# Invasive crayfish spread in Europe

> Live situation record from CLSTR: https://clstr.news/situations/invasive-crayfish-spread-in-europe
> Updated: 2026-07-30T12:37:08.000Z. Sources: 7. Developments: 2.

In late July 2026, Dutch authorities confirmed the detection of a ninth invasive river‑crayfish species, the calicotrivierkreeft, through e‑DNA testing, prompting a government‑led working group to assess control measures. Earlier that day, the Dutch Council of State ruled that only the minister could intervene in water‑level decisions for Natura 2000 sites, underscoring the regulatory backdrop for managing ecological impacts.

Within the same timeframe, conservation groups in northern England launched a national recovery programme for the native white‑clawed crayfish, whose populations have collapsed by up to 80 % due to habitat loss, disease and invasive species. Simultaneously, Dutch ecologists reported the presence of the American calico crayfish (Faxonius immunis) in Gelderland, marking the eighth non‑native crayfish established in the Netherlands. Both developments highlight a growing European concern: the rapid expansion of invasive crayfish species threatening freshwater ecosystems, alongside intensified efforts to protect native biodiversity.

The snapshots together trace a pattern of escalating invasive‑species detections in the Netherlands and coordinated conservation responses in the United Kingdom, reflecting broader regional challenges to freshwater biodiversity.

## Timeline

### 2026-07-30: Crayfish Conservation in England and Invasive Species Alert in the Netherlands

England launches a recovery programme for native white‑clawed crayfish, while the Netherlands reports an invasive American calico crayfish, underscoring freshwater biodiversity challenges in Europe.

2 sources. https://clstr.news/cluster/crayfish-conservation-in-england-and-invasive-species-alert-in-the-netherlands

### 2026-07-30: Netherlands water board barred from raising Natura 2000 level as eighth invasive crayfish appears

The Council of State says Utrecht cannot compel a water board to raise a Natura 2000 water level, while Dutch agencies confirm the arrival of an eighth invasive river crayfish, prompting a joint control effort.

5 sources. https://clstr.news/cluster/netherlands-water-board-barred-from-raising-natura-2000-level-as-eighth-invasive-crayfish-appears

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Cite as: Invasive crayfish spread in Europe. CLSTR, https://clstr.news/situations/invasive-crayfish-spread-in-europe