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1.
PLoS One ; 16(9): e0256270, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34492030

RESUMO

Climate change represents an unprecedented threat to global biodiversity and, for many species, gaps in our knowledge of their biology remain acute. Gaps in baseline knowledge, such as confirmed identifications (Linnean shortfalls) and adequate collections (Wallacean shortfalls), need to be minimized with new studies, since this is often critical for effective conservation. Despite the increase in scientific research on primates in the southwest of the Brazilian Amazon, little is known about the species Mico nigriceps (Ferrari & Lopes, 1992) Primates, Platirryni. In the current study, we sought to reduce the extent of the Wallacean shortfall for M. nigriceps, understand whether climate change represents a threat to the distribution of the species, and identify priority areas for its conservation. Accordingly, we provide 121 new records in 14 locations, obtained directly from the field, and five from the literature. Using this, we carried out ecological niche modeling, to better understand how environmental suitability might limit the area occupied by the species. We then projected a distribution for 2070 with the SSP2-4.5 (more optimistic) and SSP5-8.5 (more pessimistic) scenarios. Our data confirmed the geographic distribution of the species as being restricted to headwaters of the Ji-Paraná/Machado river, but with a 400 km extension to the south. Under the modeled climate change scenarios, the area suitable for the species declines by 21% under the most optimistic, and by 27% in the pessimistic, scenario across the projected 50-year period. Although we have expanded the area of known occurrence for this species, we point out that climate change threatens the stability of this newly-discovered population strongly, and that this danger is intensified by deforestation, fire and hunting. We recommend that further studies be carried out to confirm the presence of the species in adjacent areas, those indicated by generated models as being potential environmentally suitable. In addition, we recommend intensifying forest restoration in currently pastured areas, and protection of the areas forming the current and future habitat of this species through such measures as protected area creation.


Assuntos
Distribuição Animal/fisiologia , Biodiversidade , Callitrichinae/fisiologia , Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/métodos , Ecossistema , Animais , Brasil , Florestas , Modelos Teóricos
2.
Primates ; 62(2): 407-415, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33428014

RESUMO

Habituation is used in most field research with primates to minimize observer effects on their behavior. Despite its importance, there is little published on the methods used to habituate different taxa of primates or how these methods vary in different habitat types. We assessed changes in behavior and space use of two groups of Leontocebus lagonotus in the Ecuadorian Amazon in order to document this process. Although the subjects had not been studied before, visitors and researchers were more frequently in the home range of Group 1 than of Group 2. We followed both groups for 2 months, collecting behavioral data through scan sampling and recording the use of space (ground, understory, subcanopy, and canopy) and the routes along which we followed the groups. We then divided our data into two equivalent stages, randomized the data for each stage and looked for significant differences using Wilcoxon tests. Our results show a significant decrease in submissive behaviors toward the observer for both groups and a significant increase in resting and foraging for Group 1. In addition, Group 2 used the subcanopy significantly less and the understory more during the second stage. The routes the animals used were significantly longer in the second stage for Group 1, but not for Group 2. We conclude that our methodology is adequate to advance in the habituation of L. lagonotus in less than 2 months and that a group will habituate more quickly if it has had some previous neutral exposure to humans.


Assuntos
Técnicas de Observação do Comportamento/métodos , Comportamento Animal , Callitrichinae/fisiologia , Animais , Equador , Habituação Psicofisiológica , Humanos
3.
Am J Primatol ; 81(4): e22967, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30924189

RESUMO

Although potentially beneficial in terms of raising awareness and conservation funding, tourist visitation of wild primates can have negative impacts on visited groups. Tourism-generated noise is a relatively understudied facet of ecotourism research, and the effects of tourist-generated speech on free-ranging, wild primates has never been explored previously. This study investigates the behavioral responses of 10 groups of pygmy marmosets (Cebuella pygmaea) to human speech. Through the use of an experimental playback study using recorded human speech, we show that pygmy marmosets within the Tamshiyacu-Tahuayo Reserve, Peru, are significantly less visible, and often move completely out of sight after louder playbacks. Although no consistent differences were found in other behaviors with playback duration and volume, playbacks of human speech tended to increase the amount of time individuals were alert and decrease feeding and resting behaviors. Our results demonstrate that human speech can alter the behavior of visited primates, and identifies a decrease in primate visibility within the increasing volume. As all trials in this study took place near a marmoset group's feeding tree, moving out of sight from the visible study area is a particularly energetically costly behavior, and also has a negative effect on visitor enjoyment as it limits the time that they are able to view the target species. This response was not observed (nor was any other consistent behavior change) in control trials where the marmosets were exposed to human presence but not to speech, suggesting that negative tourist impacts can be reduced by encouraging tourists to refrain from speaking in the presence of visited primate groups.


