Couldn't find a reference to this but am sure you are correct.
ECHL teams are allowed to have 21 players on their opening night rosters with 2 players placed in reserve for a total of 23.
MARINERS CAPTAINS NAMED FOR 2019-20 SEASON - Maine Mariners
The current Mariner website still lists 25 players so we should soon hear of 2 more cuts and the two players on reserve, one of whom apparently is Ronning.
Maine has an affiliation with the Rangers/Wolfpack but also a secondary affiliation with Laval, the Montreal AHL team.
The 25 man roster breaks down as follows:
Rangers contracts (4) -- Crawley, Leedahl, Elmer, Ronning
Wolfpack contracts (6) -- McCollum, Tolkinen (Mariners Captain), McBride, Chase, Dmowski, Zerter-Gossage
Laval contracts (2) -- Lacouvee (goalie), Adams-Moison (forward)
Milwaukee contract (1) -- Savage (defenseman) alternate captain He played for Maine, which has his ECHL rights. He signed with Milwaukee but did not make the team and was sent to the ECHL where Maine exercised its rights to place him on its roster
Maine (12) -- Brassard (G), Coughlin (D), Kile (F), Wallin (F) alternate captain, Camarrata (F), Ferrell (F) all of whom started on Hartford's training camp roster
-- Crevier-Morin (D) alternate captain, Silvestre (D), Adams-Moison (F), McNichols (F) all of whom started on Laval's training camp roster
-- Fox (F) who started on Hershey's training camp roster
-- Master (F) who started on Lehigh Valley's training camp roster.
Because Maine has so many players it has cut several it signed over the summer and traded rookie Brett Supinski to Idaho for future considerations. It also declined to take two other Laval players who were sent to the ECHL.
Maine Mariners hope to hit their stride in second season
This is much more than you will want to know about Maine. From a prospect point of view the players to focus on are the four Rangers players, the four Wolfpack non veteran players and perhaps Coughlin and Silvestre, who are rookie defensemen and Master who is a rookie forward. Everyone else has been in the ECHL before.
First game is tomorrow night.