Black-ray goby mother bird regurgitating food to her chicks. This way, the shrimp and the goby are kept well fed. Sometimes, if the shrimp is not kept well fed, it will resort to killing the goby. In the wild, most burrows are shared by male and female goby pairs, with their respective shrimp partners, and the female goby will use this burrow as a nesting site to lay her eggs. The obvious benefits to both organisms of this symbiotic relationship make the interaction a form of mutualism. Here is an interesting example of this. The other fish is a dartfish (genus "Ptereleotris").
Sphinx blenny mating, the blennies form distinct pairs, and the females lay up to 7000 eggs in a sitting, which are then guarded in burrows by the males. Males are known to cannibalize dead eggs to prevent infection spread amongst the healthy eggs, although in smaller broods they have also been reported consuming living eggs. It is believed that this is due to limited feeding opportunities for the males during breeding, as a result of their restriction to the nests. FishBase considers the blennies to be of Low Vulnerability, with a reproductive doubling time of less than 15 months. Sphinx blenny The