Gruidae

Supported crane assignment

Record the observed trait combination and competing identifications without treating one suggestive trait as decisive.

1. Which observed flight posture, plumage, head features or calls support Gruidae? definition
2. Which heron, stork or other local lookalike remains plausible, and what observation would distinguish it? boundary

Traceable identification

Tie species and individual assignments to dated evidence, accounting for immature plumage and uncertain flock membership.

1. Which taxonomic reference and diagnostic evidence support the species assignment? provenance
2. Does this record concern a recognisable individual, a mixed-species flock or a defined population, and how is that established? boundary

Functional condition

Distinguish observed difficulty from an activity that was simply not seen.

1. Can the crane stand, walk, use both wings and obtain food, and which functions were actually observed? measurement
2. Could age, resting behaviour or a documented moult state explain apparent flightlessness? boundary

Condition change and care context

Keep wild, managed and captive contexts explicit when interpreting body condition or abnormal behaviour.

1. What repeat observations or legitimate measurements show improvement, deterioration or stable condition? measurement
2. Is the crane free-living, provisioned, captive or recently released, and which records establish that context? provenance

Pair and family evidence

Treat pairing, parentage and juvenile dependency as evidence-based assignments.

1. What repeated association, coordinated calling or care behaviour supports a pair or family relationship? provenance
2. Could the apparent pair or family instead be birds temporarily sharing a feeding or roosting site? boundary

Breeding stage and outcome

Separate observed eggs, hatchlings, surviving young and fledged young, retaining unknown outcomes.

1. Which observations establish the current breeding stage and numbers of eggs or young? measurement
2. How can the next stage or outcome be checked without approaching the nest or separating the family? action

Site function and suitability

Evaluate wetland, grassland, agricultural and tree-roosting use where appropriate to the identified cranes.

1. Is this site used for nesting, feeding, roosting or several functions, and in which season? definition
2. Which measured water conditions, food resources, vegetation or roost structures support the observed use? measurement

Seasonal dependence and counts

Interpret crane arrivals, departures and counts in relation to survey coverage and links between sites.

1. What repeated sightings, marked-bird records or tracking evidence connect this site to other seasonal locations? provenance
2. Could a count change reflect redistribution, migration timing, double counting or survey effort rather than population change? boundary

Crane-specific risk evidence

Connect threats to observed flight routes, feeding areas, roosts, nests or affected birds.

1. Which hazard overlaps documented crane activity, and what evidence shows exposure or harm? provenance
2. What changes in feeding, vigilance, displacement, injury or breeding outcome can be measured without assuming causation? measurement

Permitted and evaluable action

Compare observation, disturbance reduction, habitat measures and specialist intervention against the crane's condition and dependencies.

1. Which action is justified, and what species identification, local authority, permissions and specialist competence must be established before it proceeds? action
2. What outcome and stopping criteria will show whether the action helps without separating dependent young or displacing cranes from essential sites? action

Kinds and varieties

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• Crowned cranes (Balearica regulorum and B. pavonina), the African tree-perching pair with a bristled nuchal crest
• Siberian crane (Leucogeranus leucogeranus)
• Sandhill crane (Antigone canadensis), including hunted continental populations and listed isolates such as the Mississippi and Cuban subspecies
• Other Antigone cranes: sarus, brolga and white-naped
• Demoiselle and blue cranes (former Anthropoides, now usually placed in Grus)
• Wattled crane (former Bugeranus carunculatus)
• Typical northern Grus: Eurasian, hooded, whooping, black-necked and red-crowned cranes

1. Which of these kinds and varieties hold for the sense of Gruidae this model covers, and on what evidence? provenance

Identifiers and schemes

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• Wikidata - Q25316 - Item for family Gruidae.
• ITIS TSN - 176175 - Integrated Taxonomic Information System taxonomic serial number for Gruidae.
• NCBI Taxonomy - 9105 - NCBI taxid for family Gruidae.
• ICZN scientific name - Gruidae Vigors, 1825 - Family-group name; species written as binomials under the four living genera.
• IOC World Bird List - family Gruidae (15 species) - Checklist used by many ornithological databases; genus placement of Anthropoides and Bugeranus differs on some other lists.

