West European hedgehog (Erinaceus europaeus) records in Great Britain from four citizen science surveys analysed in Wembridge et al. West European hedgehog (Erinaceus europaeus) decline in Great Britain: evidence from multiple national scale surveys. Ecology and Evolution (submitted)

Field details within files:

BBS_data.csv

Gridref: Ordnance Survey grid reference (Ikm2 grid square);

year: survey year

hhog_C: detection type is count (1 – yes, 0 – no);

hhog_D: detection type is dead (1 – yes, 0 – no);

hhog_F: detection type is field sign (1 – yes, 0 – no);

hhog_S: detection type is seen on additional vists (1 – yes, 0 – no);

hhog_L: detection type is local knowledge (1 – yes, 0 – no);

hhog_U : detection type is unknown (1 – yes, 0 – no);

hhog: presence/absence of hedgehogs

 GBW_data.csv

Site: uniquely identifies a survey site;

year: survey year

week: week number of year (i.e., 1–52)’

count: maximum weekly count’

hhpres: presence/absence of hedgehogs;

north: British National Grid northing value of survey site;

east: British National Grid northing value of survey site;

nmammals: number of mammal species recorded

LwM-data.csv

LwM: observations of hedgehog at sites within the built environment (predominantly domestic gardens) from sightings or field signs, collected from 2003 to 2024. Data identify location and date of observations; total observation time for year x site combination; percentage surface cover of vegetation types; and site features that are present.

usi!: uniquely identifies survey site

site!

year!: survey year

season!: spring, autumn, other

From 2003 to 2019 inclusive, observations were recorded in a single 13-week period starting on the Monday closest to 01 April. Weeks run Monday to Sunday (corresponding to ‘spring’). In 2020,observations were recorded in two 13-week periods, the first starting on Monday 30 March (‘spring’), and the second, on Monday 31 August (‘autumn’). From Monday 29 March 2021, constraints on when data were collected were removed (i.e., records could be submitted for any week). Since then, the survey has run throughout the year.

ndawn: number of weeks with observation effort at dawn

nday: number of weeks with observation effort during the day

ndusk: number of weeks with observation effort at dusk

nnight: number of weeks with observation effort during the night

‘Dawn’ is defined as one hour before or after sunrise; ‘day’, as one hour after sunrise to one hour before sunset; ‘dusk’, as one hour before sunset to one hour after sunset; ‘night’, as one hour after sunset to one hour before sunrise.

Nall: total number of weeks with observation effort

sumDawn: total observation effort at dawn (minutes)

sumDay: total observation effort at day (minutes)

sumDusk: total observation effort at dusk (minutes)

sumNight: total observation effort at night (minutes)

For each period (e.g., dawn, day, etc.), observation time was recorded as one of five categories: less than a minute; 1-10 minutes; 11-30 minutes; 31-60 minutes; and 60+ minutes. To sum effort across weeks, the mid-value of these categories was used.

nshhog: number of weeks with hedgehog signs

nwhhog: number of weeks with hedgehog sightings (maximum counts)

sumhhog: sum of weekly maximum counts

grass!: percentage cover of the survey site that is grass

shrub!: percentage cover of the survey site that is shrubs

tree!: percentage cover of the survey site that is trees

conc!: percentage cover of the survey site that is concrete/gravel/paving

shed!: percentage cover of the survey site that is shed/hut/building

flow!: percentage cover of the survey site that is flowerbed/cultivated

wild!: percentage cover of the survey site that is untended/’wild’

siteshed: presence of a shed on the site

sitepond: presence of a pond on the site

sitebat: presence of a bat roost box on the site

sitehhog: presence of a hedgehog nest box on the site

sitebird: presence of a bird nest box on the site

sitecomp: presence of a compost pile on the site

sitepile: presence of a wood pile on the site

sitebtab: presence of a bird table on the site

sitebbath: presence of a bird bath on the site

sitbfeed: presence of a bird feeder on the site

siteofeed: presence of a other feeder on the site

siteoriver: presence of a water course on the site

MoR_data.csv

bservations of west Eurpean hedgehog casualties recorded on road journeys from 2001 to 2013. Data identify location and date; distance surveyed; end- and start locations of journey; number of hedgehogs; and survey platform (paper-based or digital).

Field details:

journey : uniquely identifies a record;

date: journey date;

miles: journey distance (mi);

north: British National Grid northing value of journey start point;

east: British National Grid easting value of journey start point;

endnorth: British National Grid northing value of journey endpoint;

endeast: British National Grid easting value of journey endpoint

n_hedgehog: number of hedgehogs recorded;

source: paper; phone (mobile device); online (webpage)

year: journey year