They also start to eat less as they mature.
As a baby, my boy would finish an entire bowl of food in one night. Now, he'll only eat about half that bowl.
But we would need more background information before anyone can really make any suggestions.
As stated above, how many kibbles, has he lost weight.
Has anything changed? Lighting, heat, environment. What is the temperature at?
How old is your hedgehog?
Some older hedgehogs eventually need help with their food, whether it be crushing, or soaking so that it becomes soft.
He is only 136 days old, i don't really know how many months and imma start counting his kitty food. He has adapted to 72 and 73 degree environment, the only thing that has reaally changed is that it is getting colder outside and his cage was on the wall that was the other side outside wall. If that makes any sense, he used to finish off a full bowl and like on that wall that was the other side is the outside wall he ate a little at a time and my stepmom put him on the warmer wall and he finished off half the bowl. Other than that its the same.
So about four months old.
Another thought, do you have additional lighting for him during the day? I leave a light on all day in the hedgie room as they are sensitive to the shorter days in winter. You mentioned he ate better on the "warmer wall" so my thought would be to move him back or purchase additional heating. Some prefer warmer temperatures than others.
Counting kibble and weighing him will help you see if he is losing weight. Eating less wouldn't be a big deal if he's just maturing and not eating as much but losing weight isn't good.
Turbo is around the same age as your hedgie and he used to finish off a bowl when he was little, now though some nights he hardly touches it. I assumed this was because he had matured although i do give him a variety of food and some he eats more of than others, i assume this preference so maybe try giving him a different flavour. I was giving Turbo chicken flavoured cat food, then i gave him fish flavoured and he gobbles that up but leaves the chicken. He hasn't lost weight at all and he is a good weight and has remained at that i guess he's just a little fussy because he sure gobbles his treats down :lol: