Whales Spotted Swimming Through Great Pacific Garbage Patch for First Time

Scientists have documented whales swimming through the Great Pacific Garbage Patch for the first time during an aerial survey of the ocean region. In total, 14 cetean individuals were spotted alongside 1,280 large pieces of plastic—equating to 90 pieces of waste per creature.

The survey, which took place in October 2016, was conducted by researchers working with The Ocean Cleanup, a nonprofit organization that looks to technology to remove plastic pollution from the world's seas. The scientists, led by Susan E. Gibbs, from the The Ocean Cleanup Foundation, have published their findings in the journal Marine Biodiversity.

The Great Pacific Garbage Patch is located between Hawaii and California and is the biggest accumulation of plastic waste in the world. It is one of Earth's five ocean gyres—huge systems of rotating ocean currents where marine debris tend to accumulate. The team say that while these "pollution hotspots" have been known about for many years, their impact on marine life is not well understood, with few surveys to record marine mammals having taken place in the areas.

"It is well known that ocean plastics pose a threat to marine mammals, with many cases of entanglement and ingestion interactions being recorded worldwide," they wrote. "Here, we describe the first cetacean sightings made within the so-called Great Pacific Garbage Patch."

The survey consisted of two flights, during which sensors were deployed and visual surveys were undertaken in order to create a "map" of the plastic from the sky. They saw at least 14 cetaceans, including three sperm whales—including a mother and her very young calf—three beaked whales and two baleen whales.

Study author Julia Reisser, from the University of Western Australia, said the team was surprised at the presence of so many cetaceans. "This is because this oceanic garbage patch is within what is called 'oligotrophic waters', which are believed to host a limited number of animals," she told Newsweek. "Our observations indicate that this plastic pollution hotspot is either home or an important migration corridor for many marine vertebrates, including whales."

The team also documented scores of plastic waste, such as ropes, floats and fishing nets. They said debris were seen close to where some of the whales were swimming, highlighting the risk they pose. Stories about plastic pollution and its impact on marine creatures are becoming increasingly prevalent.

In March, a marine biologist based in the Philippines found 88 pounds of plastic in the stomach of Cuvier's beaked whale. Just four months earlier, a sperm whale was found in Indonesia with over 1,000 pieces of plastic in its stomach, including a pair of flip flops and 115 drinking cups.

sperm whale and calf
Sperm whale calf and mother in the Great Pacific Garbage Patch. The Ocean Clean Up

Whales that use the Great Pacific Garbage Patch as a core habitat or as a migration route, the researchers said, are at risk of getting entangled or ingesting this debris. They also said it provides a greater insight into the movements of the species spotted, which is not well understood.

"The occurrence of a sperm whale mother and calf pair shows that individuals are using the region at various life stages. Sperm whale calves are born at around [13 foot] length, indicating the observed calf [about 14.7 foot in length] was very young," they wrote.

"Beaked whales (Ziphiidae) are widely distributed but remain one of the least researched families. They only spend a small proportion of their time at the surface…so the number of animals reported in this study represents a minimum present in the area surveyed. Our sightings of numerous ocean plastics of a wide range of sizes suggest that cetaceans within the [Great Pacific Garbage Patch] are likely impacted by plastic pollution, either through ingestion and/or entanglement interactions with debris items."

The team said the survey was not designed to look for animals living in the Great Pacific Garbage Patch, so observers may have missed other cetacean individuals. "Surveys with an optimised protocol for wildlife detection are necessary to acquire abundance estimates and density distributions of marine mammals within and around this area," they conclude. "Despite constraints, this study demonstrates that several cetacean species occur in the [Great Pacific Garbage Patch], thus supporting the need for further research to evaluate the risk of this plastic pollution hotspot to marine mammals."

This article has been updated to include quotes from Julia Reisser.