Hibridación entre la codorniz común (Coturnix coturnix) y la codorniz de granja: estado de un problema de conservación

Abstract

Background:The common quail, Coturnix coturnix, is a migratory bird hunted extensively across Europe. To satisfy this hunting interest, thousands of farm-reared birds are restocked every year. However, restocked individuals are not common quail but hybrids with domestic Japanese quail, C. japonica. Interbreeding between restocked and native birds in the wild allows the entry of alien alleles to the native populations, which could lead to the loss of adaptive phenotypes and behaviours, such as migratory drive. Sedentary individuals may face wintering conditions to which they are not adapted, suffering higher mortality. Some individuals have been observed to remain in northern latitudes during winter.Question: Does game restocking contribute to the sedentarization of the common quail population?Method: We sampled 42 quail during the autumn migration and 50 quail during winter in Spain. We genetically analysed them using a set of autosomal microsatellites and also sequenced a fragment of the mitochondrial DNA control region. We evaluated the proportion of admixed quail found and compared it with that previously found in a breeding population.Results: None of the migratory quail were admixed individuals, although two of them showed introgression of Japanese mitochondrial DNA. Among wintering quail, only three individuals had a genetic composition compatible with a farm origin, while the rest were common quail. Thus, the proportion of admixed quail during winter was not higher than during the breeding season.Conclusion: Restocking individuals with domestic Japanese quail ancestry is not directly associated with the presence of quail during winter in northern latitudes. The almost complete absence of individuals of farm origin among the migratory and wintering quail populations indicates that the vast majority of the restocked individuals probably die soon after release.

Detecting slow introgression of invasive alleles in an extensively restocked game bird

“…This would be possible if most of the admixed individuals were not involved in the reproduction. However, this does not seem likely because field experiments have shown that female quails of farm origin are more successful than wild common quails in attracting and mating wild common quail males (Puigcerver et al, 1999(Puigcerver et al, , 2013(Puigcerver et al, , 2014. The limited introgression of farm alleles into the wild population may be due to the lower fitness of the released birds and their descendants, which is also supported by experimental observations in the wild that point to a decreased survival and increased nest predation for females of farm origin (Puigcerver et al, 2014).…”

“…and Manel Puigcerver). It is an open population and individuals continuously arrive during the breeding season, spend some time, and leave in search of suitable habitat patches and mates (Puigcerver et al, 1989;Rodríguez-Teijeiro et al, 2006, 2009. This is a game area, and the hunting season starts in mid-August, after the end of the breeding season (from about mid-April to early July).…”

“…Its European breeding population is estimated to consist of several millions of individuals (8,400,000-14,100,000, BirdLife International, 2004) that move nomadically across the breeding range looking for suitable habitat (Puigcerver et al, 1989;Rodríguez-Teijeiro et al, 2009) and mates (Rodríguez-Teijeiro et al, 2006). This game species is of high economic and recreational interest in southern Europe; millions of quails are killed every hunting season (Guyomarc'h, 2003).…”

El problema de la caza visto por un genetista

“…Existe evidencia de hibridación de codorniz común (Coturnix coturnix) con codorniz japonesa de corral (Coturnix japonica) y que esta hibridación se ha producido artificialmente en granjas cinegéticas. Una vez en el medio natural, los individuos híbridos podrían a su vez cruzarse con codorniz común (ver una reciente revisión sobre el tema en Puigcerver et al, 2013). Los efectos de la suelta de individuos híbridos pueden ser muy perjudiciales para la codorniz común, por ejemplo, porque los primeros suelen tener tendencias sedentarias.…”

Gestión cinegética y conservación: aspectos ecológicos, problemáticas y retos de futuro

“…En esta línea, Puigcerver et al (2013) abordan el caso de la codorniz común (Coturnix coturnix), la cual podría verse amenazada por la suelta de individuos híbridos con codorniz japonesa (Coturnix japonica), o directamente por ejemplares de esta última especie, que se reproduce mucho mejor en cautividad que la especie autóctona. Los principales riesgos de estas sueltas pasan por fenó-menos de introgresión genética que pueden afectar a la ecología de la especie y provocar un colapso de las poblaciones nativas.…”