Other freshwater · Freshwater
Lake sturgeon
Acipenser fulvescens
Long-lived native sturgeon of large lakes and river systems in central and eastern North America; populations recover slowly from overharvest and habitat fragmentation.
Also called sturgeon, rock sturgeon.
- Flowing water
- Stillwater
- 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
Lake sturgeon harvest and angling are heavily regulated and differ sharply by jurisdiction. Verify current regulations before treating this biological record as a legal fishing opportunity.
Where this applies Great Lakes and central/eastern North American jurisdictions with sharply different sturgeon seasons and rules.
The reviewed context, unedited
Regulated-context record. Verify current season, legal methods, harvest status, size limits, tags, and closed spawning areas before acting on the reading.
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 Lake sturgeon there are 21 of them.
Named by a reviewer
18Somebody looked for this and wrote down that they did not find it.
- Behaviour
Nobody has sourced:
- diel activity pattern — no source reached established one, which is the main reason this record is partial
- an adult thermal preference or avoidance study; the temperature numbers reached are reproductive
- current-facing and velocity selection outside the spawning context
- clarity, cold-front, water-level and angling-pressure responses
- territoriality and aggression — not described in any source reached
- the telemetry findings come from one system (Lake Champlain) and may not generalise to riverine populations
- Identification
Nobody has sourced:
- regional / vernacular names — no agency source reached supplied a list
- a field key separating lake sturgeon from shovelnose sturgeon where the two overlap
- sexual dimorphism outside of size-at-maturity
- spawning coloration
- Forage
Nobody has sourced:
- young-of-year and juvenile diet as distinct entries — the one quantitative study reached found no ontogenetic separation and the agency accounts do not break diet out by life stage
- seasonal diet emphasis
- prey size shifts with fish size
- how large a share of the diet small fish and eggs actually represent; USFWS names them without quantifying them
- Season
Nobody has sourced:
- riverine seasonal habitat use — the seasonal structure here comes almost entirely from one lake telemetry study, which is why this record is partial
- tailwater use, which the catalog lists as river holding for this species but which no source reached documents
- light sensitivity and diel habitat shifts
- a seasonal feeding-intensity or thermal-activity curve for adults
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 Lake sturgeon 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- Deep pool
- Run
- Current break
- Pool tail
- Tailwater
Stillwater
5 reviewed holding classes- Basin
- Drop-off
- Rocky shoreline
- Submerged hump
- Inlet
DepthStrong benthic association, often in deeper main-channel or lake-bottom habitat with seasonal movements between feeding and spawning areas.
Moving waterBottom-oriented in large rivers and lakes; outside spawning movement, adults commonly use deep runs, channels, and current-influenced benthic habitat.
LightBottom orientation and depth reduce the importance of surface light; low light can support movement but substrate and flow dominate habitat use.
Thermal band
Temperature
No reviewed temperature band
Nobody publishes a preferred or active temperature range for Lake sturgeon 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
Not a schooling species. The overlapping home ranges the telemetry work reports are shared habitat use, not shoaling. The dense congregations described in the agency accounts are spawning behaviour, which is treated as conservation context here and is not located or described further.
A toothless benthic suction feeder. The fish drags its barbels lightly over the bottom to detect prey, then extends its protrusible mouth and takes the food in with a mouthful of sediment, expelling the debris through the gills. Braun et al. (2018) place it as the top predator of the benthic food web in the system they studied, with no direct competition from congeners for its preferred prey.
Not resolved. The sources reached do not establish a diel activity pattern for lake sturgeon; 'mixed' is entered as the least-committing value rather than as a finding. Treat this field as unsourced and see gaps.
Seasonal activitySpawning migration runs from late April to early June (Wisconsin DNR) or mid-April to late May (Michigan DNR). Larvae drift from spawning areas in June (COSEWIC). Izzo et al. (2022) found comparable juvenile and adult home-range sizes in spring and summer, smaller juvenile ranges than adult ranges in fall, and the reverse in winter.
