LARKFEN FIELD GUIDE PLATE 02 · LF-VSP-001
The Plates / Plate 02 · Common Raven AN INTELLIGENCE STUDY

Common Raven.

One of the world's largest songbirds, and one of the few animals credited with planning, tool use and play. The most widely distributed corvid alive — a habitat generalist of cliff, forest, coast and tundra. This account is the intelligence study the Plate 02 garment is issued from.

ORDER PASSERIFORMES · FAMILY CORVIDAE · AOU CORA · BAND NO. LF-VSP-001
Read the study
Wingspan
116–150cm
Call types
15–30+
IUCN status
LC
Larkfen specimen plate of the Common Raven, Corvus corax — cream line-art on a black field showing the heavy bill, shaggy throat hackles and an intelligence-study data block.
PLATE 02 · cream on field-black · an intelligence study · drawn by hand, redlined
THE VESPER SERIES · LARKFEN FIELD GOODS · AN INTELLIGENCE STUDY
Larkfen Field Guide Plate 02 · The Account
§ The species account

The record, in seven sections.

Measured, marked, voiced and ranged — then verified against the literature and redlined before it ships. Every field below is sourced; the integrity flags stay in.

Corvus corax
Band LF-VSP-001
Verified 2026-06-14

COMMON RAVEN

Corvus corax

Body Mensuration · 3 Specimens SHARED-AXIS RANGE · LF-VIZ-MEASURE
Specimen key Great Blue Heron Common Raven Northern Cardinal
Total Length bill tip → tail tip · cm
HeronArdea herodias 97–137 cm
RavenCorvus corax 56–69 cm
CardinalCardinalis cardinalis 21–23.5 cm
0306090120150
Wingspan tip → tip · cm
HeronArdea herodias 167–201 cm
RavenCorvus corax 116–150 cm
CardinalCardinalis cardinalis 25–31 cm
0306090120150180210
Body Mass adult · g
HeronArdea herodias 2000–3600 g
RavenCorvus corax 690–1,630 g
CardinalCardinalis cardinalis 42–48 g
01000200030004000
Wingspan to scale · 0 → 210 cm
Great Blue Heron 201 cm
Common Raven 150 cm
Northern Cardinal 31 cm
Bar = published min–max range; ticks mark the extremes Axis is per-metric, shared across all three specimens · Data: Cornell Lab / IUCN
A · Measurements
  • Length
    56–69 cm
  • Wingspan
    116–150 cm
  • Mass
    690–1,630 g
  • Size vs crow
    ~1.3–1.4× length
  • Wing chord
    long, broad · flagged
B · Field marks
  • Bill
    massive · nasal bristles
  • Throat
    shaggy hackles
  • Tail
    wedge / diamond
  • Flight
    soars · 4–6 fingers
  • Plumage
    glossy black, sheen
C · Voice
  • Croak
    deep, hoarse rok! / kraa
  • vs. crow
    far lower than a caw
  • Repertoire
    15–30+ call types
  • Mimicry
    imitates in captivity
D · Range & habitat
  • Habitat
    cliff · forest · coast · tundra
  • Range
    Holarctic — N. Hemisphere
  • Generalist
    most widespread corvid
  • Movement
    largely resident
E · Status & life history
  • IUCN
    Least Concern
  • Trend
    increasing in N.A.
  • Diet
    omnivore · carrion–grain
  • Clutch
    4–6 (3–7) eggs
  • Incubation
    18–21 days, ♀
  • Lifespan
    wild often shortband record ~21.9 yr; can exceed 23 yr; captive 40+ yr
F · Observation
  • Obs. date
    __ / __ / ____
  • Locality
    ____________
  • Observer
    ____________
G · Provenance
  • Sources
    Cornell · BoW · Audubon · IUCN
  • Last verified
    2026-06-14
  • Redline
    ☑ accepted
E · Status & population trend
Status & TrendLF-TREND-003
LC Least Concern
LC · NT · VU · EN · CR
Common Raven — Western / Northern Increasing
+1.4%per year
Common Raven abundance index, 1966 to 2019 A rising abundance index from 1966 to 2019, increasing about 1.4 percent per year per USGS Breeding Bird Survey.
196619932019
Decline Increase
Source · USGS BBS 1966–2019 56–69 cm · Wingspan 116–150 cm · resident W/N
Key · how to read this graphic
IUCN Red List status
LCLeast Concernlow risk
NTNear Threatenedwatch
VUVulnerableat risk
ENEndangeredhigh risk
CRCritically Endangeredextreme
Population trend · diverging
Increaserising indexslate
Stableno net changesage
Declinefalling indexoxblood
No datainsufficient survey≠ zero
Magnitudedarker / longer = stronger% · yr
Issue the Vesper tee — $44 Read the study
The Vesper Series · Larkfen Field Goods · an intelligence study
Larkfen Field Guide — Distribution Plate 02 · Range
§ The widest range of any corvid

