The Bay Area’s roads are getting more dangerous — and not just for motorists crowding the region’s highways. Increasingly, cyclists and pedestrians are getting killed on city streets, too.

The number of fatal car, motorcycle, bicycle and pedestrian collisions in the Bay Area jumped 43 percent from 2010 to 2016, according to newly released data from the Metropolitan Transportation Commission, the region’s transportation planning agency.

Yes, there are more people in the Bay Area living and driving here, which could account for some of the increase, said David Vautin, a researcher for the MTC. And, yes, more drivers are traveling from further away on increasingly long, mind-numbing commutes.

But, the rise in population and the growing number of miles commuters are traveling still don’t explain the uptick in the number of people dying on Bay Area highways and roads during that time, he said. There were 455 fatal crashes in 2016, compared with 318 in 2010. Five of the six years showed increases in fatalities, which followed four previous years of declines. But 2016 wasn’t the high point. In 2003, there were 509 fatal crashes, the most in the 16-year span studied.

Some experts point to the rise in “distracted driving,” people texting, calling or checking Facebook on the road, he said. Others blame the slow-down in life-saving advancements, like seat belts, anti-lock brakes, or shatter-proof windshields that manufacturers were quick to adopt, while new breakthroughs haven’t had as widespread a reach.

But, ultimately, the real culprit is human error, said Stephanie Mak, a data analyst with the MTC. She looked at fatal crash reports between 2010 and 2016 and found three factors topping the charts: speeding, unsafe turning and driving under the influence of drugs or alcohol.

“It’s unsafe driver behavior,” Mak said. Simple as that.

The Bay Area is not alone. Across the state and nationally, there’s been an uptick in fatal collisions since the Great Recession, said Chris Cochran, a spokesman for the California Office of Traffic Safety. In California, fatal collisions rose 33 percent between 2010 and 2016, he said. And that wasn’t entirely unexpected.

Typically, when the economy is bad, there are fewer people commuting or traveling for work or play. When the economy improves, more people hit the roads.

“Basically, we’ve seen a return to pre-recession statistics,” he said. “But, we’re in danger of moving beyond that.”

Some new technology in cars, such as interactive dashboards, can distract drivers, Cochran said. But other automated features, often called “driver-assist” technologies — like alarms that warn you when you drift out of your lane or are heading toward a collision — can help, he said. The most advanced features aren’t too common in most cars on the road today, though, and completely driverless cars, hailed as the zero-collision future, are still years away from mass adoption.

Until then, Mak said she’s been speaking with her counterparts at the state level and in other regional transportation planning agencies to see what they’re doing to stem fatal crashes and what the Bay Area could be doing better. That could mean more enforcement for speeding and impaired drivers, she said. Or, it could mean more educational campaigns for motorists.

In some cities, advocates are becoming increasingly vocal about safety on their streets, encouraging officials to design streets to make them safer. San Francisco, Fremont and San Jose have all pledged to join the growing “Vision Zero” movement, an effort to redesign local roads in ways that eliminate fatal crashes.

Those road redesigns appear to be working, said Cathy DeLuca, the director of policy and programs at Walk SF, a pedestrian advocacy organization. San Francisco adopted its Vision Zero policy in 2014, she said. Since then, it has has been able to buck the trends and saw a slight decrease in the number of fatal collisions in 2016. Although the data is preliminary, DeLuca said 2017 looks encouraging, with roughly one-third fewer deaths this year, she said.

In Alameda and Contra Costa counties, Ginger Jui, a spokesperson for the bicycle advocacy nonprofit group, Bike East Bay, pointed to an increase in the number of cyclists hitting the streets as a possible cause for a rise in fatal collisions. But, Jui also noted that more protected bike lanes and changes to city streets that slow speeding cars are saving lives.

“Whenever speeding is reduced, that’s good for everybody,” she said.