See, it's not Europe's responsibility to see to the safety and welfare of foreigners attempting to come to Europe, particularly when they're doing so in boats which are loaded far beyond their capacity. Karl Denninger has an example, eight hundred people aboard a 65-foot vessel--there's no way in hell a boat that size can safely carry eight hundred people.
Here's the thing: no nation (or bloc thereof) can support unlimited immigration. Allowing anyone in who can manage to safely arrive within your borders is a sure route to economic suicide, because those people will not come with anything and you will have to support them while they get on their feet...if they bother.
If they don't bother, they'll sponge off your welfare system ad infinitum. Regardless, they represent a drain on your economy, and it takes decades for refugee populations to produce more than they consume.
The situation presents any government with a moral quandary, and the only real way to keep this kind of thing from happening is to make sure it's known throughout the world that if you come here, you will be sent back. You establish channels for immigration and you also make sure that people know they can apply for an immigrant visa at any of your consulates, but if they don't have that visa when they come, they get sent back immediately.
The only good way to keep migrants from drowning in perilously overloaded boats is to makre sure they understand there is no point in getting into that boat in the first place. Is that heartless? It can be. Is it draconion? Perhaps. But if you're worried about people from third world countries dying by the thousands in the middle of the ocean, there's not much else you can do.