How can an albatross stay airborne for months?
I'm not really inside the field but few weeks ago I noticed a Plos One article that was dealing with this. Indeed albatross can fly for thousands of miles and this is possible at no mechanical cost, because they use a dynamic way of flight that takes the energy from wind (dynamic soaring) (ref-1). Their muscle-skeletal system further evolved so that no energy is required to keep open the wing.

In addition, when foraging, they minimize diving and landing activities because they follow Killer Whales, so that food is always in proximity. (ref-2) Very smart birds.

ref-1 Sachs et al., Plos One 2012

ref-2 Sakamato et al., Plos One 2009 both references are open access.