Temperature-driven behaviourThe best-sourced thermal numbers are reproductive rather than behavioural. Wisconsin DNR gives spawning starting at 53°F under high flow or 58–59°F under low flow; Michigan DNR gives 55–64°F. COSEWIC gives successful incubation between 10–18°C, optimal hatching at 14–16°C, deformity and mortality at 18–20°C, and lethal conditions above 20°C for embryos. The catalog preferred band of 50–66°F is consistent with those spawning numbers but is not itself corroborated by an adult thermal-preference study in the sources reached.
Depth movementWisconsin DNR describes the species using lakes with extensive shallow water (less than 30 ft) and deep river pools where bottom organisms are abundant. Izzo et al. (2022) recorded adults overwintering at 6–9 m while over half of juveniles overwintered at 25–40 m and occasionally beyond 40 m; the deepwater sites showed less temperature variability and warmer accumulated degree-days.
Open waterA bottom-oriented fish of lake basins, deltas and deep river pools. The telemetry work reports sandy delta substrate as the shared juvenile-and-adult habitat, with juveniles additionally using deeper bay and main-lake areas that adults did not.
Predator avoidanceWisconsin DNR describes lake sturgeon leaping clear of the water and notes the hypothesis that this may shake off lampreys, since most adults carry one or more old lamprey scars. This is a hypothesis in the source, not an established function.
Spawning (conservation context)Spring spawner. Spawning occurs over rocky substrate in flowing water. The velocity and depth USFWS records for those sites, and the timing of the migration to them, are omitted here: together with the substrate they describe where and when to find a spawning concentration of a species that was very nearly lost. Eggs are adhesive and hatch in five to eight days. Females spawn only once every three to seven years and males every one to two years, so a very small fraction of the population is reproductively active in any year. Spawning areas, staging concentrations and migration bottlenecks are conservation context and are neither located nor described in this record; unnatural flow regimes are documented to delay spawning and hold fish on spawning grounds four to six weeks longer than under natural flow.
Where the general rule stops
- Extreme longevity and late maturity make local population status more important than generic abundance assumptions.
- Spawning migrations and known spawning reefs/riffles are not target layers.
What it can eat
Forage
- Aquatic insects
- Crustaceans
- Mollusks
- Worms / annelids
- Small forage fish
- Eggs
A toothless benthic feeder that locates prey by dragging its barbels over the substrate and takes it by suction along with a mouthful of sediment, expelling debris through the gills. Wisconsin DNR names snails, insect larvae, leeches, small clams and other invertebrates; Michigan DNR names insect larvae, crayfish, snails, clams and leeches; USFWS adds small fish and eggs to that invertebrate list. Braun et al. (2018) quantified diet in one river population as dominated by crayfish (49.1 ± 6.4%) and snails (36.3 ± 5.5%), with all other invertebrate taxa contributing minimally. Capacity is not a current forage event.
- Feeding style
- Mixed
- Feeding zone
- Benthic
By life stage
- Adult
- Benthic macroinvertebrates dominate, with small fish and eggs taken as well.
Ontogenetic shiftBraun et al. (2018) found no meaningful ontogenetic diet shift in the population they studied — juveniles and adults showed similar prey use and minimal separation in carbon and nitrogen isotope signatures, which the authors note is contrary to patterns reported in other sturgeon populations.
SubstitutionsPrey emphasis is system-specific: the Saskatchewan River population studied by Braun et al. ran on crayfish and snails, while COSEWIC attributes historical Assiniboine River abundance to a mayfly-larva food base. Diet follows the benthic invertebrate community of the particular water.
Diet capacity is not proof that a forage event is occurring. Observed current forage still comes from a user observation or Hatch Match. Note also that lake sturgeon feeding is substrate-mediated — the fish detects prey with its barbels on the bottom — so the diet record describes what is in the sediment, not what is in the water column.
Through the year
Season
Winter
- Where they sit
- Basin and drop-off. Adults used a discrete shallow-water (6–9 m) overwintering area and were sedentary; over half of juveniles overwintered deep (25–40 m) on the slope, occasionally beyond 40 m.
- Depth
- Sharply split by life stage — shallow for adults, deep for most juveniles, in the one system studied.
