Researchers are rushing to figure out why more than 40 smalltooth sawfish have died in the Florida Keys. The species is critically endangered due to habitat loss and accidental catch by fisheries. #smalltoothsawfish #endangeredspecies #FloridaKeys Start your day with "Morning in America," NewsNation's live three-hour national morning newscast hosted by Markie Martin. Weekdays starting at 6a/5C. #MorningInAmerica NewsNation is your source for fact-based, unbiased news for all America. More from NewsNation: newsnationnow.com Get our app: trib.al/TBXgYpp Find us on cable: trib.al/YDOpGyG How to watch on TV or streaming: trib.al/Vu0Ikij