Study Projects Gulf of Maine Less Suitable for Right Whales by 2050

11-02-2021

New research led by Bigelow Laboratory for Ocean Sciences sheds light on potential future habitats for critically endangered North Atlantic right whales. The study shows how keeping a close watch on environmental changes will be key to aiding conservation and management efforts to restore the whales’ population. It was published as part of a collaborative report that takes a comprehensive scientific look at changes expected in the Gulf of Maine by 2050.

“Predicting future habitat conditions for whales can help us understand where we might want to focus more population surveys next,” said Camille Ross, the study’s primary author who is also a Bigelow Laboratory research technician and University of Maine graduate student. “That's incredibly important because we can put conservation measures in place in these areas before it's too late.”

Large whales play a critical ecological role in the environment. They are a fundamental part of the food chain, recycle large amounts of nutrients, and help remove excess carbon from seawater. However, North Atlantic right whales are one of the most endangered animals on the planet. Commercial whaling brought the species to the brink of extinction in the 1890s, and there are currently only about 350 of them in existence. Efforts to restore the population have proven particularly challenging, as their natural habits overlap with regions used for shipping, fishing, and other commercial uses.

Climate change has further complicated the efforts. Historically, North Atlantic right whales frequented the same locations each year. This predictable behavior made it more feasible to design and evaluate the potential impact of regulations, such as moving a shipping lane or closing a fishing zone.

In 2010, a significant shift occurred in the whales’ behavior, which was later explained by Bigelow Laboratory research. Warming deep water temperatures changed the location of a key food source, and thereby the whales’ regular seasonal use of feeding grounds. This led to a dramatic increase in accidental deaths from ship strikes and entanglement with fishing gear – driving down the population’s numbers, which had been slowly recovering. Identifying the new locations that are most likely to be used by the whales in the future can help the efforts to conserve, and hopefully rebuild, the population.

“If the whales don't know where their food is going to be, they wind up going all around looking for it and can show up in more places than we are used to,” said Bigelow Laboratory Senior Research Scientist Nick Record, a co-author on the paper. “That's why they've more frequently been getting struck by ships and entangled in gear, and why we urgently need to understand where the changes in their environment are leading them.”

The new study combined an ensemble of computer models with historical data to define the type of habitats that have traditionally been most suitable for whales. Those habitat conditions were then located under a range of climate scenarios for 2050 to suggest where the whales may go. The results indicated decreased habitat suitability across most of the Gulf of Maine from July through October, but also showed increases in some unexpected zones.

Identifying likely future habitats that fall outside of the current conservation focus is increasingly important. The research suggests that there may be a large population shift out of important historical habitats such as the Bay of Fundy, where there were no recorded whale sightings in 2020. However, there may be an increase in potential habitat on the Scotian Shelf and Roseway Basin, which currently have few whale population surveys.

“Population distributions have shifted in the past, and they're likely to shift again in the future due to climate change,” Ross said. “Anything we can do to try to understand where they might shift to will help us put conservation measures in place in those areas before more unnecessary mortalities occur.”

The research was published as part of a comprehensive report by an interdisciplinary group of scientists that came together to draw a full environmental picture of the Gulf of Maine’s future.

Record is also a co-author on a paper that summarizes the group’s findings, and the primary author on a paper about harmful algal bloom predictions for 2050. Those blooms, which can have significant negative effects on humans and animals, are increasing in frequency while changing in ways that don’t fit with expected patterns.

“We've already seen that it’s the changes we weren't expecting that really force our hands,” Record said. “They force management decisions, closures of fisheries, or other new regulations because we have to immediately respond after the problem has already taken hold.”

These new studies are designed to give policymakers, conservationists, and other decision makers the tools to preemptively craft science-based approaches to the pressing issues facing the Gulf of Maine.

“This is a chance for the whole scientific community to come together and try to be a little bit more proactive to hopefully inform some of today’s decisions,” Record said. “Today, when we get together with the management teams, we're talking about decisions that were made in the 90s. People will likely be sitting around the table in 2050 discussing the decisions we’re making right now.”

Photo Credit: Amy Knowlton, Anderson Cabot Center / New England Aquarium under NMFS Permit #15415.