Freshwater predator · Freshwater
Bowfin
Amia calva
Ancient native predator of eastern North American low-gradient rivers, floodplains, swamps, backwaters, lakes, and bayous.
Also called grinnell, cypress trout, dogfish, mudfish, mud pike, choupique, ruddy bowfin, grinnel.
- Flowing water
- Stillwater
- Ordinary target
- 4 of 4 overlays reviewed
- Reviewed 2026-08-27
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 Bowfin there are 19 of them.
Named by a reviewer
16Somebody looked for this and wrote down that they did not find it.
- Behaviour
A sourced numeric preferred-temperature band. The catalog carries 68–80°F; no agency or peer-reviewed source reached supported a specific band, so it is not restated as fact here.
Cold-front or barometric response with primary-source support.
Water clarity response with primary-source support.
Angling-pressure response with primary-source support.
Non-nesting territoriality and home-range size.
Autumn and winter behaviour — the agency accounts reached are almost entirely spring and summer.
- Identification
Which taxon a given account describes. Bowfin was split in 2022 into Amia calva (Atlantic slope) and Amia ocellicauda (Mississippi and Ohio basins, Great Lakes), and most sourced agency accounts predate or straddle that split. This record is written species-level and may mix the two.
A sourced continent-wide mean length and weight rather than state-by-state figures.
Reconciliation of the 10–12 year figure in state accounts with the >30 year otolith result.
A sourced field key separating Amia calva from Amia ocellicauda on characters an angler can use in hand, beyond general colour and eyespot prominence.
- Forage
Season-by-season diet composition from a primary source. No sourced seasonal diet breakdown was found, so seasonalDiet is omitted rather than invented.
Quantitative stomach-content studies attributable to Atlantic-slope Amia calva as distinct from Mississippi-basin Amia ocellicauda.
Whether mollusk feeding (given by Indiana DNR) is incidental or a real dietary component; the catalog forage list does not carry mollusks for this species.
- Season
Fall and winter entries. No agency or peer-reviewed source reached described bowfin habitat, depth or activity outside the spring nesting period and the general warm-water summer pattern, so those seasons are omitted rather than extrapolated.
A sourced thermal band to anchor thermalContext numerically.
Whether the day/night depth split reported by Missouri Department of Conservation holds across the range or is specific to its lowland swamp populations.
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 Bowfin 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
Flowing water
5 reviewed holding classes- Eddy
- Side channel
- Submerged wood
- Deep pool
- Undercut bank
Stillwater
5 reviewed holding classes- Weed edge
- Inside weedline
- Wood
- Basin
- Inlet
DepthOften deeper or more covered by day, then moves shallower along weed and wood edges at night.
Moving waterStrong fit is slack, backwater, and low-gradient habitat with vegetation or wood; not a sustained-current specialist.
LightLow light and night favor shallower feeding; daylight commonly reinforces depth and cover.
Thermal band
Temperature
No reviewed temperature band
Nobody publishes a preferred or active temperature range for Bowfin 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
Adults are not a schooling species. Agency accounts describe individually held ambush positions in cover rather than aggregations.
Indiana DNR describes bowfin as ambush predators that hunt mostly at night. USGS describes them as voracious piscivores that will consume virtually any animal small enough to eat. Pennsylvania Natural Heritage describes opportunistic feeding across many small animal groups.
Missouri Department of Conservation: bowfin hide in deeper water during daylight and feed in shallow water at night. Indiana DNR gives ambush feeding typically at night. The Arkansas account also gives nocturnal adult feeding. Spawning itself occurs at night (Florida FWC).
Seasonal activitySpawning occurs in spring across the sourced range — April into early June (Missouri Department of Conservation), early April into May or early June (Indiana DNR), April–June (Arkansas). Season-by-season activity outside the spawning period is not covered by the agency sources reached.
Temperature-driven behaviourAgency accounts consistently place bowfin in warm, often poorly oxygenated lowland water: swamps, sloughs, oxbows, ditches, backwaters and heavily vegetated lakes (Florida FWC, NC Wildlife Resources Commission, Missouri Department of Conservation, Indiana DNR, Pennsylvania Natural Heritage). Bowfin gulp air at the surface using a vascularised, lung-like gas bladder, which lets them hold in stagnant, low-oxygen water that excludes most other predators; peer-reviewed work on Amia calva documents this bimodal gas exchange and its control under hypoxia. No sourced numeric preferred-temperature band was found, so none is asserted here.
