There are many biographies about her (here, here) so I'll just give the skinny on why she was chosen to be a conservation biology hero
1. She was a pioneer. She was a Japanese-American female working in field biology in the 1940's. Despite that she excelled as a scientist
2. She created a marine biology lab in Florida. Research labs are incredibly costly so hats off to her for getting it done.
3. She was an advocate for shark and marine conservation (hear a NPR story here).
4. She could talk the talk and walk the walk. She was an advocate and a great scientist. I looked her up on Web of Science and found a number of papers - including those in the late 1990's. She also had a Science paper - the top journal in the US.