Marshy valley of the Drweca river

IBA Justification

The site was identified as important in 2010 because it was regularly supporting significant populations of the species listed below, meeting ('triggering') IBA criteria.

Populations meeting IBA criteria ('trigger species'):
Species Current IUCN Red List Category Season Year(s) Population estimate at site IBA criteria met
Bean Goose Anser fabalis LC passage 2004-2009 3,300 individuals C7
Greater White-fronted Goose Anser albifrons LC passage 2004-2009 7,000 individuals C7
A4iii Species group - waterbirds n/a passage 2004-2009 5,000-20,000 individuals C4

The current IUCN Red List category may differ from that which was valid at the time of IBA criteria assessment (2010).

IBA Conservation

IBA conservation assessment
Year of assessment (most recent) State (condition) Pressure (threat) Response (action)
2011 unfavourable not assessed not assessed
Was the whole site assessed? State assessed by Accuracy of information
yes population good

State (condition of the trigger species' populations)
Scientific name Common name Reference population Actual population Units % of population remaining Result
Grus grus Common Crane 20 21 breeding pairs 100 favourable
Clanga pomarina Lesser Spotted Eagle 2 1 breeding pairs 50 unfavourable

Response (conservation actions taken for the trigger species and/or their habitats)
Protected-area designation Management planning Other conservation action Result
Not assessed Not assessed Not assessed not assessed
For more information about IBA conservation status, please click here

IBA Protection

Protected area (PA) PA designation PA area (ha) Relationship of PA with IBA Overlap of PA with IBA (ha)
Rzeka Drwęca Rezerwat Przyrody 1,594 protected area overlaps with site 0
Górznieńsko-Lidzbarski Park Krajobrazowy Park Krajobrazowy 27,536 protected area is adjacent to site 0
Drweca Nature Reserve 444 protected area contained by site 1,287
Doliny Drwęcy Obszar Chronionego Krajobrazu 55,552 protected area overlaps with site 3,136
Dolina Drwęcy Site of Community Importance (Habitats Directive) 12,562 protected area overlaps with site 816
Dolina Dolnej Drwęcy Obszar Chronionego Krajobrazu 16,550 unknown 0
Brodnicki Park Krajobrazowy Park Krajobrazowy 16,889 protected area overlaps with site 0
Bagienna Dolina Drwęcy Special Protection Area (Birds Directive) 3,366 protected area overlaps with site 3,136


Habitat (IUCN level 1) Habitat detail Extent (% of site)
Forest Broadleaved deciduous woodland, Native coniferous woodland, Mixed woodland, Alluvial and very wet forest -
Grassland Steppes and dry calcareous grassland, Humid grasslands, Mesophile grasslands -
Wetlands (inland) Standing freshwater, Rivers and streams, Raised bogs, Water fringe vegetation, Fens, transition mires and springs -
Artificial/Terrestrial Highly improved re-seeded landscapes, Arable land, Ruderal land -
For more information about the IUCN Habitat classification, please click here.

Land use

Land-use Extent (% of site)
agriculture -
forestry -
not utilised -
hunting -

Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Marshy valley of the Drweca river. Downloaded from on 22/02/2024.