- Movement
- Adults sedentary, with a median 95% home range of 4.6 km². Juveniles ranged more widely (median 7.2 km²) and made long-range movements of 18–34 km in winter and spring.
- Temperature
- Deepwater overwintering sites showed less temperature variability and warmer accumulated degree-days than the shallow sites.
What that changesWhere a jurisdiction permits hook-and-line angling for lake sturgeon — many do not — the feeding mechanics point only to bottom families: stationary bait in flowing water, bottom contact or slow drag in stillwater. The fish finds food by dragging its barbels over the substrate and takes it by suction, so any presentation held off the bottom is outside its feeding mode. Check the water's own rules before anything else.
What would count against it
- generalising this life-stage depth split, which comes from a single lake study, to a river population
- assuming an open season — jurisdictional rules govern
Spring
- Where they sit
- Movement toward spawning areas from late April to early June; shallow delta and shoreline habitat with sandy substrate for fish not spawning. In rivers, run and current-break water over rock.
- Movement
- Spawning migration is the dominant spring movement. Juvenile long-range movements of 18–34 km also occurred in winter and spring.
- Temperature
- Spawning begins at 53°F under high flow or 58–59°F under low flow (Wisconsin DNR); Michigan DNR gives 55–64°F.
What would count against it
- reading the spawning migration as an opportunity
- using spawning substrate as holding water
Spring is the spawning period. Females spawn only once every three to seven years, so the reproductively active fraction of any population is small in a given year and disturbance costs are high. Spawning areas, staging concentrations and migration bottlenecks are not located or described in this record, and no presentation implication is given for this season. Unnatural flow regimes are documented to hold fish on spawning grounds four to six weeks longer than natural flow does.
Summer
- Where they sit
- Basin, drop-off and rocky shoreline in lakes; deep pool, run and pool-tail in rivers. Wisconsin DNR describes lakes with extensive shallow water under 30 ft and deep river pools where bottom organisms are abundant. Sandy delta substrate was the shared juvenile-and-adult habitat in the telemetry study.
- Depth
- Juvenile and adult distributions overlapped substantially in shallow delta water through spring and summer.
- Forage
- Benthic invertebrates — crayfish and snails dominated the one quantified diet study; insect larvae, leeches and small clams appear across the agency accounts.
What that changesSame mechanical constraint as winter, and the same jurisdictional gate: where hook-and-line angling is authorised at all, only bottom families match a barbel-and-suction benthic feeder — stationary bait in flowing water, bottom contact or slow drag in stillwater. Many jurisdictions authorise none.
What would count against it
- treating this as a mid-water or sight-feeding fish
- assuming an open season — jurisdictional rules govern
Fall
- Where they sit
- Delta and basin habitat continues; juveniles concentrated activity on the delta with smaller home ranges (median 5.5 km²) than adults (7.0 km²).
- Movement
- Juvenile home ranges contract relative to adults, reversing in winter.
What that changesUnchanged by season: bottom-contact families only — stationary bait in flowing water, bottom contact or slow drag in stillwater — and only where the jurisdiction authorises hook-and-line angling for the species. Season dates, tag requirements and closures are set locally and are not inferable from this record.
What would count against it
- assuming an open season — jurisdictional rules govern
Spawning · Spring, Early summer
Adults migrate into rocky, swift river habitat to spawn as spring water warms; spawning aggregations are never named as targeting locations.
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
- Five rows of bony, shell-shaped plates (scutes) — two on each side and one along the back — each with a sharp-pointed spur. The plates smooth out with age and are barely visible on old, large individuals.
- Four barbels hang in a row on the underside of the snout just ahead of the mouth and are used to locate food.
- Mouth is toothless, ventral and protrusible for suction feeding.
- Two spiracles (vents) sit on top of the head forward of the gills.
- Body is scaleless apart from the scute rows.
- Heterocercal tail with the upper lobe longer than the lower — a shark-like profile no other fish in its range shares except the other sturgeons and the paddlefish.
- Average adult length
- USFWS gives typical adults at 4–6 ft; Wisconsin DNR notes females mature at about 55 in and males at about 45 in.
