Nat Geo Sharkathon | 'World's Biggest Tiger Shark?': The day a giant solved a gruesome murder
Tiger sharks are one of the most fascinating creatures in the ocean and the second deadliest shark species after the Great White. Its name derives from the dark stripes down its body, which resembles a tiger's pattern, but fades as the shark matures. Baby tiger sharks are covered in roundish gray spots that fuse into stripes as the sharks mature. As part of National Geographic's 'Sharkfest', the network is airing the documentary 'World's Biggest Tiger Shark?', which features marine biologist Kori Garza and Emmy Award-winning underwater cinematographer Andy Casagrande traveling to French Polynesia to film Kamakai, the biggest tiger shark Garza had ever encountered. French Polynesia banned hunting sharks in 2006, which meant Garza can only observe the tiger sharks in the sanctuary and not tag them.
Garza reveals that the ban on shark fishing may be one of the reasons as to why Kamakai grew so big — the creation of the healthy sanctuary for sharks has seen the tiger shark population in the area increase. She also noticed that many tiger sharks moved together, as opposed to the notion that they were solitary hunters. Tiger sharks eat nearly everything—- from birds like albatrosses to ocean creatures such as venomous sea snakes and other sharks, and even manmade objects like paint cans, leather jackets, rubber tires, and even license plates.
A healthy shark population also helps in improving the ecosystem and this is quite true for the tiger shark as well. In Australia's Shark Bay — which is home to many different species, including 28 shark species that have been spotted there — seagrass forms the backbone of the ecosystem by providing shelter for small animals and food for big herbivores. However, a heatwave in 2011 decimated the seagrass growing there. The flora has been making a gradual comeback, but scientists noticed that the seagrass grows at a higher rate in places frequented by tiger sharks — this could be because the sharks frighten off the sea turtles and dugongs (a marine mammal that is related to the manatee) who like to eat the grass.
Tiger sharks may also be the "Goldilocks" of the shark species in that they prefer a "just right" temperature when it comes to where they stay. The species are seen in tropical to warm temperate waters all over the world and ocean temperature of 71.6 degrees Fahrenheit would be ideal for them. One of the reasons the tiger sharks are so feared is because of their notched teeth that point sideways. The tiger shark's teeth have dual functions — they help the shark hold on to struggling victims and can also help them shear right through the thickest of hides, meaning that the tiger shark is well-equipped to go after any prey in the ocean. One of those preys is the sea turtle. However, a 2016 study showed that the sharks tended to avoid healthy turtles and instead conserve energy by going after sick, dying, or dead turtles.
Of course, the most fascinating thing about a tiger shark that once existed is that it almost helped to solve a murder mystery back in 1935. The Coogee Aquarium in Sydney, Australia was looking for a big fish to occupy its newly-built pool, and a 13-foot tiger shark was captured for it. The shark was a big hit but seven days after its arrival, it vomited up a bird, a rat, some nasty brown goo, and a human arm, which had a rope tied around its wrist and a forearm tattoo of two boxers. That tattoo helped identify that the arm belonged to James Smith, an amateur boxer who had recently gone missing. Forensic analysis showed that the arm had not been bitten off — it had been removed from Smith's body with a knife.
Smith's longtime associate, Patrick Brady, was soon a suspect after detectives learned that Smith was last seen playing cards with him at the Hotel Cecil in Cronulla. The authorities were later informed by a boat-builder (and suspected criminal) named Reginald Holmes that Brady had murdered Smith in an argument. But before Holmes could testify in court, somebody shot him. Brady got free of the murder charge after his lawyers argued that a severed arm did not constitute proof of a murder and that Smith might still be alive somewhere. The tiger shark was not as lucky — it died in captivity.
'World's Biggest Tiger Shark?' premieres on July 19 at 8/7c on National Geographic. An encore presentation will follow on August 11 at 9/8c on Nat Geo Wild.