AnimaliaHighest rank in taxonomy. Groups all life into domains: Animalia, Plantae, Fungi, etc.IUCN LCInternational Union for Conservation of Nature — the world authority on species extinction risk, using standardized criteria. — Least Concern — widespread and abundant; not at immediate risk of extinction.In ProgressCurrent stage of this record in the editorial review workflow. Recent Sighting
Podiceps nigricollis
Eared Grebe
Brehm, CL, 1831
Detailed Texts Multi-lang
A small, elegant waterbird with a distinctive thin, upturned black bill and a steep, peaked forehead. In breeding plumage, adults exhibit a striking black head, neck, and back, accented by radiant fan-like golden-yellow plumes extending behind the rich red eyes, and warm chestnut-rufous flanks. In non-breeding plumage, it transforms into a muted slate-grey and white bird with a dusky cheek patch.
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Julia Trouin
TaxonomyBiological classification ranks placing this species within the tree of life, from Kingdom down to Genus.
PhylumRank below Kingdom. Groups organisms sharing a fundamental body plan (e.g., Chordata = vertebrates and some invertebrates).Chordata
ClassRank below Phylum. Subdivides by structural traits (e.g., Mammalia, Aves, Reptilia, Insecta).Aves
OrderRank below Class. Groups related families sharing common ancestry (e.g., Carnivora, Primates).Podicipediformes
FamilyRank below Order. Groups closely related genera (e.g., Felidae = cats, Canidae = dogs).Podicipedidae
GenusRank just above Species. The first word in the two-part binomial scientific name.Podiceps
Taxonomic AuthorityThe scientist who first formally described and published this species, followed by the year of publication.Brehm, CL, 1831
Record Completeness
95%Coming soon
Ecology & StatusHow this species lives: habitat preferences, diet, behavior, population status, and role in its ecosystem.
OriginWhether the species is native (evolved here), endemic (found only here), or introduced by human activity.
Native
Population TrendDirection of change in population size over time: increasing, stable, decreasing, or unknown.
Decreasing
Breeding SeasonTime of year when this species typically reproduces or flowers.
Year Round
Trophic RolePosition in the food chain: producer, herbivore, carnivore, omnivore, decomposer, or parasite.
Carnivore
Recent SightingsWhether this species has been observed in the wild in Costa Rica within recent years.
Yes
Habitat SummaryOverview of the specific ecosystems and environments where this species is found in Costa Rica. Multi-lang
Breeds on shallow, highly productive freshwater lakes, marshes, and large ponds rich in emergent vegetation. During the non-breeding and molting seasons, it migrates massoversy to hypersaline lakes and coastal estuaries, forming immense aggregations.BehaviourDaily activity patterns, movement, territory use, foraging style, and seasonal behavioral changes. Multi-lang
An expert diver that spends almost its entire life on the water, being virtually incapable of walking on land due to its anatomy. It takes off from water only after a long, frantic running patter on the surface. Its vocalization during breeding is a clear, rising, melancholic whistling series: 'poo-ee-chk' or a soft corporate chattering.Social ActivitySocial structure: whether the species is solitary, paired, or colonial; hierarchy and communication. Multi-lang
Highly gregarious, nesting in dense, packed colonies that can number hundreds of pairs. During migration and wintering, it exhibits exceptional social clustering, forming synchronized feeding flocks of tens of thousands of individuals blanketing the water.Feeding GuildWhat the species eats, how it forages or hunts, and its role as a consumer in the food web. Multi-lang
Aquatic pursuit diver.Trophic Chain DetailsSpecific interactions in local food webs: prey species, predators, competitors, and scavengers. Multi-lang
Strictly carnivorous aquatic forager. Its diet is dominated by aquatic insects (notonectids, dragonflies), larvae, brine shrimp, and small crustaceans, along with tiny small fish. It routinely swallows its own feathers to form a protective stomach lining that holds sharp fish bones. Predators include gulls, minks, large pike, and eagles.Reproductive BehaviourMating strategies, courtship displays, nesting or spawning behavior, and parental care. Multi-lang
Monogamous pairs engage in highly complex, choreographed courtship displays including head-shaking and the 'penguin dance' where they rise vertically out of the water holding weeds. They construct a floating nest platform composed of sodden aquatic vegetation, anchored to emergent reeds. The female lays 3 to 4 chalky-white eggs that quickly stain brown.Physical Measures
Length (cm)
28.0 - 35.0 cm
Weight (Grams)
250 g - 450 g
Offspring per cycleTypical number of young (live births, eggs, or seeds) produced by one adult in a single reproductive event or breeding season.3 - 5
Sexual DimorphismObservable physical differences between males and females of the same species (e.g., size, coloration, features).No
Lifespan
Sexual MaturityAge at which the individual becomes capable of reproducing for the first time.
11 - 12 Months
Gestation / IncubationDuration from fertilization to birth (mammals) or to hatching (egg-laying species).
20 - 22
Lifespan EstimatedExpected duration of life from birth to natural death under wild conditions.
Males5 - 10 Years
Females5 - 10 Years
Evolutionary AdaptationsInherited traits and behaviors that improve the species' survival and reproduction in its specific environment. Multi-lang
Salt glands located above the eyes that are highly developed, allowing the bird to excrete excess salt and comfortably exploit extreme hypersaline lakes rich in brine shrimp during long staging periods.
Lobed toes instead of webbed feet, positioning its strong legs far back on the body to generate immense hydro-propulsive thrust for precise underwater pursuit diving.
Main ThreatsDocumented pressures reducing the population: habitat loss, hunting, disease, climate change, and invasive species. Multi-lang
Vulnerability to large-scale ecological die-offs due to pollution, chemical spills, and climate-induced water diversions at critical migratory bottleneck locations like Great Salt Lake or Mono Lake.
Interesting FactsSurprising or notable facts that highlight what makes this species unique or ecologically important. Multi-lang
This bird undergoes an extraordinary flightless period during molt where its flight muscles atrophy and digestive organs double in size to accumulate huge fat stores, reverting the process before migrating.