• 
  Gerardo Aldana

  10 episodes, 2017
• 
  Oscar Miro-Quesada

  11 episodes, 2017
• 
  Vidal Haddad Jr.

  8 episodes, 2017
• 
  Rui Seabra Ferreira Jr.

  8 episodes, 2017
• 
  Sebastian Arredondo

  unknown episodes
• 
  Bob Brisbane

  12 episodes, 2017
• 
  Paul Rosolie

  5 episodes, 2017
• 
  Bryan Grieg Fry

  5 episodes, 2017

• 
  Justin Schmidt

  8 episodes, 2017
• 
  Dean Ripa

  5 episodes, 2017
• 
  William Muth

  5 episodes, 2017
• 
  Brien Foerster

  9 episodes, 2017
• 
  Richard Rasmussen

  8 episodes, 2017
• 
  Greivin Carrales

  5 episodes, 2017
• 
  Richard Rasmussen

  7 episodes, 2017

• 
  Gregory Erickson

  Self - Crocodilian Biologist
• 
  Mahmood Sasa Marin

  Self - Professor and Biologist of Clodomiro Picado Research Institute
• 
  Martin Nicholas

  Self - Spider Expert
• 
  Greta Binford

  Self - Associate Professor of Biology at Lewis & Clarke College
• 
  George Burgess

  Self - Director of Florida Program for Shark Research
• 
  Ian Recchio

  Self - Herpotologist
• 
  Florian Graner

  Self - Marine Biologist and Filmmaker