Resident, almost everywhere.

The raven's claim to fame is reach: the most widely distributed corvid alive, across the whole Holarctic — Arctic tundra to desert to high mountains. The map is nearly one colour on purpose. That near-uniform green is the point.

Corvus corax
largely resident
Holarctic
Corvus corax Common Raven · seasonal range — Holarctic (largely resident)
Seasonal range map of the Common Raven The Common Raven is a year-round resident across nearly the whole North American continent — deep-green resident fill from the contiguous United States north through Canada and into Alaska, with only a thin warm-gray rare-vagrant fringe in the high Arctic. No breeding-only, nonbreeding-only or passage bands: the raven is essentially all-resident, the most widely distributed corvid on Earth.
  • Residentyear-round
  • Breedingsummer only
  • Nonbreedingwinter only
  • Passagemigration only
  • Rarevagrant
  • No datanot surveyed

Only two of the six range states are used here — and that is the honest record. The raven holds the same ground in every season; the legend keeps the unused states (breeding, nonbreeding, passage) visible so the map reads as a true field document, not a decorated one. The Holarctic range continues across Eurasia beyond this North-American frame.

Discrete seasonal polygons · Field Ledger remap · never rainbow
Larkfen Field Guide — Field Marks Plate 02a · ID
§ What to look for

The marks we drew the plate to show.

Five diagnostic marks — three on a perched bird, two in flight — the same five the linocut on the back is drawn to teach.

5 field marks
Corvus corax
Common Raven plate annotated with field marks: heavy bill, shaggy throat hackles, glossy black plumage and the wedge-shaped tail.
Corvus corax · cream on field-black · an intelligence study
Field marks · pointed out
01

Massive bill

Deep, Roman-nosed, with long nasal bristles over the base — far heavier than a crow's.

02

Shaggy hackles

Erectile, pointed throat feathers; a crow's throat is smooth and sleek.

03

Glossy black

Whole bird, with an oily blue-purple sheen in good light.

04

Wedge tail in flight

Long central feathers form a diamond; the crow's fans squared.

05

Fingered wings in flight

Long, narrow; soars on thermals with 4–6 splayed primary "fingers."

Separating raven from crow is the core ID problem this plate answers. On a perched bird the marks are the massive bill, the shaggy throat hackles and the glossy sheen. The two decisive marks are flight ones: the wedge-shaped tail — a long central point versus the crow's squared fan — and the deep, hoarse croak rather than the crow's higher caw. The raven soars and rides thermals; the crow mostly flaps. By length it is only about 1.3–1.4× a crow — not "twice the size" — though far heavier in the hand.

Designed, not generated · every field mark redlined before it ships
Larkfen Field Guide — Voice Plate 02a-v · Sonogram
§ The voice, plotted

The deep croak, as a sonogram.

The raven's voice is a headline field mark — far lower than a crow's caw, with an exceptional 15–30+ call categories. Here the territorial "kraa" croak is plotted the way a recordist reads it: frequency on Y, time on X, loudness as brightness.

