HydroBASINS lev08 watershed · #7080016010
Bassin de South Fork Stillaguamish River
A watershed (drainage basin) is not a body of water — it is the land area where rainfall converges towards a single river that eventually reaches the sea (or an endorheic basin). Boundaries follow ridgelines.
Crosses 3 administrative regions : Island, Skagit, Snohomish
Sub-basin area
2 352,6km²
Upstream area
2 352,6km²
Discharge
0,04m³/s
Mean elev.
427m
Administrative coverage
3 dept-equivalent regions (GADM L2)
- 1610.9 km²68.3% of basin
- 612.0 km²25.9% of basin
- 106.1 km²4.5% of basin
26 intersecting protected areas
Boulder River
IUCN IbWilderness
167.80 km² overlap
Skagit-Snoqualmie
IUCN VWildlife Area Complex
20.81 km² overlap
Morning Star
IUCN VNatural Resources Conservation Area
15.30 km² overlap
Perry Creek
IUCN IaResearch Natural Area
9.10 km² overlap
Snohomish River Estuary
IUCN Not AssignedEstuary
3.98 km² overlap
Port Susan Bay
IUCN VPrivate Conservation Land
3.91 km² overlap
Lake Twenty-Two
IUCN IaResearch Natural Area
2.79 km² overlap
Long Creek
IUCN IaResearch Natural Area
2.62 km² overlap
Reserve Program
1.59 km² overlap
17 more protected areassorted by overlap area
Reserve Program
1.03 km² overlap
Smoke Farm
IUCN VPrivate Conservation
0.55 km² overlap
Spencer Island
IUCN VLocal Conservation Area
0.41 km² overlap
Riviera
IUCN VEnvironmental System
0.40 km² overlap
Robe Canyon I-II
IUCN VPrivate Conservation
0.34 km² overlap
Grandy Lake Stillaguamish River
IUCN Not AssignedPreserve
0.32 km² overlap
Greater Skagit Delta
IUCN VPrivate Conservation Land
0.30 km² overlap
Us-Wa-151-1
IUCN Not AssignedConservation Easement
0.24 km² overlap
Qwuloolt
IUCN VWetland Preserve
0.14 km² overlap
North Fork Stilliguamish - Hazel Hole
IUCN Not AssignedConservation Easement
0.13 km² overlap
Happy Valley
IUCN Not AssignedForest Preserve
0.10 km² overlap
Easement
0.08 km² overlap
Pragtri Farm
IUCN VLocal Land Trust
0.07 km² overlap
Tipperman
IUCN Not AssignedWetlands Preserve
0.04 km² overlap
Forestry Riparian Easement Program 288
IUCN Not AssignedEasement
0.02 km² overlap
Snohomish
IUCN VCounty Conservation Land
0.01 km² overlap
Local Land Trust
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
4 125 distinct species · 1 116 144 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 30 species (selected proportionally per kingdom among those with at least one documented interaction here) to keep the graph readable. Hover for details, click to explore the full ecosystem of a species.
ℹ️ The territory contains many more species than displayed and all their documented interactions: the graph is intentionally the structural skeleton (top-N species by composite local score, edges filtered by Serrano 2009 disparity filter α=0.2).
Indicateurs du tissu écologique
Tissu écologique de Bassin de South Fork Stillaguamish River : 19 espèces reliées par 76 interactions GloBI sur 3 types (connectance 15.3%, filtre Serrano α=0.2). 13 bulles taxonomiques (cascade genre/famille GloBI, ≥3 espèces).
Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).
Hydroclimate (BasinATLAS lev08)
Mean T°
8,2°C
Annual rain
1 550mm
Moisture idx (CMI)
0,44
Runoff
1 210mm/an
PET
760mm
AET
607mm
Mean slope
11,5°
Water table
477cm
Forest
84%
Crops
7%
Urban
4%
Protected
8%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)