Western grebe facts for kids
Quick facts for kids Western grebe |
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Aechmophorus
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| Species: |
occidentalis
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| Range of A. occidentalis Breeding range Year-round range Wintering range | |
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The western grebe (Aechmophorus occidentalis) is a type of grebe, which is a family of water birds. People sometimes call them "dabchick", "swan grebe", or "swan-necked grebe" because of their long necks.
Fossils of Western grebes have been found from a long time ago in North America. Scientists first thought they were a different species, but later realized they were just an older version of the grebes we see today.
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What They Look Like
The Western grebe is the biggest grebe in North America. It can be about 55 to 75 centimeters (22 to 30 inches) long. It weighs between 795 and 2000 grams (1.75 to 4.4 pounds). Its wings can spread out from 79 to 102 centimeters (31 to 40 inches).
These birds are black and white. They have a long, thin neck that looks like a swan's, and bright red eyes. It's easy to mix them up with Clark's grebe. Both birds look similar, are about the same size, act alike, and live in the same places. Sometimes, they even have hybrid babies together.
Western grebes build their nests in groups called colonies. They like lakes that have both marsh plants and open water. They make their nests from plants and wet materials. Both male and female grebes help build the nest, starting around late April to June. They keep adding to the nest even while laying eggs and sitting on them.
Western grebes live all over western North America. Clark's grebes usually live more in the southern parts of North America. There are a few ways to tell them apart. Western grebes have black feathers around their eyes and a straight, greenish-yellow beak. Clark's grebes have white feathers around their eyes and a beak that points up and is bright yellow. Young Western grebes are gray, while young Clark's grebes are white.
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A Western Grebe out of the water.
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A Western Grebe swimming.
Different Types of Grebes
In the past, scientists thought there were two main types of these grebes: one darker and one paler. They even found that these different types would live and breed together.
Today, we know that the darker and paler Western grebes are slightly different. They tend to mate with others that look like them. This means dark-faced grebes usually mate with other dark-faced grebes, and light-faced grebes mate with other light-faced ones. They also tend to stay close to their own type when nesting in colonies.
Breeding Habits
Western grebes build their nests in large groups on big inland lakes. Sometimes, they use marshes near the coast. These colonies can have hundreds of birds.
They have a very special courtship display to find a mate. Two birds will stand up on the water and run across the surface together. This is called the "Rushing Ceremony" or "water dance". It's the most common way they form a pair. Sometimes, two male grebes will do this dance to attract a female. When a female chooses one, the other male leaves. The winning male and female then perform the Rushing Ceremony together.
After the Rushing Ceremony, they often do the "Weed Ceremony". The pair bobs their heads in the water. Then, they dive down and come back up holding weeds in their beaks. They keep doing this until one bird drops its weeds and returns to normal.
They also have a "Greeting Ceremony" which involves dipping their heads, shaking their bills, and making sounds. These breeding dances are some of the most fancy dances among water birds.
After mating, the male Western grebe feeds his mate. This is like how parents feed their young. This feeding gives the female enough energy to lay her eggs. Both parents take turns sitting on the eggs to keep them warm. The parent who isn't incubating will go find food for the one on the nest.
How They Communicate
Western grebe parents use different sounds to talk to their young. One sound is called "ticking". This is an alarm signal. Parents carry their newborn chicks on their backs. When a parent ticks, the chicks know to hide their heads under the parent's back and stay quiet. If the chicks are older than four weeks, they will swim or dive away when they hear the ticking sound.
It's hard to tell which parent is making the ticking sound because they don't open their mouths. The parent carrying the chicks usually ticks more often. Both male and female parents tick equally.
Another sound is "clucking". This sound means "food". When a parent clucks, the young chicks will poke their heads out from their parent's back to get food.
Reproduction and Survival
The number of eggs a female lays can change as the breeding season goes on. If mating happens later in the season, fewer offspring might be produced. However, sometimes nests that hatch later in the season have more chicks. This might be due to things in their environment.
Young grebes can face tough conditions. Sometimes, older or stronger chicks might compete with younger ones, which can mean some don't survive.
Western grebes are very sensitive to humans. If people get too close to their nests, the parents might leave. This leaves their eggs unprotected and vulnerable to dangers. This shows that human activity can reduce how many young grebes survive.
The number of Western grebes has been slowly going down over the last 20 years. One big reason is oil spills. Because they are so sensitive, people are working to restore their natural homes. This helps them reproduce and raise their young safely.
What They Eat
Western grebes dive underwater to catch their food. They eat carp, herring, mollusks (like snails or clams), crabs, and amphibians like salamanders.
They often look under the water before they dive. Recent observations show that they might dive all the way to the bottom of the lake. They sometimes stab smaller fish with their beaks, like herons do. Other times, they just grab the fish. Most of the time, they swallow their food underwater. But sometimes, they bring it to the surface, squeeze it, and then swallow it.
See also
In Spanish: Achichilique occidental para niños
