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1.
PLoS One ; 17(10): e0276297, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36264921

RESUMO

Many vertebrate species undergo population fluctuations that may be random or regularly cyclic in nature. Vertebrate population cycles in northern latitudes are driven by both endogenous and exogenous factors. Suggested causes of mysterious disappearances documented for populations of the Neotropical, herd-forming, white-lipped peccary (Tayassu pecari, henceforth "WLP") include large-scale movements, overhunting, extreme floods, or disease outbreaks. By analyzing 43 disappearance events across the Neotropics and 88 years of commercial and subsistence harvest data for the Amazon, we show that WLP disappearances are widespread and occur regularly and at large spatiotemporal scales throughout the species' range. We present evidence that the disappearances represent 7-12-year troughs in 20-30-year WLP population cycles occurring synchronously at regional and perhaps continent-wide spatial scales as large as 10,000-5 million km2. This may represent the first documented case of natural population cyclicity in a Neotropical mammal. Because WLP populations often increase dramatically prior to a disappearance, we posit that their population cycles result from over-compensatory, density-dependent mortality. Our data also suggest that the increase phase of a WLP cycle is partly dependent on recolonization from proximal, unfragmented and undisturbed forests. This highlights the importance of very large, continuous natural areas that enable source-sink population dynamics and ensure re-colonization and local population persistence in time and space.


Assuntos
Artiodáctilos , Animais , Florestas , Mamíferos
2.
J Wildl Dis ; 54(4): 700-707, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29902129

RESUMO

In South America, wild populations of peccaries coexist with domestic and feral pigs, with poorly understood consequences. We captured 58 collared peccaries ( Pecari tajacu) and 15 feral pigs ( Sus scrofa) in locations of Colombia where coexistence of these species is known. Blood samples were tested for antibodies against four viral agents, classical swine fever virus (CSFV), Aujeszky's disease virus (ADV), porcine circovirus (PCV-2), and vesicular stomatitis virus (New Jersey and Indiana subtypes) and two bacterial agents, Brucella spp. and six serovars of Leptospira interrogans. The prevalence of CSFV was 5% (3/58) in collared peccaries and 7% (1/15) in feral pigs. The prevalence of PCV-2 was 7% (1/15) in collared peccaries and 67% (2/3) in feral pigs. Vesicular stomatitis prevalence was 33% (8/24) in collared peccaries and 67% (4/6) in feral pigs. Leptospira prevalence was 78% (39/50) in collared peccary and 100% (8/8) in feral pigs; bratislava, grippotyphosa, icterohaemorrhagiae, and pomona were the most frequent serovars. Also, the only white-lipped peccary ( Tayassu pecari) sampled was positive for L. interrogans serovar bratislava and for vesicular stomatitis virus, New Jersey strain. No samples were positive for ADV or Brucella. The seroprevalence of antibodies against L. interrogans was similar to that observed in other studies. Icterohaemorrhagiae appears to be a common serovar among in situ and ex situ peccary populations. Positive antibodies against PVC-2 represent a novel report of exposure to this pathogen in Colombian peccaries. Our results indicate the possible transmission of various pathogens, important for pig farms, in the studied pig and peccaries.


Assuntos
Infecções Bacterianas/veterinária , Doenças dos Suínos/sangue , Viroses/veterinária , Animais , Animais Selvagens , Artiodáctilos , Infecções Bacterianas/sangue , Infecções Bacterianas/epidemiologia , Colômbia/epidemiologia , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Viroses/sangue , Viroses/epidemiologia
3.
Acta biol. colomb ; 25(3): 322-332, sep.-dic. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1149012

RESUMO

RESUMEN La Serranía de La Lindosa es una formación geomorfológica que presenta heterogeneidad en sus coberturas vegetales. Esta zona se encuentra en una situación contradictoria debido a que presenta una elevada biodiversidad, sin embargo, es uno de los actuales focos de deforestación más grandes de Colombia. A pesar de que se espera una alta diversidad de murciélagos en La Lindosa existe poca información publicada sobre este grupo. Este trabajo presenta los resultados de inventarios de murciélagos realizados durante cinco años en la Serranía de la Lindosa. Se compara la diversidad (riqueza, composición y estructura) de los ensamblajes de murciélagos en dos tipos principales de cobertura vegetal, los bosques húmedos y las sabanas casmófitas. Los inventarios recogen información de 735 murciélagos capturados, correspondientes a 46 especies. De estas, 14 especies se encontraron solamente en sabanas casmófitas, 11 en bosques húmedos y 19 en los dos tipos de vegetación. De esta manera, se evidencia una alta complementariedad en la composición de especies de murciélagos entre los dos tipos de vegetación. Adicionalmente, la estructura de los ensamblajes de murciélagos varió entre los dos ambientes. La abundancia entre las especies es más homogénea en las sabanas casmófitas con un mayor número de especies raras comparado con los bosques húmedos. En general, la alta diversidad de murciélagos de la Serranía de La Lindosa puede estar relacionada con la heterogeneidad en la vegetación, la presencia de diferentes tipos de cuevas, y la historia evolutiva de las especies de murciélagos asociados a la Región Guayana.


