Could this summer’s breakout film star be Mark Bittner, a graying San Francisco hippie with no girlfriend, no apparent means of income, and no abdominal six-pack? He’s a regular guy in every sense of the term, and perhaps even less estimable at first glance, certainly among the feisty young go-getters in his scenic bayfront neighborhood. His fledgling career as a musician foundered years ago; he was homeless for more than a decade and lived on the roof of a hotel. Yet he proves himself a hero in this mellow but entertaining and engaging documentary, which examines his relationship with a flock of wild parrots (one of two in the city, it turns out) that populate the trees around Bittner’s rent-free crash pad. Bittner spent a year getting the birds to come to him, and the film likewise takes its time. Over the course of its first two acts, we meet some of the 45 birds – a downtrodden and mateless blue-crowned conure, a pair of cherryheads, a banded former house pet that nibbles Bittner’s shoes. Just as she’s getting us comfortable, Irving draws the net with a sudden reversal of fortune: Red-tailed hawks are circling the flock, and Bittner’s otherwise infinitely patient landlords announce the renovation of his building. He’ll have to move, and the birds will be on their own. The film invites such an emotional investment in its subjects – human and avian alike – that there is a real sense of loss when Bittner packs up his hot plate and his Gary Snyder books; there is real, old-fashioned movie drama in the fate awaiting the birds. Thus the film reveals itself to be far more than an urban curiosity piece; its subject is compassion itself, the noblest of human possibilities. It asks difficult but worthwhile questions: How do people make their way in a world that is often intolerant of eccentrics and encourages conformity? What kind of relationship should human beings have with nature? (Irving gives time to the viewpoint that Bittner’s interference with the birds is not in their best interest, nor in the interest of native species.) And, interestingly, it depicts an average person’s journey into a world of dedicated scientific inquiry, which makes it a fine choice for all-ages viewing. Though Irving is a nature photographer and an environmentalist, she does not romanticize the birds unduly. We see them, for example, turn on the weak and injured of their own species. Rather, her background affords truly breathtaking close-ups of the animals and their environment, an urban haven of lush hillside foliage that encloses one of the city’s historical wooden staircases. Well-considered, beautifully made, and often gripping in its narrative, the film epitomizes the best the documentary format can offer.