When fruit-bearing vegetables (tomatoes, peppers, corn, etc.) are ripe, that can attract many unwanted animals to the garden: rabbits, groundhogs, raccoons, squirrels, etc., eager to nibble on the fruit before you can save the harvest.
To help scare them off, try applying a handful or two of blood meal, actually a fertilizer, to the soil around the plants. This has to be done at just the right moment, only a few days before they reach maturity. The idea is to confuse fruit-eating varmints. The presence of blood could indicate that there are dangerous predators in the vicinity, causing them to stay away. Of course, mammals are quite intelligent and will eventually realize there is no danger, but with a little luck, you’ll have brought in the harvest by them.
What About Birds?
Note that blood meal will have no effect on fruit-loving birds: they tend to use their vision rather than their sense of smell to detect predators. If you fear birds will attack your crop, often the easiest solution is to cover them with protective netting, available in any garden center.