15–30+ calls
fund. 0.4–0.9 kHz
Sonogram · CallLF-SONO-001
Common Raven · Corvus corax
"kraa" territorial croak 3 croaks · 1.4 s
fund. 0.4–0.9 kHz
Frequency · kHz
543210
Common Raven "kraa" croak sonogram Three Common Raven kraa croaks over 1.4 seconds; each is a low harmonic stack with a fundamental near 0.5 kilohertz and harmonics rising to about 3 kilohertz, loudest at the low core. kraa kraa kraa measured
00.40.81.21.4 s
Time · seconds
QuietLoud Source · Macaulay Library / stylized
Key · how to read this sonogram
Axes & amplitude
Faint energyupper overtonequiet
Mid energymiddle harmonic↑ louder
Peak energyfundamental ≈0.5 kHzloudest
Y = frequencykHz · X = time↑ = higher pitch
Energy shapes & marks
Harmonic stackthe raven croak — bandedtonal
Contourfundamental linepitch path
Markermeasured segmentsignal
Silenceempty field — no signal≠ data

Three identical croaks over 1.4 s. Each is a stack of evenly spaced bands — a harmonic series on a low fundamental — which is what makes the raven read deep and resonant, where a crow's caw is higher and rougher.

Each croak is a harmonic stack — a low fundamental near 0.5 kHz with evenly spaced overtones above it — which is why the raven reads as deep and resonant where a crow's caw sits higher and rougher. The full repertoire runs to 15–30+ call categories, from this gronk to knocking toc-toc-toc notes, gurgles and bell-like tones.

Frequency on Y · time on X · loudness as brightness — never rainbow
Larkfen Field Guide — Intelligence Study Plate 02b · Cognition
§ The intelligence study

The part most merch skips: the data.

The raven anchors the guide because its cognition is unusually well documented. Here it is charted honestly — ranked, not invented.

i–iv
Compiled 2026-06-14
i · Relative brain size — a ranking, not a figure

We did the part most merch skips: the data. Relative brain size, charted honestly — pigeon to crow to raven — because the claim has to survive someone who actually knows the bird. There is no clean encephalization figure to put on a shirt, so we show the ranking, not a fabricated number.

Relative brain size — ranking only
Pigeon
Crow
Raven
Relative ranking, not to scale. No precise encephalization figure is published for a single shirt claim — corvids are simply among the most cognitively advanced birds.
ii · What "intelligence" means here

The raven anchors the study because its cognition is unusually well documented — problem-solving, planning, food-caching with deception, and play among the behaviours credited to it in the literature.

01 · Behaviour

Problem-solving

Works multi-step tasks; pulls up a hanging food string in repeated stages.

02 · Behaviour

Caching & deception

Hides food and re-hides it when watched — behaviour read as anticipating another's view.

03 · Behaviour

Tool & object use

Manipulates objects to reach a goal; uses cues from other animals to find carrion.

04 · Behaviour

Play

Slides down snowbanks, drops & catches sticks in flight — play rare among birds.

iii · Diet — the omnivore's range

A generalist that eats almost anything. Bars show, schematically, the breadth of the diet by food class — carrion and small animals at the core, with insects, grain, fruit and refuse all taken. (Qualitative, drawn from diet accounts — not a measured budget.)

Food class — share of diet (schematic) · how it's taken
Carrioncore
Small animals & eggshigh
Insectsseasonal
Grain & nutsmoderate
Fruit & refuseopportunist
Schematic · an opportunistic omnivore; follows predators & people to food. Right column = how each class is taken — core & high are staples; insects are seasonal, plant food moderate, refuse purely opportunist.
iv · Annual cycle — pairing & nesting

A largely resident bird, present every month. Ravens pair early and nest sooner than most songbirds — courtship and nest-building through late winter, eggs in early spring on a cliff ledge or tall tree. (Months indicative, not locality-exact.)

Intensity low high
Absent (recorded zero)
No data

Reading the grid. Cell shade is an ordinal bin on a perceptually-uniform sage→deep-green ramp; darker = higher activity. Diagonal hatch = recorded absent. Ravens are resident year-round and pair early: courtship and nest-building through late winter, eggs Feb–May (peak Mar–Apr), young in the nest to fledging Apr–Jun. One brood per year. Indicative, not locality-exact.

Breeding biology
  • Subspecies
    ~11 accepted
  • Nest site
    cliff ledge / tall tree
  • Clutch
    4–6 (3–7) eggs
  • Incubation
    18–21 days, ♀
  • Fledge
    35–49 days · 1 brood/yr
  • Hatch
    blind, naked, helpless
The Vesper Series · cognition compiled & verified 2026-06-14
Larkfen Field Guide — Separation Plate 02c · Confusion Species
§ Three big black birds, told apart

The one confusion every birder must settle.

