Forget about the early bird getting the worm. It's your strawberry patch he's after!
Birds have an uncanny knack of finding the red, ripe berries before you do. See, the green one is untouched. But unlike tomatoes, strawberries must ripen on the vine and cannot be picked when green.
The best thing to do is to cover your patch with some sort breathable material that lets in light and water, but keeps birds out. Commercial products, called floating row covers, are available for this purpose. You can find many options online, including this one:
Most of the commercial row covers are sold in long lengths -- the shortest I found was 6 by 20 feet.
If yours is a small patch, or if you'd just like to try some do-it-yourself options, read on:
I made two kinds of strawberry nets, one with cheesecloth and another with tulle that I had left over from some party decorations.
I bought the cotton cheesecloth at the grocery store for $3. I imagine that dimensions vary with the packager, but my piece measured 3 by 6 feet. I gently draped it over my several plants, anchoring it to the ground on the edges with rocks or bricks. Mosquito netting, available at some discount stores, would also work great.
You can put a tall, heavy object in the middle of your patch, such as a cinder block on end, if you wish to keep the cloth from touching the plants.
The tulle I had is only 6 inches wide. I used it more as a protective "scarf" than an overhead net. I wrapped it a couple of times around the cluster of green berries and blossoms, but did not cover the leaves.
Truth be told, this method arose out of necessity, because my piece of cheesecloth wasn't big enough to reach a few straggler plants. Yet, I think that it can have an added benefit of keeping the berries off the ground (where they are more susceptible to rot), since you can wrap them from all sides and make a little hammock. This method is also less conspicuous than a large net or row cover.
More thoughts about strawberries: There are basically two types, June-bearing and everbearing. Whichever type, to encourage strong plants the first season you plant them, pluck off blossoms before they form berries. (I know that's hard!) You want the plant's energy to initially go into strong roots and structure rather than in producing fruit.
Soon, strawberries will shoot out runners like crazy. This is a fun way to grow more plants, but at the cost of fruit production. Decide which you want right away: bigger strawberries and more of them, or more plants.
If you keep runners you can guide them where you want. even burying them a bit to help them form roots sooner. When your alloted patch is already bursting with plants, but you want more elsewhere, try this trick: Put a dirt-filled pot right in the patch and nest a strawberry runner there. (You may need to use a J-shaped piece of wire to hold the runner in the pot.) After a week or so, check to see if the baby plant is firmly rooted in your pot. When it is you can cut the runner from the mother plant.