Groton — When Cmdr. Lisa Mack took command of the Coast Guard International Ice Patrol in 2010, both the Ice Patrol and the Canadian Ice Service were issuing similar warnings to mariners during the iceberg season.

The two services’ planes sometimes flew over the same areas in search of icebergs.

Mack said she has worked with her counterparts in Canada over the past three years to reduce these redundancies and use their resources more effectively, to ultimately deliver a better product to the maritime community.

The IIP and the CIS began issuing a joint iceberg chart in 2011 and made a concerted effort the following year to coordinate their patrols. They now have a joint reconnaissance strategy.

On Thursday, Mack turned over command of the New London-based unit in a ceremony at the University of Connecticut’s Avery Point campus to Cmdr. Gabrielle McGrath, a former deputy commander of the Ice Patrol. The Ice Patrol was based at the campus before it moved to Fort Trumbull.

Rear Adm. Daniel Abel, commander of the Coast Guard First District in Boston, presided over the ceremony.

In her speech, Mack, who was the first female commanding officer of the unit, thanked the many people who have supported the unit during her tour, including those who helped the Ice Patrol commemorate the centennial anniversary of the sinking of the RMS Titanic. The IIP was formed after the Titanic struck an iceberg and sank in the North Atlantic on April 15, 1912.

Mack said her time at the unit has been both challenging and rewarding.

“No commander of the Ice Patrol has a tenure long enough to accomplish what we have collectively accomplished in the last decade within the North American Ice Service,” Mack said in her remarks. “I commend my predecessors for taking the consecutive steps that enabled us to do the work we did over the last three years. And I encourage my successor to continue that long arc of international partnership in the best service of the maritime community.”

The Ice Patrol monitors iceberg danger near the Grand Banks of Newfoundland and provides the limit of all known ice to mariners to eliminate the risk of iceberg collision. There has not been a reported loss of life or property from striking an iceberg from ships that have heeded the warnings and steered clear of the area with icebergs.

The Canadian Ice Service patrols farther north. The North American Ice Service is an international partnership between the Ice Patrol, Canadian Ice Service and the Maryland-based U.S. National Ice Center.

McGrath said she plans to continue the partnerships that Mack has strengthened and look for other ways to do iceberg reconnaissance more efficiently.

McGrath joined the Ice Patrol in 2006 as the ice information officer and was promoted to deputy commander within a year, a post she held until July 2011. Most recently, she served as the assistant commandant of cadets at the Coast Guard Academy. McGrath graduated from the academy in 1996.

She said she was excited to return to the Ice Patrol, a family-oriented, small unit of 16 people.

“It’s like coming home,” McGrath said.

Mack is moving to Seattle to be the program manager for a maritime force protection unit.

j.mcdermott@theday.com