PrimeBite Fishing Northern Pike Research & Methodology

Northern Pike — Research & Methodology (v1)

Last updated: 2026-02-15

This page documents the variables we use for Northern Pike (v1), the open-access URLs behind each driver, verbatim quotes, and what is research-backed vs calibrated. We do not publish proprietary weights, caps, or equations.

How it works (overview)

Northern Pike (v1) is a freshwater all-day rating (no Major/Minor bite times). We combine moon phase (new/full peak), wind speed (positive within observed range), and a small dusk calibration. Research chooses the drivers; we calibrate weights and curve shape to map into 1.0–5.0. Exact values are proprietary.

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:

• Single location: One small lake (25 ha), Kleiner Döllnsee, north-east Germany (N52°59′, E13°34′).
• Single season: Data from 27 May to 17 September 2005 only.
• Protected environment: The lake was protected from any commercial or public recreational fishing during the study—unlike typical multi-use waters.
• Limited generalizability: The authors note that “a substantial amount of variation in catch rates remained unexplained” (Fisheries Research 105, 2010, p.116).

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: wind adjustment capped at the observed range from the study (exact mapping proprietary).

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 a small dusk boost is applied (exact formula proprietary).

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)

• Major/Minor solunar position windows (“bite times”): disabled for Pike until/unless we find verified open-access evidence that Pike respond to these position-based windows.
• Night-vs-day “night preference”: not used; Kuparinen (2010) compares daytime vs dusk, not night activity.
• Precipitation / pressure: disabled for Pike in v1 (see the app repo factcheck for the Kuparinen p-values and the conservative decision).

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/.

• Civil twilight: sunset → sun’s center 6° below the horizon (FAA/UCCS definition PDFs cached in the app repo; see docs/PIKE_VARIABLES_FACTCHECK.md section D2).
• Moon phase vs illumination: phase position (0..1) is not the same thing as illuminated fraction (0..1). Pike’s pike-newfull model uses phase position (see docs/PIKE_VARIABLES_FACTCHECK.md section D1).