The first is that he’s gaining weight, now that he has the wet-suit.
IF he was depressed, and stopped eating he would lose weight due to his activities and trying to stay warm. IF I pull numbers out of the air, to use for an example, let’s say that: IF he uses 500 calories p/hr to stay warm, and continues most of his daily activities he will lose weight if he reduces his caloric intake. That’s a given.

IF you give him a neoprene wetsuit he will stay warmer and burn fewer calories. A full suit can save you 40-60% of your caloric burn rate to stay warm (in MY personal experience). So he will gain weight.

If our penguin friend was depressed and the wetsuit has returned his normal life to him, AND he increases his caloric intake as a result of the depression being ameliorated, he will gain weight.

Which is probably why he gained weight. There is a problem that needs to be addressed here. Birds are easily stressed. They can become “picjers” or “pluckers”, and systematically pull out their feathers and make themselves bald, sometimes completely. Once they have a small bald spot they will worry it until, in extreme cases, they pluk themselves completely bald.

Since his wetsuit will form a physical obstruction between him and his feathers, he can’t reach them to pluck them. They are, as a result, growing back.

So, either the feathers are being rubbed off by something environmental in his habitat, perhaps something new, or he has chosen to rub himself against something, for some reason, until he has worn he feathers off (think scrapie,(a Spongiform Encephalopathie, Kuru, CJD, etc.) found in sheep, or there is some form of endoplucking by one or more of the the penguins in the paddock.

At any rate, if the feathers grow back under the neoprene they need to look at the cause of this penguin becoming bald. The only causes are:

1) Loss of feathers for some unknown reasons
2) Self plucking due to stress
3) Endogenous plucking by someone in the group, plucking him bald
(Common in birds at the lower end of the pecking order. He may have been supplanted as the Alpha male, which would change his position in the pecking order, [the social dynamic/hiararchy] and perhaps cause him to be “snatched bald”.)
4) The feathers have become rubbed off either due to stress, illness, accident, or normal activity in a recently changed habitat.

At any rate, they need to look at why this happened.

Cute article. Neoprene as a diagnostic tool. Who’da thunk it?