1. Which of these identifiers and schemes hold for the sense of Gruidae this model covers, and on what evidence? provenance

Standards and regulation

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• CITES Appendices I and II (CITES Secretariat) - most crane species are listed; several (e.g. whooping, Siberian, red-crowned) on Appendix I
• Convention on the Conservation of Migratory Species of Wild Animals (CMS), including the Memorandum of Understanding concerning Conservation Measures for the Siberian Crane
• U.S. Endangered Species Act (U.S. Fish and Wildlife Service) - whooping crane (Grus americana) and listed sandhill subspecies
• Migratory Bird Treaty Act (United States) and counterpart migratory-bird conventions with Canada, Mexico, Japan and Russia
• Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA, under UNEP) for relevant African-Eurasian populations
• Ramsar Convention on Wetlands - not a taxon statute, but the principal habitat instrument for crane staging and breeding sites

1. Which of these standards and regulation hold for the sense of Gruidae this model covers, and on what evidence? provenance

Real-world use

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• Managed sport harvest of sandhill cranes in parts of the United States, Canada and Mexico under flyway frameworks
• Flagship wetland conservation, including captive breeding and reintroduction of the whooping crane
• Seasonal wildlife tourism at staging and winter roosts (Platte River in Nebraska; Izumi in Kagoshima; Hortobágy; Hula Valley)
• Grain and sprouting-cereal depredation, which drives both compensation schemes and local persecution
• National and heraldic symbols (grey crowned crane of Uganda; blue crane of South Africa; red-crowned crane in Japan and East Asia)
• Zoo, aviary and International Crane Foundation studbook programmes

1. Which of these real-world use hold for the sense of Gruidae this model covers, and on what evidence? provenance

Typical measurements

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• Standing height - 90-180 - cm
• Wingspan - 150-250 - cm
• Body mass - 2-12 - kg
• Clutch size - 1-3 (typically 2) - eggs
• Incubation period - 28-36 - days
• Wild longevity - 20-40 - years

1. Which of these typical measurements hold for the sense of Gruidae this model covers, and on what evidence? provenance

Failure modes and hazards

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• Drainage, conversion and drying of breeding, staging and winter wetlands
• Collision with overhead power lines and wind turbines at traditional flyways and roosts
• Illegal shooting; historical market hunting that reduced the whooping crane to a few tens of birds
• Lead poisoning from ingested spent shot used as grit
• Demographic and genetic bottleneck in the whooping crane
• Highly pathogenic avian influenza and other epizootics at dense roosts, including crane herpesvirus (inclusion body disease)
• Human disturbance at nests and night roosts; nest predation in fragmented habitat
• Persecution and poisoning where cranes damage crops

1. Which of these failure modes and hazards hold for the sense of Gruidae this model covers, and on what evidence? provenance

Regional variation

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• In some English dialects 'crane' is still used for herons; the birds are not Gruidae
• Sandhill cranes are a managed game species in parts of North America; almost all other living Gruidae are fully protected
• East Asian wintering concentrations (China, the Korean Peninsula, Izumi) hold several threatened species under different national laws and cultural protection
• African crowned cranes are far more often kept and traded as ornamental birds than typical Gruinae
• Checklist practice differs: IOC/Clements place demoiselle, blue and wattled cranes in Grus and split Antigone; some regional lists retain Anthropoides and Bugeranus

1. Which of these regional variation hold for the sense of Gruidae this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

• Herons and egrets (Ardeidae) - Cranes fly with the neck fully extended; herons retract it into an S-curve. Cranes also lack powder down and a spear-strike hunting posture.
• Storks (Ciconiidae) - Storks lack the coiled tracheal loop and bugling unison call, more often travel by soaring, and differ in bill shape and bare-part pattern.
• Limpkin (Aramidae) - Sister family to Gruidae; a much smaller, spotted marsh bird with a decurved ibis-like bill, not a crane silhouette or bugle.
• Rails and coots (Rallidae) - Historically the same order Gruiformes, but small, short-necked wetland birds without crane flight profile or unison calling.
• Great blue heron versus sandhill crane - Sandhill is bulkier, flies with neck out and legs trailing in a straight line, and gives a rattling bugle rather than a croak.
• Whooping crane versus American white pelican or snow goose at distance - The crane shows long trailing legs, black primaries on a white body, and slow, stiff wingbeats; pelicans tuck the neck and lack trailing legs.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of Gruidae this model covers, and on what evidence? provenance