Sister species of the Española Ground Finch (Geospiza conirostris) (Lamichhaney et al., 2015). The largest of the ground finches, and the one with the most robust bill, specialized in eating larger seeds that no other finch is capable of. It could only be confused with the Medium Ground Finch (Geospiza fortis) in extreme individual variations with a larger bill, but it is differentiated because the bill of the Large Ground Finch spans its entire face and continues towards the forehead with the same slope, without a distinct or protruding forehead. It has two subspecies, with G. m. darwini still not scientifically clarified, and some authors propose it as a subspecies of the Genovesa Cactus Finch (Geospiza propinqua) (Jaramillo et al., 2020a).

On July 27, 2023, I observed an adult male Large Ground Finch alongside a female Medium Ground Finch, perched on a fence at the Charles Darwin Research Station, Puerto Ayora, Santa Cruz, showing signs of being notably related. The male flew away, and the female followed behind. This is interesting because De Roy (2022) mentions that both species could hybridize.

Geographic Distribution: The subspecies G. m. darwini inhabits Darwin and Wolf, and the nominal subspecies inhabits all other Galápagos islands except Española (BirdLife International, 2023). Extinct in Floreana (Fessl et al., 2017; BirdLife International, 2023). It is also mentioned as extinct in San Cristóbal (Fessl et al., 2017), but there are some recent records on citizen science platforms that appear to be valid (EcoRegistros, 2023; eBird, 2023). Personally, I believe that since it is a highly trusting species that withstands urbanization, it might have the ability to travel on vessels.

Description extracted from: La Grotteria (2023).

REFERENCES

La Grotteria, J. 2023. Identificación, comentarios y registros personales de pinzones de Darwin. Referencia Orientativa.

 See related literature