Graduate student Natalie Hoffmeister just returned from a pilot field season chasing after Imperial Shags in Patagonia, and she’s now even more eager to return for another season of sampling. This project may grow into her dissertation, focusing on population structure and salt tolerance in (Phalacrocorax atriceps) near Ushuaia, Tierra del Fuego, Argentina. Previous work by Argentine ornithologists Gustavo Sebastián Cabanne and Luciano Calderon—who visited the Lovette Lab in 2013 and 2015 respectively—suggests that a remote freshwater population in Tierra del Fuego may be genetically differentiated from all other populations. Natalie is now collaborating with Pablo Tubaro and Gustavo Sebastián Cabanne at the Museo Argentino de Ciencias Naturales to investigate whether freshwater shags have differentiated from coastal birds and whether this differentiation reflects adaptation to this novel environment.
Natalie discovered that, as expected, the freshwater P. atriceps are quite different, but the only difference she measured this season was in their phenology. Shags in the Beagle Channel (which is less than 50 km from the lakes) had chicks in mid-December, but even now the freshwater birds are showing no signs of mating or breeding. Adult shags are flighty beasts, but she’s going to practice her army crawl for the next year. Her collaborators in Tierra del Fuego continue to be incredibly helpful and are monitoring these freshwater shags and their breeding activity.