Nieuwkoopse Plassen & De Haeck

IBA Justification

The site was identified as important in 2016 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
Purple Heron Ardea purpurea LC breeding 2011-2015 133-174 breeding pairs B1i, C6
Black-headed Gull Larus ridibundus LC breeding 2011-2015 4,506-4,524 breeding pairs B3
Sedge Warbler Acrocephalus schoenobaenus LC breeding 2011-2015 825-857 breeding pairs B3

The current IUCN Red List category may differ from that which was valid at the time of IBA criteria assessment (2016).

IBA Conservation

IBA conservation assessment
Year of assessment (most recent) State (condition) Pressure (threat) Response (action)
2018 not assessed high high
Was the whole site assessed? State assessed by Accuracy of information
yes unset medium

Pressure (threats to the trigger species and/or their habitats)
Threat level 1 Threat level 2 Timing Scope Severity Result
Human intrusions and disturbance recreational activities happening now some of area/population (10-49%) moderate to rapid deterioration high
Pollution excess energy - noise pollution happening now majority/most of area/population (50-90%) moderate to rapid deterioration high
Residential and commercial development tourism and recreation areas happening now small area/few individuals (<10%) moderate to rapid deterioration low
Transportation and service corridors flight paths happening now whole area/population (>90%) slow but significant deterioration high

Response (conservation actions taken for the trigger species and/or their habitats)
Protected-area designation Management planning Other conservation action Result
Whole area of site (>90%) covered by appropriate conservation designation A comprehensive and appropriate management plan exists that aims to maintain or improve the populations of qualifying bird species The conservation measures needed for the site are being comprehensively and effectively implemented high
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)
Nieuwkoopse Plassen & de Haeck Site of Community Importance (Habitats Directive) 2,008 is identical to site 2,000
Nieuwkoopse Plassen & De Haeck Special Protection Area (Birds Directive) 1,986 is identical to site 2,000
Nieuwkoopse Plassen & De Haeck Natuurbeschermingswet 2,008 is identical to site 0
Nieuwkoopse Plassen Nature Conservation Law 1,139 protected area contained by site 1,127
De Meije Nature Reserve 39 protected area contained by site 39
De Haeck Nature Reserve with Management Subsidy 11 protected area contained by site 10
De Haak Natural Monument 60 protected area contained by site 60


Habitat (IUCN level 1) Habitat detail Extent (% of site)
Wetlands (inland) Standing freshwater, Water fringe vegetation -
Artificial/Terrestrial Highly improved re-seeded landscapes -
For more information about the IUCN Habitat classification, please click here.

Land use

Land-use Extent (% of site)
fisheries/aquaculture -
water management -
hunting -
nature conservation and research -
tourism/recreation -

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Nieuwkoopse Plassen & De Haeck. Downloaded from on 01/12/2023.