Penguin fish is weighed out to the gram in the kitchen and weighed back in at the end of the feed, and every bird is weighed weekly, so the colony's intake is a number the vet reads. Ours eat two kilos a day more than the birds can hold, and the birds are not gaining, and the fish store's stock goes down by exactly that.
I am the keeper in charge of the penguins, and the fish kitchen is where my day starts.
How the feeding is measured.
Each bird has a daily ration by weight, adjusted for the season and the moult. The fish is weighed out on the kitchen scales for the whole colony, taken to the pool in buckets, fed by hand so we know who ate, and what comes back is weighed. The difference is what the colony ate, and it is written in the book against the number of birds.
Every bird is weighed weekly on a platform scale they walk over for a fish. Intake and weight are read together, because a colony eating more and not gaining is a colony with a problem.
Ours eats about two kilos a day more than the sum of its rations, and has done for six years.
The birds are not gaining. They are, all of them, exactly the weights they should be, week on week, on a scale I calibrate.
Two kilos of fish a day is about a bird's worth. A big bird, eating well.
We do not have a bird more than the count. They are all ringed, all chipped, and the count is done twice a day by two keepers and it is the count.
What has been checked.
The scales. Kitchen and platform both, calibrated, and the fish weighed on the vet's scales on a random day. Same.
The feed. It is hand fed. You stand in the pool with a bucket and you give each bird its fish, one at a time, and you count, and I have counted for six years. Every fish that goes out of the bucket goes into a bird I can name. And the bucket comes back two kilos lighter than the fish I can account for.
The store. The fish is frozen in blocks, weighed in, and the stock is reconciled monthly. The store loses what the kitchen says, which is two kilos a day over what the birds get. The fish is leaving the building.
Theft. There is a camera in the kitchen and one on the store and a keeper in the pool. Nobody takes fish. The two kilos goes out of the bucket in the pool, during the feed, in the space of the twenty minutes the feed takes, from a bucket in my hand.
What I have seen, which is the part I did not put in the book for four years.
Feeding is done in a set order round the pool, and there is a place at the far end, by the old ramp, where the birds do not stand. They leave a gap there the way birds leave a gap round something.
I have never fed anything there. The bucket, when I get to that point in the round, is lighter than it was at the previous bird, by about a fish, every time, and I have weighed the bucket on a hand scale at that point on eleven feeds to be sure, and it is.
Two kilos a day, a fish at a time, out of a bucket in my hand, at a place in the pool where the colony leaves a space.
What is done about it.
The ration sheet has a line for it. It is called wastage, which is what any keeper would call an unexplained loss, and the vet has seen the line and has never asked about it, because the birds are well and the line is small.
What I do.
I feed the colony.
The one thing I have changed is that I fill that gap.
I feed at the far end by the ramp now, one fish, to nothing, held out over the water at the place the birds leave, and it goes, out of my fingers, the way a fish goes when a penguin takes it, with the small tug, and the bucket is right by the end of the round.
The wastage line reads zero since I started, and the birds stand closer to the ramp than they did, and on the platform scale, on a Wednesday in the spring, between the last bird and me stepping on to zero it, the scale read a bird's weight, four point one kilos, for the length of time a bird stands on it, with nothing on it that I could see.