Offshore pelagic · Saltwater
Striped marlin
Kajikia audax
Native Pacific and Indian Ocean epipelagic billfish, highly migratory and oceanic; not landlocked or introduced. In US waters it is chiefly an eastern North Pacific (California Current / Baja) and Hawaii-region species.
Also called stripey.
- Offshore
- Regulated context
- 4 of 4 overlays reviewed
- Reviewed 2026-08-27
Before you target this fish
Regulated context — check the rules for the exact water
Where this applies US West Coast (California/Oregon/Washington) recreational and for-hire fishery under the Pacific HMS FMP; separately, Hawaii and Pacific Insular Areas operate under different Billfish Conservation Act exemptions.
The reviewed context, unedited
Commercial sale of billfish (including striped marlin) is prohibited in the continental US under the Billfish Conservation Act; Hawaii and Pacific Insular Areas are exempted and may land, retain, and sell billfish caught there. That Act's language targets sale and possession-for-sale, not recreational catch and retention. California's 2025 ocean sport fishing regulations set a bag limit of one marlin (species not further subdivided in that rule) per angler per day and give striped marlin no further species-specific state rule; commercial and for-hire HMS vessels need a federal Pacific HMS permit. This dossier could not confirm the assignment-hint claim of a blanket catch-and-release-only US recreational fishery for striped marlin -- confirm current retention rules, any tournament-specific release requirements, and permit needs before fishing.
Rules for this fish change at a state line and sometimes inside one. Check the ones that apply to the exact water you are standing on before you act on anything here — this record is biology, not permission.
Take this somewhere
This page is the record. The reading is what happens when you add water, a season and a temperature to it — that is where the families below get ranked against each other instead of just listed.
Those three links carry the fish and nothing else. No conditions were declared on this page, so none travel, and the link says so rather than sending an empty reading.
The half nobody publishes
What this record does not know
Everything else on this page comes from a named agency or peer-reviewed source. This is the other side of that: the questions a reviewer went looking for an answer to and came back without, and the fields the record leaves empty because filling them would mean guessing.
It is here rather than at the bottom because a page that only shows what it knows is easy to read as a page that knows everything. For Striped marlin there are 12 of them.
Named by a reviewer
9Somebody looked for this and wrote down that they did not find it.
- Behaviour
Thermal preference figures disagree between a global agency source (68-77°F) and a regional peer-reviewed telemetry study (roughly 79-88°F); not reconciled, and it is unclear how much of the difference is regional versus methodological.
Cold-edge and warm-edge tolerance limits (as distinct from preference) were not found in reviewed sources.
A US West Coast seasonal-occurrence calendar tied to warm-water events was not found in reviewed sources; see seasonal_calendar gaps.
- Identification
Longevity estimates conflict between sources (about 10 years vs. about 20 years) and were not reconciled.
IUCN Red List category is unresolved: one institutional species account (Fishes of Australia) states Near Threatened, while a sportfishing-industry synthesis article states Least Concern; the IUCN Red List's own page could not be loaded directly during this review (persistent server error). Recorded as a disagreement rather than picked.
- Forage
Seasonal diet shifts specific to the eastern Pacific/US fishery were not found.
A quantified ontogenetic diet shift (beyond larval zooplankton to adult fish/squid) was not found.
- Season
A month-by-month US West Coast seasonal-occurrence calendar (e.g. tied to warm-water intrusions) was not found in the agency and peer-reviewed sources reviewed; the Pacific Fishery Management Council's HMS background page confirms federal management status but gives no seasonal timing.
Winter behavior/habitat use was not specifically sourced; only warm-season habitat use is documented above.
Absent from the record
3No reviewer wrote a gap here. The field is simply empty, which is its own answer.
- Water temperature
No agency or peer-reviewed temperature band for Striped marlin was found that a review would accept. The reading runs without one rather than borrowing a number from a related fish.
- Identification
No reviewed image. A photograph is only in this catalog when an agency or a named creator labelled the subject, and nobody has cleared one for this species yet.
- Population context
No regional population profile is registered. The species-level reading stands on its own; it does not silently become a local one.
Where the record puts it
Water and range
Offshore
4 reviewed holding classes- Temperature break
- Current rip
- Seamount
- Open-water bait school
DepthEpipelagic; spends the large majority of time in the surface mixed layer above the thermocline (commonly cited as roughly the top 200 m), with only brief deeper excursions.
Moving waterOceanic and highly mobile; concentrates in frontal zones where a cooler current meets warmer water and around eddy margins, because these features aggregate the epipelagic baitfish and squid it hunts visually. A peer-reviewed telemetry study also found striped marlin associating with seamount and boundary-current features generically, not with any single named feature.
LightReviewed sources are consistent with a daytime-active pattern: one reference database lists the species as diurnal, and an independent peer-reviewed telemetry study found reduced horizontal movement at night versus daytime, consistent with a more visually-driven daytime hunting style.
