In this photograph an adult male northern elephant seal (Mirounga angustirostris) mates with a much smaller female. Note that the female is not given much choice in the matter. This is quite typical in elephant seal society, somewhat akin to human society of a few million years ago. The female’s pup is seen just in front of her, and stands a reasonable chance of being overrun by the event.
A bull elephant seal forceably mates (copulates) with a much smaller female, often biting her into submission and using his weight to keep her from fleeing. Males may up to 5000 lbs, triple the size of females. Sandy beach rookery, winter, Central California.
Image ID: 20388
Species: Elephant seal, Mirounga angustirostris
Location: Piedras Blancas, San Simeon, California, USA
Also, see this photo of rough sex among otters.