Spool-and-line studies on the behavioural ecology of rats (Rattus spp.) in the Galápagos Islands

1996 ◽  
Vol 74 (4) ◽  
pp. 733-737 ◽  
Author(s):  
Gillian E. Key ◽  
Richard D. Woods
Keyword(s):  
Habitat Use ◽  
Vegetation Structure ◽  
Rattus Rattus ◽  
Behavioural Ecology ◽  
Radio Tracking ◽  
Galápagos Islands ◽  
Santa Cruz Island ◽  
Santa Cruz ◽  
Total Length ◽  
Significant Difference

The spool-and-line technique has been neglected in the study of the behavioural ecology of mammals. It has advantages over the more widely used method of radio tracking in terms of cost and depth of detail in the data obtained, despite its limitations. A spool and line was used to study habitat use of two species of Rattus on Santa Cruz Island, Galápagos, in areas of sympatry and allopatry. Significantly longer total spool lines were collected from R. rattus than R. norvegicus, and R. rattus also climbed trees significantly more. Significantly longer spool lines were collected from female than male R. rattus, and rats caught in the morning spent significantly more time on the ground than those caught at night. The method of handling and the occasion of capture (first, second, or third) had no significant effect on either the total length of spool line collected or the proportion of time spent on the ground. Arboreality in R. rattus was compared with that in R. norvegicus between areas of sympatry and allopatry, and a significant difference was found between sites in terms of both the total length of spool line collected and the proportion of time spent on the ground. Rattus rattus was least arboreal at site D, an area of allopatry, and most arboreal at site B, where the fewest trees occurred, suggesting that factors other than vegetation structure influence arboreality. The use of spool-and-line devices in the study of behavioural ecology is discussed.

scholarly journals Human-caused and natural mortality of giant tortoises in the Galapagos Islands during 1995-2004

Oryx ◽  
2007 ◽  
Vol 41 (3) ◽  
pp. 337-342 ◽  
Author(s):  
Cruz Márquez ◽  
David A. Wiedenfeld ◽  
Sandra Landázuri ◽  
Juan Chávez
Keyword(s):  
National Park ◽  
National Park Service ◽  
Charles Darwin ◽  
Galapagos Islands ◽  
Research Station ◽  
Natural Mortality ◽  
Galápagos Islands ◽  
Santa Cruz Island ◽  
Santa Cruz ◽  
Park Service

AbstractAlthough the killing of giant tortoises in the Galapagos Islands has been prohibited since 1933, poaching of tortoises still occurs. Personnel of the Galapagos National Park Service and the Charles Darwin Research Station regularly survey populations of tortoises throughout the archipelago and report all dead tortoises found. For the 10-year period 1995–2004 the field personnel reported evidence of 190 giant tortoises killed, primarily on the southern portion of Isabela Island. For the first 6 years the number of tortoises found killed was <15 per year, but since 2001 the number killed has increased dramatically, with 49 tortoises poached in 2004. During the same 10 years the number of tortoises found dead from natural causes was 131. Many of these deaths can be attributed to events associated with the 1997–1998 El Niño or with outbreaks of disease on Santa Cruz Island in 1996 and 1999. The results indicate that poaching exceeds natural mortality, and is a significant factor affecting these long-lived and slow-reproducing animals. Environmental education efforts in the human population of southern Isabela appear to have had little effect. Because tortoise poaching takes place at a small number of sites, effective enforcement at those sites could reduce killing of tortoises.

Baseline data for identifying potentially invasive plants in Puerto Ayora, Santa Cruz Island, Galápagos

2008 ◽  
Vol 14 (2) ◽  
pp. 93 ◽  
Author(s):  
A. M. Guerrero ◽  
P. Pozo ◽  
S. Chamorro ◽  
A. Guezou ◽  
C. E. Buddenhagen
Keyword(s):  
Introduced Species ◽  
Plant Species ◽  
Invasive Plants ◽  
New Records ◽  
Galapagos Islands ◽  
Galápagos Islands ◽  
Santa Cruz Island ◽  
Santa Cruz ◽  
Number Of Species ◽  
And Behavior

We recorded 502 introduced plant species during an inventory of all 2 334 private properties in Puerto Ayora, the largest town on Santa Cruz Island and the Galapagos Islands (population > 10,000) which accounts for about half of the Galapagos population. A third of these species were new records for the Galapagos Islands, 73% were found only in cultivation, 18% were naturalized and not cultivated (in Puerto Ayora), and 9% were found in cultivation and naturalized (escaped). Seventeen species previously known to occur only in cultivation in Galapagos are now considered escaped. A number of species known to be naturalized in the humid highlands of Santa Cruz do not appear to be able to reproduce in Puerto Ayora?s drier climate. To determine which introduced species should be a priority for control or eradication, the potential invasiveness of each species was assessed based on their distribution and behavior in Galapagos and elsewhere. At least 13 species were considered potentially serious invaders that could be feasible to eradicate.

