Zomerganzen - Summering geese management and population counts in Flanders, Belgium

Evento de amostragem
Versão mais recente published by Research Institute for Nature and Forest (INBO) on abr 12, 2021 Research Institute for Nature and Forest (INBO)

Baixe a última versão do recurso de dados, como um Darwin Core Archive (DwC-A) ou recurso de metadados, como EML ou RTF:

Dados como um arquivo DwC-A download 4.831 registros em English (546 KB) - Frequência de atualização: atualmente
Metadados como um arquivo EML download em English (33 KB)
Metadados como um arquivo RTF download em English (25 KB)


Zomerganzen - Summering geese management and population counts in Flanders, Belgium is a sampling event dataset published by the Research Institute for Nature and Forest (INBO). The dataset contains over 3,700 sampling events, carried out since 2009, mostly in the months June and July. The data are compiled from different summering geese related projects, but most data were collected through fieldwork within the framework of the EU co-funded Interreg projects INVEXO (http://www.invexo.eu) and RINSE (www.rinse-europe.eu). Since 2015, data collection is funded by INBO. The dataset includes close to 5,000 presence occurrences, as well as over 15,000 absence occurrences. The sampling protocol for the majority of the occurrences are simultaneous counts. Here, the number of individuals of different geese species in a fixed set of areas is determined. Counts are performed within the same weekend to avoid double counting. Simultaneous counts were organised yearly since 2008 and take place the first weekend after July 15, the best period for monitoring the summering population of geese. These counts are performed by professional INBO employees as well as experienced birdwatchers from Natuurpunt using a standardized field protocol. Data are recorded in a citizen science portal (http://waarnemingen.be/waarnemingen_projecten.php?project=231). However, The dataset also comprises opportunistic field observations from the same portal outside this period. Furthermore, data are derived from management actions, such as fertility reduction (egg shaking and pricking), the use of Larsen traps (for Egyptian goose), and the execution of moult captures. Here, the individuals in the dataset were actually removed from the environment. The aim of the data collection is management follow-up and evaluation. Consequently, caution is advised when using these data for trend analysis, distribution range calculation, niche modeling or other. Issues with the dataset can be reported at https://github.com/LifeWatchINBO/data-publication/tree/master/datasets/zomerganzen-events

We strongly believe an open attitude is essential for tackling the IAS problem (Groom et al. 2015). To allow anyone to use this dataset, we have released the data to the public domain under a Creative Commons Zero waiver (http://creativecommons.org/publicdomain/zero/1.0/). We would appreciate it however if you read and follow these norms for data use (http://www.inbo.be/en/norms-for-data-use) and provide a link to the original dataset (https://doi.org/10.15468/a5ubtp) whenever possible. If you use these data for a scientific paper, please cite the dataset following the applicable citation norms and/or consider us for co-authorship. We are always interested to know how you have used or visualized the data, or to provide more information, so please contact us via the contact information provided in the metadata, opendata@inbo.be or https://twitter.com/LifeWatchINBO.

Registros de Dados

Os dados deste recurso de evento de amostragem foram publicados como um Darwin Core Archive (DwC-A), que é o formato padronizado para compartilhamento de dados de biodiversidade como um conjunto de uma ou mais tabelas de dados. A tabela de dados do núcleo contém 4.831 registros.

Também existem 1 tabelas de dados de extensão. Um registro de extensão fornece informações adicionais sobre um registro do núcleo. O número de registros em cada tabela de dados de extensão é ilustrado abaixo.

Event (core)

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.


A tabela abaixo mostra apenas versões de recursos que são publicamente acessíveis.

Como citar

Pesquisadores deveriam citar esta obra da seguinte maneira:

Devisscher S, Adriaens T, Brosens D, Huysentruyt F, Driessens G, Desmet P (2021): Zomerganzen - Summering geese management and population counts in Flanders, Belgium. v1.6. Research Institute for Nature and Forest (INBO). Dataset/Samplingevent. https://doi.org/10.15468/a5ubtp


Pesquisadores devem respeitar a seguinte declaração de direitos:

O editor e o detentor dos direitos deste trabalho é Research Institute for Nature and Forest (INBO). To the extent possible under law, the publisher has waived all rights to these data and has dedicated them to the Public Domain (CC0 1.0). Users may copy, modify, distribute and use the work, including for commercial purposes, without restriction.

GBIF Registration

Este recurso foi registrado no GBIF e atribuído ao seguinte GBIF UUID: 2b2bf993-fc91-4d29-ae0b-9940b97e3232.  Research Institute for Nature and Forest (INBO) publica este recurso, e está registrado no GBIF como um publicador de dados aprovado por Belgian Biodiversity Platform.


