Tools for Birding
Ok, now that you've got some feeders up, what next? Unless your feeders are located right next to your watching post, you will want a pair of binoculars. We recommend a decent pair of 7x42 or 7x50, or maybe 10x50 if you can be still. The first number is the power. 7 to 8 is about the highest most people can handhold without too much shaking, although some people are comfortable at 10. Anything higher will require some kind of mount. The second number is the diameter of the main lens. The bigger it is the better performance will be under low light conditions, but the heavier the binoculars will be. We have been happy with a pair of $40 7x50 Bushnell binoculars, but a word of warning: if you ever look through high quality optics, you'll never want to go back. Jan got a pair of Wind River 10x42 Roof Prism Binoculars for Christmas a while back. You can tell the difference, but they cost $300 more than the Bushnells! We will try to find some good info pages, and put links here.
Next, what the heck are you looking at? You want at least one book, preferably more with different pictures. We prefer books with actual photographs as opposed to drawings, and our favorite is the Stokes Field Guide to Birds, Eastern Region (ISBN 0-316-81809-7). We also like the Audubon Society Field Guide to North American Birds (ISBN 0-394-41405-5), and An Audubon Handbook: Eastern Birds (ISBN 0-07-019976-0). Stokes also has a series of books about Bird Behavior which we found interesting.
Spotting Scope
If you have a small backyard and never go birding in the field, you probably don't need a spotting scope. A spotting scope will give you more power and light at the expense of weight, it will require some kind of tripod or other mount, and it is one more piece of gear to keep track of. However, if you get into birding seriously, you will probably want one. Again, quality optics cost. Also, you need a quality mount, which will add to the cost, and the weight.
Pat: "So why am I so down on spotting scopes? Because I want a Questar!" At last check, Questars are going for about $4K. Thats pretty hard to justify. So we don't need one. We don't...
If you REALLY get into birding, you are probably going to want to try your hand at photographing birds. We are just now at that point. We'll let you know how it goes, but we imagine we will be shelling out a few bucks for at least one or two long lenses for the Pentax.