Depth movementMissouri Department of Conservation: deeper water in daylight, shallow water to feed at night.
Water levelNC Wildlife Resources Commission notes bowfin can burrow into mud to survive drought. That is a survival response to water loss, not a feeding response.
CoverDense aquatic vegetation, weedy shallows, sloughs, oxbows, backwaters, ditches and submerged wood (Missouri Department of Conservation, NC Wildlife Resources Commission, Indiana DNR, Arkansas). Missouri adds a daylight/dark split: deeper water by day, shallow vegetated water to feed at night.
Open waterMissouri Department of Conservation places bowfin in backwaters and oxbows along large rivers rather than in main channels. Indiana DNR gives marshes, lakes and vegetated backwaters of large rivers.
Predator avoidanceIndiana DNR interprets the dark spot at the tail base as a false eye that confuses predators.
TerritoryNest-guarding males defend the nest and then the fry school (Missouri Department of Conservation, Florida FWC, Indiana DNR). Defended feeding territories outside the nesting period are not described in the sources reached.
Spawning (conservation context)Spring spawner. Males clear and guard a nest depression in shallow, heavily vegetated water from about April into early June, spawn at night, then guard the eggs and afterwards the fry school until the young reach roughly 4 in (Missouri Department of Conservation, Florida FWC, Indiana DNR, Pennsylvania Natural Heritage). Larvae anchor themselves with an adhesive organ. Nesting cover, nests and guarding males are conservation context and are excluded from target guidance.
Where the general rule stops
- Surface air-gulping is respiratory behavior and should not be interpreted as surface feeding.
- Male nest and fry guarding is a reproductive state, not a recommendation.
What it can eat
Forage
- Small forage fish
- Larger prey fish
- Crustaceans
- Amphibians
- Aquatic insects
Adults take fish, crayfish, frogs, worms, mollusks and aquatic insects (Pennsylvania Natural Heritage, Missouri Department of Conservation, Indiana DNR). Missouri ranks gizzard shad first where present, then golden shiners, bullheads and sunfish. NC Wildlife Resources Commission adds snakes, small rodents, turtles and leeches. USGS describes bowfin as voracious piscivores that will consume virtually any animal small enough to eat. This is dietary capacity, not evidence of a current forage event.
- Feeding style
- Opportunistic
- Feeding zone
- Mixed
By life stage
- Young of year
- Microcrustaceans and small zooplankton; the Arkansas account gives a shift onto aquatic insects at about 40 mm.
- Juvenile
- Aquatic insects until roughly 4 in, then increasingly fish (Indiana DNR).
- Adult
- Predominantly fish, plus crayfish, frogs, mollusks and aquatic insects (Indiana DNR, Missouri Department of Conservation).
Prey sizePrey size tracks gape. The catalog larger_prey_fish class belongs to large adults, not to young fish still on insects.
Ontogenetic shiftMicrocrustacean and insect feeding gives way to predominantly piscivorous feeding at roughly 4 in (Indiana DNR, Missouri Department of Conservation, Arkansas).
SubstitutionsMissouri Department of Conservation gives gizzard shad as the preferred prey where present, with golden shiners, bullheads and sunfish substituting. Substitution is system-specific and depends on what the water holds.
Diet capacity is not proof that a hatch or prey event is occurring. Observed current forage still comes from a user observation or Hatch Match.
Through the year
Season
Spring
- Where they sit
- Shallow vegetated backwater, sloughs, oxbows, ditches and weedy margins as water warms; weed edges, inside weedlines and wood in still water.
- Movement
- Adults move into shallow vegetated water. Nesting runs from about April into early June across the sourced range.
- Cover
- Dense aquatic vegetation and wood.
What that changesThe reviewed still-water families that match a cover-oriented ambush predator over and along vegetation are horizontal retrieve, stop-and-go, and live/natural bait suspension. Nest guarding is not converted into a targeting cue.
What would count against it
- treating nest-guarding behaviour as a targeting cue
- using nesting cover as holding water
Spring nest-guarding period. Nests, guarding males and the guarded fry school are excluded from target guidance.
Summer
- Where they sit
- Vegetated lakes, swamps, oxbows and river backwaters. Still water: weed edge, inside weedline, wood, basin and inlet. Flowing water: eddy, side channel, submerged wood, deep pool and undercut bank.
- Depth
- Missouri Department of Conservation: deeper water in daylight, shallow water to feed at night.
- Feeding
- Ambush feeding on fish, with crayfish, frogs and insects taken opportunistically.