Assuntos
Comportamento Animal , Callitrichinae/fisiologia , Ruído/efeitos adversos , Fala , Animais , Comportamento Alimentar , Humanos , Peru , Descanso
4.
Primates ; 59(4): 347-353, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29728783

RESUMO

Among the 13 Mico species recognized by the IUCN Red List of Threatened Species, six are listed as "Data Deficient". The geographic range of most of the Mico species has been estimated from only a few records. We report new localities and the geographic extension of Mico chrysoleucos. In addition, we confirmed the presence of the species in two distinct protected areas. We modeled the habitat suitability of M. chrysoleucos using the maximum entropy method and including new records obtained by the authors in the state of Amazonas, Brazil. From the total area of occurrence calculated for the species, 22.8% is covered by protected areas and indigenous lands. The annual mean deforestation rate estimated between 2000 and 2015 was 2.95%, and the total area deforested by 2015 was 3354 km2 or 8.6% of the total distribution limits of the species. The habitat lost between 2000 and 2015 was 3.2% (1131 km2) of the total potential distribution, while the habitat loss area legally protected was 31 km2, and the habitat loss in settlements was equal to 691 km2. Our results extend the geographic distribution of the species about 100 km farther south, with the Maracanã River being a possible geographic barrier for the species. The significantly low rate of habitat loss inside protected areas and indigenous land, when compared to unprotected areas, points out the importance of these areas to M. chrysoleucos conservation. The species is relatively wide-ranging, legally protected, and resilient to regional anthropic threats. However, the hydroelectric schemes and the improvement of the road system in southern Amazonia pose an imminent threat to the species.


Assuntos
Distribuição Animal , Callitrichinae/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Animais , Brasil
5.
Primates ; 56(2): 131-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25688005

RESUMO

Cruz Lima's saddle-back tamarin Saguinus fuscicollis cruzlimai Hershkovitz, 1966, was described from a painting by Eládio da Cruz Lima in his book Mammals of Amazonia, Vol. 1, Primates (1945). The painting was of four saddle-back tamarins from the upper Rio Purus, one of them distinct and the inspiration for Hershkovitz to describe it as a new subspecies. Its exact provenance was unknown, however, and the specimen was lost. Surveys in the Purus National Forest in 2011 resulted in sightings of this tamarin along the north bank of the Rio Inauini, a left-bank tributary of the middle Purus, and also on the left bank of the Purus, north and south of the Rio Inauini. It is possible that it extends north as far as the Rio Pauini, and that S. f. primitivus Hershkovitz, 1977, occurs north of the Pauini as far the Rio Tapauá, both also left-bank tributaries of the Purus. Morphometric and molecular genetic analyses and the coloration of the pelage indicate that this tamarin differs from its neighbors sufficiently to be considered a full species. In his doctoral dissertation [2010, Taxonomy, Phylogeny and Distribution of Tamarins (Genus Saguinus Hoffmannsegg, 1807) Georg-August Universität, Göttingen], C. Matauschek found that saddle-back and black-mantle tamarins diverged from the tamarin lineage around 9.2 million years ago; time enough to warrant their classification in a distinct genus. Leontocebus Wagner, 1840, is the first name available. In this article we re-describe Cruz Lima's saddle-back tamarin. We propose a neotype with a precise locality, and make it a full species in the genus Leontocebus.