Samplingevent; invasive alien species; summering geese; monitoring; citizen science; Samplingevent


Sander Devisscher
  • Provedor Dos Metadados
  • Originador
  • Ponto De Contato
Research assistant
Research Institute for Nature and Forest (INBO)
Kliniekstraat 25
1070 Brussels
Brussels Capital Region
Tim Adriaens
  • Provedor Dos Metadados
  • Originador
Research Institute for Nature and Forest (INBO)
Kliniekstraat 25
1070 Brussels
Brussels Capital Region
Dimitri Brosens
  • Provedor Dos Metadados
  • Originador
Data liaison officer
Research Institute for Nature and Forest (INBO)
Kliniekstraat 25
1070 Brussels
Brussels Capital Region
Frank Huysentruyt
  • Originador
Research Institute for Nature and Forest (INBO)
Gaverstraat 4
9500 Geraardsbergen
East Flanders
Gerald Driessens
  • Originador
Medewerker vogels en waarnemingen.be
Coxiestraat 11
2800 Mechelen
Peter Desmet
  • Provedor Dos Metadados
  • Originador
Data lab coordinator
Research Institute for Nature and Forest (INBO)
Kliniekstraat 25
1070 Brussels
Brussels Capital Region

Cobertura Geográfica

In the initial stages, data from the simultaneous counts of summering geese were gathered at the level of the two westernmost provinces in Flanders (West Flanders, East Flanders), as these were considered in the Invexo and RINSE project's area. These are provincies with high numbers of summering geese, with several species under management (greater Canada goose, Egyptian goose, greylag goose). Here, a set of counting areas with confirmed presence of geese was selected and maintained as the sample study area over the years. Since 2014, management has been upscaled to other provinces. Therefore, counts are organised at the level of the whole Flanders region since.

Coordenadas delimitadoras Sul Oeste [50,68, 2,54], Norte Leste [51,51, 5,92]

Cobertura Taxonômica

All 20 species (and some subspecies and hybrids) in this dataset belong to the waterfowl family Anatidae. More than 80% of the occurrences are swans and true geese (subfamily Anserinae). Some individuals were not identified to species (e.g. unknown hybrids, eggs).

Reino Animalia (animals)
Filo Chordata
Class Aves (birds)
Ordem Anseriformes
Família Anatidae (ducks, geese & swans)
Espécie Alopochen aegyptiacus (Egyptian goose), Anas platyrhynchos (mallard), Anser albifrons (greater white-fronted goose), Anser anser (greylag goose), Anser brachyrhynchus (pink-footed goose), Anser caerulescens (snow goose), Anser cygnoides (swan goose), Anser erythropus (lesser white-fronted goose), Anser fabalis (bean goose), Anser indicus (bar-headed goose), Branta bernicla (brent goose), Branta canadensis (Canada goose), Branta hutchinsii (cackling goose), Branta leucopsis (barnacle goose), Branta ruficollis (red-breasted goose), Cairina moschata (Muscovy duck), Chenonetta jubata (Australian wood duck), Chloephaga picta (Magellan goose), Cygnus olor (mute swan), Oxyura jamaicensis (ruddy duck)

Cobertura Temporal

Período de tempo em que viveu 2010-06-22 - now

Métodos de Amostragem

This dataset contains data from several types of goose management as well as monitoring data. Management is performed with one of several methods: - Moult captures: during the moulting period (June-July), when the geese tend to congregate on open water, geese are trapped in large numbers with corral traps. - Larsson trap captures: for Egyptian goose (Alopochen aegyptiacus). The data are from a floating Larsson-like trap using a live decoy bird. Traps are checked daily for any caught specimens and bycatch. - Fertility reduction: the eggs are mostly pricked with a nail so the animal remains on the nest, sometimes eggs are shaken to destroy the embryo. Monitoring is performed using the following census method: - Simultaneous counts in summer (1st weekend after 15 July, a date which is set in accordance with the regions surrounding Flanders): multiple volunteers from bird working groups (Natuurpunt vzw) perform simultaneous count (within the same weekend) of a list of the more important goose sites (west and east flanders 2009-2013, Flanders since 2014). Counts are coordinated by the ngo Natuurpunt and a citizen science portal (http://waarnemingen.be/waarnemingen_projecten.php?project=231) is used for standardized data input and feedback to volunteers. Only when a site was completely surveyed for all of these species the observation was given the "Simultaneous count" - sample type. - Counts of geese at moulting sites (June 2012): during one day 8 teams of specialists visited every pond in the province of West-Flanders with a surface area of 5 hectares or more in search of groups of moulting geese. Also big streams where inventoried. - Field observations: These contain occurrences from 2 different sources: (1) counts carried out 3 days prior to or after the simultaneous counts weekend within the borders of any of the sites of intrest. These aren't necessarily completely surveyed for all species and should therefore be treated as loose, opportunistic observations, and (2) counts carried out during the simultaneous counts weekend within the borders of any of the sites of intrest but incompletely surveyed for all the species.

