I can't find Boars!

Solution 1:

The reason you aren't finding any boars is because there are very few areas where they are common. For example I've unlocked 8 Radio Towers and have only opened up one area that has them.

Here is the the best screenshot I could take that should allow you to figure out how to get to the boars. Also pointed out what a pig is so you know the difference.

^{Click on image below to view the larger, original size image.}

also here is a close up of a boar and pig

Solution 2:

Where can I find boars not too far from the starting zone?

As mentioned by PhysicalEd in the comments, there are boars just north of Dr Earnhardt's mansion.
If you use the ziplines near the mansion you'll see them.
In fact, you'll probably see them during the "Mushrooms in the Deep" story mission.

There are 4 boars there. They do not respawn, but you will have enough boar hides after skinning them (assuming you didn't sell or discard any of them):

• During the "Harvest the Jungle" story mission, you have to skin 2 boars, and then use both hides to craft the "Simple Rucksack".
• You also need 2 boar hides to craft the "Simple Ammo Pouch"
• Finally, you need 2 boar hides to craft the "Rugged Fuel Sling"

As for the difference between the boar symbol and the pig symbol on the map, basically the pig is the one that looks to the right, while the boar looks to the left.