Invasive species are known to cause significant negative impacts to ecosystems and to people. In this paper, we outline the nature of these economic impacts, and then present a range of approaches for estimating the economic costs of invasive species (including impacts on biodiversity), and thus the benefits of management programmes. The importance of thinking clearly about the most appropriate context for valuation is stressed. We provide examples of the application of non‐market valuation approaches to invasive species management, and show how such methods can be used to measure public preferences over how control is undertaken. We discuss some important problems in applying economic valuation methods in this context. A plain language summary is available for this article.

Conservation conflict is widespread, damaging, and has proved difficult to manage using conventional conservation approaches. Conflicts are often “wicked problems,” lacking clear solutions due to divergent values of stakeholders, and being embedded within wickedly complex environments. Drawing on the concept of wicked environmental problems could lead to management strategies better suited to tackling conflict. However, it is unclear whether managers are embracing ideas from the wicked problems concept. There is currently a lack of guidance for applying strategies to tackle particular wicked problems, such as conservation conflict. We explored the suitability of wicked problems‐inspired management, using eight contemporary conflict case studies. Conservation conflict was managed predominantly using conventional approaches suited to tackling single objectives in simple environments, rather than balancing competing objectives in complex environments. To deal with different characteristics of wickedness, we recommend that managers develop strategies combining distributed decision‐making, diverse opinions, pattern‐based predictions, trade‐off‐based objectives, and reporting of failures. Recent advances in conservation conflict research have focused on improving interactions among stakeholders. We believe that such stakeholder‐focused approaches would dovetail with the whole‐system focus of a wicked problems framework, allowing conservationists to move toward a holistic strategy for managing conservation conflict.

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Coral reefs are in decline worldwide. While coral reef managers are limited in their ability to tackle global challenges, such as ocean warming, managing local threats can increase the resilience of coral reefs to these global threats. One such local threat is high sediment inputs to coastal waters due to terrestrial over-grazing. Increases in terrestrial sediment input into coral reefs are associated with increased coral mortality, reduced growth rates, and changes in species composition, as well as alterations to fish communities. We used general linear models to investigate the link between vegetation ground cover and tree biomass index, within a dryforest ecosystem, to coral cover, fish communities and visibility in the case study site of Bonaire, Caribbean Netherlands. We found a positive relationship between ground cover and coral cover below 10m depth, and a negative relationship between tree biomass index and coral cover below 10m. Greater ground cover is associated to sediment anchored through root systems, and higher surface complexity, slowing water flow, which would otherwise transport sediment. The negative relationship between tree biomass index and coral cover is unexpected, and may be a result of the deep roots associated with dry-forest trees, due to limited availability of water, which therefore do not anchor surface sediment, or contribute to surface complexity. Our analysis provides evidence that coral reef managers could improve reef health through engaging in terrestrial ecosystem protection, for example by taking steps to reduce grazing pressures, or in restoring degraded forest ecosystems.

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Invasive pathogens threaten the ability of forests globally to produce a range of valuable ecosystem services over time. However, the ability to detect such pathogen invasions-and thus to produce appropriate and timely management responses-is relatively low. We argue that a promising approach is to plan and manage forests in a way that increases their resilience to invasive pathogens not yet present or ubiquitous in the forest. This paper is based on a systematic search and critical review of empirical evidence of the effect of a wide range of forest management options on the primary and secondary infection rates of forest pathogens, and on subsequent forest recovery. Our goals are to inform forest management decision making to increase forest resilience, and to identify the most important evidence gaps for future research. The management options for which there is the strongest evidence that they increase forest resilience to pathogens are: reduced forest connectivity, removal or treatment of inoculum sources such as cut stumps, reduced tree density, removal of diseased trees and increased tree species diversity. In all cases the effect of these options on infection dynamics differs greatly amongst tree and pathogen species and between forest environments. However, the lack of consistent effects of silvicultural systems or of thinning, pruning or coppicing treatments is notable. There is also a lack of evidence of how the effects of treatments are influenced by the scale at which they are applied, e.g., the mixture of tree species. An overall conclusion is that forest managers often need to trade-off increased resilience to tree pathogens against other benefits obtained from forests.

Deglacial sea-level index points defining relative sea-level (RSL) change are critical for testing glacial isostatic adjustment (GIA) model output. Only a few observations are available from North Wales and until recently these provided a poor fit to GIA model output for the British-Irish Ice Sheet. We present results of an integrated offshore geophysical (seismic reflection), coring (drilling rig), sedimentological, micropalaeontological (foraminifera), biostratigraphical (palynology) and geochronological (AMS 14 C) investigation into a sequence of multiple peat/organic sediment horizons interbedded within a thick estuarine-marine sequence of minerogenic clay-silts to silty sands from the NE Menai Strait, North Wales. Ten new sea-level index points and nine new limiting dates from the Devensian Late-glacial and early Holocene are integrated with twelve pre-existing Holocene sea-level index points and one limiting point from North Wales to generate a regional RSL record. This record is similar to the most recent GIA predictions for North Wales RSL change, supporting either greater ice load and later deglaciation than in the GIA predictions generated before 2004, or a modified eustatic function. There is no evidence for a mid-Holocene highstand. Tidally corrected RSL data indicate initial breaching of the Menai Strait between 8.8 and 8.4 ka BP to form a tidal causeway, with final submergence between 5.8 and 4.6 ka BP. Final breaching converted the NE Menai Strait from a flood-dominated estuary into a high energy ebb tidal delta with extensive tidal scouring of pre-existing Late-glacial and Holocene sequences. The study confirms the value of utilising offshore drilling/coring technology to recover sea-level records which relate to intervals when rates of both eustatic and isostatic change were at their greatest, and therefore of most value for constraining GIA models.

While ecological links between ecosystems have been long recognised, management rarely crosses ecosystem boundaries. Coral reefs are susceptible to damage through terrestrial run-off, and failing to account for this within management threatens reef protection. In order to quantify the extent to that coral reef users are willing to support management actions to improve ecosystem quality, we conducted a choice experiment with SCUBA divers on the island of Bonaire, Caribbean Netherlands. Specifically, we estimated their willingness to pay to reduce terrestrial overgrazing as a means to improve reef health. Willingness to pay was estimated using the multinomial, random parameter and latent class logit models. Willingness to pay for improvements to reef quality was positive for the majority of respondents. Estimates from the latent class model determined willingness to pay for reef improvements of between $31.17 - $413.18/year, dependent on class membership. This represents a significant source of funding for terrestrial conservation, and illustrates the potential for user fees to be applied across ecosystem boundaries. We argue that such across-ecosystem-boundary funding mechanisms are an important avenue for future investigation in many connected systems.