Extinction behind our backs: the possible fate of one of the Darwin s finch species on Isla Floreana, Galápagos
نویسندگان
چکیده
Without regular monitoring a rare species may slip into extinction unnoticed. We report a possible case from the Galápagos archipelago. The warbler finch (Certhidea fusca) has not been recorded by scientists on Isla Floreana in recent years, and we have been concerned about its status. On a two-day visit to prime habitat in the breeding season of 2004 we used playback of warbler finch song and calls recorded on another island to stimulate an approach of local birds. We failed to find a single warbler finch, whereas we encountered numerous small tree finches (Camarhynchus parvulus), medium tree finches (C. pauper) and yellow warblers (Dendroica petechia). Searches in 1979, 1983, 1997 and 1999 were also unsuccessful. Our continuing failure to find any warbler finches indicates the species must be extremely rare on the island, if not actually extinct. We discuss possible reasons for their demise and draw attention to other species that could be heading in the same direction. 2004 Elsevier Ltd. All rights reserved.
منابع مشابه
Holocene Vertebrate Fossils from Isla Floreana, Galapagos
Steadman, David W. Holocene Vertebrate Fossils from Isla Floreana, Galapagos. Smithsonian Contributions to Zoology, number 413, 103 pages, 25 figures, 4 plates, 12 tables, 1986.—This study surveys the late Holocene vertebrate fossil record from Isla Floreana, Galapagos. Over 20,000 fossils from four lava tubes in the arid lowlands near Post Office Bay are associated with six radiocarbon dates o...
متن کاملSaving Darwin's muse: evolutionary genetics for the recovery of the Floreana mockingbird.
The distribution of mockingbird species among the Galápagos Islands prompted Charles Darwin to question, for the first time in writing, the 'stability of species'. Some 50 years after Darwin's visit, however, the endemic Floreana mockingbird (Mimus trifasciatus) had become extinct on Floreana Island and, today, only two small populations survive on two satellite islets. As Darwin noted, rarity ...
متن کاملAvian population survey in the Floreana highlands: is Darwin’s Medium Tree Finch declining in remnant patches of Scalesia forest?
Island species typically exist in pathogen and predator sparse environments before human settlement, and are particularly vulnerable to the impacts of invasive species. In this study, we used the variable circular-plot method to estimate the density of birds in the highlands of Floreana Island, Galápagos Archipelago, where introduced parasites, predators, and habitat degradation are a known thr...
متن کاملDivergent foraging behavior in a hybrid zone: Darwin’s tree finches (Camarhynchus spp.) on Floreana Island
Hybrid speciation is increasingly recognized as a mechanism for novel evolutionary trajectories. However, we know very little about the ecology of a contact zone that has arisen in sympatry. This study examines the foraging behavior and fitness of two species of Darwin’s tree finches (Camarhynchus parvulus, C. pauper) and hybrid offspring on Floreana Island. Previous study showed that the perce...
متن کاملSpecies collapse via hybridization in Darwin's tree finches.
Species hybridization can lead to fitness costs, species collapse, and novel evolutionary trajectories in changing environments. Hybridization is predicted to be more common when environmental conditions change rapidly. Here, we test patterns of hybridization in three sympatric tree finch species (small tree finch Camarhynchus parvulus, medium tree finch Camarhynchus pauper, and large tree finc...
متن کامل