Trait-Based Specific Protection Goals for Wild Pollinators: A Staged Modelling Framework for Pesticide Risk Assessment

Publication category: Preprint

Authors: Christopher Topping, Andreas Focks, Serio Albacete González, Celeste Azpiazu Segovia, and 56 more

Publication date: 15 August 2026

DOI: https://doi.org/10.21203/rs.3.rs-10019161/v1

Language: English

Abstract:

Background Wild pollinator populations in the European Union lack defined, quantitative Specific Protection Goals (SPGs) for pesticide risk assessment. Without an agreed threshold, lower-tier toxicity data cannot be evaluated for acceptability, nor can higher-tier study results be assessed against a protection goal, leaving the tiered ERA process at an impasse. The existing honey bee surrogate compounds the problem: this was selected for laboratory convenience rather than functional representativeness, and their managed, colonial life history cannot reliably predict outcomes for the diverse life-history strategies of wild pollinators.

Results This paper presents a pragmatic, staged framework combining trait-based species selection with demographic toxicity assessment. It focuses on Stage 1 (non-spatial) of a the three-stage process, where life-stage-structured population models are implementable now (2026–2027), uses existing data and tools, and generates quantitative, population-level SPG thresholds within the current [1] tiered assessment framework. The framework combines two methodological advances: trait-based species selection identifies functionally vulnerable species by grouping taxa according to exposure- and sensitivity-related traits and population resilience; and demographic toxicity assessment translates individual-level pesticide effects into population-level outcomes through life-stage-structured projection matrices. Parameter space exploration demonstrates that Stage 1 yields defined, quantitative thresholds: a maximum acceptable population decline and a maximum acceptable exceedance risk probability.

Conclusions Stage 1 resolves the immediate operational constraint by providing provisional, population-level thresholds for regulatory use. A roadmap for adaptive implementation and progressive refinement is provided: Stage 2 (operational 2028–2029) incorporates landscape-scale spatial dynamics, and Stage 3 (operational 2030+) implements full agent-based modelling using the ALMaSS system. The approach is demonstrated for bees (bumble bees and solitary bees), but the trait-based framework is designed to be flexible enough to generalise across hoverflies, butterflies, moths, and other pollinating taxa.

Cite this article: Christopher Topping, Andreas Focks, Serio Albacete González et al. Trait-Based Specific Protection Goals for Wild Pollinators: A Staged Modelling Framework for Pesticide Risk Assessment, 25 June 2026, PREPRINT (Version 1) available at Research Square [https://doi.org/10.21203/rs.3.rs-10019161/v1]