After reclassification in 2016, the little vermilion flycatcher (Pyrocephalus nanus) was made a separate species from its now-extinct relative, the San Cristobal vermilion flycatcher (Pyrocephalus dubius). Unfortunately, the same threats that led to their extinction, including invasive species such as rats, threaten the little vermilion flycatcher today. In fact, it is locally extinct on Floreana island, close to extinction on Santa Cruz island and under threat on Isabela island.
Research on the three population sites of little vermilion flycatchers looks to assess the current population sizes and threats to each found that the invasive parasitic fly, Philornis downsi. The fly’s larvae feed on the young of many land birds in Galapagos and are one of the main drivers of population declines. However, in Mina Roja on Santa Cruz, many of the abandoned nests showed few signs of P. downsi infestation, which suggests that this might not be the reason behind low breeding success rates on this island.
The little vermillion flycatcher requires an open area for foraging, one suggestion for the decline is an increase in the invasive raspberry plant (Rubus niveus). This plant creates dense thickets, which prevents successful feeding and is thought to be another cause of the alarming population declines.
Efforts to remove the invasive raspberry plants from Mina Roja on Santa Cruz will increase to allow for the restoration of the Scalesia forest habitat, interspersed with open areas for breeding and foraging. The team will also reduce the pressure from invasive species, including both rats and P. downsii larvae. The latter will be achieved using techniques trialled by the mangrove finch project team, who have increased the number of young birds surviving into adulthood through in nest treatment of P. downsii larvae with insecticide.
To find out more about the project, please visit our blog for project updates.