Cushman & Wakefield (shown: its NYC HQ) and DTZ’s $2B merger—which created one of the world’s largest commercial brokerages—has led to some eyebrow-raising departures. Two DTZ executives—SVPs Jeffrey Donnelly and Ulrike Ahrens—are leaving for Colliers International only a week after the merger was finalized. Jeffrey, who's overseen DTZ’s real estate banking group since 2011, joins Colliers’ New York office as new executive director, with Ulrike serving as director. Cushman & Wakefield New York Tri-State Region president Ron Lo Russo will step in to lead the new C&W/DTZ New York office—which will now employ 43,000 people, including staff from DTZ’s Cassidy Turley acquisition. The two execs appear to be casualties of the merger, something that also occurred after DTZ’s acquisition of Cassidy Turley. All in all, 45 Cassidy Turley employees found themselves seeking greener pastures quickly after the acquisition, and we’ll just have to see if as many will be leaving from the new C&W. [TRD]