If you want to eat the deer you'll have to cook it first. then your dragons can also have some

I cut off another piece and slowly approach it and call Arctic over quietly, attempting to make them comfortable around each other.

It looks at it closely then to your surprise it lets out a high-pitched whistle and the spikes on the cactus are lapped up. he chews them and swallows, leaving the rest of the cacti un-eaten

I look at it curiously. I get the other piece of cactus and hold it out, the spikes sharp on my bare hand.

You wonder around and are delighted to see that hidden away in some bushes is a nest with some eggs!

Unfortunately before you can do anything you hear a loud screech and turn around to see what looks like the mother fighting off another older stronger dragon. What will you do?

Quietly take a egg and sneak off into a distance where they can't see me then run.

Ok, I look for some sticks and dry leaves in forest. If I find them rub sticks together as fast as I can after arranging them.

Arctic steps closer carefully and sniffs the older dragon. the other dragons eyes narrow and he looks at Arctic apprehensively but does not attack. Perhaps you can train him ti defend Arctic as he is still a hatchling?

It does the high-pitched whistle again and eats the spikes. It swallows and rumbles what you believe to be a thank you. However you are not sure what type of dragon it is just yet. perhaps you can take it to the dragon trader to find out? or you could continue to explore.
(If you want a picture of the dragon let me know)

Wow Spinosaurus, that poor mother! XD