Assuntos
Callitrichinae/anatomia & histologia , Callitrichinae/classificação , Distribuição Animal , Animais , Brasil , Callitrichinae/genética , Callitrichinae/fisiologia , Citocromos b/genética , Feminino , Masculino , Proteínas Mitocondriais/genética , Dados de Sequência Molecular , Saguinus/anatomia & histologia , Saguinus/classificação , Saguinus/genética , Saguinus/fisiologia , Análise de Sequência de DNA
6.
Primates ; 54(4): 331-4, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23975162

RESUMO

We present two new records for the vulnerable dwarf marmoset, Callibella humilis. The first record, based on observed and photographed individuals, is from a campinarana area on the left (west) bank of the Rio Madeirinha, a left (west)-bank tributary of the Rio Roosevelt in the state of Amazonas, municipality of Novo Aripuanã and extends the distribution of the species ~270 km southwards, to the left (west) bank of the rio Roosevelt. The second record is based on an individual collected from the mouth of the Rio Roosevelt, at less than 10 km from the type locality of Mico marcai. This indicates that the species occurs sympatrically with M. marcai and probably Mico melanurus. We also present the first sonogram analysis of its long call structure, which shows some similarities, in the note duration and frequency, with Cebuella pygmaea and Mico argentatus.


Assuntos
Distribuição Animal , Callitrichinae/fisiologia , Vocalização Animal , Animais , Brasil , Masculino , Espectrografia do Som
7.
Int. j. morphol ; 24(2): 215-220, jun. 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-432804

RESUMO

RESUMEN: El Tití León Dorado, (Leontopithecus rosalia) es un primate (especie de los Tamarinos y Titíes) de la foresta atlántica brasileña en serio riesgo de extinción. Poco se conoce acerca de su anatomía, específicamente de las uniones musculares. Debido a ello, con el objetivo de comprender la locomoción de éste y otros primates, estudiamos la morfología y morfometría de los músculos grácil y sartorio y la relación entre ellos, en 3 especies de Leontopithecus rosalia. Se examinaron 18 animales adultos, de ambos sexos, sin anormalidades físicas en la región estudiada. El material pertenece a la colección del Centro de Primatología de Rio de Janeiro, Brasil. Los miembros posteriores fueron disecados hasta el nivel de los músculos grácil y sartorio, donde se efectuó la morfometría, obteniéndose, entre los músculos mencionados un área para su análisis histológico. Describimos la morfología de los músculos grácil y sartorio. Se obtuvieron valores promedio de la morfometría muscular y se estudió histológicamente la unión entre esos músculos. El análisis morfológico y morfométrico permite sugerir parámetros descriptivos de esos músculos. El análisis histológico permite concluir que las fibras del músculo grácil y del músculo sartorio no están fusionadas sino que se mantienen juntas a través de tejido conjuntivo, así, se insertan en el lado medial de la tibia. Funcionalmente, creemos que los músculos grácil y sartorio contribuyen a una activa contención de la articulación de la rodilla y sobre la biomecánica de los miembros posteriores de esos primates, conocidos como corredores.


Assuntos
Masculino , Adulto , Animais , Feminino , Callitrichinae/anatomia & histologia , Callitrichinae/crescimento & desenvolvimento , Callitrichinae/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/fisiologia , Músculo Esquelético/irrigação sanguínea , Desenvolvimento Muscular/fisiologia , Osso Púbico/anatomia & histologia , Osso Púbico/inervação , Osso Púbico/irrigação sanguínea
8.
Am J Primatol ; 66(2): 145-58, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15940711

RESUMO

Local variations in fruit- and leaf-eating have been reported for some primate species; however, similar variations in exudate-feeding of pygmy marmosets, one of the most specialized neotropical primate species, have not been studied. In our 3-year study of four populations of pygmy marmosets in northeastern Ecuador, we characterized their exudate-feeding behavior by describing the use of exudate sources. We tested whether the use of exudate species was related to ecological factors such as the availability of exudate species in an area. We estimated the daily activity budgets of the groups with 1-hr scan samples and found significant interpopulation differences in the time spent on exudate feeding. We recorded a total of 18 exudate species used in the four populations; however, the populations differed in the total number of species used and in the preferred species. The most commonly used plant species were Sterculia apetala at San Pablo, Cedrela odorata at Sacha, Inga marginata at Amazoonico, and Parkia balslevii at Zancudo. We recorded the presence and abundance of the 18 exudate species in 90-m transects in the home range of each group and in one additional control area that contained no marmosets, for each population. Differences in the most-used exudate species among populations did not appear to be related to the availability of these species in each population, i.e., the marmosets did not use at random the exudate species available within their range, nor did they use more often the exudate species that were more abundant in their home ranges. One implication of our results for conservation is that protecting exudate resources based on data from only one area will not be sufficient to preserve pygmy marmosets in all populations.


