In spring, Tricolored Blackbirds stage one of California’s great birding spectacles, amassing in the tens of thousands to breed in the Central Valley. This season, the largest colony documented so far is in Merced County, with a preliminary estimate of 29,000 birds. Like many bird species, these charismatic blackbirds are extensively studied and monitored during the breeding season — after all, this is when they are most apparent across the landscape. Less is known about their lives during the rest of the year, when they disperse across the state and mingle with their more common cousins, like the Red-winged Blackbird. Insights from full annual-cycle tracking can expand our understanding and help guide conservation decision-making. Protecting Colonies Takes Collaboration and Careful Timing During the breeding season, we find tricolored blackbirds nesting in an array of habitats — upland grasslands, wetlands, and fallow fields.…