Hi Al, Thanks for the comment.  I have reviewed your thoughts and decided to respond.

•  My reaction to your first question: (excerpt: "what does justify killing of wildlife?") You are on to something when you say "survival" may be a reason for killing wildlife. 
• You go on to say that survival or subsistance hunting is  "obviously not an issue in our country", but some people might disagree, especially during this economic downturn.  Unfortunately for animals and wildlife, as of July 2011 there were 311,591,917 people in the United States (census Bureau), and according to the world clock, there were 7,003,026,301 (and counting as of 03/26/12 20:47) in the world.  The answer gets more complicated when you consider "prey" animals versus "predators".  We have killed many of the predators and have actually encouraged the populations of animals we hunt.  Now we (I use "we", as a label for us as culture, but I acknowledge that our culture may be changing, albeit slowly) look at predators as competitors.  According to Cornell University, Wildlife Control Information page, there are approximately 20 million deer in the US, a 15.5 humans to 1 deer ratio.  
• Again this issue becomes more complicated when I consider poaching.  In a part of the McKenzie River watershed in Oregon the deer and elk population was recently decimated by a poaching ring.  Although the area is off limits to legal hunting since the discovery of the poaching, these animals are seldom seen, now. You are right about it being more of an issue in other countries where as population grows, more wildlife is killed to make room for people and to feed people. 
• I realize this is a bit rambly.  As I wrote, I became increasingly aware of how complicated these issues are.  I did come up with one answer: Killing of wildlife might be justified for self defense. 

I appreciate your thoughtful comments on my first blog.  I hope you continue to respond and I will continue to repond as well as present new blog thoughts.  I also invite others to join in the conversation.  Just click on "Leave Comment"  or "# Comment". Usually one or the other will be highlighted.