Bird Survey Around Mida Creek
Citation
Nussbaumer R, Lennox K, Jackson C (2021). Bird Survey Around Mida Creek. Version 1.2. A Rocha Kenya. Sampling event dataset https://doi.org/10.15468/jwnu2e accessed via GBIF.org on 2024-08-24.Description
The initial goal of these surveys was to collect information about the location of Mangrove Kingfishers (Halcyon senegaloides) for a geolocator study. However, as surveys provided richer information, it was decided to publish this dataset on its own.
Each survey refers to a complete presence-only species list (called “event” in the dataset), each recorded over ~1km and during ~1hr. Four surveys were performed successively over a morning from 6am to 10am covering a transect. Each of the 23 transects was repeated once a month (grouping called “session”) from May 2020 to May 2021. The study area covers the habitat between Arabuko-Sokoke Forest and Mida Creek.
Surveys were collected by bird guides from the area (Daniel Kazungu, Juma Badi, Kibwana Ali, Saddam Kailo and Mohammed Ali) and organized by Kirao Lennox, Raphaël Nussbaumer and Colin Jackson from A Rocha Kenya.
Summary statistics: 23 transects, 11 sessions: 11, 873 events (surveys): 873, 29'195 occurrences (sightings), 217 species.
Purpose
(1) Collect standardized data on common species between the forest habitat and the creek/coastal habitat, (2) Collect baseline data with a reproducible protocol in order to assess the change of avifauna over time and (3) Assess the impact of deforestation on the ‘shambas’ (fields/farms).Sampling Description
Study Extent
The Kenyan coast was once a large continuous forest called the Northern Zanzibar-Inhambane coastal forest mosaic, of which Arabuko-Sokoke Forest is the largest remainder of today. Extensively studied, this forest is an area of high endemism and was therefore gazetted as a National Park in the late 1980s. Since then, it has benefited from a hard protection from deforestation and human influence. However, the surrounding habitat has been strongly affected by human and agricultural extensions on what used to be forest land. On the other side of our study area, Mida Creek is a 580 ha tidal marine multi-habitat ecosystem fringed with a diverse assemblage of mangrove species (Ceriops tagal, Rhizophora rnucronata, Bruguiera gyrnnorrhiza, Avicennia marina, Sonneratia alba and Xylocarpus benadirensis). Surveys in this area allow us to study the distribution and abundance of common species not necessarily restricted to a specific habitat (such as forest or mangrove), as well as their association with certain habitats. The transects were defined to cover all habitat types between Arabuko-Sokoke Forest, Mida Creek and the coast. They were designed such that the habitat remains relatively homogeneous during each 1hr survey (i.e. along the forest edge or mangrove edge). In addition, each survey starts and finishes near a main road to facilitate access and early start (6am). See for a map of the transects.Sampling
Each survey is performed by 2 persons. Each survey is designed to last 1 hour, covering a transect of 1km. During a survey, each bird species seen and/or heard is recorded once upon the first encounter (i.e., no count data, just presence/absence) The data is collected with the Birdlasser app, allowing to record the GPS location of the observer at the moment of the observation (i.e., not the bird), the exact time of observation (date and hour) as well as any additional comment. Surveys can be paused if interrupted due to heavy rain or interaction with land owners, for instance. This information is recorded in the dynamicProperties and eventRemarks columns in events. Surveys are performed in clusters of 4, starting at 6am up to 10am. Some remote transects (e.g. Kiperwe Island) required more time, thus surveys were performed until 12pm. The Birdlasser data is then exported in CSV format, collected on A Rocha infrastructure and available at /data/birdlasser_files.Quality Control
Quality control is performed in the Rmarkdown scriptProcesse2GBIF.rmd
(https://a-rocha-kenya.github.io/Bird-Survey-Around-Mida-Creek/Process2GBIF.html).
Protocol: Surveys were discarded if the protocol was not properly followed. This happened mainly at the beginning, before the guides were fully trained. We also deleted surveys when the rain lasted longer than 30 minutes.
Spatial error: Phone GPS errors or sightings entered later at wrong locations were manually identified by plotting all sightings on a map. These locations were interpolated linearly between the surrounding sightings of the same survey.
The column georeferenceVerificationStatus
indicates if such interpolation was performed and georeferenceRemarks
provides the original coordinate.
Species list: All species recorded were manually verified by Raphaël Nussbaumer, Colin Jackson and checked with the guides by Kirao Lennox. The spreadsheet species_lists_validation.xlsx
(https://github.com/A-Rocha-Kenya/Bird-Survey-Around-Mida-Creek/blob/main/data/species_lists_validation.xlsx) was used to record the status (see table below) of each species. In general, each specie was either validated or flagged with an error code. Some errors could be corrected by providing the Equivalent specieID
(e.g., taxonomic issue).
Method steps
-
All the processing steps from the original Birdlasser datafile to the GBIF formatted file are described in the Rmarkdown script
Process2GBIF.rmd
(https://a-rocha-kenya.github.io/Bird-Survey-Around-Mida-Creek/Process2GBIF.html).
Taxonomic Coverages
scientificName
and vernacularName
. The taxonID
and taxonRank
are taken from the eBird/Clements Checklist of Birds of the World: v2019 (https://www.birds.cornell.edu/clementschecklist/download/). See section Sampling Description for explanations on how the taxons were initially recorded in the field and later filtered and matched to these taxonomy lists.
Our dataset contains 217 unique species belonging to 64 families.
-
Avescommon name: Bird rank: class
Geographic Coverages
Bibliographic Citations
Contacts
Raphaël Nussbaumeroriginator
position: Research Associate
A Rocha Kenya
email: raphael.nussbaumer@arocha.org
userId: http://orcid.org/0000-0002-8185-1020
Kirao Lennox
originator
position: Research Scientist
A Rocha Kenya
email: lennox.kirao@arocha.org
userId: http://orcid.org/0000-0002-3548-5787
Colin Jackson
originator
position: Director
A Rocha Kenya
email: colin.jackson@arocha.org
userId: http://orcid.org/0000-0003-2280-1397
Raphaël Nussbaumer
metadata author
position: Research Associate
A Rocha Kenya
email: raphael.nussbaumer@arocha.org
userId: http://orcid.org/0000-0002-8185-1020
Raphaël Nussbaumer
administrative point of contact
position: Research Associate
A Rocha Kenya
email: raphael.nussbaumer@arocha.org
userId: http://orcid.org/0000-0002-8185-1020