Why do male animals sometimes guard females after mating?

In zoology, male animals often engage in mate-guarding behavior as a strategy to maximize their paternity when females mate with multiple partners over a short period. This phenomenon is driven by sperm competition, where the sperm of different males may compete to fertilize a female's eggs.12

By remaining near a female after mating, a male attempts to prevent other males from copulating with her before she can lay her eggs. This behavior serves as a form of paternity protection, ensuring that the male's own sperm has the highest probability of fertilization.12

Examples of these strategies include:
* Physical guarding: In species like the cobalt milkweed beetle, males ride on the female's back for hours to deter rivals.12
* Sperm removal: Damselflies and dragonflies use specialized genitalia to remove or compact the sperm of previous mates before depositing their own.12
* Cloacal stimulation: In dunnocks, males may stimulate the female to eject the sperm of prior mates.12
* Proximity maintenance: In groups of acorn woodpeckers, males stay within a few meters of fertile females to guard them from other breeding males.12