Search

The diet of feral cats Felis catus on Santa Luzia, Cape Verde Islands, was studied. A total of 147 prey items were identified during the analysis of 26 scat groups collected during the summer of 2010. House mouse Mus musculus was the most important prey, both in percentage of biomass and number of preys consumed (89.7% and n= 117, respectively). Reptiles were the second most important prey, represented by one skink species (Chioninia stangeri) and an unidentified gecko species. The remainder of the identified prey consisted of one bird species (Passer iagoensis) and one undetermined Tettigoniidae species (Insecta). No endangered species were identified in scats of this introduced predator, but future surveys must be carried out to further avoid threats to the island's biodiversity. Foi estudada a dieta de gatos assilvestrados Felis catus na ilha de Santa Luzia, Cabo Verde. Foram identificadas 147 presas de um total de 26 dejectos recolhidos no Verão de 2010. A presa mais importante, tanto em percentagem de biomassa como em número de presas consumidas, foi o rato doméstico Mus musculus (89.7% e n= 117, respectivamente). Os répteis foram a segunda presa mais importante, maioritariamente lagartos (Chioninia stangeri), bem como de uma espécie não identificada de osga. Outras presas identificadas foram uma ave (Passer iagoensis) e uma espécie não identificada de Tettigoniidae (Insecta). Não foi detectada nenhuma espécie com estatuto de ameaça na dieta deste predador introduzido, porém outras monitorizações futuras deverão ser implementadas para evitar ameaças à biodiversidade desta ilha.

Feral cats have been directly responsible for the extinction of numerous species on islands worldwide, including endemic species of mammals, birds and reptiles. The diet of feral cats in the main habitats of the Canary Islands, as generally occurred on oceanic islands, is mainly composed of introduced mammals, and native species of birds, reptiles and insects. The impact of feral cat upon the endangered species was assessed by evaluating their relative abundance in the cats' diet and by considering their current conservation status. A total of 68 different preys were identified at species level in all studies carried out in the Canary Islands (5 mammals, 16 birds, 15 reptiles and 32 invertebrates). From all the species preyed by feral cats in the Canary Islands, only four of them are considered threatened by the IUCN Red List of Threatened Species: one endemic bird Saxicola dacotiae and three endemic giant lizards, Gallotia simonyi, Gallotia intermedia, and Gallotia gomerana. Although some efforts on management control have been carried out, it is necessary to enforce these conservation activities on those areas of Tenerife, La Gomera and El Hierro where giant lizards are still present. Furthermore some local areas where endangered bird species are highly predated should be protected. Nevertheless, it is important to take into account the presence of other introduced species such as rats, mice or rabbits in order to avoid problems derived from the hyperpredation process and mesopredator release effect. Thanks to Rafael Riera who support data from Gran Canaria Island control programmes financed by the Cabildo Insular de Gran Canaria and the Canary Government. This contribution has been carried out during the project GL2004-04884-C02-01/BOS financed by the Spanish Ministry of Science and the European Union.

Distribution, status and conservation of the Houbara Bustard Chlamydotis undulata fuertaventurae Rothschild & Hurtert, 1894, in the Canary Islands, November-December 1994. This paper presents the results of census of the Canarian Houbara, which for the first time the total area occupied by this subspecies, Houbaras were detected only in Fuerteventura, Lanzarote and Graciosa. A total of 379 birds were recorded (33 from vehicles, 16 outside the transects, and a minimum of 330 inside the censusing belt), from which we estimated a total population of 527 birds: 18 in Graciosa, 268 in Lanzarote and 241 in Fuerteventura. Although the species scems to reach in the Canarian archipelago the highest density recorded for its whole geographical distribution, this island population is threathened by current loss and alteration of their habitat., Distribución, estatus y conservación de la Avutarda Hubara Chlamydotis undulata fuertaventurae Rothschild & Hartert, 1894, en las islas Canarias (noviembre-diciembre 1994). En el presente trabajo se presentan los resultados de un censo que cubre por primera vez toda el área de distribución de la Avutarda Hubara Canaria. Se detectaron hubaras en Fuerteventura, Lanzarote y Graciosa, contabilizándose un total de 379 ejemplares, 33 desde vehículos, 16 fuera de los transectos y un mínimo de 330 dentro de los transectos. Se ha estimado una población global constituida por 527 aves: 18 en Graciosa, 268 en Lanzarote y 241 en Fuerteventura. Probablemente, la densidad de aves registrada en la población canaria es la más elevada que se conoce para la especie. No obstante, la degradación y la destrucción del hábitat amenazan seriamente la conservación de esta subespecie insular., We are very grateful to K. W. Emmerson (Ornistudio S. L.) for his information on previous censuses, and to P. Jordano for his statistical assistance. Jacinto Barquín helped us with the mapping programs. D. Brooks revised and improved an early draft of the manuscript. We also thank the Instituto Nacional de Meteorología (Canarias Orientales). This work was supported by the Viceconsejería de Medio Ambiente of the Canary Island government.

