Environmental DNA Assay for the Detection of the American Bullfrog () in the Early Stages of the Invasion in the Ebre Delta.

The American bullfrog () is considered to be one of the most harmful invasive species. In the Iberian Peninsula, this species had been cited occasionally until the year 2018, when appeared in the Ebre Delta, and, for the first time, it started breeding in a territory of the Peninsula. Using environmental DNA (eDNA) analysis and visual surveys, the American bullfrog invasion in the Ebre Delta was monitored across two consecutive years (2019-2020).

Severe, rapid and widespread impacts of an Atlantic blue crab invasion.

The Atlantic blue crab (Callinectes sapidus) has rapidly invaded coastal environments in the western Mediterranean, but there is no consistent assessment of its impacts yet. We use interviews and long-term data series in the Ebro Delta (NE Spain) to: i) characterise the evolution of the blue crab invasion; and ii) identify its impacts. The blue crab was first recorded in 2012, but its expansion started around 2016, with an exponential increase in abundance between 2017 and 2018.