On my Nikon D3000, continuous shooting doesn't always work,,

[Calendula]

It's been a year now since I purchased the Nikon D 3000 18-70mm plus the accompanieng Nikkor 300mm lense and I am really pleased with the camera's performance. I also like to mention that I was told by my family and by my friends that I really caught on to this unit a lot faster then they thought I would. However, right from the start I noticed something that concerned me which has to do with multiple shots. I have been taken a vast number of bird pictures since last year and like to take my photography one step further now in that I like to take the bird in flight, or it's flapping its wings, etc.
Today, upon driving down to the lake I spotted a couple of Geese and I used my continuous shooting on my camera quiet often, even though the Geese did only move slowly. The reason for that was because I wanted to be ready when the birds took off in flight. When they did take off and I pressed the shutter button but it would not release any pictures, it did not do anything. I think I read here somewhere before that you have to wait a while after you take a few pictures in continuous shooting because the battery gets low and run down and has to re-charge itself again first before you can go ahead with more shooting. Is this so?
Did anyone here have the same problem? could it be that this is the way the camera works . or is it me doing something wrong? I like to hear about it from you if I could please. Thank you in advance.

[rjseeney]

It's not related to the battery, but to the buffer. The camera will slow down as it is writing the images to the card. Entry level cameras tend to have smaller slower buffers.