The western grebe, scientific name Aechmophorus occidentalis is a species within the grebe family of water birds. Folks names embody “dabchick”, “swan grebe” and “swan-necked grebe”. In this article, I am going to discuss western grebe dance, call, courtship, mating, habitat, chicks, range, baby, etc.
Western Grebe profile
Western grebe fossils from the Late Pleistocene of southwest North America have been described as a definite species, however, later ranked as a paleosubspecies Aechmophorus occidentalis lucasi.
Newer research discovered them to fall throughout the variation now recognized to exist in at the moment's birds.
Western grebe Description
The western grebe is the most important North American grebe. It's 55-75 cm (22-30 in) lengthy, weighs 795-2,000 g (1.753-4.409 lb) and measures 79-102 cm (31-40 in) throughout the wings.
It's black-and-white, with an extended, slender, swan-like neck and pink eyes. It's simply confused with Clark's grebe, which shares related options, physique measurement, habits and habitat, and hybrids are recognized.
Western grebes nest in colonies on lakes which are combined with marsh vegetation and open water.
Western Grebe nests are made from plant particles and sodden supplies, and the nest-building begins roughly around late April by June.
The development is finished by each sex and is sustained on all through laying and incubation.
This species of waterbirds is widespread in western North America, so there isn't any particular place of abundance.
Its subspecies, Clark's grebe typically populate extra of the southern a part of North America.
Different variations are whiter flanks and paler grey backs when evaluating A.o.clarkii to A.o.occidentalis.
The western grebe has black across the eyes and a straight greenish-yellow bill whereas Clark's grebe has white across the eyes and an up-turned shiny yellow bill.
The downy younger of Western are gray; Clark's downy younger are white.
Western Grebes are crisp black and white, with a pointy transition between black and white extending down the neck.
The pinnacle and a lot of the face are black, with white beneath the attention. The bill is yellowish or greenish-yellow and the attention is pink at shut vary.
Dimension & Form
A big, slender waterbird with a really lengthy neck, a big head which will present a peak, and an extended, slender, pointed bill.
Breeding birds use freshwater lakes; nonbreeding birds are present in each freshwater and saltwater environments, although by no means removed from shore in oceans.
Western grebes nest in colonies of tons of on massive inland lakes, typically utilizing coastal marshes, in western North America.
It has a spectacular courtship show; two birds will rear up and patter throughout the water's floor.
Northern birds migrate west to the coastal ocean in winter; birds within the southwest and Mexico could also be everlasting residents.
In the course of the breeding season, the birds promote themselves by ceremonies.
Dashing Ceremony, which will be additionally referred to as water dance, race, or run, is a ceremony that's the most frequent show to type a pair-bond.
That is carried out in pairs of both male Western grebes or one male and one feminine.
One in all two people initiates Dashing, and the paired particular person follows instantly and performs in synchrony.
The birds carry their wings stiffly to the facet and run in an upright place with its head held ahead and neck curved.
The males appear to carry out the dashing collectively to draw the eye of females, and when considered one of two males attracts a feminine from his dashing habits, a contest arises between males to get the feminine.
One out of two withdraws and the “successful” male mates with the feminine by performing Dashing collectively and proceed to carry out Weed Ceremony.
Weed Ceremony normally precedes the acts of mating and nest construction. It's carried out after the pair is shaped, and the ceremony begins because the mates bob their heads in the water.
Then they dive in place and are available again as much as floor whereas holding weed on their beaks.
This ceremony is sustained until one of many pair flips away its weeds and drops to a standard place in water.
They proceed with their mating with Greeting Ceremony. Greeting ceremony is just like the type of dashing ceremony and entails dip-shaking, bob-shaking, bob-preening, and arch-clucking.
Dip-shaking consists of dipping the top within the water and elevating it up whereas quickly waggling the bill facet to facet.
This entails a low neck posture and conspicuous water splash whereas bob-shaking doesn't. These breeding dances are recognized to be probably the most elaborated dances within the waterbird species.
After breeding, the male Western Grebes feed their mate, thus performing mate feeding habits.
The feeding resembles the feeding of the younger by mother and father, and thru the feeding they receive, females are capable of have sufficient vitality to type their eggs.
Throughout the incubation interval, female and male Western Grebes commerce locations to incubate their eggs for weeks, and people that aren't incubating feed their mate.
When tending their younger, Western grebe mother and father use various kinds of vocalization to speak.
Ticking is likely one of the two and is used as an alarm sign.
Mother and father carry their newly hatched younger on their backs, and when the mother and father make a ticking sound, that is used as a sign for his or her chicks to cover their heads beneath the again of their mother and father and be silent.
If chicks are larger than Four weeks of age, they reply to the ticking by swimming or diving away on their very own.
When making a ticking sound, the callers don't open their mouths, so it's laborious to tell apart who's the maker of the sound.
The guardian who carries the chicks are inclined to make the ticking sound extra typically than these that don't, and each of the female and male mother and father are equally more likely to tick.
One other vocalization noise is clucking, and these alerts for meals.
When a guardian clucks, the younger reply to it by poking their head out of their guardian again the place they're on to obtain meals.
