They are fairly easy to tell apart from ant hills. The soil has clearly been pushed out in neat, and, assuming it hasn't rained, appears lose and flaky. The entrance is usually perfectly round depending on the size of the bee. They're also very likely found around one another in close proximity where as ant hills are not so much. Usually a diverse array of ants will inhabit such a hill side, each with their own sized entrance hole and mound configuration. Some eliminate the grass around the entrance while others leave it there for example. Also when it's an ant hill it's usually quite obvious from the ant traffic going in and out.
Here is a mound of Pavement ants, Tetramorium species E, for lack of a better species name. You can clearly see from the size of the grains and nest entrance it wasn't constructed by bees. This species is invasive and more than likely in your front lawn, so I didn't bother with a close up this time.
Panasonic Lumix DMC-ZS3 10.1 MP Digital Camera with 12x Wide Angle MEGA Optical Image Stabilized Zoom and 3 inch LCD (Black) I had a hard time finding this camera after I herd about it from Alex Wild. Target, Best Buy, and Walmart didn't have it! I ended up having to go to a specialty camera and technology store. The sales person was very good at talking me into buying all sorts of stuff for it. I'd say all you need is the camera, memory card, and a second battery. The only downfall so far is it saves Video as an MTS file. Can't just open that with quicktime. But it does comes with software for to upload those to youtube and such. It's a little confusing to use. But the macro is excellent for a camera that doesn't need special lenses.