I have been a fan of babyback ribs and I have smoked them in my Traeger for years. I remove the membrane first off the babybacks. I harvested a bull nilgai last week and I have two large racks of nilgai ribs that I want to finish off first to make room in the freezer. Do you remove the membrane if its easy like removing them off babybacks or is it tough? If you don't remove the membrane, do you smoke them longer? Any recipes for smoking nilgai ribs? Thanks guys if you have any recommendations.

Nilgai ribs are going to be lean and full of silverskin (beyond the membrane). Applying only a dry heat application like smoking might work, but will probably end up very dry. The membrane is collagen, which will eventually melt into gelatin if kept at higher temps for sustained amounts of time. I personally don't remove the membrane on ribs (domestic or wild). In my opinion, the membrane serves to insulate leaner game meats.
Domestic pork ribs-even the leanest cuts like babybacks-have a lot more fat than a deer or antelope. I would recommend at least smoking them covered/wrapped for a while to achieve tenderness, then finishing uncovered while incorporating a sauce or mop that contained fat, like melted butter or even lard.
Smoking meats is such a universal cooking method for all of us that we forget sometimes that it is typically done with the fattiest domestic cuts like sausage, brisket and bellies (ribs). Translating these dry heat methods to extremely lean game can just dry it out if not done with a lot of precision and attention. Unless I'm dealing with a pretty fat feral hog, I'll almost always incorporate a par-cooking method when smoking. This could be mean an initial cook while the cut is wrapped in the smoker, wrapped and cooked the oven, or even poached at low temperatures in water or stock until tender, and then finished over direct or indirect heat of a grill or smoker while incorporating a sauce to restore some moisture.

Good information, thanks

Following up with Jesse's comments here: You can treat these ribs almost like Osso Bucco, as long as you're adding a fat to prevent them from drying out. I'd use a rich beef bone stock, with butter or oils and all your favorite herbs to braise the ribs to near tenderness, then remove the lid to your pot and finish it on the smoker. Or if you want to have more fun, use a dutch oven to start it and finish it lid off.