ABSTRACT The Serranía La Lindosa is a geomorphological formation with land cover heterogeneity. This area faces a contradictory situation because it has high biodiversity and provides several ecosystem services, and yet it is one of the current largest deforestation sites in Colombia. Bats is a taxonomic group with high expected diversity in La Lindosa, but there is little published information about this group. This paper presents the results of bat inventories carried out during five years in the Lindosa mountain range. Additionally, diversity is compared in terms of species richness, composition, and structure of bat assemblies in two main types ofvegetation cover evident in the area, which are humid forests and casmophytic savannas. Inventories collected information on 735 captured bats, corresponding to 46 species. Of these, 14 species were found only in casmophytic savannas, 11 in humid forests, and 19 in both types of vegetation. Thus, there is high complementarity in bat species composition between the two vegetation types. Additionally, the structure of bat assemblies varied between the two environments, with a proportional distribution of species abundance more homogeneous in casmophytic savannas than in forests. Besides, a higher number of rare species was found in casmophytic savannas. In general, the high diversity of bats of the Serranía de La Lindosa could be associated with vegetation heterogeneity, presence of different cave types and evolutionary history of bat species associated with the Guayana Region.

4.
Rev. med. vet. (Bogota) ; (40): 69-83, ene.-jun. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1139286

RESUMO

Resumen Algunas investigaciones de mamíferos silvestres requieren del uso de métodos que faciliten la manipulación de los individuos en condiciones de campo, sin afectar negativamente a los animales o a los investigadores. Dentro de estos métodos, se encuentra la inmovilización química, la cual no ha sido muy documentada en roedores silvestres de la subfamilia Sigmodontinae (Cricetidae). Por ello, en esta investigación se evaluó el uso de éter dietílico inhalado para manipular roedores sigmodontinos en campo, comparando el tiempo de inducción y el tiempo de recuperación de la anestesia entre especies, sexos y tipos de ambientes. Se capturaron y anestesiaron un total de 289 individuos de seis especies en el Parque Nacional Natural Chingaza. El tiempo de inducción de la anestesia fue diferente entre Microryzomys minutus, Neomicroxus bogotensis, Thomasomys laniger y Thomasomys niveipes (F3; 552 = 9,36; p < 0,05); de igual forma, el tiempo de recuperación de la anestesia fue diferente entre dichas especies (H = 9,59; p = 0,022). No se encontraron diferencias en los tiempos de inducción y recuperación de la anestesia entre sexos, ni entre ambientes. La mortalidad total fue de 4,5 %. No se observaron secreciones mucosas, vómito o complicaciones cardíacas o respiratorias en los individuos anestesiados. Los individuos fueron recapturados y no se evidenciaron alteraciones en su comportamiento o aspecto físico que indicaran una afectación por la anestesia o manipulación en capturas previas. La anestesia inhalada con éter dietílico puede ser una opción rápida y segura para inmovilizar y manipular sigmodontinos durante procedimientos cortos en campo dentro de estudios poblacionales o programas de monitoreo en vida silvestre.


Abstract Some researches in wild mammals require methods that enable to handle the animals living in wild conditions, without affecting negatively the animals, or the researchers. These methods include the chemical immobilization, which has not been enough documented when handling wild rodents of the Sigmodontinae subfamily (Cricetidae). Therefore, this research evaluated the use of diethyl ether when handling Sigmodontinae rodents out in the countryside. It compared the induction time to the anesthesia recovery time between species, genders, and type of environments. A total of 289 animals were caught and anesthetized from six species in the Chingaza National Natural Park. The anesthesia induction times were different between Microryzomys minutus, Neomicroxus bogotensis, Thomasomys laniger y Thomasomys niveipes (F3; 552 = 9.36; p < 0.05). Likewise, the anesthesia recovery times were different between the same species (H = 9.59; p = 0.022). No difference was found in the induction times and the anesthesia recovery times between genders, neither for the types of environment. Total mortality was 4.5%. None mucosal secretions, vomit, or cardiac/respiratory complications were observed in the anesthetized animals. These subjects were caught again and they did not show any alterations in their behavior or physical aspect indicating affection derived either from the anesthesia or the previous handling under captivation. Anesthesia with diethyl ether can be a quick and safe choice when it comes to immobilize and handle Sigmodontinae rodents during short procedures out in the countryside, when carrying out population studies or wildlife monitoring programs.

5.
Acta biol. colomb ; 14(supl.1): 255-268, Dec. 2009.
Artigo em Espanhol | LILACS | ID: lil-634967

RESUMO

Este artículo revisa tres de las principales causas de amenaza a la diversidad biológica, como son la fragmentación y pérdida del hábitat, así como la invasión de especies exóticas, principalmente en lo que compete a sus implicaciones evolutivas. Los efectos de la fragmentación y/o pérdida del hábitat pueden revisarse a la luz de la sinergia entre factores demográficos y genéticos que moldean cambios evolutivos o que llevan a las poblaciones al vórtice de la extinción. Las invasiones biológicas, aunque han generado pérdidas considerables en la diversidad biológica, ofrecen un escenario interesante para estudiar procesos evolutivos contemporáneos.


This paper reviews three of the main threats to biological diversity, such as habitat fragmentation /habitat loss, and invasion of exotic species, mainly from their evolutionary implications. Effects of habitat fragmentation/habitat loss could be addressed by looking at the synergy between demographic and genetic factors that together shape evolutionary changes or otherwise bring populations to extinction vortex. Biological invasions, in spite of their strong negative effects on biological diversity, offer an interesting scenario to study contemporary evolutionary processes.

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