Data from: Northern pikas experience reduced occupancy due to surrounding human land use despite the occurrence of suitable microclimates
Data files
Feb 16, 2024 version files 8.76 KB
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Pika_occupancy_microclimate_TSakiyama.csv
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README.md
Abstract
Aim: Despite warming temperatures, some species are found persisting at the trailing edge of their distribution. Microclimates provided by complex topography are considered a key factor in these cases of range stationarity, buffering stress from exposure to warming and enabling persistence. However, for species with trailing-edges located in human-modified landscapes, refugial conditions provided by microclimates could be disrupted by human activities. Here, we aimed to understand the determinants of trailing-edge occupancy for a small lagomorph found in rocky patches harboring cool microclimates.
Location: Hokkaido Island, Japan
Taxon: Northern pika (Ochotona hyperborea)
Methods: We surveyed the occupancy of northern pikas across a wide elevational gradient (350–2200 m) for two consecutive summers. Ambient air and microhabitat (i.e., rock interstices) thermal conditions were measured to assess their relationship. We then analyzed their effects on occupancy at two nested spatial scales: (1) whole-distribution, and (2) at identified trailing-edge sites where we explored the effects of microclimates and surrounding human activities (i,e., distance to nearest road and area of human land use such as plantation forests or agricultural fields).
Results: Overall, rock interstices exhibited cooler conditions than ambient air with temperature differences of 1–2 ºC. The overall distribution of northern pikas was affected by both mean ambient temperature and microhabitat availability, with warmer (lower elevation) sites with less microhabitats corresponding to the trailing edge of its distribution. Interestingly, trailing edge occupancy patterns were best explained by the negative effect of surrounding human land despite the existence of suitable microclimates in the rocky patches.
Main conclusions: Our findings suggest that the local refugial conditions supported by cool microclimates are likely to be disrupted by the effects of human land at the larger landscape scale. This result highlights the importance of considering the effects of human activities and landscape alteration for effective microrefugia conservation. --
README: README
This file was generated on 2024-02-03 by Tomoki Sakiyama
https://doi.org/10.5061/dryad.k98sf7mc9
GENERAL INFORMATION
1. Title of Dataset:
Data from: Northern pikas experience reduced occupancy due to surrounding human land use despite the occurrence of suitable microclimates
2. Author Information
Corresponding Investigator
Name: Tomoki Sakiyama
Institution: Graduate School of Environmental Science, Hokkaido University, Japan
Email: wisdom.tree.1994@gmail.com
Co-investigators
Name: Jorge Garcia Molinos
Institution: Arctic Research Center, Hokkaido University, Japan
3. Date of data collection:
2021-2022
DATA & FILE OVERVIEW
1. Description of Dataset
The data was generated to analyze the occupancy of northern pikas in Hokkaido, Japan at two nested spatial scales: (1) at whole-distribution scale to define the trailing edge; and (2) at trailing edge scale to explore the effects of microclimates and human modification of the landscape (distance to nearest road and area of human land-use).
2. File list
- Pika_occupancy_microclimate_TSakiyama.csv
3. DATA-specific information for Pika_occupancy_microclimate_TSakiyama.csv
- Column A (Year): Survey year
- Column B (Site): Site ID
- Column C (Ambient_mean): Mean ambient temperature, unit: degrees Celsius
- Column D (Ambient_range): Mean ambient thermal range, unit: degrees Celsius
- Column E (Interstice_mean): Mean interstice temperature, unit: degrees Celsius
- Column F (Interstice_range): Mean interstice thermal range, unit: degrees Celsius
- Column G (Rock_interstice): Rock-interstice availability, unit: percentage
- Column H (Distance_road): Distance to the closest road, unit: meter
- Column I (Area_landuse): Area of human land-use within 3-km radius, unit: square kilometer
- Column J (Detection_sesison1): Detection of occupancy during survey session 1, 0: absent, 1: present, NA: survey not conducted
- Column K (Detection_sesison2): Detection of occupancy during survey session 2, 0: absent, 1: present, NA: survey not conducted
- Column L (Detection_sesison3): Detection of occupancy during survey session 3, 0: absent, 1: present, NA: survey not conducted
- Column M (Detection_sesison4): Detection of occupancy during survey session 4, 0: absent, 1: present, NA: survey not conducted
- Column N (Detection_sesison5): Detection of occupancy during survey session 5, 0: absent, 1: present, NA: survey not conducted
- Column O (Detection_sesison6): Detection of occupancy during survey session 6, 0: absent, 1: present, NA: survey not conducted
- Column P (Date_sesison1): Julian date of survey session 1, NA: survey not conducted
- Column Q (Date_sesison2): Julian date of survey session 2, NA: survey not conducted
- Column R (Date_sesison3): Julian date of survey session 3, NA: survey not conducted
- Column S (Date_sesison4): Julian date of survey session 4, NA: survey not conducted
- Column T (Date_sesison5): Julian date of survey session 5, NA: survey not conducted
- Column U (Date_sesison6): Julian date of survey session 6, NA: survey not conducted