Área de Estudo Flanders. Scope: management evaluation based on management results reporting and standardized monitoring census data. Species: greylag goose, feral domesticated goose, barnacle goose, Egyptian goose, greater Canada goose, other non-native goose species (bar-headed goose, Magellan goose).
Controle de Qualidade The fieldwork is performed by skilled volunteer birdwatchers, often working together within local bird clubs. The NGO Natuurpunt (http://natuurpunt.be) supports the majority of these bird clubs and volunteers, and thereby delivers an important contribution to the project. Quality control on the data was performed by Natuurpunt Studie vzw. Additionally, all the data was validated by experts from the Research Institute for Nature and Forest (INBO).

Descrição dos passos do método:

  1. To allow reliable comparisons between years and areas, the counts are aimed for maximum standardization. Not all areas are counted every year. The aim is a yearly coverage of 65% of the areas. Trend calculations based on these census data therefore requires taking into account area and year effects.

Citações bibliográficas

  1. Adriaens T, Huysentruyt F, Devisscher S, Devos K, Casear J (2010) Simultaantelling overzomerende ganzen in Oost- en West- Vlaanderen. Vogelnieuws 15: 4-11.
  2. Adriaens T, Huysentruyt F, Onkelinx T, Devisscher S, Devos K & Casaer J (2011) Simultaantelling overzomerende ganzen in Oost- en West- Vlaanderen. Vogelnieuws 17, 24-30
  3. Van Daele P, Adriaens T, Devisscher S, Huysentruyt F, Voslamber B, De Boer V, Devos K, Casaer J (2012) Beheer van zomerganzen in Vlaanderen en Zeeuws-Vlaanderen: rapport opgesteld in het kader van het INVEXO - INTERREG project. Rapporten van het Instituut voor Natuur- en Bosonderzoek INBO.R.2012.58, Brussel, Brussel, 162 blz.
  4. Adriaens T, Van Daele P, Huysentruyt F, Devisscher S, Casaer J, Devos K (2012) Junitelling van West-Vlaamse zomerganzen. Vogelnieuws 18, 16-22
  5. Adriaens T, Huysentruyt F, Devisscher S, Devos K, Casaer J (2014) Integrated management of invasive geese populations in an international context: a case study in Belgium & The Netherlands. In : Science for the New Regulation, One day Benelux Conference on Invasive Alien Species. 2/04/14 → 2/04/14 - Ghent, België. https://data.inbo.be/pureadmin/files/6391140/Adriaens_etal_2014_IntegratedManagementInvasiveGeesePopulationsInternationalContext.pdf
  6. Chapter "Canada geese in Flanders urban areas" In: van Ham C, Genovesi P, Scalera R (2013) Invasive alien species: the urban dimension, Case studies on strengthening local action in Europe. Brussels, Belgium: IUCN European Union Representative Office. 103pp. https://portals.iucn.org/library/efiles/documents/2013-027.pdf
  7. Adriaens T, Huysentruyt F, Standaert S (2014) Controlling invasive geese in the RINSE region: A collaborative endeavor. Bridging the Gap: Working together to tackle invasive non-native species in Europe. RINSE closing conference. 23/09/14 → 23/09/14 - Norwich, Verenigd Koninkrijk. https://www.inbo.be/nl/publicatie/controlling-invasive-geese-rinse-region
  8. Adriaens T, Van Daele P, Devisscher S, Huysentruyt F, Voslamber B, De Boer V, Devos K, Casaer J (2013) Integrated management of invasive geese populations in an international context: a case study. IUGB (International Union Of Game Biologists) Congress 2013. 27/08/13 → 29/08/13 - Brussels, België. https://data.inbo.be/purews/files/1156729/O.TL.16_Adriaens.pdf
  9. Adriaens T, Huysentruyt F, Devisscher S, Casaer J (2013) Integrated Management of Invasive Geese Populations in an International Context: A Case Study in Belgium & The Netherlands. 2nd International Congress on Biological Invasions - Biological Invasions, Ecological Safety and Food Security. 23/10/13 → 27/11/13 - Qingdao, China. https://www.inbo.be/nl/publicatie/integrated-management-invasive-geese-populations-international-context-1
  10. Huysentruyt F, Adriaens T, Devisscher S, Casaer J (2013) Evaluation Of A Large Scale Management Strategy For Summering Geese In Flanders And Zealand (Belgium/the Netherlands). The Wildlife Society 20th Annual Conference. 5/10/13 → 10/10/13 - Milwaukee, WI, Verenigde Staten van Amerika. https://www.inbo.be/nl/publicatie/evaluation-large-scale-management-strategy-summering-geese-flanders
  11. Huysentruyt F, Adriaens T, Van Moer K, De Bus K, Casaer J (2014) Catching invasive Egyptian geese (Alopochen aegyptiacus): Evaluation of the optimal deployment season for a floating Larsen trap. Science for the new regulation Abstractbook: BENELUX Conference on invasive species. Boets, P. (ed.). blz. 33 1 blz. https://www.inbo.be/nl/publicatie/catching-invasive-egyptian-geese-alopochen-aegyptiacus
  12. Invexo-Project brochure: 'Minder invasieve planten en dieren, meer biodiversiteit. Invexo-projectbrochure 2009-2012', september 2012. http://www.invexo.be/~/media/Files/Invexo/Invexo20092012ProjectbrochureSept2012.pdf
  13. Adriaens T, Huysentruyt F, Van Daele P, Devos K, Casaer J (2014) Evaluatie bescherming en beheer van ganzenpopulaties. Inhoudsevaluatie van natuurbeleid in landbouwgebied: case vogelbeheer en erosiebestrijding. van Gossum, P. (ed.). INBO.R.2012.50 ed. Brussel: Instituut voor Natuur- en Bosonderzoek, blz. 29-41 13 blz. https://www.inbo.be/nl/publicatie/evaluatie-bescherming-en-beheer-van-ganzenpopulaties
  14. Groom QJ, Desmet P, Vanderhoeven S, Adriaens T (2015) The importance of open data for invasive alien species research, policy and management. Management of Biological Invasions (2015) Volume 6, Issue 2: 119–125 https://doi.org/10.3391/mbi.2015.6.2.02 https://doi.org/10.3391/mbi.2015.6.2.02

