One of the world’s leading authorities on killer whales

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One of the world’s leading authorities on killer whales is a kind of Dr. Dolittle, who has spent decades listening to, rather than speaking to, marine mammals.

In an impressively influential career, University of Cumbria Associate Professor for Nature Conservation, Volker Deecke helps align international protection policies in a number of countries and has been at the forefront of raising public awareness.

He played a pivotal role in the prestigious research conducted by governments in Canada, Iceland, America and the UK to assess the status of killer whales in their waters.

Underwater acoustics have been critical in shaping conservation strategies for the largest member of the dolphin family, whose survival depends on addressing a number of pressing issues, and was key to Dr. Deecke’s studies.

He has developed techniques to literally eavesdrop on orca communications and has used the powerful signals to successfully collect vital data aimed at protecting populations and even saving some from extinction.

Although killer whales are among the most well-known and well-known cetaceans, they are classified as data deficient by the International Union for Conservation of Nature. Despite the lack of information, it is known that there are populations that are now considered vulnerable.

dr Deecke explained: “While those I have studied are reasonably healthy, southern residents in British Columbia, Washington state and the UK waters are slowly declining in numbers.

“Fortunately, our research is very collaborative and rather than one of us ‘saving’ a population, we are all contributing to a puzzle that will hopefully lead to better management and conservation strategies.”

In 27 years of research, the work of Dr. Deecke, particularly in communication tracking using digital recording tags, contributed to a better understanding of behavior, feeding and, most importantly, the effects of underwater noise.

Hearing telltale sounds is made possible by cellphone-sized acoustic tags fitted with four attached suction cups via a five-meter pole from a research boat to minimize interference.

“It was very exciting,” he admits, “unlocking new realms of understanding beneath the waves. Before that we limited ourselves to spotting whales on the surface. Tags have given us the ability to draw dive paths and record the sounds they recognize and make.

“Hearing them opens a fascinating window into their world. I like to close my eyes while listening and imagine what it’s like down there.

“You need precise knowledge of their behavior to approach them slowly and mark them. We may see a slight twitch, but data shows they are quickly resuming normal activities.

“Between 2009 and 2012, we tagged 34 northern Vancouver Island residents who were classified as ‘Vulnerable’ in Canada but have stable, even slightly increasing, populations.

“In 2019 we tagged six more and the results are being analyzed, particularly in comparison to Southerners, to explain the different trajectories. The work goes on.”

The biggest single concern comes from noise. Sounds from boats, marine sonars, industrial operations such as offshore wind farms and seismic surveys for oil and gas play a role for whales and dolphins.

dr Deecke explained: “Although there are increasing trends to deploy marine mammal spotters and to only continue operations when there are no sightings nearby, deep-diving and more distant animals go undetected but can still be affected.”

In the world’s first attempt of its kind, ships approaching Vancouver Harbor were asked to voluntarily slow down to minimize propeller and engine noise to reduce the impact on endangered orcas living in the south.

“Global shipping is an area where significant benefits could be realized by designing quieter commercial cargo vessels,” argues Dr. blanket. “The slow-speed test is the first step in creating economic incentives to reduce noise.

“Our work in western Canada has shown that even in this relatively remote area, northerners experienced some type of anthropogenic noise most of the time.

“However, the problem is even greater for Southerners in busy waterways between British Columbia and Washington State.

“There are technologies to make ships quieter. The military has used it for decades to make ships less detectable. Significant progress could be made in designing commercial freighters that generate less noise.”

To get to the bottom of it and understand life in the orca world, Dr. Literally listening to Deecke what they have to say, not just about noise pollution, but how and where they feed, their breeding patterns, what they like and what they like, crucially what bothers them.

This isn’t idle chatter, but important communication signals between animals so they can find and identify each other.

Their “language,” based on three sounds, echolocation clicks, whistles, and pulsed calls, speaks of navigating to find prey and spotting danger at remarkable distances of up to ten kilometers.

Impulse calls even have dialects, while clicks, which sound a bit like a creaking door, indicate objects around them and help identify and navigate prey.

Because they have excellent hearing, mammalian hunting populations use their calls sparingly so as not to alarm the food supplies they hunt.

dr Deecke was born in Germany and grew up in Austria, where his interest in animal behavior developed from an early age. While studying biology in Berlin, he found himself in Vancouver with the irresistible prospect of researching underwater communications.

Here he completed his Masters, studying the evolution of dialects in resident fish-eating orcas. It led to his doctorate at Scotland’s University of St Andrews and emphasis on the vocal behavior of mammalian killer whales in British Columbia and Alaska.

His deafening devices were also used on dolphins and seals. But it’s the beautiful, distinctive black and white orcas, with their sophisticated hunting techniques and convincing vocal qualities, often specific to a particular group and passed down through generations, that have taken center stage.

“Our research in Shetland and Iceland used photographic identification and analysis of calls to show how frequently people travel between the two countries – and helped us identify the several who are stranded.”

A male juvenile in Orkney was identified, successfully refloated and seen swimming away.

“In the 27 years that I’ve been studying killer whales, there have been remarkable changes, for better or worse,” he says.

“Persistent organic pollutants, toxic substances that take a long time to break down and accumulate in the food chain, pose significant challenges. The further up the food chain animals and plants are, the greater their exposure. Top predators like killer whales and polar bears are particularly at risk.

“Flame retardants, commonly used in plastics and textiles, can cause illness and death when the immune response is reduced. Many of the chemicals are regulated, but the impacts are global and will take centuries to remove from the environment.

“Effective protection requires that all nations within killer whale range work together and implement conservation measures.”

Where there have been encroachment and conservation laws, it has made a difference, as Dr. Deecke explained.

“Southerners and Icelanders were struck when individuals were trapped in aquariums for display. Fortunately, this ended in America in the mid-1970s and 10 years later in Icelandic waters.

“Different populations eat different things, but food supply is a big problem for some of them. Along the west coast of North America, mammal hunters have been badly affected by government culls of seals and sea lions, with serious consequences. Since this was stopped in the 1970s, they appear to have been fine in terms of survival and rebirth.

“However, those who eat fish, such as Southerners, are of particular concern as an important food source is Pacific salmon, particularly chinook, which is becoming increasingly rare due to habitat destruction and accounts for 80 percent of their diet.”

Work continues, with exciting plans to study killer whales in Scottish waters, but that’s another story.

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