I used to hunt there alot. Its SUPER thick! The floods of the early 90's really took its toll. The place is practically a maze of fallen trees. LOTS of deer there ! Best way to do it, is go over to Weldon Springs access, and cross the river by boat. That way, you'll be on the back side of the island, harder to get to, on foot. BE VERY CAREFUL CROSSING THE RIVER, there's tons of whirlpools swirling around, along with wing dikes to avoid.
The island is approx 2 miles wide, and 5 miles long. Crops used to be planted in the middle of the island, I guess they still do. That seemed to be a gathering spot for a lot of hunters.
try the back side of that island and make sure you have a compass/gps/cell phone but mostly all three because its really easy to get lost in there! there is some NICE bucks in there though if you have enuff patience but good luck!
Another way to do it is to go to the parking lot(thats the causeway) and put a canoe or small john boat in and head up the slough, theres almost no current. A friend of mine killed a giant buck back in there