Protecting migratory animals is challenging because males and females can travel to different places at different times of the year. In this study, Dr. Ginger Rebstock and Dr. Dee Boersma tracked male and female Magellanic penguins during their migration and found that females stayed closer to shore and slightly farther north than males. Both sexes reached similar overall latitudes, but some males started traveling south by June while females generally did not. Because females stayed closer to shore, Rebstock and Boersma theorize that female Magellanic penguins are more likely to be harmed by fishing equipment and pollution than male Magellanic penguins.
Authors: Dr. Ginger Rebstock and Dr. P Dee Boersma
Journal: Marine Ecology Press Series
DOI: 10.3354/meps14476
Summary
Written by Sofia Denkovski
Protecting Migratory Species
- Migratory species often show spatial/temporal segregation of sexes, which can lead to sex-biased mortalities.
- Sea-birds commonly exhibit sexual segregation in migration, winter, and sex-biased mortality. Magellanic penguin females have higher mortality than males in winter.
- To protect these species, an understanding of distributions of the sexes is essential.
Sexual Segregation of Magellanic Penguins
- Females stayed approx. 47 km closer to shore than males.
- Females were found in northern areas more than males.
- Females departed the colony earlier than males.
- Mates did not overlap at sea.
Effects of sex-biased distribution on females
- Increased likelihood of gill-net entanglements and beach strandings.
- Increased effects from pollutants in the Rio de la Plata river plume.
- Northern foraging areas are utilized by various marine mammals, sea turtles, sea birds, etc.
What does this tell us?
- Northern and near-shore distribution of females increases their vulnerability to pollution, entanglement, and harmful algal blooms
- Further protection of female non-breeding and migration areas is essential!