- Temperature
- Warm, often poorly oxygenated water is tolerated because the gas bladder functions as a lung. Surface air-gulping is expected in stagnant conditions and is a respiratory act.
- Cover
- Dense vegetation, weedy shallows and submerged wood.
- Light
- Nocturnal feeding is the pattern the agency accounts describe; daylight is spent deeper and in cover.
What that changesStill water: bottom contact, slow drag and stop-and-go worked along weed edges, inside weedlines and wood. Flowing water: cross-current retrieve and stationary bait around eddies, side channels and submerged wood.
What would count against it
- reading surface air-gulping as a surface feeding event
- assuming daylight shallow-water occupancy against the sourced day/night depth split
Spawning · Spring, Early summer
Late-spring spawning occurs in shallow vegetated nests built and guarded by males; nest and fry-guarding behavior is not a target cue.
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
- One long, low dorsal fin with more than 45 rays running over half the back — not two separate dorsal fins.
- Anal fin is short, less than about a quarter the length of the dorsal fin. This is the standard agency separation from northern snakehead, whose anal fin runs roughly two-thirds the dorsal length.
- Pelvic fins sit well back, under the dorsal fin, rather than beneath the pectorals as in snakehead.
- Head is broad, rounded and scaleless; body scales are smooth-edged.
- A pair of short barbels near the nostrils, and strong sharp teeth in the jaws.
- A dark spot at the upper base of the tail. In males it carries a bright orange or yellow halo; in females the halo is faint or absent.
- No chin barbel and only one dorsal fin, which separates it from burbot — burbot has a conspicuous chin barbel, two dorsal fins, and pelvic fins set ahead of the pectorals.
- Average adult length
- Most adults 15–27 in (Missouri Department of Conservation, Indiana DNR). Arkansas account gives an average near 20 in (50 cm).
- Common angling size
- Agency accounts put the great majority of adults in the 15–27 in band at 1–5 lb; fish above that occur but are not typical.
- Typical weight
- 1–5 lb for most adults (Missouri Department of Conservation, Indiana DNR).
- Maximum documented
- USGS gives a maximum of 109 cm (about 43 in). Angling records include 21 lb 8 oz (South Carolina, 1980), 19.0 lb (Florida state record) and 17 lb 15 oz (North Carolina state record).
- Longevity
- Contested. State accounts commonly give roughly 10–12 years in the wild, but a 2022 otolith-ageing study concluded that free-living bowfin exceed 30 years. Treat published maximum ages as unsettled.
What it gets confused with
- Northern snakehead (Channa argus)
- Snakehead has a long anal fin (about two-thirds the dorsal fin length), pelvic fins set beneath the pectorals, and a long, pointed, flattened head. Bowfin has a short anal fin (under a quarter the dorsal length), pelvic fins set back under the dorsal, and a broad rounded head. Wisconsin DNR publishes this three-way key.
- Burbot
- Burbot has two distinct dorsal fins, a conspicuous barbel under the chin, and pelvic fins ahead of the pectorals. Bowfin has one continuous long dorsal fin, no chin barbel, and rearward pelvic fins.
- Eyespot / emerald bowfin (Amia ocellicauda)
- Recognised as a separate species in 2022. Mississippi and Ohio basin and Great Lakes populations are Amia ocellicauda; Atlantic-slope populations remain Amia calva. Missouri Department of Conservation separates them on colour (mottled olive-green vs. reddish-brown) and eyespot prominence. Do not assume an account written before 2022 describes the taxon in front of you.
What follows from all of that
Presentation families
Flowing water
Stationary bait
Hold a scent or food form in one feeding station and wait for a fish to move to it.
- anchor the presentation
- keep bait in the pocket
- detect takes without sweeping
- refresh often
What it asks of the tackle
- Depth control
- High
- Sensitivity
- Moderate
- Casting distance
- Short
- Weight range
- 1/4–1 oz
- Cover resistance
- High
- Line visibility
- Moderate
- Retie frequency
- High
Cross-current retrieve
Represent mobile prey crossing or holding near a current boundary.
- horizontal travel
- intermittent pause
- depth retention
- controlled acceleration
What it asks of the tackle
- Depth control
- Moderate
- Sensitivity
- Moderate
- Casting distance
- Moderate
- Weight range
- 1/8–3/8 oz
- Cover resistance
- Moderate
- Line visibility
- Low
- Retie frequency
- Moderate
Pulse / jig
Lift and drop a compact bait so it occupies a pocket, seam, or head without leaving the water column.
