Data from: Reindeer carcasses modulate vegetation composition and greenness in High-Arctic tundra

Milder winters over High Arctic regions have dramatic impacts on local
biodiversity on Svalbard, with rain-on-snow events directly correlated
with reindeer mortality. Vertebrate carrion can have disproportionately
larger impacts on vegetation in nutrient-limited systems, compared with
warmer biomes. We conducted a ground survey on the cover of five plant
functional groups at paired carcass and control sites and analysed the
relationship between cover and carcass presence with generalised linear
mixed effect models. Vegetation indices from RGB imagery captured by
drones complemented this, assessing plant productivity in terms of
‘spectral greening’. We modelled the relationship between vegetation index
values and carcass distance with generalised additive models. We show that
graminoids capitalised most from carcass presence, whereas bryophytes and
lichen showed decreases in cover. Woody plants and herb covers were not
significantly impacted by carcass presence. The Red Green Blue Vegetation
Index (RGBVI, our proxy for vegetation productivity) decreased locally at
fresh carcasses (i.e. <1 year old) but showed an increase at more
established carcass sites (i.e. >1 year). We show that carcasses
have differential impacts on the plant functional groups of Svalbard’s
tundra and induce a local ‘green-up’ with secondary succession within 2
metres. Given their non-random distribution, carcasses may contribute to
vegetation heterogeneity at landscape scales. This is relevant for
understanding how climate change-induced reindeer mortalities will impact
Arctic tundra composition in the future.