This video from South Georgia is called King Penguins and Fur Seals at the beach.
From PLoS ONE:
Mass Mortality of Adult Male Subantarctic Fur Seals: Are Alien Mice the Culprits?
P. J. Nico de Bruyn, Armanda D. S. Bastos, Candice Eadie, Cheryl A. Tosh, Marthán N. Bester
Mammal Research Institute, Department of Zoology & Entomology, University of Pretoria, Pretoria, South Africa
Mass mortalities of marine mammals due to infectious agents are increasingly reported. However, in contrast to previous die-offs, which were indiscriminate with respect to sex and age, here we report a land-based mass mortality of Subantarctic fur seals with apparent exclusivity to adult males. An infectious agent with a male-predilection is the most plausible explanation for this die-off. Although pathogens with gender-biased transmission and pathologies are unusual, rodents are known sources of male-biased infectious agents and the invasive Mus musculus house mouse, occurs in seal rookeries.
Methodology/ Principal Findings
Molecular screening for male-biased pathogens in this potential rodent reservoir host revealed the absence of Cardiovirus and Leptospirosis genomes in heart and kidney samples, respectively, but identified a novel Streptococcus species with 30% prevalence in mouse kidneys.
Inter-species transmission through environmental contamination with this novel bacterium, whose congenerics display male-bias and have links to infirmity in seals and terrestrial mammals (including humans), highlights the need to further evaluate disease risks posed by alien invasive mice to native species, on this and other islands.
Citation: de Bruyn PJN, Bastos ADS, Eadie C, Tosh CA, Bester MN (2008) Mass Mortality of Adult Male Subantarctic Fur Seals: Are Alien Mice the Culprits? PLoS ONE 3(11): e3757.
Evolution rampant: house mice on Madeira: here.
A study of the migration patterns and foraging strategies of Antarctic fur seals: here.
Hookworms exploit a live fast/die young strategy in their South American fur seal pup hosts, report Morris Animal Foundation-funded researchers at the University of Georgia. As a result, they often kill their host, rather than finding a happy equilibrium. Scientists are concerned that this type of hookworm infection could eventually pose a risk to critically endangered populations of fur seals: here.