DOI: 10.5061/dryad.c59zw3rhb
title: Grazing pressure on grass meadows by red deer

description: Grazing by wildlife on agricultural land is widespread across geographical
 regions, and can cause human-wildlife conflicts due to reduced crop yield
 when the grazing pressure is high. Growing red deer (Cervus elaphus)
 populations in Europe calls for an increased understanding of their
 grazing patterns to mitigate damages. We quantified how red deer grazing
 pressure (grazing presence and grazing level) on agricultural grass
 meadows (n = 60) in Norway varied across multiple spatial scales. We used
 a nested, hierarchical study design transcending from broad scale (meadows
 across the landscape) to intermediate (between nearby meadows) and local
 (within-meadow) scale, allowing us to identify at which scale the
 variation in grazing pressure was strongest. We estimated how grazing was
 determined by broad-scale factors influencing forage availability and
 quality through population density, distance to coastline and differences
 between the first versus second harvest, by intermediate-scale factors in
 terms of meadow management causing differences in botanical composition
 and quality, and by local-scale factors in terms of perceived predation
 risk and disturbance. At broad scale, higher population densities were
 associated with higher grazing pressure, and more grazing occurred before
 the first compared to the second harvest. Intermediate-scale factors
 explained the most variation of grazing pressure from red deer, with
 higher grazing pressure on newly renewed meadows compared to other nearby
 meadows. On local scale, more grazing occurred closer to the forest edge,
 providing cover, and further away from infrastructure, with increased risk
 and disturbance. Overall, our study highlights how drivers of grazing
 pressure on agricultural land vary across spatial scales. Population
 reductions on broader scale may have some effect in reducing the grazing
 pressure, but renewed meadows will nevertheless attract red deer causing
 higher grazing pressure compared to neighbouring meadows. This insight is
 crucial for determining effective mitigation strategies facing rising red
 deer populations across Europe.
description: The dataset was collected by observing the number of grazed grass
 blades on n=60 grass meadows on the Norwegian west coast during two field
 periods of 2021. On each meadow, two parallel transects with a random
 30-70 m distance apart and minimum 10 m from the meadow edges were
 delineated (for each field period). For each transect, vegetational
 assessments were performed 20 times approximately 5 m apart, each time
 within a standard botanical metal frame (50 x 50 cm, divided into four
 sub-squares).  Using a standard botanical frame (50x50
 cm), the number of grazing incidents were counted. The number of grazing
 incidents in every sub-square of the botanical frame were categorised into
 four levels: 0 = no observed grazing; 1 = 1-3 grazing instances, 2 = 4-6
 grazing instances, 3 = ≥7 grazing instances. One grazing incidence is
 counted for each grass blade that is grazed. The mean of this measure of
 grazing quantity was calculated for each sampling square (botanical
 frame), and re-scaled from count data to a distribution from 0-1 (0 being
 no grazing and 1 being highest quantity and degree of grazing, equal to 3
 on the original scale). Vegetation cover assessments and plant height were
 averaged for each transect, and elevation and distance to coastline was
 averaged to meadow level. The variables timothy cover, and the distances
 to coast, buildings, forest edge, and roads, were
 log<sub>e</sub> transformed. Total vegetation cover was
 inversed and square root transformed, and plant height was
 mean-centred.
description: # Grazing pressure on grass meadows by red deer
 [https://doi.org/10.5061/dryad.c59zw3rhb](https://doi.org/10.5061/dryad.c59zw3rhb) This dataset contains data on grazing damages by red deer (*Cervus elaphus*) on grass meadows on the Norwegian west coast (Møre & Romsdal county + southern part of Trøndelag county). Grazing damage was quantified by the number of grazing incidents. On each meadow (n=60, surveyed in two field periods during 2021), two parallel transects with a random 30-70 m distance apart and minimum 10 m from the meadow edges were delineated (for each field period). For each transect, vegetational assessments were performed 20 times approximately 5 m apart, each time within a standard botanical metal frame (50 x 50 cm, divided into four sub-squares), and the number of grazing incidents were counted. The number of grazing incidents in every sub-square of the botanical frame were categorised into four levels: 0 = no observed grazing; 1 = 1-3 grazing instances, 2 = 4-6 grazing instances, 3 = ≥7 grazing instances. One grazing incidence is counted for each grass blade that is grazed. The grazing quantity measure was later averaged for each botanical frame and mean-centred and scaled between 0 and 1.  ## Description of the data and file structure The variables included in the dataset are as follows:  * Meadow1: Categorical. Meadow within a site. Levels = X, Y, Z. * Transekt_no: Categorical. Transect within a meadow. Levels = 1, 2. * Blokk: Categorical. Blocks dividing the study area into similiar sized areas for equal distribution of sampling sites. * SiteNEW: Categorical. Sites within block. Levels = α, β. * Rute_id: Categorical. Id of each observational square (rute = square). The ID is made up of "Block_Site_Meadow_Square". * Meadow_Age1: Categorical. Age of the meadow based on time since last renewal. Levels = New, intermediate, and old. * Exclosure: Categorical. Whether there was an exclosure (from a preestablished experiment) on the meadow or not. Levels = YES, NO. * log.M.ele: Continuous. Mean elevation (in m above sea level) of each meadow, log transformed. * log.M.dc: Continuous. Mean distance to coast (in m) for each meadow, log transformed. * log.timodek: Continuous. Percent coverage og timothy (*Phleum pratense*) in each observational square, log transformed. * sqrt.pantdek: Continuous. Percent coverage og all vegetation in each observational square, square root transformed. * sc.innsaa: Continuous. Percent coverage og cultivated (sowed) vegetation in each observational square, mean-centred. * log.distvei: Continuous. Distance (in m) to nearest public road for each observational square, log transformed. * log.distskog: Continuous. Distance (in m) to nearest forest edge for each observational square, log transformed. * log.boliger: Continuous. Distance (in m) to nearest building for each observational square, log transformed. * dens: Continuous. Population density index of red deer, on municipality level. * sc.hoyde: Continuous. Mean vegetation height for each observational square, mean-centred. * drS.sc: Continuous. Mean grazing damage recorded for each observational square, mean-centred and scaled between 0 and 1.