point-to-point selection tool is ideal for this. maybe you're have to refine it a little with the tool set to addition or subtraction mode, or maybe you won't even have to do that. easy-peasy.
So I want to make this owl look like it's melting into an abstract, swirly pastel brick wall. I'm already cool on the wall designing, but how do I isolate the bird without it looking like it's blue-screened in a 1989 movie? Lasso can't be the answer, can it?!