Calidris pugnax
(Linnaeus, 1758) · speciesAt a glance
Sources11 archives
Databases and archives Calidris pugnax's data was compiled from.
WikipediaWikimedia Foundation18 languages↗
BioWikiNetmultilingual Wikipediamultilingual↗
GBIFGlobal Biodiversity Information Facility1 371 253 records↗
ENAEuropean Nucleotide Archive · EMBL-EBI41 eDNA detections↗
BOLD SystemsCentre for Biodiversity Genomics43 specimens↗
GoaTGenomes on a Tree · Sangergenome & karyotype↗
NCBIUS National Library of Medicinegenome & karyotype↗
Paleobiology DatabasePBDB consortiumfossil record↗
WikidataWikimedia Foundationstructured facts↗
IOC World Bird ListIOCbird checklist↗
GLoBIGlobal Biotic Interactionsbiotic interactions↗Every layer below draws on the sources above — open one to explore it, or use ← → to move between tabs.
The ruff (Calidris pugnax) is a medium-sized wading bird that breeds in marshes and wet meadows across northern Eurasia. This highly gregarious sandpiper is migratory and sometimes forms huge flocks in its winter grounds, which include southern and western Europe, Africa, southern Asia and Australia. The ruff is a long-necked, pot-bellied bird. This species shows marked sexual dimorphism; the male is much larger than the female (the reeve), and has a breeding plumage that includes brightly coloured head tufts, bare orange facial skin, extensive black on the breast, and the large collar of ornamental feathers that inspired this bird's English name. The female and the non-breeding male have grey-brown upperparts and mainly white underparts. Three differently plumaged types of male, including a rare form that mimics the female, use a variety of strategies to obtain mating opportunities at a lek, and the colourful head and neck feathers are erected as part of the elaborate main courting display. The female has one brood per year and lays four eggs in a well-hidden ground nest, incubating the eggs and rearing the chicks, which are mobile soon after hatching, on her own. Predators of wader chicks and eggs include mammals such as foxes, feral cats and stoats, and birds such as large gulls, corvids and skuas. The ruff forages in wet grassland and soft mud, probing or searching by sight for edible items. It primarily feeds on insects, especially in the breeding season, but it will consume plant material, including rice and maize, on migration and in winter. Classified as "least concern" on the IUCN Red List criteria, the global conservation concerns are relatively low because of the large numbers that breed in Scandinavia and the Arctic. However, the range in much of Europe is contracting because of land drainage, increased fertiliser use, the loss of mown or grazed breeding sites, and over-hunting. This decline has seen it listed in the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).
No narrative description available for this taxon yet.
Size & morphology13
Life cycle & reproduction10
Diet & foraging10
Habitat & environment6
A DNA barcode is a short, standardised stretch of genes that works like a fingerprint — enough to tell one species from another. Below is the molecular trace Calidris pugnax has left across the world's sequence archives.
At a glance
★ the standard DNA barcode for this group — the short region actually read to tell this species apart. The rest are extra genes sequenced along the way.
Besides the big genome in the nucleus, cells carry a small, circular loop of DNA inside the cell's energy factories — the mitochondria. It is inherited almost only from the mother and is a leftover from ancient bacteria that moved into the cell. The mitochondrial markers above (ND*, COX, CYTB…) are read from exactly this loop. Outer ring = one strand, inner ring = the other.
The complete instruction manual Calidris pugnax carries — its genome. We read it from three angles — how big it is, how the DNA is packed into chromosomes, and how completely it has been sequenced — and explain how to read each value as you go.
Genome sizehow big the whole instruction manual is
Measured in base pairs (bp) — the individual letters of DNA (human ≈ 3.2 Gb, a bacterium a few million). The chart places this genome on a logarithmic scale — each step to the right is ten times bigger — among reference organisms. Across species a bigger genome loosely tracks with larger cells, slower growth and lower-energy lifestyles (powered flight favours small genomes) — yet it does not imply more genes or a more advanced organism (the long-standing C-value paradox).
Sequencing statusassembly quality — how far to trust these numbers
Assembly level tells you how finished the sequence is — from fragmented contigs, through scaffolds, up to a full chromosome-level assembly. BUSCO % estimates completeness: the share of genes expected to be present that were actually found. These describe the data quality, not the organism.
