Anderson Cabot Center Research
Redfern Asks Big Questions
About Earth’s Biggest Animals
This fall, the Anderson Cabot Center for Ocean Life welcomed Dr. Jessica Redfern as a Senior Scientist and Chair of the Spatial Ecology, Mapping, and Assessment Program (EcoMap).
She develops models of whale habitat and uses these models to find ways to minimize risks to whales.
“My research is about identifying areas where we expect there to be lots of whales and planning human activities in areas where there will be fewer whales,” Redfern says. “This planning ensures that we are using the ocean wisely and sustainably.”
Redfern comes to the Anderson Cabot Center from the National Oceanic and Atmospheric Administration’s Southwest Fisheries Science Center in La Jolla, California, where she developed models to map the spatial distribution of many ocean species. Her work began with efforts to help the U.S. Navy plan training exercises to mitigate their effects on marine mammals.
“My goal has always been to contribute to wildlife conservation. It’s something that’s really important to me, and all of my research has had a management application,” says Redfern.
In 2009, she began to focus on the risk of ship strikes, collisions between ships and large whales. New California air pollution regulations had shifted ship traffic farther offshore, and Redfern wondered what this change meant for the risk of ship strikes.
Her most recent paper uses multiple years of ship traffic and whale data to examine the risk of ship strikes for fin, humpback, and blue whales in waters off California. Most studies use a single year of shipping data and a single map of whale distributions that represents average patterns. Redfern’s study is novel because it looks at how changes in both ship traffic and whale distributions affect the risk of ship strikes.
As expected, the location of shipping traffic had an effect on risk. Blue and humpback whales tend to occur nearshore, so risk increased for them whenever ships traveled closer to the coast. Conversely, fin whales, which occur offshore in many regions off California, generally had higher risk when ships traveled farther from the coast.
What was surprising was that the traffic pattern with the highest risk (i.e., ships traveling close to or far from the coast) was the same across all years of whale data.
The risk didn’t change because the whales were returning to the same feeding grounds. The consistency in risk is the key to finding management solutions – it means shipping lanes, speed limits, or no-go zones could help minimize risk as long as they are planned in relation to these areas with consistently higher numbers of whales.
But management solutions aren’t straightforward when offshore traffic is good for blue and humpback whales but dangerous for fin whales. In a paper that came out in July 2019, Redfern and her team helped stakeholders find ways to minimize ship strike risk off southern California. Stakeholders included the shipping industry, conservation organizations, air pollution control districts, and several government agencies. They found that expanding the area to be avoided surrounding the Channel Islands National Marine Sanctuary was acceptable to all stakeholders and reduced risk for all three whale species.
“It’s a solution that is a win for all the different stakeholders and a win for the whales. That, to me, is the most exciting scenario.”
The East Coast presents new challenges. As waters warm, the North Atlantic right whale’s range is shifting. How do you manage a species with a changing habitat? Redfern believes that will be an important question to pursue.
“There’s already great work being done here and groups that I’m excited to collaborate with,” says Redfern. “I’m also excited about the tools I’ve developed and how they can be used to solve conservation challenges.”