Evento de amostragem

Batumi Raptor Count (BRC) - Autumn migration data

Versão mais recente publicado por Batumi Raptor Count em 16 de Junho de 2020 Batumi Raptor Count
Publication date:
16 de Junho de 2020
Published by:
Batumi Raptor Count
CC0 1.0

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 725 registros em English (13 MB) - Frequência de atualização: atualmente
Metadados como um arquivo EML download em English (17 KB)
Metadados como um arquivo RTF download em English (16 KB)


One of the most important geographical bottlenecks for migrating raptors in the east African-Palearctic migration system is situated between the easternmost tip of the Black Sea and the Lesser Caucasus, just north of Batumi, in the Republic of Georgia (Verhelst et al. 2011).

Since 2008 citizen scientists of the Batumi Raptor Count(BRC) monitor the autumn raptor passage daily from mid August till mid October, collecting also detailed information about the age and sex of focal species. These data are included in the BRC dataset. This dataset offers a unique baseline for monitoring the state of migrant raptor populations in the east African-Palearctic flyway in the 21st century.

Each season a large number of raptors are counted during the autumn migration count. The numbers fluctuate around the million individuals in each season. This dataset represent the data during the 2008-2017 seasons. A detailed description of the BRC migration count protocol, data management strategy, and the open access BRC dataset in GBIF are provided by Wehrmann et al. (2019). This dataset has been used to analyse changes in the abundance and demography of eight abundant raptor species at BRC between 2011-2017. The resulting research paper is currently in 2nd review and will be shared through this webpage immediately upon publication.

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 725 registros.

Também existem 2 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:

Wehrmann J, de Boer F, Benjumea R, Cavaillès S, Engelen D, Jansen J, Verhelst B, Creuwels JCS, Vansteelant WMG (2018): Batumi Raptor Count (BRC) - Autumn migration data. v1.2. Batumi Raptor Count. Dataset/Samplingevent. http://ipt.nlbif.nl/resource?r=brc-autumn_migration_counts&v=1.2


Pesquisadores devem respeitar a seguinte declaração de direitos:

O editor e o detentor dos direitos deste trabalho é Batumi Raptor Count. 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: d19c0287-15ee-45fd-b810-d30e8026a785.  Batumi Raptor Count publica este recurso, e está registrado no GBIF como um publicador de dados aprovado por Netherlands Biodiversity Information Facility.


Occurrence; Autumn migration; raptor; African-Palearctic flyway; monitoring


Quem criou esse recurso:

Jasper Wehrmann
BRC Foundation
Hannah Arendtweg 84
1349CM Almere
Folkert de Boer
BRC Foundation
Hannah Arendtweg 84
1349CM Almere
Wouter Vansteelant
BRC Foundation
Hannah Arendtweg 84
1349CM Almere
Jeroen Creuwels
Data manager NLBIF
PO Box 9517
NL-2300 RA Leiden

Quem pode responder a perguntas sobre o recurso:

Jasper Wehrmann
Folkert de Boer
BRC Foundation
Hannah Arendtweg 84
1349CM Almere

Quem preencher os metadados:

BRC Foundation
BRC Foundation
Dijkgraaf 35
6721 NJ Bennekom

Quem mais foi associado com o recurso:

Niels Raes
Node manager NLBIF
PO Box 9517
NL-2300 RA Leiden
+31 71 7519362
Frank de Miranda
Stichting DuGof
IJskelderlaan 3

Cobertura Geográfica

The bottleneck is situated at the narrowest point between the eastern coast of the Black Sea and the foothills of the Lesser Caucasus, just to the north of the city of Batumi, in the Republic of Georgia.

Coordenadas delimitadoras Sul Oeste [41,684, 41,699], Norte Leste [41,688, 41,802]

Cobertura Taxonômica

Soaring birds and few others such as Roller

Ordem Accipitriformes (Raptors)
Espécie Coracias garrulus (European Roller), Streptopelia turtur (European turtle dove), Ciconia ciconia (White Stork), Ciconia nigra (Black Stork)

Cobertura Temporal

Período de Formação mid Aug to mid Oct annually from 2008 till present.

