A Clearwater bicyclist is dead Sunday after a tree branch became stuck in his spokes on the Dunedin Causeway and caused him to flip over his handlebars, deputies say. 

Henry J. Ellowitz, 69, was riding his bicycle on Causeway Boulevard on Sunday afternoon. He was the top of the drawbridge traveling east, about to head down, when Pinellas County Sheriff's deputies say they believe he struck a tree branch sometime around 4:15 p.m. 

Deputies from the Major Accident Investigation Team said the branch became lodged in his front spokes causing his front tire to lock. As a result, Ellowitz vaulted over the handlebars.

Two witnesses who were in vehicles traveling in the same direction as Ellowitz stopped immediately and began to assist him.

Dunedin certified nurse assistant Jill Kurtzke, 53, and Tampa EMT David Rogers, 41, found Ellowitz unresponsive, deputies report.

They began CPR and continued until Dunedin Fire Rescue paramedics arrived, deputies report.

Ellowitz was taken to Mease Dunedin Hospital, where he was pronounced dead at 5:16 p.m., deputies report.

The Causeway closed to traffic for 20 minutes initially, and then reopened to one lane of traffic until deputies completed their investigation.

Ellowitz was wearing a helmet, deputies report.