In this study we present a review on the diet of the feral cat on the Canary archipelago, providing the first data from the reliet laurel forest (Garajonay National Park). Among the 403 prey items identified in this habitat, rats were most numerous followed by reptiles. A total of 1.047 scat groups has been studied in the lat eight years from the main habitats of the Canaries. Most of the 2.963 prey items identified represent introduced mammals (rabbit, Oryctolagus cuniculus; mouse, Mus cf.musculus and rat. Rattus sp.). These prey were commonly captured in most habitats with the exception of high mountain scrub. In this habitat, reptiles were taken instead introduced mammals. They were also more commonly included in the diet from open grpund and open forest than from the denser forest. Birds were more frecuently consumed in the forest than in open areas. Anthropods appeared in significant proportions in the scats from habitats where these items reached high numbers. The results indicate that the diet of feral cats clearly varies according to the different habitats., The authors would like to express their gratitude to Ornistudio S. L. specially to K. Emmerson, M. Oramas and E. C. Hernández for donating some of the material and data. A. Martín and J. C. Rando identified some prey items, and the ICONA's personal from La Gomera Island gave logistic support. All the studies carried out on the diet of feral cats on the Canaries were done without any government economie support. Bernie Zonfrillo revised the manuscript and made helpful comments.

El gato doméstico (Felis catus) ha sido introducido por el hombre en muchas regiones del mundo (Serpell 1988), tanto en ecosistemas continentales como en insulares, habiéndose asilvestrado posteriormente en muchos de ellos. Los gatos cimarrones se comportan como unos depredadores generalistas, siendo sus presas más comunes aquellas especies más abundantes y fáciles de capturar (Marshall 1961, Coman y Brunner 1972, Pascal 1980, Van Aarde 1980, Veitch 1985). Diversos estudios han demostrado que el gato cimarrón se alimenta de una gran variedad de presas (Jones 1977); su dieta puede estar constituida mayoritariamente por aves (Derenne 1976), o bien por mamíferos introducidos como el conejo (Oryctolagus cuniculus) (Jones 1977) y diversod múridos (Condé et al. 1972, Karl y Best 1982).

Invasive plant species are increasingly altering species composition and the functioning of ecosystems from a local to a global scale. The grass species Pennisetum setaceum has recently raised concerns as an invader on different archipelagos worldwide. Among these affected archipelagos are the Canary Islands, which are a hotspot of endemism. Consequently, conservation managers and stakeholders are interested in the potential spreading of this species in the archipelago. We identify the current extent of the suitable habitat for P. setaceum on the island of La Palma to assess how it affects island ecosystems, protected areas (PAs), and endemic plant species richness. We recorded in situ occurrences of P. setaceum from 2010 to 2018 and compiled additional ones from databases at a 500 m × 500 m resolution. To assess the current suitable habitat and possible distribution patterns of P. setaceum on the island, we built an ensemble model. We projected habitat suitability for island ecosystems and PAs and identified risks for total as well as endemic plant species richness. The suitable habitat for P. setaceum is calculated to cover 34.7% of the surface of La Palma. In open ecosystems at low to mid elevations, where native ecosystems are already under pressure by land use and human activities, the spread of the invader will likely lead to additional threats to endemic plant species. Forest ecosystems (e.g., broadleaved evergreen and coniferous forests) are not likely to be affected by the spread of P. setaceum because of its heliophilous nature. Our projection of suitable habitat of P. setaceum within ecosystems and PAs on La Palma supports conservationists and policymakers in prioritizing management and control measures and acts as an example for the potential threat of this graminoid invader on other islands.