On March 30, 2003, about 0615 eastern standard time, a Beech A36, N4315S, registered to and operated by a private individual as a Title 14 CFR Part 91 personal flight, crashed during takeoff at Tavernaero Park, Tavernier, Florida. Visual meteorological conditions prevailed, and an instrument flight rules flight plan was filed. The private-rated pilot and pilot-rated passenger received minor injuries, and two other passengers received no injuries. The airplane incurred substantial damage. The flight was originating at the time of the accident. The pilot stated that he was seated in the left seat, and was the pilot operating the flight controls during the takeoff roll. He said that during the takeoff a dog suddenly appeared in front of the airplane, and the next thing he remembered was that the airplane banked left, and collided with trees lining the left side of the runway. The pilot-rated passenger/owner of the airplane said that when he saw an animal appear in front of the airplane during the takeoff roll, in an attempt to avoid a collision with the animal he applied back pressure to the control column to get the airplane airborne. He said he remembered the airplane veering to the left, and he tried to apply right rudder, and pushed the control column forward in an attempt to keep the airplane in ground effect. He said the airplane collided with trees lining the left side of the runway. Both the pilot and passenger/owner stated that prior to the accident there had been no mechanical failures or malfunctions to the airplane or any of its systems.