Doubles and More Doubles

2011 has been a different kind of year with respect to juveniles. I am seeing more twin packs than I'm used to. The House Finches have at least two fledglings. And I spotted two juvenile Cardinals at the bird bath today. And yesterday (as seen in the photo) the Robins are taking care of two youngsters as well. In other words, half of the species I've seen with young birds this season have twins. So what can we conclude? relatively few predators? better food? less disease? All of the above? Whatever the case we simply have a year when the populations are sneaking a little higher. It's perfectly normal, statistically probable, and unlikely to be repeated every year.