So yes, I guess those animals were pretty unlucky to be eaten by wandering predators and scavengers, but maybe that's actually luckier than dying of hunger and thirst.
However, it faces many challenges on its terrestrial journey: it's now in danger of suffocating, drying up, suffering physical damage from rough terrain, and being hunted by land predators.
Many creatures use light generated within their bodies to attract a mate, or even prey, or to camouflage themselves against being a silhouette from predators below by faintly lighting the undersides of their bodies.