Hydras produce more hydras through a process called budding. In budding, small hydras, complete with tentacles, grow on the side of a larger hydra and then break off to form new individuals. Hydras can, however, also reproduce sexually. Males produce sperm, which are released into the water near a female to fertilize her eggs. Fertilized eggs become embryos that attach to the side of the female. After the tentacles and mouth are developed, the newly formed hydras then separate from their mother and live independently. Hydras produced sexually are generally more resilient and have a better chance of surviving cold winters than those that developed through budding.