Any single mark can mislead. Sweep one row — the green (diagnostic) cells are the marks that split the trio — and read them together to make the call secure.

3 corvids
raven · crow · grackle
§ Look-alikes · the separation

Three "big black birds," separated

Field mark Common RavenCorvus corax American CrowCorvus brachyrhynchos Common GrackleQuiscalus quiscula
Tail shape Wedge / diamond tip Long, keeled "boat" tail
Size length 56–69 cm 40–53 cm (smaller) 28–34 cm (smallest)
Throat mark Shaggy hackles
Sheen gloss Iridescent blue-bronze head
Eye color Pale yellow iris
Voice call Deep croak, "gronk" Nasal "caw" Rusty-hinge "readle-eak"
Flight style Soars, rolls, tumbles
White wing flash None None None
Key Diagnostic — the tell Shared — no help here Variable — use with care Not applicable

Any single mark can mislead — but the wedge tail in flight and the deep croak rarely do. Add the bird's size, the shaggy throat and a soaring flight style and the call is secure. The grackle is the easy one out: smaller, with a keeled "boat" tail and a pale yellow eye. This is the separation the plate was drawn to teach. Measurements: Sibley / Cornell Birds of the World.

Diagnostic = sage · shared = slate · N/A ≠ blank · then log the bird
Larkfen Field Guide · LF-VSP-001 Plate 02d · Field Issue
§ The study, issued for the field

One garment, shown the way it ships.

The full study printed across the back, the accession label at the chest. The plate is the back print. The big view is the back; the inset is the front — click the inset to flip, and hover (or drag) over either image to zoom both at the same magnification.

LF-VSP-001
$44 · made to order
FIELD ISSUE · TEELF-VSP-001
BACK · FULL PLATE PRINT Corvus Intelligence Study field tee — the full Common Raven study plate printed across the back, on washed graphite Comfort Colors 1717.
The Vesper Series · LF-VSP-001

Corvus Intelligence Study

Corvus corax

Plate 02, issued as a field garment — the full intelligence study printed across the back, the accession label at the chest. Comfort Colors 1717, garment-dyed pepper, made to order.

Pepper · washed charcoal-green
  • Front printchest label · ~90 mm
  • Back printfull study plate
  • GarmentComfort Colors 1717
  • Band no.LF-VSP-001
$44 Add the field tee →
Hover (or drag on mobile) over either image to zoom · click the inset to flip · see the cap →

The tee is marked the way a real garment is: a small chest spec-label on the front, the full study on the back. The same plate ships large as the poster and the framed wall editions below.

§§ Where the full study ships large
Eastern Backyard Index poster, hung on cream.
PosterLF-LIFE-002

Eastern Backyard Index — Poster

Twelve common visitors · 18×24

$38Open →
Bird-Band Glyph Cap, stone, embroidered LF band ring.
CapLF-FIELD-001

Bird-Band Glyph Cap

Federal-style band ring · field issue

$38Open →
The Corvus study printed full across the tee back.
TeeLF-VSP-001

Corvus Intelligence Study

Full study, across the back · pepper

$44Open →
The plate ships large · the tee carries the record
Larkfen Field Guide — Conservation Plate 02e · 5% to Cornell Lab
5%

The patch is worth keeping.

5% of net sales goes to the Cornell Lab of Ornithology — the people behind eBird and Merlin, the citizen-science record these plates are built on. The Common Raven is IUCN Least Concern and increasing in North America — a generalist that thrives where the wild edge survives.

Field readout
6 species in guide
100% field marks verified
5% net to conservation
© 2026 Larkfen · 5% of net sales to the Cornell Lab of Ornithology
Larkfen Field Guide — The Plates Index · See Also
§ From the same guide

From the same guide.

The Local Patch
Larkfen Field Goods
No.PlateBinomialKindOpen
Plate 01 Great Blue HeronThe standing wader Ardea herodias Species account Open →
Plate 03 Northern CardinalLife List N°001 Cardinalis cardinalis Species account Open →
LF-LIFE-002 The IndexTwelve common visitors Eastern backyard Poster Open →
LF-FIELD-001 Bird-Band Glyph CapField issue Federal band ring Cap Open →
The Local Patch · Larkfen Field Goods