The pholcid spiders of the Galápagos Islands, Ecuador (Araneae: Pholcidae)

1992 ◽  
Vol 70 (6) ◽  
pp. 1185-1199 ◽  
Author(s):  
Willis J. Gertsch ◽  
Stewart B. Peck
Keyword(s):  
New Species ◽  
Galapagos Islands ◽  
Santa Fe ◽  
Galápagos Islands ◽  
Santa Cruz Island ◽  
Santa Cruz ◽  
New Synonym ◽  
Stridulatory Apparatus ◽  
Parapatric Speciation ◽  
First Time

The 12 known species of the family Pholcidae in the Galápagos Islands are diagnosed, illustrated, and assigned to six genera as follows: Coryssocnemis conica Banks (for which a lectotype is designated), known from many islands; Coryssocnemis insularis Banks (for which a lectotype is designated), known from five islands; Coryssocnemis jarmila new species, a troglobite from Santa Cruz Island; Coryssocnemis floreana new species, a troglobite from Floreana Island; Hedypsilus culicinus Simon (for which a lectotype is designated), from Santa Cruz and San Cristóbal islands; Hedypsilus modicus new species, from San Cristóbal and Santiago islands (Modisimops Mello-Leitão is a NEW SYNONYM of Hedypsilus); Modisimus solus new species, from Santa Cruz Island; Pholcophora bella new species, from Santa Cruz Island; Pholcophora baerti new species, from Santa Fe and Pinta; Anopsicus banksi (Gertsch) from Floreana Island; Metagonia bellavista new species, a troglobite from Santa Cruz Island; and Metagonia reederi new species, a troglobite from Isabela Island. All are endemic to the islands, except H. culicinus, which is probably introduced. A stridulatory apparatus is reported on females of the genus Coryssocnemis for the first time. The troglobitic species of Coryssocnemis may have originated by parapatric speciation processes; the troglobitic species of Metagonia are relicts. In the troglobites the female epigynal characters are more differentiated than male palpal characters. A minimum of eight ancestral colonizations founded the Galápagos pholcid fauna.

scholarly journals Emergent conservation conflicts in the Galapagos Islands: Human-giant tortoise interactions in the rural area of Santa Cruz Island

PLoS ONE ◽  
2018 ◽  
Vol 13 (9) ◽  
pp. e0202268 ◽  
Author(s):  
Francisco Benitez-Capistros ◽  
Giorgia Camperio ◽  
Jean Hugé ◽  
Farid Dahdouh-Guebas ◽  
Nico Koedam
Keyword(s):  
Rural Area ◽  
Galapagos Islands ◽  
Galápagos Islands ◽  
Santa Cruz Island ◽  
Santa Cruz

scholarly journals Rediscovery of rodents (Genus Nesoryzomys) considered extinct in the Galápagos Islands

Oryx ◽  
2000 ◽  
Vol 34 (2) ◽  
pp. 109-117 ◽  
Author(s):  
Robert C. Dowler ◽  
Darin S. Carroll ◽  
Cody W. Edwards
Keyword(s):  
Charles Darwin ◽  
Rattus Rattus ◽  
Galapagos Islands ◽  
Santa Fe ◽  
Galápagos Islands ◽  
Santa Cruz ◽  
Emergency Plans ◽  
Extant Species ◽  
History Of ◽  
Rodent Populations

AbstractThe history of the endemic rodents of the Galápagos Islands began with the discovery of the first Galápagos rice rat species by Charles Darwin in 1835 and the last species was described as recently as 1980. Unfortunately, of the seven described species known to occur in the islands during the past 150 years, only two were known to be extant to 1995. Since then, two expeditions to the Galápagos Islands have been conducted to survey endemic rodent populations. The first confirmed the existence of a small endemic rice rat, Nesoryzomys fernandinae, on Fernandina, known previously only from owl pellet remains found in 1979. In 1997, an expedition to Santiago revealed a population of the larger rice rat N. swarthi, a species collected alive only once in 1906 and considered extinct in all recent literature on the Galápagos Islands. Survey efforts on Santa Cruz resulted only in the collection of introduced rodent species (Rattus rattus, R. norvegicus and Mus musculus). The extant species of native rodents in the Galápagos Islands now number four: N. narboroughi and N. fernandinae on Fernandina; N. swarthi on Santiago; and Oryzomys bauri on Santa Fe. Three species are found on islands where no introduced rodents or cats occur, whereas only one (N. swarthi) co-exists with R. rattusand M. musculus. Nesoryzomys darwini and N. indefessus on Santa Cruz and O. galapagoensis on San Cristóbal are still considered extinct. Strategies for conservation should include monitoring islands for introduced rodents and cats, development of emergency plans in the event of introductions, and captive management.

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