I'm taking a slightly different tack on this one. I think you should have let him restrain you, and waited for the Bernalillo County Sheriff to arrive. Despite the rantings of conspiracy theorists, most law enforcement folks are very adept at seeing the forest through the trees. Most likely he would have ended up in handcuffs, having threatened you. And you may have ended up with a citation for trespassing, if the Rio Grande Conservancy property is posted off-limits (which I can't recall if it is or not).

You also need to see the other side of the coin. For the edification of those reading this who are not aquainted with the provincialism of New Mexico, the Rio Grande valley through Albuquerque is rife with crime and gangs. And this is not a recent phenomenon; there've been hispanic gangs here for generations. Its possible this property owner has just had enough of constant vandalism and break-ins, and a non-responsive (or, more likely, over-worked) police force. Which doesn't justify his behaviour. But understanding this ahead of time may have given you some clues to help defuse the situation.

This story really isn't about photographer's rights. Its really about what happens to communities when crime is allowed to fester for generations.

~Joe in Albuquerque