In late September 2016, five oceanographic moorings were deployed in the eastern Hudson Bay and at the entrance to James Bay(Figure 1). These moorings were supposed to be recovered in summer 2017 during the BaySys cruise onboard CCGS Amundsenor White Diamond-a vessel refurnished in 2017 for the Churchill Marine Observatory. Later, a decision on turning the moorings from White Diamondinstead of recovery was made. Unfortunately, the slow progress of ship’s inspection from Transport Canada caused multiple delays of ship’s departure from Prince Edward Island and the 2017 cruise was cancelled. Because of the critical role of these mooringsfor the scientific objectives of oncoming Amundsencruise in spring 2018, the opportunistic cruise onboard CCGS Henry Larsenwas conducted in October 26 –November 1, 2017 in order to maintain the uninterrupted measurements. The goals for this short cruise were to retrieve and re-deploy as many BaySys moorings as possible accompanied with the concurrent CTD and water sampling.