A whole-genome approach to resolve the genetic structure of Antipodean and Gibson’s albatross populations
Imogen Foote1*, Geoffrey K Chambers1, Igor Debski2, Graham Elliott2, Graham Parker3, Nicolas J Rawlence4, Kalinka Rexer-Huber3, Kath Walker2, Peter A Ritchie1
1Victoria University of Wellington, School of Biological Sciences, Level 2 Te Toki a Rata Building, Wellington 6012
imogen.foote@vuw.ac.nz (*PhD student); geoff.chambers@vuw.ac.nz; peter.ritchie@vuw.ac.nz
2Department of Conservation, PO Box 10420, Wellington 6140
idebski@doc.govt.nz; kwalker@doc.govt.nz; gelliott@doc.govt.nz
3Parker Conservation, 126 Maryhill Terrace, Dunedin 9011
kalinka.rexerhuber@gmail.com; g.parker@parkerconservation.co.nz
4University of Otago, Department of Zoology, 340 Great King Street, Dunedin 9016
nic.rawlence@otago.ac.nz
Although seabirds are a comparatively well studied group, a major barrier to their conservation is the taxonomic uncertainty that exists across many groups. For instance, albatrosses (family Diomedeidae) have been subject to several taxonomic revisions, but debate is ongoing. Genetic datasets have been used to inform albatross taxonomy, but only a handful of low-resolution genetic markers have been used, limiting the power to delineate species boundaries. Recently, genome-wide DNA sequencing has become more accessible, and this type of genomic data can greatly improve species-level taxonomic resolution. The Antipodean albatrosses of New Zealand presently comprise two subspecies, the Antipodean albatross (Diomedea antipodensis antipodensis) and Gibson’s albatross (D. a. gibsoni). Both taxa are highly threatened, due largely to mortality associated with fisheries bycatch, and the populations continue to decline. Long-term population monitoring has revealed several differences between them; when the sex is known they can be distinguished morphologically, they have distinct foraging ranges and their breeding seasons differ temporally by several weeks, yet based on current genetic data they are considered one Evolutionary Significant Unit (ESU). We are presently assembling a reference genome for both the Antipodean and Gibson’s albatross. We intend to use genome-wide SNP data to determine the level of genetic differentiation between these two subspecies and estimate demographic parameters such as genetic diversity and effective population size for each taxon. The findings from this study should help to better define species and population units, inform conservation management and provide fertile ground for further conservation genomic studies of albatross.