Democratic lawmakers were in Trenton on Thursday to hold what they said was a “science-based” approach to the recent marine mammal deaths off the Jersey Shore.

They said they wanted to discuss the deaths of whales and dolphins as part of the larger picture of a warming climate and not collateral damage from offshore wind development.

This was the Democrats’ turn to hold a hearing after Republican hearings held in Wildwood in March.

Republican state Sen. Anthony Bucco said that Thursday’s hearing was “one-sided” and said that Democrats “stacked the deck.” But Bucco himself led an independent virtual hearing into this issue last month, with no Democrats on the panel.

Thursday’s hearing had Republicans and Democrats on the panel – the Assembly Science, Innovation and Technology Committee.

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Democrats say they're bringing a science-based approach to the issue of marine mammal deaths. They said they desired a contrast to those hearings held by Republicans, which did include some scientists alongside activists, members of the fishing community and the Marine Mammal Stranding Center.

One scientist testified that the sonar being used to map the seabed ahead of the construction of wind turbines could "disorient" whales slightly, but that there was no chance they would die instantly from the sound. That scientist said that the sound waves overall would not have a significant impact on marine mammals.

Shawn LaTourette, commissioner of the state Department of Environmental Protection, said there was a similar unusual mortality event in 2013. He said those dolphin deaths in 2013 were the result of a virus.

LaTourette argued with Republicans on the committee, pushing back forcefully and saying climate change is the reason for the spate of recent marine mammal deaths.

"We do know. We do know. The changes to the environment in which these mammals exist is what is causing them,” LaTourette said. “It's not as if we don't know what is happening. We understand what's happening.”

LaTourette says that the warmer waters are causing the fish that whales feed on to move to different areas and when the whales follow these fish, it puts them into the paths of ships.

Republican state Assembly Member Antwan McClellan still suggested a pause on offshore wind development of anywhere from 60 to 120 days.