Gathering Paw Paws: Man vs Animal

Since we have an expert on paw paws, it seems the perfect time to bring up a problem I've been having the last few years. Renting where I do, there's no chance of growing my own paw paws. Thankfully, there's a healthy wild population locally and I know of two groves old enough to be productive. The problem is that these are public land, so I can't net or otherwise protect the fruits. As soon as the fruit even thinks of getting close to ripe, local animals pull them down and feast. Even if I am very careful to get out regularly, I only find them still green or the aftermath of an animal enjoying the bounty.

Can anyone think of something to resolve this? I considered trying to harvest a few green, but I have no idea if they ripen properly off of the plant and it seems like a waste if I go gathering a bunch of green paw paws only to have them stay under ripe tasting or rot without ripening at all. Is it possible to harvest them green without giving up the wonderful nature of a fruit ripened on the plant? It's been an exercise in frustration the last few years since the grove I used to find them at got sold and plowed down for a subdivision.

Did another check for the year, but looks like all hope is lost for 2019 harvest here. Everything is picked fully clean now where I am. They didn't even leave scraps this time. Still, I would like to at least know if I can gather unripe so I am ready for next year.