I’ve fished all my life in a rather unique area: South Florida, Biscayne Bay, The Gulfstream, the Florida Keys, Florida Bay and the Gulf of Mexico; and have always done better at first light, the first couple of hours of daylight, and again at last light, dusk. I somehow got the idea that this is because most fish (except for nocturnal ones, that are active, night feeders) are able to see their prey again in the early morning after a long night. Then again, at last light, they are eager to get as much food as they can before the long night, poorer visibility ahead. Also, especially in my subtropical environment, the heat is a factor. Cooler early in the morning, hotter as the day progresses, cools down at dusk.
I’m also a lifetime birdwatcher/audubon, and spend a great deal of time in woodland, wilderness settings, and the same generally holds true here; in fact, nearly all wildlife is more active, plentiful in early morning and again at dusk. I assume this is for the same reasons…can see their prey better again (early morning), and want to get that “last meal before darkness sets in” (dusk). Again, the exceptions are nocturnal creatures, for example owls. Hope this makes sense to you. Between your choices, I would definitely choose 8am-12pm, even try to get out there earlier.
I just noticed that this question was asked two years ago! LOL New to fluther.