Reintroduction of the Eurasian red squirrel into two urban parks in Portugal

Summary

Eurasian red squirrels vanished from Portugal by the sixteenth century as farming and naval logging destroyed their forest habitat, and only recolonized the north and centre of the country from the 1980s onward. In the 1990s, managers at two urban parks, the Botanic Garden of the University of Coimbra and Parque Biologico de Gaia, reintroduced squirrels mainly to enhance visitor experience and environmental education rather than for strict conservation reasons. Coimbra released 12 squirrels from Madrid in 1994 with one year of supplementary feeding, while Gaia released 12 from France in 1997 followed by three reinforcements of 40 pairs from France and the Netherlands through 2001, backed by continuous feeding and veterinary support. Neither population was monitored for 15 to 20 years, until a 2013 survey using transects, food surveys and public attitude interviews found the Coimbra population had crashed to an estimated two individuals, while the Gaia population remained stable at around 47. Squirrels at both sites favoured oak-dominated forest patches for nesting, and managers reported positive public reaction despite being unable to measure it directly, though road kill was recorded at both parks. The project is rated partially successful. Long-term persistence at Gaia shows aesthetic reintroductions can work, but the Coimbra decline argues for the same standardized monitoring and planning used in conservation-focused reintroductions.