Pintura eggs only hatch if they are laid in another squid's ink. The ink needs to surround the egg to block out major sources of light (like the sun). Too much sunlight can cause the growing creature inside to perish.
Pinturas are the greatest enemies of pirate and their ships alike. Pinturas, diabolically, often let pirate ships pass their waters to allow them to carry out their treacherous acts of thievery. Then, when pirates are departing and are fully loaded with loot, Pinturas attack to steal the treasure and gold on these ships for themselves. They often attack ships in groups and surround them. Pinturas with the longest tentacles will wrap themselves completely around the ship from its main deck to the bottommost part of the hull that sits in the water.
This is why Pinturas are fearfully called "ship snappers."