Assuntos
Callitrichinae/fisiologia , Dieta , Comportamento Alimentar/fisiologia , Animais , Equador , Observação , Plantas/metabolismo , Fatores de Tempo
9.
Can Vet J ; 45(6): 481-5, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15283517

RESUMO

The cardiovascular, respiratory, and anesthetic effects of medetomidine-ketamine (20 microg/kg bodyweight [BW] and 10 mg/kg BW) (MK group) or dexmedetomidine-ketamine (10 microg/kg BW and 10 mg/kg BW) (DK group) were studied in golden-headed lion tamarins. Heart rate decreased after administration of both combinations; this reduction was statistically greater in the DK group than in the MK group after 15 and 45 minutes. Systolic arterial pressure decreased in a similar way in both groups, except at 15 minutes, when systolic arterial pressure was significantly lower in the DK group. Diastolic arterial pressure, mean arterial pressure, respiratory rate, and rectal temperature were progressively reduced in all groups. Sedation time was significantly shorter and anesthesia time was significantly longer in the DK group compared with MK group. Anesthetic quality and analgesia scores were significantly greater at 5 and 15 minutes in the DK group compared with the MK group. The administration of dexmedetomidine-ketamine is as safe and effective as the administration of medetomidine-ketamine in tamarins.


Assuntos
Anestésicos Combinados , Anestésicos Dissociativos , Callitrichinae/fisiologia , Dexmedetomidina , Hipnóticos e Sedativos , Ketamina , Medetomidina , Analgesia/veterinária , Anestésicos Combinados/farmacologia , Anestésicos Dissociativos/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Dexmedetomidina/farmacologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hipnóticos e Sedativos/farmacologia , Ketamina/farmacologia , Masculino , Medetomidina/farmacologia , Distribuição Aleatória , Respiração/efeitos dos fármacos , Segurança , Fatores de Tempo
10.
Am J Primatol ; 63(1): 1-15, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15152369

RESUMO

Lion tamarins (Callitrichidae: Leontopithecus) are small frugi-faunivores that defend large home ranges. We describe results from the first long-term investigation of wild golden-headed lion tamarins (L. chrysomelas; GHLTs). We present data about activity budgets, daily activity cycles, diet, daily path length, home range size, home range overlap, and territorial encounters for three groups of GHLTs that were studied for 1.5-2.5 years in Una Biological Reserve, Bahia State, Brazil, an area characterized by aseasonal rainfall. We compare our results to those from other studies of lion tamarins to identify factors that may influence foraging and ranging patterns in this genus. Ripe fruit, nectar, insects, and small vertebrates were the primary components of the GHLT diet, and gums were rarely eaten. Fruit comprised the majority of plant feeding bouts, and the GHLTs ate at least 79 different species of plants from 32 families. The most common foraging sites for animal prey were epiphytic bromeliads. The GHLTs defended large home ranges averaging 123 ha, but showed strong affinities for core areas, spending 50% of their time in approximately 11% of their home range. Encounters with neighboring groups averaged two encounters every 9 days, and they were always aggressive. Data about time budgets and daily activity cycles reveal that the GHLTs spent most of their time foraging for resources or traveling between foraging sites distributed throughout their home ranges. The GHLTs spent much less time consuming exudates compared to lion tamarins in more seasonal environments. Additionally, the GHLTs had much larger home ranges than golden lion tamarins (L. rosalia), and did not engage in territorial encounters as frequently as L. rosalia. GHLT ranging patterns appear to be strongly influenced by resource acquisition and, to a lesser extent, by resource defense.


Assuntos
Callitrichinae/fisiologia , Dieta , Comportamento Alimentar/fisiologia , Comportamento Espacial/fisiologia , Fatores Etários , Agressão/fisiologia , Animais , Brasil , Demografia , Feminino , Estudos Longitudinais , Masculino , Atividade Motora/fisiologia
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