Texas Species Suitability Map – Exotic Ranch & Wildlife Network

Species: Species guide → Documented populations Directory ranches

Suitability:Excellent (80–100)Good (65–79)Fair (50–64)Marginal (35–49)Poor (<35)Documented populationDirectory ranches (count)

This is a modeled, inferred suitability score — not a guarantee and not a record of where animals live. It combines real county climate and terrain data with each species' native climate/habitat class from cited sources. Thresholds are our rubric choices (shown below), informed by the sources; only a few have direct numeric support (giraffe <50 °F barn rule; nilgai freeze mortality). Good management (shelter, feed, water) can extend range; a high score does not remove legal, disease or fencing requirements.

Scoring rubric

Each county gets 0–3 points per factor; weighted average → 0–100.

Factor (weight)	Data	Scoring by species class
Cold / heat (×3)	NOAA nClimDiv county Jan mean minimum & Jul mean maximum, 1991–2020 average	Cold-sensitive (tropical/subtropical native): Jan min ≥45 °F=3, 38–45=2, 32–38=1, <32=0 (score capped at Marginal if 0). Giraffe: max 1 point; always capped at Marginal because AZA/USDA require a heated barn below a 50 °F average. Cold-hardy: 3 (2 if Jul max >96 °F). Cold-climate natives (elk, red deer, ibex): Jul max ≤90 °F=3, ≤95=2, ≤98=1, else 0. Highveld (black wildebeest): Jan min ≥28 °F=3 else 2.
Moisture (×2)	NOAA nClimDiv county annual precipitation, 1991–2020	Arid: <15 in=3, 15–25=2, 25–35=1, >35=0. Semi-arid: <22=3, 22–30=2, 30–40=1. Savanna: 20–35=3, 15–45=2, else 1. Moist woodland: ≥35=3, 28–35=2, 18–28=1. Water-dependent: ≥35=3, 25–35=2, 15–25=1. (Humidity data not included; rainfall used as the wetness proxy.)
Vegetation (×2)	US EPA Level III ecoregion (county centroid)	Ecoregion matched to habitat type: brush/browse, open grass, mixed savanna, forest, desert, rocky. 3 = close match, 2 = partial, 1 = weak, 0 = mismatch (desert species outside arid regions).
Terrain (×1.5, only where relevant)	USGS 3DEP elevation (Elevation Point Query Service), relief = max−min of ~13 sample points per county	Climbers (aoudad, ibex, mouflon): ≥800 ft=3, 400–800=2, 200–400=1, else 0. Open-plains species: <300 ft=3, <600=2, else 1. Others: not weighted.

Levels: Excellent ≥80 · Good 65–79 · Fair 50–64 · Marginal 35–49 · Poor <35. Click any county for its factor breakdown.

Species basis & sources

Data sources