Post-copulation mate guarding in the sexually cannibalistic St Andrew's Cross spider (Araneae Araneidae)

In the field, only around 60% of male St Andrew's Cross spiders survive their first mating, with many of the surviving individuals losing their legs while attempting to escape from a female. Surprisingly, 67% of males that survive by leaping off the female's web return almost immediately to her web where they remain for several hours. However, males did not remate with the female. Laboratory experiments revealed that males remaining on the web can prevent females from remating with rival males entering the web. In the absence of a male, 75% of females remated with a second male, while only 47% of the females were able to remate with the second male if the first male was present. The guarding male engages rivals in physical contests, and even if the female remates, the presence of the guarding male reduces the duration of copulation.