pound.js

var fields = "W........WW.";
fields    += ".WWW.....WWW";
fields    += "....WW...WW.";
fields    += ".........WW.";
fields    += ".........W..";
fields    += "..W......W..";
fields    += ".W.W.....WW.";
fields    += "W.W.W.....W.";
fields    += ".W.W......W.";
fields    += "..W.......W.";
var width  = 12;

fields = fields.split(new RegExp(""));

var walk = function(i){
    fields[i] = ".";
    $.each([i-width-1,i-width,i-width+1,i-1,i+1,i+width-1,i+width,i+width+1],function(n,m){
        if("W"===fields[m]){walk(m);};
    });
};

var count = 0;
$.each(fields,function(n,m){
    if("W"===fields[n]){walk(n);count++;};
});

console.log(count);