Western grebe Habitat
Rushy lakes sloughs; in winter, bays, ocean. Summers primarily on recent water lakes with massive areas of each open water and marsh vegetation; not often on tidal marshes.
Winters primarily on sheltered bays or estuaries on the coast, additionally on massive recent water lakes, not often on rivers.
Western Grebes are extremely gregarious in any respect seasons, nesting in colonies and wintering in flocks.
Their skinny, reedy calls are attribute sounds of western marshes in the summer season.
Reproduction and survival
The clutch measurement decreases because the mating season progresses, which means if the mating is finished on the final of days in mating season, the quantity of offsprings which are produced is smaller.
Nonetheless, additionally, it is acknowledged broods measurement from the nest that hatched later within the season is bigger than these from earlier, which contradicts earlier discovering.
This can be because of ecological constraints.
Ecological constraints additionally stress the younger, and this will result in siblicide within the first weeks of the hatching, which can clarify the brooding variations.
Additionally, the Western grebes are delicate to people, so when there are any human disturbances current close to them, the mother and father would go away their nest, thus leaving their unhatched eggs to be susceptible to assaults.
This exhibits the predation and even the seemingly threatening acts end in a lower copy and survival of the younger.
Additionally, as a result of they're so delicate, there have been restoration efforts to rebuild the Western grebes' native lands, in order that they can reproduce and lift their younger with no threats inflicted on them.
Not solely by the predation menace, the variety of the Grebes has been slowly declining within the final twenty years, with oil spillage being one of many main causes.
Western grebe Behavior
Western Grebes are near all the time within the water, the place they dive for prey or relaxation on the floor.
They'll disappear for lengthy intervals throughout dives.
Courting birds have a fascinating show wherein the pair races facet by facet throughout the water, their necks gracefully curved and payments pointed to the sky.
Western grebe Eggs
2-4, not often 1-6. Pale bluish-white, changing into nest-stained brown. Incubation by each sex, about 24 days.
Hatching not synchronized; the final egg could also be deserted in the nest.
Younger: Climb onto again of guardian inside minutes after hatching, quickly go away nest; are fed by each mother and father.
The patch of naked yellow pores and skin on the head of younger turns scarlet when younger beg for meals or are separated from mother and father.
Age at first flight about 10 weeks. One brood per yr.
Western grebe Baby
Climb onto again of guardian inside minutes after hatching, quickly go away nest; are fed by each mother and father.
patch of naked yellow pores and skin on the head of younger turns scarlet when younger beg for meals or are separated from mother and father.
Age at first flight about 10 weeks. One brood per yr.
Western grebe Nesting
Breeds in colonies. Courtship shows elaborate and sophisticated.
Most conspicuous is a show wherein two (or extra) irds rear as much as upright posture and rush throughout the floor of water facet by facet, with the loud pattering of toes, diving underwater at the finish of rush; different shows embody “dancing” on the water with bits of weed held in the bill.
Nest: Site is in shallow water marsh. Nest (constructed by each sex) a floating heap of plant materials, anchored to standing vegetation.
Meals and feeding
This hen dives for carp, herring, mollusks, crabs, and amphibians, equivalent to salamanders. It typically friends beneath the water earlier than diving.
The latest observations recommend that the grebe dives on the backside of the lake.
Some smaller fish are impaled very similar to herons, with the bill, however, others are grasped. Most are swallowed underwater, however, some are delivered to the floor, pinched, and swallowed.
Forages by diving from the floor and swimming underwater propelled primarily by toes.
Western and Clark's are solely grebes having construction in neck permitting speedy spear-like thrusting of the bill; could also be helpful in spearing fish, however, use of these habits just isn't well-known.
Round starting of the 20th century, tens of 1000's have been killed for his or her feathers. Obvious restoration since, and has begun breeding in new areas not occupied traditionally.
Mexican populations of each Western and Clark's grebes could also be declining as chopping of tules on lakes removes nesting habitat.
Western grebe Migration
Migrates in the night, in all probability in flocks. Most birds from northern a part of vary migrate west to Pacific Coast.
Some southwestern and Mexican populations in all probability everlasting residents.
Western grebe facts
Western and Clark's Grebes have been thought-about the identical species till 1985 after scientists realized that the 2 species not often interbreed (regardless of typically residing on the identical lakes), make completely different calls, and have substantial DNA variations.
Male Western Grebes typically have longer and thicker payments than females.
The distinction could allow women and men to feed on different-sized prey, lowering meal competitors between the sexes.
Western Grebe plumage could be very dense and waterproof.
Within the nineteenth century, the birds have been hunted and their hides used to make coats, capes, and hats that price as a lot as luxurious objects created from mammal pelts.
In some areas, grebe populations crashed and even disappeared altogether. In time, the clothes went out of trend, sparing this species (and Clark's Grebe) additional losses.
Western Grebes, together with different grebe species, typically swallow their very own feathers as they preen.
These feathers wind up lining the abdomen, the place they could assist defend towards punctures by sharp fish bones.
They periodically regurgitate pellets containing the feathers together with bones and different indigestible materials.
The oldest recorded Western Grebe was a female and no less than 11 years outdated when she was present in Minnesota, the place she had been banded.