Hi Jared and COBirders, we've been seeing BIG numbers of overnighting gulls (perhaps up to 2,000) on Cooley Lake here at South Platte Park in Littleton for past 1-2 weeks. Flocks come in 4-5pm and then fly out 7-8 am in the morning. While Cooley Lake is not open for general public access, there has been pretty good spotting scope viewing into Cooley and of gull flocks from the Mineral Ave sidewalk, a 5-10 minute walk from the Carson Nature Center. Over a couple cold mornings we have picked out at least one Glaucous and 2 Lesser Black-Backed gulls, and could possibly well be others mixed in, birds were pretty hunkered down and packed together. Happy Birding!