Invest in a bigger SD card. We have an 8GB one which holds roughly 2000 images (as long as you’re not shooting in raw). Lasts us many a trip as long as we copy everything to the laptop at the end of the night.
I have 30gb card. I do shoot in raw because I like fooling around in Lightroom. I’ve had the camera for 6 weeks and already my pictures folder (including lightroom files) is 101gb.