How do Mascots Come Up with their Costumes?

You've been there with one sports enthusiast or another. Its mind blowing how they know all the teams in all the professional leagues for each city across the country. We're not talking about just the big ones: NFL, NBA, MLB. Once you start including the lesser known professional soccer teams, hockey, lacrosse, and even women's pro basketball teams, this really gets complicated. There are identifying team colors, team names, and finally the team mascot. Hundreds of different mascot costumes identify professional teams across America. It is an irreplaceable way to bring interaction between the field, court, or ice, and the fans in the seats.
So can there really be that many different animals to represent these teams? In the NFL, the Philadelphia Eagles have a character roaming the sidelines; of course, it is a dress up of an eagle, in team colors. Other given mascots like this include the Toronto Raptors' Raptor (NBA), Baltimore Orioles' black and orange bird, Minnesota Lynx's cat mascot named Prowl, and the Calgary Roughnecks' Derrick is a mascot costume of a man in jeans and the team's jersey, high boots, a hardhat and workgloves.
How many tiger mascots can you think of? Well first to my mind is the cartoon rep for Frosted Flakes, but that's cheering for a cold cereal instead of a sports team. With the Cincinnati Bengals, Detroit Tigers, and universities and colleges in Auburn, Colorado, Idaho, Florida, Louisiana, Missouri, Texas, Tennessee, and New York, tiger mascots are one of the most popular mascot costumes.
It is fun to see how some teams come up with their mascots when there seems to be little connection. When your team name is the Canucks, Real, Rockies or Nuggets, there's room to have a lot of creativity in making the mascot costumes. That's just what these teams have done, and they have come up with original mascot costumes that the fans love, and that sports enthusiasts recognize across the country.
Starting in Canada, the Vancouver Canucks is a team in the NHL. Generally, a Canuck is a person from Canada. How were they going to put that into a mascot? I doubt it would have been as easy as the above Roughneck, Derrick. In Fin is a 6'3 killer whale that beats his drum through hockey games, and how many mascot costumes do you know that blow steam through a blowhole?
Major League Soccer is the national professional soccer league. A new team in Salt Lake goes by Real. When it came for a mascot, they chose fearless lion mascot costumes and named the official mascot Leonardo. There are no lions in Salt Lake, or even in the United States, but maybe they are saying that as the king of the jungle, they are king of the soccer field. Just my guess.
A classic team in the West, the Denver Rockies baseball team has a loyal fan base. Dinger, the giant purple dinosaur can be spotted waddling around the stadium and on the roofs of the dugouts. He doesn't get involved on the field as much as he does with families in the stands and refuses to claim relation to Barney.
Also in Colorado, the Denver Nuggets sponsor Rocky. Not related to a golden nugget except in color, Rocky is a cougar or mountain lion of some sort with a lightning bolt tail. Arguably one of the best mascots for being athletic and involved through the basketball game. He plays games, does flips and dunk tricks, taunts the refs, rides motorcycles, and gets the audience pumped up to cheer for their team.