Name That Goose!

Lift-off at Hagerman NWR, by Lee Hatfield

Geese have been arriving over the past few weeks to spend the winter at Hagerman National Wildlife Refuge and the huge flock, estimated this week at 10,000, is a popular sight for visitors there.   Here are two questions frequently asked, related to the geese, and answers to help identify the various species.

1.  “What do you mean Snow Goose or Ross’s Goose? They all look the same to me!”

That’s true, until you start looking more closely. Ross’s Geese are smaller than Snow Geese, but the relative size can be hard to distinguish when you are looking at a flock of a thousand or more white geese. Instead, look at the shape of the head and bill.

The Ross’s head is more rounded, with a stubby bill which appears thicker at the base. The border at the base of the bill is straight and vertical.  

Ross's Goose, by Rick Cantu

The head of the Snow Goose is more wedge-shaped, with a longer appearing bill. There is a black line between the upper and lower mandibles, or bill, known as a “grin patch”; the base of the bill is more curved that on the Ross’s.

Here are some memory cues – Snow Goose – sloping forehead; Ross’s Goose – round head.

Snow Geese, Blue Phase on left, by Rick Cantu

2.   “Okay, but what are those dark colored geese in with the ‘Snow Geese’”?

The dark colored geese with white heads are dark phase Snow Geese. These were once called the Blue Goose. They will not become white over time, but are a variation.  Dark phase is rare with Ross’s Geese.

A website that is helpful in learning these distinctions is http://www.sdakotabirds.com/diffids/snow_vs_ross.htm.

You may also see a small flock of grayish-brown geese with white foreheads alongside the white Snow and Ross’s geese; these would be the Greater White-fronted Geese shown below.

Photo by Dick Malnory

Next time you go out to see the geese, take your binoculars, or borrow some from the Visitor Center, so that you can take a close look at the head and bill shape and you will find that you can identify the different species!

The winter waterfowl at the Refuge will be the topic for both Youth FIRST, on December 7, and Second Saturday, on December 14, when Dr.  Wayne Meyer will give a presentation.  A guided tour, aboard a TAPS bus, along Wildlife Drive will be offered on both dates as part of the program.

For more information about activities at the Refuge, please check our website, http://www.friendsofhagerman.com . The official site for Hagerman NWR is http://www.fws.gov/refuge/Hagerman.

This post includes information from the post of December 2, 2010, by Dick Malnory.