Frégate–Denis–Aride Predator Eradication & Seychelles Magpie-Robin Recovery

By the 1970s the Seychelles magpie-robin (Copsychus sechellarum) had collapsed to a single remnant population — as few as 16 to 23 birds, depending on the source — confined to Frégate Island, after introduced rats and feral cats had wiped it out everywhere else in the archipelago.

From 1990, BirdLife International began a translocation programme, later coordinated by Nature Seychelles through the Seychelles Magpie Robin Recovery Team (SMART): each release required the target island to first be cleared of rats and cats and put under biosecurity. Birds were moved to Cousin Island (1994), Cousine Island (1995), Aride Island (2002) and Denis Island (2008). In parallel, the Island Conservation Society ran a separate 2005-2009 programme, funded by the French Global Environment Facility, that eradicated rats on North Island, Conception Island and the main islands of Cosmoledo Atoll.

The combined effect of predator removal, habitat restoration and translocation is one of the best-documented island bird recoveries in the Indian Ocean: published census data put the population at 244-248 birds across five islands by 2012 (Frégate 115, Cousin 38, Cousine 31, Aride 24, Denis 36-40); more recent Nature Seychelles reporting puts the total nearer 500. The species was downlisted by the IUCN from Critically Endangered to Endangered as the recovery took hold, one of only 32 bird species reclassified positively worldwide between 1988 and 2008.

A caveat from the underlying science: a 2022 genomic study (Cavill et al., Ibis) found extremely low genetic diversity across all five island populations, a legacy of the 1970s bottleneck that numeric recovery alone does not resolve — continued genetic and demographic monitoring is recommended.

Read the full analysis: https://natureseychelles.org/seychelles-wildlife/endemic-bird-species/seychelles-magpie-robin/