Metadados Adicionais

Propósito Impact scoring for established non-native birds in Europe has shown Canada goose (Branta canadensis) to have the highest environmental, economic (agricultural damage) and social impact of all non-native birds species. Among the ecological effects are overgrazing, fouling, trampling of vegetation such as reed beds and meadows, bioturbiation of oligitrophic fens and pathogen transmission. Also, geese cause agricultural damage and nuisance in recreational areas. Management of invasive geese in the region (western Flanders, eastern Flanders, Zeeuws-Vlaanderen) was, until recently, mainly done by egg pricking and hunting. Within the framework of the EU co-funded Interreg projects Invexo and RINSE, the coordination of egg pricking and hunting was enhanced and additional moult captures (n=131) were performed on a larger cross-border scale. Moult captures were very successful for Canada geese, with a total of 7829 caught between 2010 and 2013. Greylag geese (Anser anser), although comparable in density, tended to move away from catching sites during the moulting season. In relation to density, catch success for feral goose (Anser anser f. domestica) was high. Barnacle geese (Branta leucopsis) moult later and were therefore only caught in very low numbers. The reported numbers of Canada geese culled by hunters also increased in the same period with over 7000 birds shot per season. The overall impact of the combined management efforts was assessed by annual simultaneous counts of the geese populations in the region using a fixed sample of counting areas. Trends in the average number of geese per municipality and per year were modelled using gee-GLMs. This showed a significant decrease in the number of Canada and feral goose since the beginning of the projects. In East Flanders, where moult captures were applied most intensively, a significant yearly decrease was noted. Here, the modeled decline was in line with the trend in the absolute numbers of Canada geese which showed a 40 % reduction since 2010. For the species caught in high numbers, the impact was significant over four years, and related to catch effort. Although suggesting a link between moult captures and population numbers this approach would assume other management efforts to be evenly applied over the project area, which was not the case. Moreover, the absolute number of geese in the entire area hardly decreased in the last year. Recent research indicates that Canada geese disperse over large distances within Europe, blurring effects of a local action over the years. Goose captures were performed within the EU co-funded Interreg Invexo (http://www.invexo.eu) (2010-2012) and the Interreg 2Seas project RINSE (http://www.rinse-europe.eu) (2012-2014), which seeks to improve awareness of the threats posed by INNS, and the methods to address them. Future work will be to upscale management and implement adaptive management backed by population models and thorough monitoring. This requires continued investment in prevention, awareness raising and generating public support.
Identificadores alternativos 2b2bf993-fc91-4d29-ae0b-9940b97e3232