Piping Plover lay a bunch of eggs, usually three or four, called a clutch. They pump out approximately one egg each day over four consecutive days.
The trick is to get them all to hatch at the same time a month later. To pull this off, they usually delay incubating the eggs as much as possible until the full clutch is in place. This is often pretty easy to do as PIPL lay their eggs in the spring when it is still generally cool down the shore. Cold eggs can chill, both literally and figuratively. Heat is the issue. They will cook quickly in the hot sand.
It appears Jack & Elizabeth botched this maneuver. Poor Davey Jones is going full rogue, all by-self, while Jack & Elizabeth are stuck tending to the other eggs which have yet to hatch. Perhaps it was just too hot when they laid the eggs. Perhaps they just don’t know what they are doing yet.
Sadly, this situation usually ends badly. Logistically it is going to be a nightmare for Jack & Liz to manage four little babies of varying ages and varying levels of rogue.
While lil’ Davey Jones might be a lil’ bored waiting for his sibs, he’s a lucky boy. Being first born he will have the best chance at surviving this dicey situation.