Mammal assemblages recorded by camera traps inside and outside the evacuation zone of the Fukushima Daiichi Nuclear Power Plant accident

Keita Fukasawa1, Yoshio Mishima2, Akira Yoshioka1, Nao Kumada1, Kumiko Totsu1, Takeshi Osawa3, NIES Fukushima Terrestrial Ecosystem Monitoring Team4, Noe Matsushima5, Saeko Terada6, Yui Ogawa7, Hirofumi Ouchi7

1 National Institute for Environmental Studies, , Japan; 2 Rissho University, , Japan; 3 Tokyo Metropolitan University, , Japan; 4 National Institute for Environmental Studies, 16-2 Onogawa, 305-8506, Tsukuba, Japan; 5 Toho University, ; 6 Tamagawa University, ; 7 National Institute for Environmental Studies, 

Corresponding author(s): Keita Fukasawa (fukasawa@nies.go.jp)Yoshio MishimaAkira YoshiokaNao KumadaKumiko Totsu (totsu.kumiko@nies.go.jp)Takeshi Osawa, NIES Fukushima Terrestrial Ecosystem Monitoring Team (ecomoni_fukushima@nies.go.jp)

Received {date}; Revised {date}; Accepted {date}; Published {date}

Citation: Combination of authors, year of data paper publication (in parentheses), Title, Journal Name, Volume, Issue number (in parentheses), and doi of the data paper.

Resource Citation

Fukasawa K., Mishima Y., Yoshioka A., Kumada N., Totsu K., Osawa T.(2016) Mammal assemblages recorded by camera traps inside and outside the evacuation zone of the Fukushima Daiichi Nuclear Power Plant accident. Ecological Research 31(4), 493. doi:10.1007/s11284-016-1366-7 10.15468/k2fy9c

Abstract

In 2011, the Fukushima Daiichi Power Plant accident resulted in the evacuation of about 81,000 people from the evacuation zone, which suffered from high levels of radioactive contamination. Large-scale and long-term land abandonment can cause changes in species assemblages. Despite the extensive global attention this incident received, open and spatially-explicit datasets of mammal fauna from Fukushima remain quite limited. We established a continuous monitoring protocol using camera traps for mammals both inside and outside the evacuation zone; this paper presents the dataset. These data represent the monitoring results from 46 camera traps from May 2014 to June 2021, including the location and actuation time of each camera, and the list of video records. After the publication of this initial data paper, we intend to continue monitoring until 2023 and the dataset will be hereafter updated with new observations.

Keywords: Occurrence, Observation, forest, Satoyama, depopulation, carnivore, herbivore, Japan, Occurrence

Data published through GBIF: https://gbif.jp/ipt/resource?r=nies_mafu

Taxonomic coverage

Taxonomic ranks
Class: Mammalia

Spatial coverage

General spatial coverage: Fukushima, Japan
Coordinates: 37°2'13.2''N and 37°47'34.8''N Latitude; 140°33'21.6''E and 140°58'4.8''E Longitude 

Temporal coverage: May 15, 2014 - June 8, 2021

Methods

Method step description: The R (R Core Team 2014) function for tabulating number of events and duration of camera in action by arbitrary intervals is available at Github (https://github.com/ecomoni-fukushima/Conversion-tools-for-camera-trapping-data-in-R).
Study extent description: The study area is the eastern part of Fukushima prefecture, located in northeastern Japan, and is enclosed within the following four sets of coordinates: (37.79275°N, 140.55635°E), (37.79275°N, 140.96821°E), (37.03656°N, 140.96821°E), and (37.03656°N, 140.55635°E) (Fig. 1). The study area contains the evacuation zone, which has been categorized since October 2013 into three subzones: a zone in preparation for the lifting of the evacuation order (≤20 mSv/year, Zone 1), a restricted residence area (20-50 mSv/year, Zone 2), and a difficult-to-return-to zone (>50 mSv/year, after 5 years, the air dose rate will still be >20 mSv/year, Zone 3). We set 46 monitoring sites inside and outside the evacuation zone (5 sites in Zone 1, 7 sites in Zone 2, and 13 sites in Zone 3). All the monitoring sites are located in closed forest.
Sampling description: A trail camera (Trophycam HD, and its succesor models by Bushnell Outdoor Products) is installed at each monitoring site during May 2014 to June 2021. Cameras were adjusted to video mode, and the image resolution was 1280×720 pixels (720p) and the frame rate was 30 fps in daytime mode (visible light imaging) and 18 fps in night-vision mode (infrared monochrome imaging). Although the video length was set to 30 seconds, the camera model number 119776 and the later automatically change the video length to 15 seconds in the night-vision mode due to their specifications. The trigger interval was set to 10-second, but it sometimes took more time to recover actually. Cameras were fixed to tree trunks at a height of about 1 m. Data collection and battery exchange have been conducted biannually. In 2014, the data collection and battery exchange were conducted in October and partially in July. Mammals that appeared in the videos were identified and recorded to the event list. The duration between battery exchanges was defined as the “occasion”, and the start and end times of each occasion for each camera were recorded. The occasion values provide information on the durations for which the camera traps were active, and make it possible to calculate records per unit time. An occasion end time was defined as the time when the last video file was recorded, if a camera was inactive due to battery exhaustion or mechanical failure at the visit.
The sensor cameras used in this study are essentially suitable tools for monitoring medium to large sized mammals (O'Brien et al. 2011). The capture efficiency of small mammals (e.g. rodents and shrews), can be highly sensitive to small variations in the installation of cameras, and we do not recommend treating the data on small mammals belonging to the orders Rodentia, Soricomorpha and Chiroptera as correlative indices of abundance.
Quality control description: All species were identified by the authors or by research collaborators who are mammal experts. If we could not obtain sufficient information for species identification from a video image, we recorded a higher taxonomic level (e.g. order and class) which could be certainly specified. Scientific names followed Ohdachi et al. (Ohdachi et al. 2009) and the Catalogue of Life (http://www.catalogueoflife.org/). Since the camera traps were set at the same location, uncertainties of geographical coordinates were estimated to be smaller than 10m in which species could be recorded and identified.

Datasets

Dataset description
Object name: Darwin Core Archive Mammal assemblages recorded by camera traps inside and outside the evacuation zone of the Fukushima Daiichi Nuclear Power Plant accident
Character encoding: UTF-8
Format name: Darwin Core Archive format
Format version: 1.0
Distribution: https://gbif.jp/ipt/archive.do?r=nies_mafu
Publication date of data: 2024-03-14
Language: English
Licences of use: Creative Commons Attribution (CC-BY) 4.0 License

Metadata language: English
Date of metadata creation: 2016-07-12
Hierarchy level: Dataset

References
O'Brien T, Kinnaird MF, Wibisono HT (2011) Estimation of species richness of large vertebrates using camera traps: an example from an Indonesian rainforest. In: AF O'Connell, JD Nichols, KU Karanth (eds) Camera traps in animal ecology: methods and analyses. Springer, pp. 233-252
Ohdachi SD, Ishibashi Y, Iwasa MA, Saito T (2009) The wild mammals of Japan. Shoukadoh Book Sellers, Kyoto
R Core Team (2014) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL: http://www.R-project.org/ (latest access: Aug. 13 2015)