A Big Story for a Little Goose!

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A male cotton pygmy goose relaxes on a log.

In my previous post about white-faced whistling ducks (They Whistle, But Are They Ducks?), I mentioned that they were more closely related to a Canada goose than they were to a mallard. Well, cotton pygmy geese belong to the Anatinae subfamily, meaning they are more closely related to a duck than they are a goose! Why the misnomer? Take one look at this bird, and you will probably forgive anyone for thinking that they are a very small goose; their head shape and small pointy bill certainly looks very “gooselike.” While these shy birds are always fun to work with, something has happened recently that has thrust them into the spotlight: babies!

The Owens Aviary at the San Diego Zoo has been home to cotton pygmy geese for many years. While most visitors are awed by the colorful and loud birds swarming about their heads, these birds lead a peaceful and unassuming life in the lowest pool of the aviary. This past May, one of the regular aviary keepers noticed that the female goose wasn’t in the pool with her mate. After searching a number of her favorite hiding places, he started checking the nest boxes that surround the lowest pool. Cotton pygmy geese prefer to make their nest in a cavity like those found in dead trees…or in nest boxes strategically placed by keepers. After a quick search, the keeper found the missing hen in one of those boxes. She was on a clutch of eggs!

We were excited at the idea of having a gaggle of goslings running around the lower half of the aviary, but there was a question about what to do with the male. Remember that these birds behave more like a duck, and the cotton pygmy goose male doesn’t help to raise his young. After some debate, we decided to leave the male in the exhibit and keep a close eye on his behavior.

On June 14, 2012, the eggs hatched! My first view of them was from the top walkway of the aviary looking down at the lowest pool. Initially I saw…nothing! Not a sign of Mom, Dad, or their seven newest additions. Undaunted, I tossed a handful of crickets into the water some 50 feet below. Dad poked his head out, looked up at me, and then made a beeline to the mass of crickets. Taking their cue from Dad, seven tiny goslings came rushing out from the logs, grasses, and rocks to chow down. Even wary Mom slowly swam out to nibble at a few bugs. I was overjoyed to see the family of nine geese doing so well.

We watched with surprise at how confident the goslings had become in just a few days. In previous years, we were used to goslings that were experts at staying invisible. One year, a team of keepers had to be called in just to get a full count of four goslings! Not this group. These guys only need a few pieces of millet to encourage them to come a-paddling. Keepers think there are a few reasons this group of goslings is so visible and active:

1) There are more goslings in this group than there have been in past years (aren’t you more comfortable in new situations if you’re with a large group of friends?).

2) The male is such a calm and confident influence on his young. It seems that even though the male doesn’t take care of the goslings directly, the female and her young may draw confidence from his calm behavior. Pretty cool!

The young have grown up so fast that it can be hard to tell the babies from their mom—she is slightly bigger. But if you happen to visit Owens Aviary, be sure to take a moment to look down and say hi to the baby goslings!

Mike Grue is a senior keeper at the San Diego Zoo.