Evaluating the Effectiveness of a Conservation Project on Two Threatened Birds: Applying Expert-Based Threat Analysis and Threat Reduction Assessment in a Mediterranean Wetland

Abstract

We applied two recent approaches largely used in biological conservation: Threat Analysis (TAN) and Threat Reduction Assessments (TRAs), assessing the effectiveness of a project focused on two water-related bird species (common tern, Sterna hirundo and little tern, Sternula albifrons), commonly breeding in some wetlands of Italy. We used the IUCN standardized lexicon for the classification of threats, utilizing a panel of experts to assess a set of regime attributes (extent, severity and magnitude) of each human-induced disturbance. Our aims were: (i) through the TAN approach, to carry out an arrangement and quantification of the main threats acting on our focal species and select the priority ones; (ii) through the TRA approach, to test the effectiveness of an operational project focused on mitigating the threats and improving the breeding success of species (i.e., building rafts and floating islands to encourage their nesting). Using the TAN approach, experts identified the following human-induced threats (IUCN code): 6.1—Generic disturbance; 7.2—Water stress; 7.3—Salinization; 8.8—Vagrant dogs; 8.8—Mediterranean gulls; 8.8—Wild boars, all significantly different in their magnitude. Among them, wild boars and Mediterranean gulls appeared the priority threats with the greatest extent, intensity and magnitude. Using the TRA approach, after the project, we assessed an overall decrease in the threat magnitude of 23.08% (21.42% when considering only the threats directly affected by our project). These data suggest that further efforts should be devoted to achieving greater effectiveness of conservation actions focused on our target species. With limited time and resources to quantify threats, expert-based approaches could be useful for rapidly assessing the effectiveness of small conservation projects by providing a range of scores obtained following an analytical procedure. In this regard, Threat Analysis and Threat Reduction Assessment could be considered useful tools to support adaptive management in project management cycles.

Searching priorities for a species at the brink of extinction: Threats analysis on the critically endangered Nubian Flapshell Turtle (Cyclanorbis elegans)

“…Consequently, TA serves as a valuable tool for conservation strategies, especially in contexts like nature reserves or projects focused on given threatened species in crisis situations (e.g. AlHirsh et al, 2016;Battisti et al, 2008Battisti et al, , 2009Battisti et al, , 2020Battisti et al, , 2023Bauer et al, 2022;Giovacchini et al, 2022;Jarvis et al, 2010).…”

Beyond Protected Areas: Assessing Management Effectiveness of a Ramsar Site in Nepal

“…We used the threats classification from the International Union for Conservation of Nature and Conservation Measures Partnership (IUCN-CMP) classification of direct threats [37]. This has been adopted by the R-METT and has also been used to assess threats to wetland and wetland-dependent birds [38,39]. The score of the threats were assigned as either low, medium, high or not applicable depending on the severity and scope of the threats.…”

Combining resilience and resistance with threat‐based approaches for prioritizing management actions in sagebrush ecosystems

“…More challenging are the chronic, expanding threats to ecosystems and increases in habitat modification resulting from greater environmental stochasticity due to a warming climate, species invasions, and altered disturbance regimes. For example, in terrestrial ecosystems experiencing progressive invasions of flammable grasses and development of grass-fire cycles, it may not be possible to completely remove the threat and stop its expansion (Rossiter et al, 2003;D'Antonio et al, 2011;Gorgone-Barbosa et al, 2015;Fusco et al, 2019;Pausas & Keeley, 2021;Kleinhesselink et al, 2023).…”

“…The capacity of a system to recover following removal of threats or changes in management to address threats depends on several factors, including the nature of the threat, the ecological resilience of the system to the threat, and ongoing changes in climate. Threat management is often most successful when individual, specific threats to species, such as predators, pollutants, or over‐utilization have been removed from the system or managed successfully (e.g., Giovacchini et al, 2022). More challenging are the chronic, expanding threats to ecosystems and increases in habitat modification resulting from greater environmental stochasticity due to a warming climate, species invasions, and altered disturbance regimes.…”