill knowledge gaps in the species' conservation Action Plan (DPI 2016) and inform management actions surrounding the breakwater upgrade to maximize conservation outcomes (Yee et al. 2017).…”

A Contrast of Criteria for Special Places Important for Biodiversity Outcomes

“…Over recent decades, there has been increasing recognition of the importance of enhancing the priority given to conservation of places that have special importance for biodiversity (Lopoukhine and Ferreira de Souza Dias, 2012;Ovando et al, 2021). Various types of biodiversity features may contribute to an area's prioritization for enhanced risk aversion in management, including the presence of rare or vulnerable species (Walsh et al, 2013, Mamo et al, 2020, exceptional structural complexity and/or diversity of habitat features (Airoldi et al, 2008;Lipcius et al, 2019), critical functional significance such as the role of the areas as a migration corridor (Boulton et al, 2016;Lederhouse and Link, 2016), or simply by being in a comparatively undisturbed state (Bryan et al, 2011;Bax et al, 2016). Particular sites may be proposed as a priority for enhanced risk aversion due to even a single one of these types of features, but the features also may occur in a variety of combinations.…”

Small‐bodied fish species from the western United States will be under severe water stress by 2040

“…Endangered species (e.g., listed under the Endangered Species Act; ESA), often tend to be obscure and insufficiently studied both in terms of their distribution or roles within ecosystems and ecosystem components (Cooke et al, 2012). Many of these species get listed in a reactionary approach on a regional level after often irreversible impacts have been done or cascading ecosystem effects have been set in motion (Bush et al, 2014; Mamo et al, 2019). Consequently, an overuse of biodiversity as a conservation priority indicator could potentially inadequately cover low diversity but high‐risk and high‐pressure regions, as biodiversity does not necessarily coincide with at‐risk species, or species with unique life history or distribution patterns (Bush et al, 2014; Mamo et al, 2019).…”