Unknown balcony sprouts

I planted these guys a week ago and just a couple of days later they started sprouting. I foolishly didn't mark the box with what seeds I'd planted, so I don't really know what these are. After buying brand new boxes, I planted basil, cilantro, early jalapenos, tomatoes, dill, mild & spicy lettuces, radishes and baby brassica greens, all from Urban Harvest seed packets. I think these might be the radishes or the brassica greens.

Oh, and see the spikes? That is what I have to do now to keep the pigeons from nesting in my plant boxes. After 2 nests and two yucky clean ups, I'm pretty much done with baby pigeons, so my boxes are spiked with bamboo skewers.