HydroBASINS lev08 watershed · #2080021110
Bassin de la Vilaine
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 2 administrative regions : Loire-Atlantique, Morbihan
Sub-basin area
383,8km²
Upstream area
10 459,3km²
Discharge
168,69m³/s
Mean elev.
45m
Administrative coverage
Hydrographic chain
▼ Drains into
Outlet (drains to ocean / endorheic)
▲ Receives from 2 basins
- Bassin de l'Isac725 km²
- Bassin de la Vilaine78 km²
2 dept-equivalent regions (GADM L2)
- 379.6 km²98.6% of basin
- 5.1 km²1.3% of basin
27 communes (GADM L5)Available for FRA, RWA
- Nivillac52.31 km²93% commune
- Saint-Dolay41.64 km²86% commune
- Péaule39.59 km²100% commune
- Caden37.65 km²99% commune
- Béganne35.14 km²100% commune
- Marzan32.36 km²95% commune
- Limerzel24.89 km²100% commune
- Arzal21.31 km²84% commune
- Férel17.63 km²60% commune
- Allaire15.46 km²37% commune
- Rieux14.76 km²53% commune
- Questembert13.84 km²21% commune
- Camoël6.88 km²47% commune
- Le Guerno5.74 km²60% commune
- Saint-Gorgon5.60 km²94% commune
- Théhillac5.55 km²39% commune
- Herbignac4.83 km²7% commune
- Pénestin3.01 km²13% commune
- Malansac2.95 km²8% commune
- Noyal-Muzillac1.62 km²3% commune
- Muzillac1.04 km²3% commune
- La Roche-Bernard0.45 km²100% commune
- Missillac0.26 km²0% commune
- Saint-Jacut-les-Pins0.16 km²1% commune
- Assérac0.04 km²0% commune
- Pluherlin0.03 km²0% commune
- Fégréac0.00 km²0% commune
9 intersecting protected areas
Marais de Vilaine
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
22.65 km² overlap
Brière
IUCN VRegional Nature Park
5.19 km² overlap
Estuaire de la Vilaine
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
1.44 km² overlap
Baie de Vilaine
IUCN Not ReportedSpecial Protection Area (Birds Directive)
1.44 km² overlap
Chiroptères du Morbihan
IUCN Not ReportedSpecial Areas of Conservation (Habitats Directive)
0.01 km² overlap
Les Rochers du Ruicard
IUCN Not ReportedGeotope Protection Order
0.00 km² overlap
Le Moustoir en Arzal
IUCN Not ReportedGeotope Protection Order
0.00 km² overlap
Biotope Protection Order
0.00 km² overlap
Biotope Protection Order
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
2 297 distinct species · 43 890 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 39 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 la Vilaine : 33 espèces + 6 bulles famille, 89 interactions GloBI documentées sur 5 types (connectance 12.0%, filtre Serrano α=0.2). Les 6 bulles regroupent des espèces visuellement absorbées par famille (≥3 espèces visibles).
Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).
Hydroclimate (BasinATLAS lev08)
Mean T°
11,4°C
Annual rain
811mm
Moisture idx (CMI)
0,05
Runoff
543mm/an
PET
772mm
AET
569mm
Mean slope
2,0°
Water table
155cm
Forest
1%
Crops
56%
Urban
3%
Protected
1%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)