VU
Galapagos Rail Laterallus spilonota



Justification

Justification of Red List Category
This species is restricted to a small range on just a few islands. The population is declining owing to the ongoing effects of introduced plants, herbivores and predators and the continuing destruction and degradation of habitat, which have already led to local extinctions. The species is therefore listed as Vulnerable.

Population justification
The population was estimated to number 5,000-10,000 individuals by Rosenberg (1990), and repeat surveys on Santa Cruz Island in 2000 gave broadly similar results. This roughly equates to 3,300-6,700 mature individuals.

Trend justification
The species is undergoing a slow decline. The rate of decline was extrapolated from a decline in detections of 9% (c.f. 1986-1987 surveys) during 2000 surveys on Santa Cruz (Gibbs et al. 2003). By 2007, the decline was steeper (Shriver et al. 2011). Therefore, the population decline is here tentatively placed in the band 1-19% over ten years.

Distribution and population

Laterallus spilonota is endemic to the Galápagos Islands, Ecuador, where it occurs on a number of islands including Pinta, Fernandina, Isabela (on Sierra Negra, Wolf, Darwin, Alcedo volcanos), Santiago, Santa Cruz and Genovesa. It is considered common in the highlands of Santiago, Santa Cruz and Sierra Negra (south Isabela) and smaller though stable or increasing populations occur on Wolf, Darwin, and Alcedo volcanos and on Fernandina (J. Gibbs in litt. 2007). The Pinta population is recovering after goat eradication. Survey work on Santa Cruz suggests a slight population decline since baseline surveys in 1986-1987 (Gibbs et al. 2003). The population on San Cristóbal, Baltra and Floreana are probably extinct (H. Vargas and F. Cruz in litt. 2000, Dvorak et al. 2017, 2019, Jiménez-Utzcátegui and Ortíz-Catedral 2019).

Ecology

It inhabits grass and forest of mesic regions in the highlands, where it occurs in deep thickets and dense ground-cover (Taylor and van Perlo 1998), although it is rarely found in mangroves (Wiedenfeld 2006). It appears to favour areas with freshwater pools, and avoids short, herbaceous vegetation (Rosenberg 1990). Although historically known from coastal mangroves, it has largely abandoned this habitat for unknown reasons (Taylor and van Perlo 1998). It appears tolerant of human-modified habitats, such as agricultural land, but avoids grazed, short-grass meadows (Rosenberg 1990). It feeds mainly on invertebrates and seeds (Franklin et al. 1979, Harris 1982).

Threats

This species is probably vulnerable to introduced predators such as rats (predation on nests and fledglings potentially the biggest threat, D. Wiedenfeld in litt. 2012), cats, dogs and pigs, given its weak flying ability. Short-eared Owl Asio flammeus and Barn Owl Tyto alba may be natural predators (Rosenberg 1990, Taylor and van Perlo 1998). Habitat destruction as a result of grazing by introduced herbivores (notably goats, cattle and horses) is probably the principal explanation for the possible extinction on San Cristóbal and Floreana (Rosenberg 1990; H. Vargas and F. Cruz in litt. 2000; Dvorak et al. 2017, 2019). The invasion of the highlands of Santa Cruz by exotic Cinchona may lead to a reduction in the fern and sedge vegetation types it favours (Gibbs et al. 2003). Further threats include climate change and severe weather events, which may negatively affect habitat availability, and collisions with vehicles (Jiménez-Utzcátegui et al. 2019).

Conservation actions

Conservation Actions Underway
Most of the archipelago is under national park protection, including much of the species's remaining natural habitat. Localised control of introduced predators is ongoing (Taylor and van Perlo 1998) and the UNDP 'Galapagos Invasive Species' project took place between 2001-2007. Goats have been eradicated from Pinta, north Isabela and Santiago, and on Santiago a programme to eradicate pigs has been successfully completed (H. Vargas and F. Cruz in litt. 2000, Cruz et al. 2005). The islands were declared a World Heritage Site in 1979.

Conservation Actions Proposed
Conduct standardised surveys on all range islands to assess the total population size. Monitor population trends through regular surveys. Study the impacts of predation and habitat degradation by alien species. Restore plant communities on Santiago and north Isabela (Rosenberg 1990, A. Tye in litt. 2000). Monitor the expansion of invasive Cinchona in the highlands of Santa Cruz (Gibbs et al. 2003). Control invasive species (Jiménez-Utzcátegui et al. 2019). Establish environmental education programmes and awareness campaigns to reduce disturbance on inhabited islands (Jiménez-Utzcátegui et al. 2019).

Identification

15-16 cm. Small, dark rail. Dark grey-black head, neck and breast. Brown upperparts with small white spots (when breeding). Dark grey-brown underparts with barred black-and-white undertail. Brown legs, black bill, red eye. Female similar but possibly paler throat. Similar spp. Paint-billed Crake Neocrex erythrops is larger, barred on flanks, lacks white spotting and has red legs and green-and-red bill. Voice Variable. Territorial call, fast chi-chi-chi-chirroo descending on the last note, also descending trill and various rattles, squeaks, hisses, cackles and warbles.

Acknowledgements

Text account compilers
Hermes, C.

Contributors
Benstead, P., Cruz, F., Fessl, B., Gibbs, J., Jiménez-Uzcátegui, G., Mahood, S., McClellan, R., Pople, R., Sharpe, C.J., Symes, A., Temple, H., Tye, A., Vargas, H. & Wiedenfeld, D.


Recommended citation
BirdLife International (2021) Species factsheet: Laterallus spilonota. Downloaded from http://www.birdlife.org on 06/03/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 06/03/2021.