- Common angling size
- Jurisdiction-dependent and set by regulation, not by biology. Michigan DNR allows one fish per angler per year, registered within 24 hours, in designated waters only; Wisconsin DNR describes strict bag, size and length-of-season limits and makes sale of flesh or roe illegal. Any size expectation must come from the local rule set, not from this record.
- Typical weight
- USFWS gives typical adults at 30–80 lb.
- Maximum documented
- USFWS gives the largest fish at about 7 ft and 200–300 lb. Wisconsin's state record is 170 lb 10 oz (1979); Michigan's is 193 lb; Wisconsin DNR also cites a 215 lb, 81 in Canadian fish. COSEWIC gives lengths to 3 m and weights to 180 kg.
- Longevity
- USFWS gives most adults at 50–100 years with the oldest around 150; Michigan DNR gives about 55 years typical with individuals over 100 documented; Wisconsin's oldest record was 82 years and COSEWIC gives ages in excess of 100. Wisconsin DNR notes 97% of sturgeon over 30 years old are female. Females mature at 24–26 years and spawn once every four to six years; males mature at about 15 years and spawn every other year or annually.
What it gets confused with
- White sturgeon
- A separate catalog record and a separate range — white sturgeon are a Pacific-drainage species and lake sturgeon a Great Lakes, Mississippi and St. Lawrence species. Where a fish must be assigned, use the jurisdiction's own key rather than this record; the sources reached do not supply a shared field key.
- Shovelnose sturgeon
- Named by Missouri Department of Conservation as the look-alike for the paddlefish and lake sturgeon group in large-river systems. It is a much smaller sturgeon; the sources reached do not give a scute or barbel character separating it from lake sturgeon, so use the jurisdiction's key.
- Paddlefish
- The paddlefish has a long paddle-shaped rostrum roughly one third of its total length, no scutes, and a huge toothless mouth set far back under the head. Lake sturgeon have a conical snout, five rows of bony scutes and four barbels.
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
Bottom-contact drift
Tick or crawl a food form along the substrate through a feeding lane without snagging constantly.
- feel the bottom
- short hops
- reset after hang
- weight just enough
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
Stillwater
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
Slow drag
Move a bait along the bottom slowly enough that it stays in the feeding layer of inactive fish.
- continuous contact
- very slow travel
- pause at changes in bottom
- do not hop out of the zone
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
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.
Lake sturgeon are strongly benthic; reinforce substrate mechanics while targetContext continues to require current jurisdiction verification.
When
Deep pool, Run, Current break, Basin, Drop-off, Submerged hump
Moves up
Stationary bait, Bottom-contact drift, Bottom contact, Slow drag, Live / natural bait suspension
Reviewed 2026-08-27
Where every sentence came from
Sources
Agency
Wisconsin DNR species account: Lake Sturgeon (Acipenser fulvescens)
Used for identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-13.
Agency
Used for identification; behaviour; forage; season. Read 2026-08-30, next check 2026-11-13.
Agency
Michigan DNR Michigan species: lake sturgeon
Used for identification; behaviour; forage. Read 2026-08-30, next check 2026-11-13.
Agency
USFWS species profile: Lake Sturgeon (Acipenser fulvescens)
Used for identification; behaviour; forage. Read 2026-08-30, next check 2026-11-13.
Agency
U.S. Fish & Wildlife Service lake sturgeon species profile
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
Agency
State and tribal lake sturgeon restoration plans
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
Agency
Missouri Department of Conservation field guide: paddlefish (similar-species listing)
Used for identification. Read 2026-08-30, next check 2026-11-13.
Agency
Michigan DNR Michigan species: lake sturgeon (harvest rules and registration)
Used for season. Read 2026-08-30, next check 2026-11-28.
Agency
Used for season. Read 2026-08-30, next check 2026-11-28.
Peer reviewed
Used for behaviour; forage; season. Read 2026-08-30, next check 2026-11-25.
Peer reviewed
Used for behaviour; season. Read 2026-08-30, next check 2026-11-25.
Peer reviewed
Lake sturgeon movement and benthic-feeding literature
Used for habitat, thermal band and presentation families. Read 2026-08-27, next check 2026-11-27.
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.