PrimeBite Fishing Northern Pike Full Transparency

Northern Pike — Full Transparency (v1)

Last updated: 2026-01-29

This page is designed to leave nothing out: the exact equations, every variable we use, the open-access URLs behind each driver, verbatim quotes (with page pointers where available), and a plain-English explanation of what is research-backed vs what is calibrated.

On this page

The exact math (Northern Pike v1)

Northern Pike (v1) is a freshwater all-day rating: we do not publish Major/Minor “bite times” for Pike because we do not have verified open-access evidence that Pike respond to solunar position windows. 

// Lift-to-rating map (global; PrimeBite standard)
L_total_clamped = clamp(L_total, 0, L_REF)          // where L_REF = 0.28
raw_rating = 1 + 4 × (L_total_clamped / L_REF)      // then clamped to [1.0, 5.0]

// Northern Pike day lift (all-day; no Majors/Minors)
L_total_raw = L_phase + L_weather + L_dusk
L_total = applySeasonalMultiplier(L_total_raw, seasonMult)   // Pike v1: seasonMult = 1.0 (disabled)

rating = liftToRating5(L_total)

Key idea: research chooses the drivers (what matters), then we calibrate the exact sizes and curve shapes so the output is stable, explainable, and consistently mapped into 1.0–5.0.

Study limitations (Kuparinen 2010)

Northern Pike v1 is based on a single open-access study. We disclose the following limitations so users do not assume ratings apply universally:

PrimeBite uses the evidence-backed direction of effects (dusk, wind, new/full moon) from this study and calibrates magnitude to produce a stable 1.0–5.0 day rating. Ratings are relative indicators, not guarantees; they are anchored to this limited dataset.

Variables (what’s research-backed vs calibrated)

Research-backed means the driver/pattern is supported by open-access sources. Calibrated means we chose the exact thresholds/weights/caps to make a stable 1–5 score.

Moon phase (L_phase)

Research-backed: Pike catch rates peak around full and new moon.

Calibrated: the exact curve shape and magnitude used to map that pattern into a 1.0–5.0 score.

Implementation: phaseModel: 'pike-newfull' (phase-position model; peaks at new/full), phaseWeight (calibrated).

Source (open access): Kuparinen et al. 2010 — Fisheries Research (PDF)

“Catch rates of pike were significantly increased … around full and new moon …”

(printed p.111 Abstract; see app repo extracts: docs/_pdf_cache/pike/extracts/_extract_Kuparinen_2010_p1.txt)

Wind speed (L_weather)

Research-backed: within the observed range in Kuparinen (2010), higher wind speed is associated with increased catch rates.

Calibrated: the exact mapping from mph → score adjustment (we use a simple monotonic boost capped at the observed range; no penalty without evidence).

Implementation: pikeWindAdj(windMph) capped at 15.4 mph (Kuparinen’s observed range).

Source (open access): Kuparinen et al. 2010 — Fisheries Research (PDF)

“Catch rates of pike were significantly increased … at … high wind speeds …”

(printed p.111 Abstract; see app repo extracts: docs/_pdf_cache/pike/extracts/_extract_Kuparinen_2010_p1.txt)

Dusk / civil twilight (L_dusk)

Research-backed: Pike catch rates are higher during dusk.

Calibrated: because Pike is an all-day rating (no specific bite-time windows), we apply dusk as a small all-day calibration based on evening civil twilight duration.

Implementation (all-day calibration): compute evening civil twilight minutes, then duskAdj = (minutes / 1440) × duskAlwaysBoost.

Source (open access): Kuparinen et al. 2010 — Fisheries Research (PDF)

“Catch rates of pike were significantly increased … as well as during dusk.”

(printed p.111 Abstract; see app repo extracts: docs/_pdf_cache/pike/extracts/_extract_Kuparinen_2010_p1.txt)

Explicitly not used for Pike (v1)

Key definitions & verification sources

These definitions are not Pike biology claims — they are the astronomy/time definitions required to compute inputs consistently. In the app repo, the cached definition PDFs and extracted quotes live under docs/_pdf_cache/definitions/.

Worked example (simple)

Example day: near new moon + windy conditions + normal dusk duration. Pike’s day rating increases when multiple evidence-backed drivers align (new/full + wind + dusk). 

// Example inputs (illustrative)
moonPhase = 0.00      // new moon (phase position)
windMph   = 12.0      // within observed range
duskMin   = 35        // typical evening civil twilight duration

// Steps
phaseBoost = moonPhaseBoostPikeNewFull(moonPhase)      // 0..1 (peaks at new/full)
L_phase    = phaseLift(phaseBoost, phaseWeight)        // magnitude calibrated
L_weather  = weatherLift(pikeWindAdj(windMph))         // positive within range; capped at 15.4 mph
duskAdj    = (duskMin / 1440) × duskAlwaysBoost        // small
L_dusk     = duskLift(duskAdj)                         // small by design

L_total    = L_phase + L_weather + L_dusk              // seasonality disabled (×1.0)
rating     = liftToRating5(L_total)                    // 1.0..5.0

Model changelog

PrimeBite Fishing — Northern Pike Transparency (v1)