Help needed, birding with a D5000.

I am not sure your first pic is in focus. With a long lens its easy to miss focus sometimes. Stabilization goes a long way with longer focal lengths. I have recently started using a nikon 55-300mm vr with my d5000 and I was initially surprised that at 1/50 to 1/100 I am not getting sharp pictures as I was getting with the kit 18-55 mm lens. Then I remembered reading something about the shutter speed being atleast equal to 1/focal length. Now with the shutter speed in the vicinity of 1/300 pictures are really sharp. VR really does work, esp the newer version, VRII that is built into this lens. At the long end of the zoom, sometimes 1/300 will be too fast for evening light or overcast day. VR comes in handy at this time.

The nikon 55-300 vr is not very fast at AF, but its cheap and within ur budget. I bought it from Adorama for 209$ refurbished.

Search for nikon refurbished on Adorama, they still have the deal, and a even cheaper open box item.