Dados Sobre o Projeto

Since 2008 citizen scientists of the Batumi Raptor Count(BRC) monitor the autumn raptor passage daily from mid August till mid October, collecting also detailed information about the age and sex of focal species. Counts are focused on high-quality data for monitoring of target species, and for which species we can provide high-quality data useful for trend analyses.

Título Batumi Raptor Counts - Autumn migration data
Financiamento NLBIF partly funded publication and processing of the BRC dataset to GBIF
Descrição da Área de Estudo The two count stations are located on hilltops with unobstructed view facing north into the landscape, and within visible range from each other. Locations are the villages Sakhalvasho and Shuamta, North of Batumi, in the Republic of Georgia, between the easternmost tip of the Black Sea and the Lesser Caucasus.
Descrição do Design Migration counts are performed simultaneously from two count stations to cover the approximately 12km long transect line.

O pessoal envolvido no projeto:

Jasper Wehrman
Ponto de Contato

Métodos de Amostragem

Daily counts from 17st August till 16st October. The daily count period starts at one hour after sunrise and ends two hours before sunset. Counts consisted of continuous monitoring during the count period and recording all occurrences.

Área de Estudo The villages Sakhalvasho and Shuamta, North of Batumi, in the Republic of Georgia.
Controle de Qualidade Counts are conducted by experienced and less experienced bird-watchers that volunteer to count at least two weeks. Count-coordinators screen, select and schedule volunteers such that each station can be staffed by a team consisting of one coordinator and 6 to 12 counters, depending on migration intensity, diversity and also counter availability. We try to enter records always immediately to enable the double count detection in later phase. Digital photography has become an important tool to aid identification of easily confused species.

Descrição dos passos do método:

  1. At the end of each day count-coordinators go through the records to check for major errors (using simple criteria such as large flocks of rare birds, or specific age and sex combinations), and where possible correct them by discussing these observations with their daily count team. Observations that are suspect due to insufficient information (for example, a large eagle cannot be identified without being aged) are degraded to a less specific level (large eagle spec.).
  2. At the end of each season the data is verified with an automated script in the open source R software (R Core Team 2017) that validates each single record, ensures count protocol integrity and changes the identification of the species-level of those records with insufficient information.
  3. An important final step in the production of the NLBIF data product is to detect all double counts in the overlapping count zones between the two stations. An automated procedure written in R detects potential double counts in different spatial and temporal windows for different species.

Citações bibliográficas

  1. Wehrmann J, de Boer F, Benjumea R, Cavaillès S, Engelen D, Jansen J, Verhelst B, Vansteelant WMG (2019) Batumi Raptor Count: autumn raptor migration count data from the Batumi bottleneck, Republic of Georgia. ZooKeys 836: 135-157. https://doi.org/10.3897/zookeys.836.29252
  2. Verhelst B, Jansen J, Vansteelant WMG (2011) South West Georgia: an important bottleneck for raptor migration during autumn. Ardea 99: 137–146. https://doi.org/10.5253/078.099.0203

Metadados Adicionais

Information about killed and injured birds during the Autumn raptor monitoring is given in the extension ExtendedMeasurementOrFact. Due to a technical error (which is under review at GBIF) this extension does not automatically link data in this extension with the occurrence dataset. Therefore these data will not be shown at the GBIF portal. However, these data can be retrieved from DwCA in the file "extendedmeasurementorfact.txt".

Propósito Monitoring the abundance, demography and timing of migrant raptors and selected threatened species in the East African-Palearctic flyway. In addition the data collected may be useful for studying the influence of weather on diel and seasonal migration dynamics of soaring birds.
Descrição da manutenção Dataset is annually maintained.
Identificadores alternativos d19c0287-15ee-45fd-b810-d30e8026a785