And sure enough, his weight was off.
Had it been daytime, we would have likely rushed to the vet. However, there was a simple explanation at hand and it turned out to the be the problem.
While Piper does eat his fruits, veggies and pellets, he still eats seeds. Recently, we have experienced trouble finding the regular seed/nut mix we give to the birds so we had to try something different. The Boy bought a bag of this different food and started to give it to the birds. To be honest, if I look at the weights I got at the very end of October, Piper's was slowly going down (but was still within normal) - turns out, he wasn't a fan of the new food and, having taken a closer look at it, it did look like the elements in the food mix were too large for him. So, on November 5, the Boy went to get another mix I knew Piper had eaten in the past and that made Piper happy.
All that to say, having a record of Piper's regular weight, as well as being able to see when things started to go bad and being able to match it with an actual change that happened in the household meant we were able to find a solution.
So let's get to the actual data.
Average weight (in grams) for November 2015:
Piper - 54g
Shade - 116g
Joey - 126g
Petey - 141g
Zuri - 127g
Pixel - 122g
Léa - 315g
Updated table - average weights for each bird per year:
|*For 2015, data from January to November is included.|