Part cinematic tone poem, part portrait of society’s marginalized, part painful domestic drama and part Southern-fried hokum, Benh Zeitlin’s debut feature has to be admired for its ambition and its visual artistry. But it leaves a good deal to be desired in terms of coherence.

The “Southern Wild” of the title is a patch of swampy Louisiana coast that’s been totally cut off from the mainland by the levees constructed to protect New Orleans. The place, called the Bathtub, is home to a gaggle of free-living folk who set up trailers and hand-built structures as homes and live a simple pastoral existence, deliberately separated from the “civilized” world.

Among its denizens is Hushpuppy (Quvenzhane Wallis), a feisty six-year old girl who narrates the tale in a manner reminiscent of little Linda in “Days of Heaven.” She lives there with her father Wick (Dwight Henry), whose wife went off years earlier. He’s a tough, self-reliant fellow who loves his daughter but can also be very hard on her, because he’s trying to prepare her to survive without him. Wick is terminally ill, and knows that before long Hushpuppy will be on her own, so he’s set up her own place and orders her to stay in “her house.”

The coming loss of her father is equated with the community’s threatened loss of its home to flooding from the coming hurricane. With the levees holding the tides from encroaching on the mainland, the Bathtub will simply become uninhabitable, and “the authorities” will force the evacuation of everyone who lives there. This seismic change is symbolized in the arrival of a thundering herd of prehistoric aurochs, huge primeval boars that come trampling through the brush. Wink and some of his neighbors try to stave off disaster by attacking the levees in order to release the flood, but it’s to no avail: “rescue” workers remove those dwelling there to a mainland shelter, where Wink receives medical care. But the Bathtubbers refuse to be kept there; they stage an escape and return to their happily unstructured life.

That will involve a dreamlike experience for Hushpuppy, who, along with some others, will hitch a ride on a weirdly-constructed boat built atop an old truck chassis that takes them to a floating brothel-cum-crabshack which serves not only food but a sort of familial bond as unusual as their own.

“Beasts of the Southern Wild” tries to fashion a mythic tone, equating nature’s destructive wildness with the loss of parents and the encroachments of a modern world that squelches the possibility of a primitive, unfettered mode of life. It wants to link all these threads in the single persona of Hushpuppy, the strong, persistent child who’s their singular target.

And it must be admitted that in the uncanny work of young Wallis, it creates an indelible character, seconded well by Henry. Both are untrained first-time actors from whom Zeitlin draws wonderfully natural performances. The supporting players are less memorable, but the director and his crew employ the unusual locales to good effect, despite the obvious budgetary limitations. While one can respect what Zeitlin is trying to accomplish, however, he never manages to unite the various themes into a satisfying whole, and too often allows his drive for hallucinatory imagery to trump simple intelligibility

The result is reminiscent of another debut feature, David Gordon Green’s ruminative, bucolic “George Washington” (2000), which was similarly stronger on the visual than the narrative side. Of course Green has since gone the commercial route with such wretched stuff as the unspeakable “Your Highness.” One hopes that Zeitlin will choose to perfect the style he’s embraced here rather than selling out in like fashion.