- short lift
- controlled drop
- stay in the pocket
- repeat on the same piece
What it asks of the tackle
- Depth control
- High
- Sensitivity
- High
- Casting distance
- Short to moderate
- Weight range
- 1/8–3/8 oz
- Cover resistance
- Moderate
- Line visibility
- Low
- Retie frequency
- High
Stillwater
Stop-and-go
Imitate injured or hesitating prey by mixing travel with pauses that hold the bait in the strike zone.
- travel
- pause
- keep depth on the pause
- restart without jumping the band
What it asks of the tackle
- Depth control
- High
- Sensitivity
- High
- Casting distance
- Moderate
- Weight range
- 1/8–3/8 oz
- Cover resistance
- Moderate
- Line visibility
- Low
- Retie frequency
- Moderate
Bottom contact
Keep a bait on or just above the substrate along a break, flat, or inside a weed edge.
- feel bottom
- drag or hop
- pause on the break
- stay in contact
What it asks of the tackle
- Depth control
- High
- Sensitivity
- High
- Casting distance
- Moderate
- Weight range
- 1/8–1/2 oz
- Cover resistance
- High
- Line visibility
- Low
- Retie frequency
- High
Subsurface slow-roll
Roll a bait just under the surface or just over the weed tops without breaking them.
- barely subsurface
- steady roll
- tick the tops
- speed just enough to stay up
What it asks of the tackle
- Depth control
- Moderate
- Sensitivity
- Moderate
- Casting distance
- Moderate to long
- Weight range
- 1/4–3/4 oz
- Cover resistance
- High
- Line visibility
- Moderate
- Retie frequency
- Moderate
Live / natural bait suspension
Present a natural food form with enough life or scent to hold in a station without looking mechanical.
- keep it alive or fresh
- match the holding depth
- minimize hardware bulk
- detect without pulling it away
What it asks of the tackle
- Depth control
- High
- Sensitivity
- High
- Casting distance
- Short to moderate
- Weight range
- As light as conditions allow
- Cover resistance
- Moderate
- Line visibility
- Low
- Retie frequency
- High
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.
Bowfin often leave deeper cover along low-light edges; reinforce prey/cover mechanics without treating respiratory surface gulping as feeding.
When
Submerged wood, Weed edge, Inside weedline, Wood, Side channel, Inlet · Low light or Night
Moves up
Stop-and-go, Subsurface slow-roll, Bottom contact, Live / natural bait suspension, Cross-current retrieve, Stationary bait
Reviewed 2026-08-27
Where every sentence came from
Sources
Agency
Missouri Department of Conservation field guide, bowfin / emerald bowfin species account
Used for identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-26.
Agency
North Carolina Wildlife Resources Commission species account, bowfin
Used for identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-26.
Agency
Indiana DNR Division of Fish and Wildlife, bowfin (Amia calva) fact sheet
Used for identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-26.
Agency
Florida Fish and Wildlife Conservation Commission freshwater species profile, bowfin
Used for identification; behaviour; season. Read 2026-08-30, next check 2026-11-26.
Agency
Pennsylvania Natural Heritage Program factsheet, bowfin (Amia calva)
Used for behaviour; forage. Read 2026-08-30, next check 2026-11-16.
Agency
Texas Parks and Wildlife Department bowfin species account
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
Agency
Used for identification. Read 2026-08-30, next check 2026-11-26.
Agency
Wisconsin DNR identification sheet: snakehead, bowfin or burbot — know the difference
Used for identification. Read 2026-08-30, next check 2026-11-26.
Agency
USGS Nonindigenous Aquatic Species species profile, Amia calva (maximum size, feeding)
Used for identification. Read 2026-08-30, next check 2026-11-26.
Agency
USGS Nonindigenous Aquatic Species species profile, Amia calva
Used for forage. Read 2026-08-30, next check 2026-11-29.
Peer reviewed
Used for behaviour; season. Read 2026-08-30, next check 2026-11-16.
Peer reviewed
Used for identification. Read 2026-08-30, next check 2026-11-26.
Synthesis
Encyclopedia of Arkansas (CALS) bowfin entry
Used for behaviour; forage. Read 2026-08-30, next check 2026-11-16.
Synthesis
Freshwater fish life-history synthesis for bowfin
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
Synthesis
Encyclopedia of Arkansas (CALS) bowfin entry — vernacular names, size records, Arkansas life history
Used for identification. Read 2026-08-30, next check 2026-11-26.
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.