Assessment of (un)sustainability of EU harvest of migratory birds in non‐secure conservation status: Bridging science and policy

Hunting may affect wildlife, yet there is still limited knowledge (particularly outside North America) about how sustainable hunting can be at the population level. In Europe, out of 84 huntable bird species (after Annex II of the European Union [EU] Birds Directive), 42 are in a non‐secure conservation status. The Birds Directive states that hunting in such cases can only be considered as part of a management plan accompanied by recovery measures. In this context, assessing whether hunting levels are sustainable is critical.

We assessed sustainability of current EU hunting levels for 27 bird migratory species in non‐secure conservation status, using Demographic Invariant Models. We used the R package popharvest to calculate a Sustainability Harvest Index (SHI). SHI compares the actual offtake with the Potential Take Level (calculated from demographic parameters and population size), modulated by a factor related to management objectives, F _obj . We tested all F _obj values between 0 and 1 by 0.01 steps, and present results using a traffic light system: red light was assigned to situations where SHI exceeded 1 in >50% of simulations for F _obj <0.75, that is, clear unsustainability under either liberal to conservative management.

Current harvest levels within the EU are likely to be unsustainable for at least one population in each of six species (five ducks and one landbird), and possibly unsustainable in at least one population for three other species (one wading bird, one gull, one landbird). In four duck species, recent winter population trends seem to contradict the results, highlighting the need for better information on population abundance, harvest and flyway delineation.

Synthesis and applications . Our results allow the identification of the species/populations most likely to be overharvested in the EU, requiring management considerations to ensure compliance with the Birds Directive. Our approach allows us to separate science from policy considerations, facilitating stakeholder discussion and agreement on which species should be prioritized for management.