Thermal band
Temperature
No reviewed temperature band
Nobody publishes a preferred or active temperature range for Striped marlin that a review would accept. Borrowing one from a related fish would look like knowledge and behave like a guess, so the reading runs without it and says which parts of the answer that weakens.
How it uses water
Behaviour
Reviewed peer-reviewed telemetry tracked individuals independently with no mention of coordinated group movement, consistent with a broadly solitary pelagic hunter.
A visual, pursuit-hunting predator; one source notes striped marlin have the thinnest bill of any billfish and slash at prey rather than impaling it as some other billfish do. Diet is opportunistic on whatever epipelagic baitfish and squid are locally concentrated. Diet capacity is not evidence of a current bait event.
Described as diurnal (day-active) in a university reference database; an independent peer-reviewed telemetry study found tagged fish covered less horizontal distance at night than during the day, consistent with reduced nocturnal activity.
Temperature-driven behaviourNOAA describes a preferred temperature range of about 68-77°F (20-25°C). A regional peer-reviewed telemetry study (western Indian Ocean) found tagged fish spending the large majority of surface time in notably warmer water (roughly 79-88°F / 26-31°C); this is recorded as a regional finding rather than merged into the catalog thermal band, given the disagreement with NOAA's broader figure -- see gaps.
Depth movementSpends the large majority of time in the surface mixed layer above the thermocline; deeper excursions are brief.
Facing the currentConcentrates at frontal zones where cooler and warmer water masses meet, since these fronts concentrate the prey it hunts visually.
Spawning (conservation context)Batch spawner; NOAA describes spawning occurring in the central Pacific and off central Mexico (broad ocean-basin regions, not a named site), with juveniles subsequently moving eastward toward the Baja California region in high abundance. Spawning water and any staging concentration are conservation context only and are not described as holding water.
Where the general rule stops
- Do not treat the IUCN Red List category as settled here: reviewed sources disagreed (see identification.gaps), and international stock status varies sharply by ocean region -- NOAA describes the eastern Pacific stock as not subject to overfishing while describing the central/western Pacific stock as subject to overfishing.
What it can eat
Forage
- Small forage fish
- Larger prey fish
- Squid / cephalopods
Preys on schooling epipelagic fish (mackerel, sardines, anchovies, small tuna) and cephalopods (especially squid); off southern California it has been described feeding at the surface on small coastal fish and squid. Diet capacity is not evidence of a current bait event.
- Feeding style
- Opportunistic
- Feeding zone
- Pelagic
By life stage
- Young of year
- Planktonic larvae feed on zooplankton.
- Adult
- Adults prey on schooling baitfish (mackerel, sardines, anchovies, small tuna) and squid.
Prey sizeDiet shifts from zooplankton at the larval stage to schooling baitfish and squid as juveniles and adults.
Diet capacity is not proof that a bait event is happening now; observed current forage still comes from a direct sighting, not from this dossier.
Through the year
Season
Spring
- Where they sit
- Frontal zones and eddy margins in offshore water where cooler and warmer water masses meet, concentrating epipelagic baitfish and squid.
- Temperature
- Within or approaching the roughly 68-77°F preferred band.
What would count against it
- Assuming a fixed regional arrival date; a sourced calendar for this was not found.
Spawning season (spring/summer, broad ocean-basin scale per NOAA); spawning water is excluded from holding-water guidance.
Summer
- Where they sit
- Offshore frontal zones, eddy margins, and seamount-associated water within the preferred thermal band.
What that changesTrolling spread and live-bait slow troll along visible current seams and temperature breaks; chum-established drift where a scent trail can be maintained in open water.
What would count against it
- Treating a single warm-water event as proof of increased local abundance without a supporting source.
Spawning season continues; spawning water is excluded from holding-water guidance.
Spawning · Spring, Summer
Batch spawner; NOAA describes spawning in the central Pacific and off central Mexico (broad ocean-basin regions, not a named site), with juveniles subsequently moving eastward toward the Baja California region in high abundance. Sexual maturity is reached at roughly 1-2 years (males) to 1.4-2.5 years (females). Spawning water and any staging concentration are conservation context only and are not described as holding water.
Recorded as conservation context. No spawning site, staging concentration or migration bottleneck is named anywhere in this catalog, because naming one is how a population gets fished out.
Telling it apart
Identification
What to look at
- First dorsal fin is markedly taller relative to body depth than blue marlin's, with a pointed front lobe.
- Cobalt-blue vertical body stripes are well-defined and evenly spaced, and -- unlike blue marlin's stripes -- remain visible after death.
- Pectoral fins are pointed rather than the rounded, fully body-depressible pectoral fin of blue marlin.
