Try taking out small ads in next year's fishing/hunting regulations guides for the states in your area.

Contact some of the state wild life agencies and get on their email lists.
1. It will help you provide valuable content to your members
2. You might find a wildlife employee or two willing to post on your site. I have a guy on my site who interacts with the users and provides great info. And, it adds credibility to your site.

Finally, you might want to consider simplifying your name to just "Northwest Outdoors"

I've been slowly growing my site since 2001.

Sometimes slow is best. Never ever stoop to posting on other similar forums to draw attention to yours (unless you get permission first.)