DOI: 10.5061/dryad.fn2z34ttz
title: Directed endozoochorous dispersal by scavengers facilitate sexual reproduction in otherwise clonal plants at cadaver sites

description: The regeneration niche of many plant species involves spatially and
 temporally unpredictable disturbances, called recruitment windows of
 opportunity. However, even species with clear dispersal adaptations such
 as fleshy berries may not successfully reach such elusive regeneration
 microsites. Ericaceous, berry-producing species in the northern hemisphere
 demonstrate this dispersal limitation. They are said to display a
 reproductive paradox owing to their lack of regeneration in apparently
 suitable microsites despite considerable investment in producing large
 quantities of berries. Cadavers generate vegetation-denuded and
 nutrient-rich disturbances termed cadaver decomposition islands. Cadavers
 attract facultative scavengers with considerable capacity for
 endozoochorous seed dispersal. We hypothesize that cadaver decomposition
 islands facilitate recruitment in berry-producing ericaceous species due
 to endozoochorous dispersal directed towards favorable microsites with low
 competition. We examined seedling establishment within a permanent,
 semi-regular 10 × 10 m grid across an ungulate mass die-off on the
 Hardangervidda plateau in southeastern Norway. Competing models regarding
 the relative importance of factors governing recruitment were evaluated,
 specifically cadaver location (elevated seed rain) and microsite
 conditions (competition). We found that cadaver decomposition islands did
 facilitate seedling establishment, as cadaver density was the best
 predictor of seedling distribution. Other important factors governing
 seedling establishment such as percentage cover of soil and vascular
 plants alone were inadequate to explain seedling establishment. Synthesis:
 This study provides a novel understanding of sexual reproduction in
 species with cryptic generative reproduction. The directed nature of
 endozoochorous dispersal combined with long-distance dispersal abilities
 of medium to large vertebrate scavengers towards cadavers allows plants to
 exploit the advantageous but ephemeral resource provided by cadaver
 decomposition islands.
description: The textfile contains data collected in 67 0.5*0.5 survey plots
 covering the area of a reindeer mass die-off (N=323) on the mountainous
 plateau of Hardangervidda in Southeastern Norway. Of the 67 survey
 plots, 59 are distributed in a semi-regular 10 × 10 m grid supplemented by
 8 survey plots superimposed over the area of highest cadaver
 density. 'Point_X' and 'Point_Y'
 are standardized coordinates for
 northing and easting (retained units in meters) for survey
 plots. 'Seedling' is count data of
 ericacuous seedlings (bilberry, <i>Vaccinium
 myrtillus</i>;<i> </i>bog bilberry, <i>V.
 uliginosum</i>; lingonberry, <i>V.
 vitis-idaea; </i>crowberry, <i>Empetrum nigrum</i>).
 Functional group cover (CovPlant, CovBryophyte, CovLichen,
 CovStone, CovCadaver) refers to the total cover
 of vascular plants, bryophyte, lichen, soil, stone and persistent cadaver
 remains estimated to the nearest 5 % within survey plots.
 'CadDen' refers to a cadaver kernel density, followed by a
 numeric indicating the search radius (meters) of the density estimator.
 'CadDist' refers to the distance of each survey plot to the
 nearest cadaver.