Why the chase goes before the appetite does
An elderly bearded dragon who ignores a cricket sprinting past has usually not lost interest in food — he has lost the speed, eyesight sharpness, or joint comfort that hunting demands. Chasing fast prey was doing two jobs at once in his younger years: it delivered protein, and it was his main daily exercise. When the chase stops, both jobs stop together, and that is why an older dragon can soften and lose muscle along his thighs, hips, and tail base even while his vivarium, temperatures, and diet on paper have not changed. The fix is to separate the two jobs and provide each one in a form his older body can still manage.
Bring the prey to him, at his speed
Slow the food down rather than giving up on live food altogether. Roaches, silkworms, hornworms, and black soldier fly larvae are all substantially slower than crickets, and most can be offered in a smooth-sided dish he can walk up to and pick from without anything escaping into the substrate. Tong-feeding works well for a dragon who still strikes at food near his mouth: present the insect just in front of his face and let him take it at his own pace rather than dropping it in to be hunted. Keep the protein quality where it was — gut-load the insects and dust them as you always have — because it is precisely the protein and calcium intake that maintains muscle and bone in a senior. If he will only take a few insects at a sitting, offer smaller feeds more often rather than one large one he walks away from.
Movement that does not depend on hunting
Replace the exercise, not just the meal. Short supervised sessions out of the vivarium on a warm floor with some grip underfoot — a towel or mat rather than slippery laminate — encourage a slow wander that works legs and core without any chasing. Shallow warm-water soaks, deep enough for him to paddle gently but never over his elbows without support, give low-impact movement that also helps hydration and shedding. Inside the vivarium, arrange his world so daily life still involves small journeys: basking spot, food dish, and cool hide in three places rather than one corner, with low, stable routes between them he can manage comfortably. Five unhurried minutes of movement several times a day does more for an old dragon's muscle than one exhausting session.
Watch the places muscle disappears first
Check his body the way a vet would: look down on him from above for the hip bones and the base of the tail, which should stay fleshy and rounded rather than pinched or bony, and feel the thighs, which lose bulk early. Weigh him every couple of weeks on a kitchen scale, at the same time of day, and write the figure down rather than trusting memory — a slow drift of a few grams a month is invisible to the eye and obvious on paper. Appetite changes in a senior are worth the same attention: eating less because he moves less is expected, but eating well while still losing weight is a pattern that needs explaining.
When slowing down stops being normal ageing
Most elderly dragons who stop chasing are simply old, and the routine above keeps them in good condition for a long time. But contact a reptile vet if the reluctance to hunt arrives with weight loss despite good feeding, if his limbs tremble or feel weak when he walks, if he stops basking or hides all day, or if his mouth, jaw, or eyes look different — an old dragon can be masking pain from joints, mouth problems, or organ issues that no feeding adjustment will fix. Bring your records to that appointment: keeping his weights, appetite notes, and feeding changes together in his KinsLe Pet Passport gives the vet the pattern over months, which is exactly what separates normal ageing from something that needs treatment.