Around the World in 80 Casts: Global Aquatic Wildlife Discoveries
A Weekly Roundup of the Bizarre, the Rare, and the Fascinating from the Deep
A Weekly Roundup of the Bizarre, the Rare, and the Fascinating from the Deep
The ocean is Earth's final frontier, an unfathomably vast realm where the majority of life remains entirely unknown to science. Every week, marine biologists, deep-sea explorers, and observant anglers pull back the curtain just a little bit more, revealing creatures that challenge our understanding of biology and evolution. The past seven days have been nothing short of extraordinary for aquatic discoveries.
From the icy, dark depths of the Coral Sea to a pristine freshwater lake straddling the US-Canada border, researchers have uncovered everything from prehistoric "ghost sharks" to a transmissible cancer spreading among catfish. This week's edition of Around the World in 80 Casts takes you on a global journey to explore the most unusual, bizarre, and fascinating aquatic wildlife discoveries of the past week.
1. The "Ghost Shark" of the Coral Sea: A Relic from the Age Before Dinosaurs
In a monumental announcement this week, the Ocean Census—a global initiative aimed at accelerating the discovery of marine life—revealed that scientists have identified an astonishing 1,121 new marine species in a single year. Among this staggering haul, one creature stands out as a true relic of the ancient oceans: a new species of Chimaera, commonly known as a "ghost shark."
Discovered during a recent expedition to the Coral Sea Marine Park, northeast of Australia, this mysterious deep-water dweller was found at depths between 800 and 840 meters. Chimaeras are distant relatives of sharks and rays, but their evolutionary path diverged nearly 400 million years ago, long before dinosaurs walked the Earth.
The newly discovered Chimaera species from the Coral Sea. Image Credit: CSIRO/Ocean Census
Unlike their shark cousins, ghost sharks have smooth, scaleless skin, and males possess retractable sexual appendages on their foreheads. They glide through the crushing pressure and absolute darkness of the midnight zone using large, wing-like pectoral fins, hunting for bottom-dwelling invertebrates. The discovery of this new species by CSIRO ichthyologist Dr. William White highlights how little we know about the deep trenches of the Coral Sea.
The Ocean Census initiative is racing against time to catalog marine life before it disappears. The discovery of this ghost shark is a stark reminder that our oceans are filled with ancient lineages that have quietly survived mass extinctions, only to be found by humans in the 21st century.
2. The Parasitic Melanoma: A First-of-its-Kind Contagious Cancer in Catfish
While deep-sea discoveries often dominate the headlines, one of the most shocking findings this week came from a freshwater lake right here in North America. In a study published in the journal Nature on July 22, scientists revealed the discovery of a transmissible cancer spreading among brown bullhead catfish in Lake Memphremagog, a waterbody shared by Vermont and Quebec.
For over a decade, anglers had been pulling up catfish afflicted with mysterious, raised black lesions. Some fish were entirely covered in what looked like an "inky-black leprosy." Initially suspected to be a viral infection or the result of pollution, the truth turned out to be far more bizarre. The lesions are a form of melanoma (skin cancer), but the cancer cells themselves act as infectious agents, spreading from fish to fish like a parasite.
A brown bullhead catfish from Lake Memphremagog showing the transmissible black melanoma lesions. Image Credit: Vermont Fish & Wildlife
This is an incredibly rare phenomenon. It marks only the fourth type of transmissible cancer ever found in the animal kingdom—joining the Tasmanian devil facial tumor, a venereal tumor in dogs, and leukemia-like diseases in bivalves—and it is the very first time such a disease has been identified in a freshwater species.
Researchers believe the cancer may spread during spawning, when bullheads cluster tightly together in shallow water, allowing physical contact. Because these catfish are scaleless, bottom-dwellers, they may also pick up free-floating cancer cells from the sediment. Interestingly, historical records suggest this disease might have been around for a long time; Henry David Thoreau described catfish with identical "velvet-black spots" in Massachusetts rivers back in 1852. The discovery opens up entirely new avenues for understanding how cancer evolves and survives outside a host body.
3. Uncharted Waters: Trinidad and Tobago's First Deep-Sea Expedition
The Caribbean Sea is famous for its vibrant, shallow coral reefs, but what lies beneath the sunlit zone has remained a profound mystery. That changed this week as a groundbreaking expedition concluded in the waters surrounding Trinidad and Tobago. From June 29th to July 28th, a Caribbean-led team of scientists aboard the advanced research vessel RV Falkor (too) explored the nation's deep ocean for the very first time.
Led by Trinidadian marine biologist Dr. Diva Amon and the NGO SpeSeas, the mission utilized the remotely operated vehicle (ROV) SuBastian to plunge thousands of meters into the abyss. Incredibly, 93% of Trinidad and Tobago's waters sit below scuba diving depths, representing the country's largest, yet least understood, ecosystem.
A bizarre, translucent deep-sea creature encountered by ROV SuBastian in the deep waters off Trinidad and Tobago. Image Credit: Schmidt Ocean Institute
The expedition broadcasted its dives live, allowing the world to watch as the ROV's lights illuminated alien landscapes. The team encountered bizarre gelatinous creatures, deep-sea corals, and species that are almost certainly new to science. Researchers estimate that more than 1,600 species may exist in these deep waters, with the vast majority currently undiscovered.
This mission is a monumental achievement not just for science, but for regional empowerment. Historically, deep-sea exploration has been dominated by wealthy, developed nations. By leading this expedition, Caribbean scientists are taking ownership of their own marine heritage, gathering the crucial data needed to protect these fragile, deep-water ecosystems from future exploitation.
4. The Pale Octopus and the Bizarre Benthos of the South Atlantic
Further south, another major deep-sea expedition wrapped up off the coast of Brazil, yielding a treasure trove of bizarre biological anomalies. During a two-week oceanic survey in the tropical South Atlantic, an international team of researchers uncovered what they believe to be at least 31 new deep-sea species.
The haul from the crushing depths includes previously unseen jellyfish, comb jellies, and strange marine worms. But perhaps the most striking finds were the deep-sea cephalopods. The team captured footage of a pale, ghostly octopus navigating a dense field of stark white, skeletal deep-water corals.
A pale deep-sea octopus moves across a field of deep-water corals discovered during the Brazilian expedition. Image Credit: Ocean Census/Researchers
Life in the deep ocean requires extreme adaptations. Creatures here must survive near-freezing temperatures, immense pressure, and a total lack of sunlight. Many of the newly discovered invertebrates utilize bioluminescence—creating their own light through chemical reactions—to attract prey, find mates, or confuse predators.
The Brazilian expedition, much like the Ocean Census and the Caribbean mission, underscores a critical reality: we are currently in a golden age of marine discovery. As technology improves, allowing ROVs and submersibles to reach the deepest, most inaccessible parts of the ocean, we are finding that the seafloor is not a barren wasteland, but a thriving, complex ecosystem teeming with bizarre and beautiful life.
The Ocean Still Holds Secrets
From the prehistoric ghost sharks of the Coral Sea to the parasitic cancers of Vermont's catfish, this week's discoveries prove that the aquatic world is far stranger than fiction. As we continue to push the boundaries of exploration—whether by dropping ROVs into the Caribbean abyss or utilizing advanced genomics to sequence fish tumors—we are constantly reminded of the incredible resilience and adaptability of life on Earth.
The ocean covers more than 70% of our planet, yet we have mapped and explored only a tiny fraction of it. Every cast of a line, every dive of a submersible, and every scientific survey has the potential to rewrite the textbooks. Stay tuned for next week's edition of Around the World in 80 Casts, as we continue to track the most unusual and fascinating discoveries from the deep. For more fishing news, gear reviews, and aquatic wildlife stories, visit us at nyangler.com. Until then, keep your lines tight and your mind open to the wonders of the water.