- Body is more laterally compressed ('leaner,' more severely tapered) than a blue marlin of comparable length.
- Average adult length
- Average length around 9.5 ft (2.9 m).
- Common angling size
- One institutional species account describes roughly 11.5 ft (350 cm) and about 220 lb (100 kg) as more typical of landed fish than the documented maximum.
- Typical weight
- Roughly 220 lb (100 kg) is described as more typical than the documented maximum size.
- Maximum documented
- NOAA cites up to about 14 ft and 250-450 lb; another account cites a maximum length of 13.8 ft (4.2 m) and up to about 490 lb (220 kg). Treated as approximate given the spread between sources.
- Longevity
- Estimates conflict between sources: one account cites a maximum age of about 10 years, NOAA cites a maximum documented lifespan of about 20 years. Not reconciled here.
What it gets confused with
- Blue marlin (Makaira nigricans)
- Blue marlin have a proportionally shorter, more rounded dorsal fin, a bulkier and rounder body, rounded pectoral fins that fold flat against the body, and body stripes that fade quickly after death.
- White marlin (Kajikia albida)
- White marlin are much smaller-bodied with rounded (not pointed) pectoral and dorsal fin tips, and are an Atlantic species not normally encountered in the Pacific/Indian Ocean range of striped marlin.
What follows from all of that
Presentation families
Offshore
Trolling spread
Pull several baits at different distances and depths so one crosses a fish travelling through open water.
- stagger the spread
- match speed to the bait
- work the edge, not the middle
- turn on marks
What it asks of the tackle
- Depth control
- Moderate
- Sensitivity
- Low
- Casting distance
- None
- Weight range
- Trolling weights and heads
- Cover resistance
- Low
- Line visibility
- Secondary
- Retie frequency
- Low
Live-bait slow troll
Move live bait just fast enough to cover water while it still swims naturally.
- barely-moving speed
- bait leads the boat
- let it swim
- drop back on a follow
What it asks of the tackle
- Depth control
- Moderate
- Sensitivity
- High
- Casting distance
- None
- Weight range
- Unweighted to 4 oz
- Cover resistance
- Low
- Line visibility
- Low
- Retie frequency
- Moderate
Chum-established drift
Establish a scent trail and drift baits back through it at the speed the current is already moving.
- consistent trail
- unweighted or lightly weighted drop-back
- match the sink to the drift
- do not outpace the trail
What it asks of the tackle
- Depth control
- Low
- Sensitivity
- High
- Casting distance
- None
- Weight range
- Unweighted to 2 oz
- Cover resistance
- Low
- Line visibility
- Low
- Retie frequency
- Moderate
What moves them for this fish
Reviewed rules that push particular families up when the conditions match. Each one names the conditions it needs and why it exists, so you can disagree with it.
Striped marlin concentrate at frontal zones where cooler and warmer water meet because those fronts concentrate the baitfish and squid it hunts visually, so presentations that cover or work that seam outrank ones that do not.
When
Offshore · Temperature break, Current rip
Moves up
Trolling spread, Live-bait slow troll, Chum-established drift
Reviewed 2026-08-30
This is a visual, pursuit-hunting predator described as diurnal, with reduced movement documented at night, so daylight favors moving presentations a fish can see and chase.
When
Offshore · Bright or Mixed
Moves up
Trolling spread, Live-bait slow troll
Reviewed 2026-08-30
The same telemetry finding of reduced nocturnal horizontal movement argues against weighting active, wide-searching presentations as heavily once light drops, since a visual hunter covering less ground is less likely to encounter them.
When
Offshore · Low light or Night
Moves up
Trolling spread, Live-bait slow troll
Reviewed 2026-08-30
Where every sentence came from
Sources
Agency
NOAA Fisheries, Striped Marlin species page
Used for habitat, thermal band and presentation families; identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-27.
Agency
California Department of Fish and Wildlife, 2025 California Ocean Sport Fishing Regulations
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
Agency
NOAA Fisheries, Billfish Conservation Act (laws and policies page)
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
Peer reviewed
Used for habitat, thermal band and presentation families; behaviour; season. Read 2026-08-30, next check 2026-11-27.
Synthesis
Fishes of Australia (Museums Victoria), Kajikia audax species account
Used for habitat, thermal band and presentation families; identification; forage. Read 2026-08-30, next check 2026-11-27.
Synthesis
Animal Diversity Web (University of Michigan), Tetrapturus audax account
Used for behaviour; forage. Read 2026-08-30, next check 2026-11-20.
Synthesis
Billfish species-identification guide (dorsal fin, stripe persistence, pectoral-fin traits)
Used for identification. Read 2026-08-30, next check 2026-11-19.
A source with no link predates the rule that one has to carry a URL. It is still a real citation and still checkable; it just takes a search rather than a click, and that is worth knowing before you rely on it.