Abundance and Distribution of Macaroni Penguins in the Antarctic Peninsula Flashcards
Guest Lecturer: Madeline Hallet
Where do Macaroni Penguins breed?
Sub-Antarctic island in Southern Ocean
What do Macaroni Penguins primarily feed on?
Krill
what is the estimated global population of Macaroni Penguins (as of 2013)
- 6.3 million breeding pairs
- 30% decline
Where is most research on Macaroni Penguins conducted?
- South Georgia Island
- Large concentration of Macaroni Penguins
What are possible reasons for the decline in the Macaroni Penguin populations on the South Georgia Island between 1980 and 2000?
- Decline in Antarctic Krill
- Competition with Antarctic fur seals
Antarctic Convergence
Marine belt encircling Antarctica that varies in latitude seasonally (cold Antarctic waters meet warmer sub-Antarctic waters)
What is the significance of the Antarctic Convergence?
It results in the upwelling of prey (high productivity)
What locations is breeding limited to for Macaroni Penguins in the Antarctic Peninsula region?
- South Shetland Islands
- Elephant Island
What were the objectives of the study?
- Estimate the total population of Macaroni Penguins in the Antarctic peninsula
- Identify local population changes
- Identify vagrant sightings
Vagrant
Non-breeding penguins sighted at locations where they have not previously been documented to breed
What causes vagrancy in birds?
Navigational errors in younger inexperienced birds
What methods were utilized to conduct the study?
- Added most recently available counts at all known breeding colonies
- Calculated % change in oldest available counts and most recent counts at individual colonies
- Documented and listed vagrant sightings for the region
How many breeding pairs were estimated based off of the 1993 census?
8,053 Pairs
Where did the majority of Macaroni Penguins breed?
Elephant Island
How many breeding pairs were located on South Shetland Island?
7 Pairs
How many breeding pairs were located on South Orkney Island?
22 Pairs
What is the predicted behavior of Macaroni Penguins based off of the study?
Southward expansion
What can happen as a result of changes in species distribution?
Increased infraspecific competition (for resources and space)
What is a beneficial adaptation that can help Macaroni Penguins in times when food is scarce?
They can prey switch if krill is low (this could potentially make them more resilient to climate change)
What are the conclusions of the study?
- Accuracy of the estimates are limited due to a lack of updated census data
- Need increased understanding of Macaroni Penguin demography and movement to make better predictions about the range of shifts under climate change
- Macaroni Penguin colonies may be capable of expanding to the South Pole as the Antarctic gets warmer
