Reptile & Amphibian Forums

I have obtained a recaptured, Adult Bullsnake that had been surviving outdoors for the past 2 years, since its escape.
My current collection of snakes contains all relitively young animals. Therefore I am not experienced with gravidity in any species.
Do adult females lay eggs anually?
Do they only lay eggs when they're fertile?
Are all Bullsnake species egg-layers?
Is it currently the season?
I've had "BillyBillie" My Bullsnake, for just under a year now. She has resently had a very reduced apetite (refusing rats?! WOW) eating only a couple of mice weekly. And reduced daytime activity, mostly sleeping now, instead of actively watching any and all movement in the room. I've also noticed an increase in girth, especially just in front of the tail.
Any Assistance, Thoughts, Etc..

I have not bred bulls, but many other species. As far as I know, all Pituophis comples are egg layers. Eggs are deposited in late spring/early summer. Infertile eggs may be deposited along with fertile ones, however eggs will not likely be produced without some male contact and/or breeding (even infertile ones). Females may produce yearly as long as food is plentiful.