Genomic Resources for the Management and Conservation of Bald and Golden Eagles

Delineating the biologically relevant boundaries within a species’ range should constitute the first step in any conservation or management program. This critical step informs the wildlife managers, biologists, and policy... [ view full abstract ]

Delineating the biologically relevant boundaries within a species’ range should constitute the first step in any conservation or management program. This critical step informs the wildlife managers, biologists, and policy makers of the “units” they are attempting to conserve or manage while also setting the biological and theoretical foundations for future decisions. Unfortunately, elucidating the genetic variation within and among populations of Bald (Haliaeetus leucocephalus) and Golden (Aquila chrysaetos) eagles has proven exceedingly challenging. Currently, U.S. Fish and Wildlife are managing these species either via Eagle Management Units, which are different for the two species or via flyways, which are the same for both species. However, the existence of discrete population units for either species, if they exist, has yet to be evaluated with genetic data. The purpose of this study was to utilize a genomic approach to evaluate these competing hypotheses for eagle management units as well as a purely genetically based delineation of eagle populations. Addressing this overarching objective will allow for mitigation of population losses due to unintended “takes” of eagles at wind farms by determining the individuals natal origin. Utilizing a reduced genomic sequencing of 200 bald eagle genomes and 32 golden eagle genomes resulted in approximately 1.5 million genetic loci (Single Nucleotide Polymorphisms [SNPs] per species and preliminary population genomic analysis of 21,259 bald eagle SNPs and 30,006 golden eagle SNPs provided contrasting pictures of population subdivision that we interpret as being related to historical anthropogenic factors but provided evidence for continuing with this approach. We therefore reduced the initial 1.5 million SNPs per species to 50,054 bald eagle SNPs and 37,562 golden eagle SNPs. These 87,616 SNPs have been place on a SNP Chip and represent coding and intergenic regions of the genome. This study represents the first population genomics approach for bald and golden eagles and the development of these species specific SNP Chips will allow for the delineation of biologically relevant population boundaries as well as assign individuals of unknown origin to their natal area.