Captive breeding cannot sustain migratory Asian houbara Chlamydotis macqueenii without hunting controls

Abstract

To evaluate the potential contribution of captive breeding to the conservation of exploited migratory Asian houbara Chlamydotis macqueenii, we estimated release numbers required to stabilise a population in a hunting concession (14,300 km2), under scenarios of local licensed hunting and flyway-scale protection. We developed a population model, initially 2350 adult females, re-sampling parameters measured through fieldwork and satellite telemetry, over 1000 iterations. With current flyway-scale unregulated harvest, and without any licensed hunting in the concession, populations declined at 9.4% year−1 (95% CI: −18.9 to 0% year−1); in this scenario a precautionary approach (85% probability λ ≥ 1.0) to population stabilisation required releasing 3100 captive-bred females year−1 (131% of initial wild numbers). A precautionary approach to sustainable hunting of 100 females year−1 required releasing 3600 females year−1 (153% of initial wild numbers); but if interventions reduced flyway-scale hunting/trapping mortality by 60% or 80%, sustaining this quota required releasing 900 or 400 females year−1, 38% and 17% of initial wild numbers, respectively. Parameter uncertainty increased precautionary numbers for release, but even with reduced precaution (50% probability λ ≥ 1.0), sustainable hunting of 100 females year−1 required annual releases of 2200 females (94% wild) without other measures, but 300 (13%) or no (0%) females under scenarios of a 60% or 80% reduction in flyway-scale hunting/trapping. Captive breeding cannot alone sustain migrant populations of wild C. macqueenii because it risks replacement and domestication. Trade and exploitation must be restricted to avoid either extinction or domestication. For exploited populations, supplementation by captive breeding should be used with caution.