This pair of Pied-billed Grebes offshore from Peter Jannink Park works constantly to improve their floating nest that will need to support them, their eggs, and two or more baby grebes within a few weeks. (© John G. Woods photo)

This pair of Pied-billed Grebes offshore from Peter Jannink Park works constantly to improve their floating nest that will need to support them, their eggs, and two or more baby grebes within a few weeks. (© John G. Woods photo)

Column: Grebes build their own life rafts in Salmon Arm Bay

Nature Watch by John G. Woods

As the water levels of Shuswap Lake reach ever-higher levels in late June, Pied-billed Grebes have been busy constructing floating rafts of marsh vegetation that will help keep their nests safe from flooding for the next month. Truly birds of the water, with little or no ability to walk on land and who rarely fly, it isn’t surprising that grebe home life is unlike most of our other shoreline birds.

In late June, working on a tip from one of the ‘regulars’ who stalk birds with a camera on the wharf, I was able to see my first Pied-billed Grebe nest in the emergent marsh grass offshore from Peter Jannink Park. Through my binoculars a suggestive lump in the grass resolved into an adult Pied-billed Grebe sitting on a seemingly flimsy mat of reeds. Without the adult bird, I likely would have overlooked the nest as just another bit of flotsam.

A convenient park bench proved to be an ideal place for me to watch the Pied-bill nest from a respectful distance. Almost immediately I saw another adult grebe make a V through the water to the nest, rummage around and then leave. A quick check to my pictures showed that this nest-mate was delivering additional marsh weeds to build up the nest. Then the swimming grebe made another underwater sortie and returned with second beak-full of ‘marsh bottom’. This went on for more than 30 minutes as I watched them. At one point, the delivery grebe dragged a long floating reed stalk to the nest and both parents worked on its installation.

Of course, it being nesting season, a tight-sitting bird is likely either laying an egg, or incubating eggs. I’d almost given up finding the answer when the sitting bird lifted up to help tuck in nesting material and I glimpsed two eggs beneath him or her (both sexes incubate eggs in grebes).

Read more: Column: Ravens signal spring in the Shuswap

Read more: Sharing insights from 50 years of counting birds in Salmon Arm

There are several benefits to building floating nests. The advantage of nesting on a raft that goes up and down with the water levels is obvious. Also, given that grebes can’t actually walk on land, a floating nest gives them an underwater escape hatch they can use to dodge an attacker from any direction.

Unlike many birds, Pied-bills start incubation when the first or second egg is laid. This means that by the time the clutch of about six eggs is complete, the babies in eggs one and two will be more developed and hatch earlier than their siblings from the later eggs.

As soon as they are able, young grebes scramble onto the backs of their parents where the adults serve as convenient, mobile, resting islands. As the young grow, baby grebes vie with each other for a position aboard. The burden of parenthood in the grebe world must sometimes be an extraordinarily overloaded task!

While Western Grebes are very easy to see this time of year, their tiny pied-billed cousins are more of a challenge to find. Pied-bills are much smaller, and as their name suggests, have two-toned bills: white with a black band. And unlike Western Grebes, Pied-bills aren’t showy—they often lurk with just their heads above water as they assess their surroundings.

Salmon Arm Bay is an extraordinarily good place to look for both Western and Pied-billed Grebes but our complete grebe checklist includes Clark’s, Red-necked, Eared and Horned. As usual, both the wharf and Peter Jannink Park are top viewing locations.


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