How far back this lineage goes — and how we know. Everything here is measured in Ma, short for “mega-annum”: millions of years ago. The chart reads left to right like a calendar of the Earth, from the deep past on the left to today at the right edgetop to bottom like a core drilled through the Earth, from the deep past at the top down to today at the bottom.
At a glance
When this lineage existed
How to read this: the coloured strip along the bottomdown the left is the geological calendar — the standard epochs (Pliocene, Pleistocene…) every museum uses, shown so you can see which chapter of Earth's history this lineage lived in. This lineage is a young one, so the strip is zoomed in to epochs — the finer subdivisions inside a period. The solid bar is the fossil range: the span between the oldest and the youngest fossil that palaeontologists have assigned to Calidris pugnax. Above itBeside it, each dot is one dated fossil find — few enough to count, so they are drawn individually rather than as a graph. The orange marker is the DNA clock: DNA accumulates mutations at a roughly steady rate, so comparing this species' DNA with its relatives estimates when the lineage split off — independently of any fossil. Where the DNA reaches further back than the oldest fossil, the gap is hatched: the ghost lineage. It means the lineage was already out there, but has left us nothing we have dug up yet.
How it livedPBDB
Record type1 371 260 records
Origin
Range
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
Museum / Voucheredphysical evidence
Backed by a physical specimen — a herbarium sheet, sample or voucher held in a collection. “Vouchered” means supported by material evidence, not just an observation.
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
Holding institutions26 of 44 geolocated
Institutions and collections holding physical, vouchered specimens of this species — click a row to fly to it on the map.
| Institution | Specimens |
|---|---|
| Helsinki, FI | 304 |
| Musée des Confluenceslocation not on record | 199 |
| Brussels, BE | 104 |
| Copenhagen, DK | 80 |
| RBINS-Scientific Heritagelocation not on record | 75 |
| Oulu, FI | 69 |
| Stockholm, SE | 65 |
| Paris, FR | 52 |
| New Haven, US | 44 |
| Geneva, CH | 42 |
| Seattle, US | 37 |
| Salzburg, AT | 35 |
| Tromsø, NO | 30 |
| Ann Arbor, US | 30 |
| ZMAAlocation not on record | 27 |
| Kuopio, FI | 26 |
| Museums Victorialocation not on record | 20 |
| Berkeley, US | 18 |
| Institute of Plant and Animal Ecology UB RASlocation not on record | 16 |
| Liverpool, GB | 15 |
| Australian National Wildlife Collectionlocation not on record | 8 |
| Museo civico La Terra e l'Uomo di Crocetta del Montellolocation not on record | 8 |
| CBDClocation not on record | 7 |
| Rovaniemi, FI | 6 |
| Vancouver, CA | 5 |
| Adam Mickiewicz University in Poznańlocation not on record | 5 |
| Western Australian Museumlocation not on record | 5 |
| Auckland, NZ | 4 |
| Natick, US | 4 |
| STOCKHOLM, SE | 4 |
| Thiruvananthapuram Natural History Museumlocation not on record | 3 |
| Zacatecas, MX | 3 |
| SMNHTAUlocation not on record | 3 |
| Forssa, FI | 3 |
| Bonn, DE | 2 |
| Iowa City, US | 2 |
| DOI/NPS, Salem Maritime National Historic Sitelocation not on record | 2 |
| 730location not on record | 2 |
| KU Leuvenlocation not on record | 1 |
| Natural History Museum, Londonlocation not on record | 1 |
| Texas Cooperative Wildlife Collectionlocation not on record | 1 |
| TMPMlocation not on record | 1 |
| Wuzhou, CN | 1 |
| Bergen, NO | 1 |
Where the DNA of Calidris pugnax was picked up in samples of water, soil or air — nobody saw the organism, only its DNA left behind. A trace is a clue that the species was near, not a confirmed sighting.
Signal
Where its DNA was found
How strong is each trace?
Modelled climatemodelled
How to read this: each dot is one detection of this species' DNA in an environmental sample. The confidence meter weighs how many independent studies and places back up the signal — one detection in one study is a hint; many across several studies is solid. Records dated before 2008 (when eDNA methods began) are treated as likely mislabeled and left off the map.