I had done my homework before releasing a Western Grebe from the wildlife rehabilitation center. “Western Grebes are incapable of walking on land,” due to how far back their legs are set on their bodies. Even the ultimate resource, the Sibley Guide to Birds, agreed. I’d need to wade a few feet into the reservoir so the bird could swim out of the transport crate. About 10 feet from the water’s edge, I stopped to open the crate door so the bird wouldn’t be trapped if it became agitated as it sensed the water. After one quick look through the open door, though, the grebe bolted. Well, kind of tiptoed/scrambled across the beach to the water. It wasn’t pretty. It wasn’t graceful. But it was definitely a version of walking. Um—Mr. Sibley? (Now, years later, you can find videos of this behavior on the Internet. And the new edition of the Sibley Guide no longer contains that text.)
An adult Western Grebe is a large black-and-white water bird distinguished by a long, thin, swan-like neck and a greenish yellow, massive, straight spike for a bill. (Males and females have similar plumage.) Dark above and bright white below, a Western has a black cap that streams down the back of its neck like a dark mane. From afar, the best field mark for distinguishing a Western from its former conspecific and nearly identical Clark’s Grebe is the Western’s drab, greenish yellow bill contrasted to the bright orange-yellow bill of a Clark’s. If at a distance you can’t decide what color the bill is, odds are you’re looking at a Western. With good optics and bright light, you can also see that the black cap of a Western completely surrounds its dark eye; a Clark’s eye lies distinctly below its cap.
In the mid-20th century, Western Grebes were just winter visitors to San Diego County. They arrived from the north in October and November and departed mainly in April. Since the 1950s, though, they have also become locally common summer breeders, colonizing an increasing number of lakes and lagoons surrounded by marshes.
Western Grebes eat fish, fish, and more fish, primarily pursued under water using their powerful, set-far-back legs. They will also take crustaceans and bottom-dwelling fish, suggesting that they forage along the bottom as well. Western and Clark’s Grebes are unique among grebes in their ability to thrust their bills forward like a spear.
Along those lines, this extraordinary bill plays a role in the Western Grebe’s scientific name, Aechmophorus occidentalis. The genus name arises from the Greek aikhmophoros (“one who carries a spear”). The species name (occidentalis) derives from Latin for “western,” reflecting the bird’s natural range in the western U.S. (as does the common name). “Grebe,” from French (grèbe), refers to a crest of feathers on a bird’s head, found in some European grebe species.
Western Grebes are perhaps best known for their elaborate and energetic courtship ritual: a series of displays in pairs including running across the water side by side (https://lakehodgesphototours.com/video-gallery/). Often found in colonies of hundreds or even thousands on a lake, nests rarely lie more than 6 feet apart. The parents use aquatic vegetation to build a nest on a submerged snag or anchored to emergent or floating plants. Clutch size ranges from 3−7 eggs; incubation lasts 24 days. Within minutes of hatching, the young climb onto a parent’s back, riding there while the adults swim and forage. At the end of a brooding bout, the parent rises up in the water and flaps its wings; the young drop off and paddle to the other parent. Adults may assist youngsters in climbing back up by holding one foot stiffly out on the surface, providing a literal “leg up.” Although back-brooding lasts only about four weeks, the young often stay with their parents until migration. If a nest is lost, the pair commonly renests, although a pair usually raises only one brood per season.
That last point is an important one. In San Diego County, Lake Hodges hosts vast flocks of Western and Clark’s Grebes throughout the winter and into breeding season. In 2019, water levels there suddenly dropped at the end of March, resulting in the abandonment of as many as 300 grebe eggs—many likely within days of hatching—because adult birds could no longer climb into the nests. The birds might have recovered through renesting quickly except that the water levels dropped again in late April. Part of the problem arose from the complex relationship among the city of San Diego, the County Water Authority, and San Diego Gas & Electric, all of which have some regulatory authority over the management of the lake’s water level. The California Department of Fish and Wildlife convened a meeting of stakeholders, seeking better coordination of water management to avoid destroying nests, including installing artificial floating nest platforms and specific pumping schedules that don’t interfere with the grebes’ nesting. Success this year will be determined in the coming months. Stay tuned.
Western Grebes may not be elegant when trying to walk on land. But you definitely should see them “walk on water.” Which you can do if you head to Lake Hodges before the end of January, when this impressive courtship behavior begins to diminish.
Photo Credit: Mike’s Birds 2016