The melon is aborting, not uncommon at the beginning of the season when vines are not established enough to support fruit or the flower failed to get pollinated. Usually exhibits as blossom end rot Mechanical damage to fruit can also cause it.

From the pic it appears that the vine is elevated along a fence line? Those 2 dark marks look like a top & bottom beak bite possibly from a bird which landed on the fence? Just guessing here of course. It also appears that the attached blossom has not bloomed yet and is still at it's pre-open stage.

I did figure out that birds are trying to ear my mwlons need ro refull the bird feeders!

If that melon survives it may have a birthmark /tattoo, let us know how it turns out.