Juvenile Whale Hit by Boat Propeller Left With 'Severe' Head Injuries

A humpback whale has been left severely injured after being hit by a boat's propeller in Australia.

The 13-foot whale was reported to the Western Australian Department of Biodiversity, Conservation and Attractions (DBCA). A local spotted the injured creature off the coast of Dampier on Sunday, with a "severe boat propeller injury to the head."

"Whales are very vulnerable to ship strike as they need to regularly surface to breathe, and this can put them in the direct path of a vessel, particularly in busy shipping lanes," Graeme Shannon, a senior lecturer in zoology at Bangor University, Wales, told Newsweek.

"Despite their size, they can be very difficult to spot in open water, especially from the bridge of a large cargo ship, which can move comparatively fast," Shannon said. "Whales are also wide-ranging and can traverse entire oceans in some cases. They are therefore highly likely to come into contact with ships over the course of their movements, such as migration from wintering reproductive areas near the poles to summer feeding grounds in the tropics."

"DBCA and the Department of Primary Industries and Regional Development (DPIRD) Fisheries staff monitored the whale for several hours. Sadly, due to the extent of its injury, marine wildlife experts determined that its chance of surviving is extremely low, and the most humane course of action is euthanasia," Parks and Wildlife Service, Western Australia said in a Facebook post on Sunday.

The whale swam away into deeper waters after being monitored by authorities for several hours, and could not be found on Monday, escaping euthanasia but still severely injured.

"Despite search efforts yesterday, the injured whale has not been located," the post explains.

Humpback whales can grow up to 56 feet long at their largest, making this 13-foot whale likely a juvenile. These humpbacks were once severely threatened, with a worldwide population of only 5,000 in the 1960s. However, they have recovered since whaling was banned worldwide, with a current population of around 135,000. These whales are migratory, with some traveling up to 5,000 miles every season between breeding and feeding grounds.

"Shipping – along with most forms of transport – has rapidly increased over recent decades creating ever-greater opportunities for ship strike, which is compounded by the size and speed of the ships," Shannon said.

The waters off Western Australia are one such humpback migration highway, with over 30,000 of the creatures swimming along the coast between March and October. This puts them at risk from the large number of vessel movements along the same coast.

Vessel strikes are one of the major threats facing humpback whales, as well as entanglement in fishing gear and climate change, according to NOAA. Vessel strikes can occur as a whale approaches the water's surface to breathe, with the ship or boat not being able to spot the animal until it's too late.

"Whales do not always notice vessels in time to avoid a collision. It may be that the vessel is moving more quickly than they expect, or it is moving erratically and is hard to predict," Sarah Marley, a senior lecturer in ecology at Scotland's Rural College, told Newsweek.

"The main noise source for a vessel is the propeller at the rear, but for cargo ships, this can mean that the noisy propeller is a few hundred meters away from the pointy bow at the front, which whales do not realise and so struggle to avoid," Marley added. "If the whales are in a busy, noisy environment, it might also be difficult to pinpoint a specific ship moving towards them, much like if you were standing at the side of a busy motorway and trying to listen to just a single car."

Vessel strikes are deadly for several reasons, Niki Alsford, a professor in Asia Pacific Studies at the University of Central Lancashire in the U.K., told Newsweek.

"The size and speed are one factor. Large vessels like cargo ships, container ships, and cruise ships are significantly larger and faster than whales. When a fast-moving vessel collides with a comparatively slow-moving whale, the impact can be catastrophic. The size and force of the vessel can cause severe injuries or death to the whale," Alsford said.

"Vessel strikes may result in blunt-force trauma. The force can cause fractures, internal injuries, and damage to organs," Alsford added. "Even if the initial impact didn't immediately kill the whale, it can lead to internal bleeding and long-term health problems. In addition to the initial impact, the propellers can cause further harm. This might result in deep lacerations and amputations of fins or tails, all of which could be fatal."

Additionally, injured whales may be unable to swim, feed, or migrate properly, leading to an increased risk of predation and general ill health.

Only two months ago, a whale calf was hit by a tugboat in the same region of ocean off Western Australia, and the DBCA knows of six vessel strike incidents over the last two years.

Vessel strikes are also an issue for whales off the U.S. coasts, especially in California.

A spokesperson for the Marine Mammal Center previously told Newsweek: "The number of ship strikes here in the San Francisco Bay Area is highly variable and has averaged between four and six incidents the past several years."

Some places have implemented regulations and speed limits in known whale habitats to reduce the risk of strikes.

"One of the most effective ways of reducing ship strike of whales is for vessels to slow down. This not only reduces the likelihood of a ship strike occurring by giving whales time to evade the vessel, but it also means the potential severity of an impact is also reduced. Much like how we encourage car drivers to slow down in densely populated areas or around schools," Marley said.

"However, for this mitigation to be successful, what we really need is global cooperation. These whales are crossing international boundaries, exposing them to a variety of threats all with different management strategies," Marley added. "It would be great if we could all work together for a consistent, effective approach to whale conservation."

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