Marcela Liljesthröm

My research...

study species

Rockhopper Penguins (Eudyptes chrysocome) breed on sub-Antarctic and temperate islands and are one of the most abundant penguin species. However, over the past 70 years, the population has undergone considerable declines at most of the islands where they nest. The southern subspecies (Eudyptes chrysocome chrysocome), which is the one I’m studying, breeds on the coasts of southern South America and the Falkland Islands.

study site

Staten Island, east of the Tierra del Fuego, holds two of the three known breeding colonies of southern Rockhopper penguins for Argentina, representing about 27% of the breeding population. This is an uninhabited island, except for two persons from the Argentinean Navy who are relieved every 45 days.

Staten Island

research

The objective of my research is to examine the predator- prey relationship during the chick-rearing period and determine if there’s any relationship between predation rate and subcolony size. Also, the activities of various predator and scavenger species that affect these subcolonies will be documented and quantified for the first time.

The predator/scavenger community at Staten Island includes Andean Condors (Vultur gryphus), Crested Caracaras (Polyborus plancus), Striated Caracaras (Phalocoboenus australis), American Kestrels (Falco sparverius), Peregrine Falcons (Falcos peregrinus anatum), Turkey Vultures (Cathartes aura), Kelp Gulls (Larus dominicanus) and Chilean Skuas (Catharacta chilensis), among others. Based on last year's observations at these subcolonies, the most common predator is the Striated Caracara…

Field work takes place during December, when chicks have already hatched. A ship takes us out to the island, we stay at “The Tents Inn”, and the field work involves daily observations at penguin subcolonies of different sizes. We record predator species that show up, their activities, and weather conditions.