Your gooseberry bush, along with many other plants, is very sensitive during the pollination process, and heavy rain, strong wind, high temperature, and/or humidity can greatly impede the pollination process. Also, while gooseberries are self-fertile, planting a second variety close by will improve your yield.
Birds won’t eat them until they are fully developed, so that’s not a likely cause of your problem.
Does the bush get direct sunlight all day long – or is it shaded a good part of the day? This is a common problem that people often don’t recognize. Fruiting plants need lots of direct sunlight to produce fruit. If this is the problem, wait until October and transplant your bush in full sun.
What are you feeding your plant? Without proper nutrition it will not set fruit. This is another very common mistake people make in trying to grow fruiting plants. Trees grow so slowly that they can wait for the natural chemical processes constantly going on in the soil to provide water-soluble minerals, and thus don’t need much supplemental feeding. However, vegetables and small shrubs can’t wait! They grow fast and require supplements of water-soluble minerals for optimum health and fruit production. Go to the Gardening Techniques section under Fertilizers, and either mix your own natural mineral nutrients or order some pre-mixed from The Store section.