Their closest relatives are the greenfinches, crossbills and redpolls. The first survey of Scottish crossbills was in 2008 . Birds include chickadees, kinglets, woodpeckers, jays, brown creepers, and red crossbills. The adult male is also a somewhat brighter (pinker) red than other male crossbills. Occasionally when red crossbills forage, there will be overlap between different call types. This species forms flocks outside the breeding season, often mixed with other crossbills. It will form flocks outside the breeding season, often mixed with other crossbills. This species will form flocks outside the breeding season, often mixed with other crossbills. It is slightly larger than other crossbills, measuring long and spanning across the wings. Birds present include red crossbills, Steller's jays, common ravens and many others. Between 2001 and 2006, less than 1% of Cassia crossbills paired with other call types. Farther inland, orange-crowned warblers, white-winged crossbills and red crossbills have been reported. Crossbills are said to peck the seeds out. It is believed that crossbills used the public information of different calls to forage. In future years, Scottish crossbills could suffer from the effects of global warming.