Genetics at the verge of extinction: insights from the Iberian lynx

Abstract

Population viability might become compromised by the loss of genetic diversity and the accumulation of inbreeding resulting from population decline and fragmentation. The Iberian lynx (Lynx pardinus) provides a paradigmatic example of a species at the verge of extinction, and because of the well-documented and different demographic histories of the two remaining populations (Doñana and Andújar), it provides the opportunity to evaluate the performance of analytical methods commonly applied to recently declined populations. We used mitochondrial sequences and 36 microsatellite markers to evaluate the current genetic status of the species and to assess the genetic signatures of its past history. Mitochondrial diversity was extremely low with only two haplotypes, alternatively fixed in each population. Both remnant populations have low levels of genetic diversity at microsatellite markers, particularly the population from Doñana, and genetic differentiation between the two populations is high. Bayesian coalescent-based methods suggest an earlier decline starting hundreds of years ago, while heterozygosity excess and M-ratio tests did not provide conclusive and consistent evidence for recent bottlenecks. Also, a model of gene flow received overwhelming support over a model of pure drift. Results that are in conflict with the known recent demography of the species call for caution in the use of these methods, especially when no information on previous demographic history is available. Overall, our results suggest that current genetic patterns in the Iberian lynx are mainly the result of its recent decline and fragmentation and alerts on possible genetic risks for its persistence. Conservation strategies should explicitly consider this threat and incorporate an integrated genetic management of wild, captive and re-introduced populations, including genetic restoration through translocations.

Population and genetic outcomes 20 years after reintroducing bobcats (Lynx rufus) to Cumberland Island, Georgia USA

“…2012; Casas‐Marce et al. 2013). These species had H O prior to reintroduction or translocation programs that varied from 0.167 for the Florida panther, (Johnson et al.…”

“…2012; Casas‐Marce et al. 2013). There are two remaining remnant populations of the Iberian lynx, which show evidence of inbreeding depression, including reduced genetic diversity (Palomares et al.…”

“…Therefore, translocations and supplementation of wild populations with captive‐bred individuals may be necessary for long‐term conservation of this species (Casas‐Marce et al. 2013). …”

Reassessment of the conservation status of the Iberian lynx Lynx pardinus for the IUCN Red List of Threatened Species

“…Such separation is at least five times the maximum successful dispersal distance (Ferreras et al 2004) and, indeed, no individual born in one subpopulation has been reported to settle into the other by natural means. A marked genetic differentiation further supports demographic isolation between both subpopulations for at least ten generations (Casas-Marcé et al 2013). As >50% of total AOO is placed in a single isolated locality that might not support a viable population, the geographic range of the Iberian lynx can be considered as severely fragmented (IUCN Standards and Petitions Subcommittee 2014).…”

Potential of genomic approaches in conservation of plant and animal biodiversity in Africa: A review

“…For example, the population with specific adaptive alleles can be identified and used to supplement the endangered population or reintroducing species into the habitat in which the natural population has vanished (Simpson et al 2017). The loss of genetic diversity and inbreeding accumulation due to fragmentation and decrease of population may compromise the viability of population (Casas-Marce et al 2013). An example of organism showing this is the Iberian lynx (Lynx pardinus) which is in the edge of extinction (Godoy, 2016).…”