Scientists using advanced mathematical models to examine the distribution of open-ocean animals in the North Pacific have concluded that rising ocean temperatures could lead to a significant shift in critical ocean habitats.

Results from a two-year Center for Ocean Solutions study, published in the scientific journal Nature Climate Change, indicate that while some critical habitat areas, such as the California Current, which runs along the West Coast, will experience few ill effects from warming conditions, others, like the massive North Pacific Transition Zone, could undergo dramatic change over the next 100 years.

The study applied mathematical models to data collected from the Tagging of Pacific Predators project of the global Census of Marine Life, in which 4,300 electronic tags were used to track the movements and migration patterns of 23 species from 2000 to 2009.

Satellite measurements of sea-surface temperature and chlorophyll, combined with the tracking data, were used to identify "key habitat areas" for different ocean predators. Climate models of ocean temperature and productivity were used to predict how those areas might change with ocean warming.

The North Pacific Transition Zone, so named because of the mixing of cold, nutrient-rich water from the north and warmer, nutrient-poor water from the south within its boundaries, is an important corridor across the Pacific basin for many ocean predators. The study indicated that the region could shift by as much as 600 miles north, resulting in a 20 percent loss of species diversity within the region.

"What was not surprising to us was that there would be winners and losers as a result of these changes," said lead author Elliot Hazen, a research oceanographer at the University of Hawaii and a National Oceanic and Atmospheric Administration researcher affiliated with the Center for Ocean Solutions at Stanford University. "What was surprising was the distance that (the North Pacific Transition Zone) could move."

Predicted losses in essential habitat due to Pacific warming have been estimated as high as 35 percent, endangering top ocean predators such as sharks and turtles and marine mammals like the blue whale. Animals with greater adaptability to temperature, such as albatross or tuna, could actually benefit from the shift.

Hazen said the scientific modeling used in the study should encourage a more dynamic strategy for managing marine and coastal resources, allowing regulators to better anticipate and react to changing ocean conditions.