Species → European Bison
European Bison
Bison bonasus
What if it disappeared?
Impact High10,807 seedlings belonging to 178 different plant taxa germinated from bison dung, direct proof of a broad-spectrum seed-dispersal role — but with an unexpected twist: captive bison, partly fed by humans, dispersed an even greater seed diversity than free-ranging bison.
DocumentedDetail
Jaroszewicz, B., Pirożnikow, E. & Sagehorn, R. (2009). Endozoochory by European bison (Bison bonasus) in Białowieża Primeval Forest across a management gradient. Forest Ecology and Management, 258(1), 11-17.
Based on 74 dung samples collected in Białowieża Forest. The study compares three management regimes (captive, semi-wild, wild) and shows the diversity gradient of dispersed seeds follows management intensity rather than naturalness — a reminder that supplementary feeding given to captive bison can, paradoxically, enrich their disperser role rather than diminish it.
On plots heavily grazed by bison, up to 57 species of carabid beetles (ground-dwelling predatory beetles) were recorded, compared to just 32 to 35 on comparable ungrazed plots — bison grazing doesn't just change the vegetation, it also reshapes the insect community living on the forest floor.
DocumentedDetail
Schwerk, A., Klich, D., Wójtowicz, E. & Olech, W. (2021). Impact of European bison grazing (Bison bonasus (L.)) on species and functional traits of carabid beetle assemblages in selected habitats in Poland. Biology, 10(2), 123.
Based on three bison populations in Poland. More than 21,000 individuals in total were identified across the free-ranging and captive sites combined. The clearest effect isn't on carabid abundance but on their functional traits (size, diet, flight ability), suggesting the bison acts by filtering which types of carabids thrive rather than simply changing how many there are.
All of today's European bison descend from a founding stock of just 12 individuals, and roughly 80% of their genes come from only two of them — genetic diversity so reduced that it remains unknown whether it limits the species' ability to occupy its full range of habitats and fully perform the ecosystem-engineer role it held before its near-extinction.
InsufficientDetail
The average inbreeding coefficient of current populations is around 17%, a level associated elsewhere in the animal kingdom with reduced fertility and lower disease resistance. The ecological studies cited in this profile measure what today's bison does, not what a genetically more diverse bison might do beyond that.
Documentation
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Jaroszewicz, Pirożnikow & Sagehorn (2009) — Endozoochory by European bison in Białowieża Primeval Forest across a management gradient, Forest Ecology and Management
Accessed August 10, 2026
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Schwerk et al. (2021) — Impact of European bison grazing on species and functional traits of carabid beetle assemblages in selected habitats in Poland, Biology
Accessed August 10, 2026
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IUCN Red List — Bison bonasus, statut et estimation de population
Accessed August 10, 2026
Last verified: August 14, 2026