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.ApprovedCurrent stage of this record in the editorial review workflow. Recent Sighting
Thalasseus maximus
Royal Tern
Boddaert, 1783
Detailed Texts Multi-lang
Large tern with a robust, bright orange bill and a shaggy black crest on the back of the head.
Added by
Anonymous Curator
Reviewed by
Julia Trouin
Last modified by
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).Charadriiformes
FamilyRank below Order. Groups closely related genera (e.g., Felidae = cats, Canidae = dogs).Laridae
GenusRank just above Species. The first word in the two-part binomial scientific name.Thalasseus
Taxonomic AuthorityThe scientist who first formally described and published this species, followed by the year of publication.Boddaert, 1783
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.
Stable
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
Marine coasts, estuaries, and bays; rarely found inland except on large coastal lakes.BehaviourDaily activity patterns, movement, territory use, foraging style, and seasonal behavioral changes. Multi-lang
Very noisy colonial bird during breeding season.Social ActivitySocial structure: whether the species is solitary, paired, or colonial; hierarchy and communication. Multi-lang
Very social, lives in flocks and forms dense colonies.Feeding GuildWhat the species eats, how it forages or hunts, and its role as a consumer in the food web. Multi-lang
Aerial hunter that uses sight to locate prey below the surface.Trophic Chain DetailsSpecific interactions in local food webs: prey species, predators, competitors, and scavengers. Multi-lang
Piscivorous, feeds mainly on small marine fish.Reproductive BehaviourMating strategies, courtship displays, nesting or spawning behavior, and parental care. Multi-lang
Nests on the ground, in open colonies.Physical Measures
Length (cm)
45.0 - 50.0 cm
Weight (Grams)
350 g - 500 g
Offspring per cycleTypical number of young (live births, eggs, or seeds) produced by one adult in a single reproductive event or breeding season.1 - 2
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.
3 - 4 Years
Gestation / IncubationDuration from fertilization to birth (mammals) or to hatching (egg-laying species).
25 - 30
Lifespan EstimatedExpected duration of life from birth to natural death under wild conditions.
Males15 - 20 Years
Females15 - 20 Years
Evolutionary AdaptationsInherited traits and behaviors that improve the species' survival and reproduction in its specific environment. Multi-lang
Specialized bill: Its strong and sharp structure allows it to accurately capture relatively large fish in the air or underwater.
Main ThreatsDocumented pressures reducing the population: habitat loss, hunting, disease, climate change, and invasive species. Multi-lang
Disturbances in nesting colonies, loss of fishing grounds, and predation by introduced species.
Interesting FactsSurprising or notable facts that highlight what makes this species unique or ecologically important. Multi-lang
They usually fish by shallow diving, plunging into the water from a considerable height.