male biting female's neck

by Lori
(Pennsylvania)

My male Red Earred Slider keeps biting the female Yellow Bellied Slider's neck. They have had eggs numerous times, but we have opted to discard them. Is this biting part of their mating ritual or is he being aggresive? We are debating on getting rid of the male and just keeping the female, as they are in a 75 gallon tank and we have no room to seperate them into seperate tanks.