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It's Time to Talk Grebes!!!

Thanks to James Smith for the Writeup and Photos

Summer With The Grebes

by James Smith

The year 2020 started out bad, and then got worse.  But during the pandemic slow down, when my work was cut back, I started spending more time driving over to the Sacramento National Wildlife Refuge at Willows.  As luck would have it, this turned out to be a special year at the refuge.  A group of Clark’s and Western Grebes decided to build their nests right next to the auto tour road, unlike in past years when they built them way in the back.  So having them so close was a special treat, where I could take my camera and temporarily escape the insanity for a couple days each week, to experience the entire breeding season out my vehicle window.

Clark’s and Western Grebes are really interesting birds, and both nest on the pond at SNWR during the summer.  They are similar, with the Western having black around the eye, while the Clark’s has white, and differing slightly in their call, so I’ll be referring to them collectively as the grebes.  The most famous thing you may have heard about these grebes is their mating ritual which includes the “rushing” ceremony, where they run across the water side by side.  This occurs in the spring, at the end of May and into the first part of June.  Here’s a tip: just before they take off rushing, the grebes will be facing off with their heads down on the water.  After the rushing ceremony comes the weed ceremony, where they slip off to a quiet corner of the pond, stretch their necks way up, snuggle close, and smack each other in the face with a wad of soggy weeds.

The first thing to notice when observing these large grebes is that they don’t particularly like to fly.  During the past three years of observing them I have yet to see one flying.  Instead, they prefer to swim if threatened, and they can swim very fast.  Their legs are attached further back on their bodies with big lobed feet.  They use their feet like an outboard motor to skim across the water at high speed, sometimes holding their wings out as stabilizers.  They can also swim fairly fast underwater as well, and can attack from below like a pointy torpedo.  And lastly, they can run on water without flapping their wings.  There are two times when they do this, during the mating “rushing” ceremony, and sometimes when they charge another bird that gets too close to the nest.  When charging another bird, there are two postures a grebe may use: the standard torpedo swimming posture, or what I call the “jousting” posture.  The jousting posture is when the grebe starts running across the water at the opponent with its head held low to the water.  I haven’t seen that mentioned anywhere before; but I saw the grebes do it on several occasions, and it looks really cool when photographed.  After initially charging at the offender, they will then drop into the faster swimming posture.  In most cases, the offender would immediately zoom away when charged; but occasionally, a challenging grebe will stand its ground and fight.

The nesting season extends from May to October.  Both partners help in constructing a floating nest platform.  As soon as it is large enough to stand on, the first egg will be laid.  The eggs are initially white, and then later turn brown, being stained by the rotting vegetation in the nest.  Most grebes lay three eggs, usually a day or two apart, and they usually hatch in about 24 days.  Most of the nesting pairs will start early and build their own nest; but some will start later and take over an abandoned nest, or try to steal a nest from another pair.  Once the chicks are hatched, they climb onto the back of a parent and ride around, and that’s when all the cute photographs are taken, and a line of vehicles will show up at the refuge. 

This summer, I was fortunate enough to be at the refuge on three days when an egg was hatching.  A newly hatched chick has a wet-headed purplish-pink appearance.  So if you see a purplish chick at the back of a parent, you know that it just crawled out of its egg.  It will then climb up onto the parent’s back and stay hidden under the wing for awhile drying off, before popping up its now fluffy light gray head to be fed.  The hatching sequence takes about 20 to 30 minutes.  One particularly cool thing about grebe chicks is the spot on their forehead.  According to the biologists, this bare pink spot on the forehead will get darker red when the chick is hungry or stressed, and will fade when the chick has been fed.  So it is nature’s own “low-battery” indicator!

The young chicks will stay hidden under the parent’s wing a lot of the time, so you may have to look carefully to detect when a grebe has a young chick.  Look at the way the wings are folded over the back.  If the wings are folded tight, then no chick; but if some of the feathers are fluffed up a little, then they probably have a chick underneath.  If you watch and wait, eventually the chick will pop its head up, especially when a parent has a yummy fish or bug to feed them.  Grebe parents will also trade off chick carrying duty.  Since they don’t have hands to pass them over, they simply rear up and shake or flap their wings to make the chick slide off their back into the water, like a big water slide.  The parent that shook them off may then point at them or swim away, while the other parent fluffs up its wings and holds out its foot to invite them up.

Another interesting behavior I got to witness was pair bonding.  Grebes will, of course, do the wild thing prior to laying the eggs; but what I didn’t know, and what the biologist at SWNR later told me, is that grebes will also sometimes engage in pair bonding later during the nesting cycle.  Pair bonding is when they make cooing goo-goo eyes at each other and then the male hops up and stands on the female’s back for a few seconds before jumping off forward over her head.  What was really unexpected, is that I saw a pair do this when the female had two chicks on her back, and the third egg was in the process of hatching underneath her.  It seemed like an odd time to be getting frisky!

Everything is not all unicorns and rainbows for grebes living in a refuge, however.  They have to live with a number of predators, such as coyotes, foxes, raccoons, river otters, feral cats and dogs, eagles, great horned owls, and hawks.  The night is long when you are a grebe sitting on a nest near the edge of the pond.  There is also a risk with just leaving the nest for a short time, as gulls, terns, or coots will go after unguarded eggs.  Sometimes a grebe will lose its partner, say to a great horned owl, and after a couple days of calling for it, will have to abandon the nest to feed itself.  This happened on at least one nest this summer.  There were also a couple of nests close to the edge of the pond that were raided early in summer, and the grebes had to lay new eggs and try again.  After hatching, the young chicks will also be the target of hungry predators; but are better protected riding on a parent’s back than being left alone in a nest.

The grebes are afraid of otters.  If one approaches, they will jump off the nest.  I got to witness an otter incident one day in late July, while I was sitting in my car watching the nest.  The grebe mother had all three chicks on her back, and was in the water near the nest.  Suddenly, all the grebes in the area went on high alert.  The female immediately began swimming west, away from the nest, while the male stayed floating nearby.  A few seconds later an otter did a porpoise breath a couple meters to the right of the nest and disappeared.  About thirty seconds later, it popped up right in front of me at the east edge of the pond for a split second, and then a few seconds later it popped its head up again down the shore to the left of me.  The female, in the meantime, swam all the way out to the middle of the pond, just a speck in the distance.  Then it was quiet for about fifteen minutes, before the male suddenly gave a loud call.  The female then started swimming back from the middle of the pond.  When she returned, they both resumed swimming and feeding the chicks near the nest as before, as if nothing had happened.

I was sorry to see September bring an end to the summer, and I know I was lucky to be able to visit when others could not.  Hopefully, the grebes will nest close to the road again next year and everyone will be able to enjoy the grebe experience at SNWR.