Every layer below draws on the sources above — open one to explore it, or use ← → to move between tabs.
NarrativeWikipediaarticle
Traits & measurements5 literature sources41 traits
Occurrence & distributionGBIF · OBIS · PBDB1 585 120 records
DNA & barcodingBOLD4 specimens
Genome at a glanceGoaT · NCBI≈1.4 Gbp
Deep timePBDB4 fossils
01Narrative
The western gull (Larus occidentalis) is a large white-headed gull that lives on the west coast of North America. It was previously considered conspecific with the yellow-footed gull (Larus livens) of the Gulf of California. The western gull ranges from British Columbia, Canada to Baja California, Mexico.
No narrative description available for this taxon yet.
⚠ sources differ — AnAge: 932 g · AmnioteDB: 932 g · AVONET: 923 g · EltonTraits: 923 g · SeaLifeBase: 1 010 g
Body mass (female)809 g
Body mass (male)994 g
Hand-wing index51
Kipp's distance201 mm
Secondary length193 mm
Tail length145 mm
Tarsus length64.2 mm
Wing length398 mm
Life cycle & reproduction11
Age at maturity (male)1 460 days
Age at sexual maturity1 825 days
Egg mass91.9 g
Fledging age49.5 days
Gestation27 days
Growth rate0.136 /day
Incubation26.75 days
Litter size3
Litters per year1 /year
Max. longevity407 months
Neonate mass67.5 g
Diet & foraging8
Fish30 %
Ground80 %
Invertebrate20 %
Scavenge20 %
Trophic levelcarnivore
Trophic nicheOmnivore
Vertebrate endotherm30 %
Water around surface20 %
Habitat & environment6
HabitatMarine
Habitat saltwateryes
Habitat zoneothers
Migration2.0
Primary lifestyleGeneralist
Range size91 634 km²
Physiology & chemistry1
Metabolic rate3.44 W
Other traits1
Vulnerability47.2
05DNA & barcoding4 specimens
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 Larus occidentalis has left across the world's sequence archives.
At a glance
DNA specimens4
BINs1
Marker genes1
Countries2
The DNA barcodethe species' typical barcode, built from every sequenced specimen
COI-5P694 bp consensus4 specimens
ACGT
▸ drag or hover over the strip to read any position — letter and how much it varies
Violet ticks below the strip = positions where individuals differ; flat = the species' unchanging signature. 99% of positions are identical in every specimen.
Where individuals differ — all 6 variable positions, in barcode order
Each circle is a barcode variant; bigger = more specimens, colour = region. Lines join the most similar variants and the tick marks count the mutations between them — a tight cluster is one “dialect”, a long line a more divergent lineage. Click a circle to list its actual specimens.
Diversity (π)0.53%
Haplotypes3
BIN1
Most divergent pair0.72%
N.America
Closest relatives by DNA barcode
The species whose COI barcode is most similar to this one — a quick “who is this most like”. The percentage is how much the barcode differs; it approximates, but is not, the full evolutionary tree.
★ 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.
★COI-5P
animal barcode
06Genome at a glanceGoaT · NCBI
The complete instruction manualLarus occidentalis 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
Genome size≈1 443 155 878 bp assembly estimate
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).
BACTERIUM Carsonella ruddii0.00016 Gb
FUNGUS0.04 Gb
INSECT0.25 Gb
THIS GENOME Larus occidentalis1.44 Gb
HUMAN3.2 Gb
WHEAT17 Gb
FERN Tmesipteris160.45 Gb
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
Fossil range2.58–0 Ma Pleistocene, Holocene
Dated fossil finds4
StatusStill living record runs to the present
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 Larus occidentalis. Above itBeside it, each dot is one dated fossil find — few enough to count, so they are drawn individually rather than as a graph.
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
Coordinate accuracy94% within 1 km
≤100 m 72 585≤1 km 10 416≤10 km 3 772>10 km 1 382
88 155 georeferenced · 1 496 099 without coordinates
Open the mapobservation + sensor1 584 254
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.
Coordinate accuracy42% within 1 km
≤100 m 109≤1 km 168≤10 km 273>10 km 102
652 georeferenced · 200 without coordinates
Open the institutions mapphysical evidence852
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
10Collections & institutions
Holding institutions27 of 45 geolocated
Institutions and collections holding physical, vouchered specimens of this species — click a row to fly to it on the map.
Institution
Specimens
CASlocation not on record
136
Seattle, US
96
US
91
Los Angeles, US
71
Tacoma, US
67
Cambridge, US
50
Denver, US
44
Chongqing Museumlocation not on record
29
Washington State University, Charles R. Conner Museumlocation not on record
28
University of California Los Angeleslocation not on record
25
Berkeley, US
24
San Diego, US
23
Ann Arbor, US
17
München, DE
15
Museo civico La Terra e l'Uomo di Crocetta del Montellolocation not on record
13
Wuzhou, CN
13
Washington, US
10
Zacatecas, MX
9
Vancouver, CA
8
Delaware Museum of Nature and Sciencelocation not on record
7
Iowa City, US
7
Philadelphia, US
7
Albany, US
6
5
Sam Noble Oklahoma Museum of Natural Historylocation not on record
4
Natural History Museum Rotterdamlocation not on record
3
Texas Cooperative Wildlife Collectionlocation not on record
3
Chicago, US
3
Santa Cruz, US
3
Mexico City, MX
2
Edmonton, CA
2
Ohio State University - Bird Division, Columbus, OH (OSUM)location not on record
2
Ithaca, US
2
University of Victorialocation not on record
2
New Haven, US
2
Arizona State University Biocollectionslocation not on record
2
Mongolian Museum of Natural Historylocation not on record
2
Chicago, US
1
Toronto, CA
1
Natural History Museum of Utahlocation not on record
1
Philip L. Wright Zoological Museumlocation not on record
1
NCBlocation not on record
1
St. Paul, US
1
Ohio Wesleyan University Museum of Natural Historylocation not on record
1
Royal Saskatchewan Museumlocation not on record
1
45 institutions · 841 of 852 vouchered records shown · 11 without an institution code
WikipediaWikimedia Foundation2 languages↗
GBIFGlobal Biodiversity Information Facility1 556 557 records↗
OBISOcean Biodiversity Information System28 559 records↗
BOLD SystemsCentre for Biodiversity Genomics4 specimens↗
Open Tree of LifeOpenTreephylogeny backbone↗
GoaTGenomes on a Tree · Sangergenome & karyotype↗
NCBIUS National Library of Medicinegenome & karyotype↗
Paleobiology DatabasePBDB consortiumfossil record↗
IOC World Bird ListIOCbird checklist↗