Lontra Longicaudis Research Articles

Leptospira borgptersenii and Leptospira interrogans identified in wild mammals in Rio Grande do Sul, Brazil.

Leptospira spp. are bacteria responsible for leptospirosis, a zoonotic disease with considerable impacts on the economy, animal health, and public health. This disease has a global distribution and is particularly prevalent in Brazil. Both rural and urban environments are habitats for Leptospira spp., which are primarily transmitted through contact with the urine of infected animals. Consequently, domestic and wild species can harbor these prokaryotes and serve as infection sources for other hosts. In the context of wild animals, there is a dearth of molecular studies elucidating the roles of various animal and bacterial species in the epidemiology of leptospirosis. Therefore, this study aimed to evaluate the presence of Leptospira spp. DNA in different species of free-living and captive wild animals and to assess the phylogenetic relationships of the identified microorganisms in Rio Grande do Sul, Brazil. The samples were evaluated for the presence of the gene lipL32 by polymerase chain reaction (PCR) and sequencing of the amplified fragment after which phylogenetic analyzes were carried out. DNA from Leptospira spp. was extracted from kidney tissue from wild animals (Mammalia class). Pathogenic Leptospira spp. DNA was detected in 9.6% (11/114) of the samples, originating from nine species of wild animals, including the white-eared opossum (Didelphis albiventris), skunk (Conepatus chinga), geoffroy's cat (Leopardus geoffroyi), margay (Leopardus wiedii), pampas fox (Lycalopex gymnocercus), capybara (Hydrochoerus hydrochaeris), common marmoset (Callithrix jacchus), neotropical river otter (Lontra longicaudis), and european hare (Lepus europaeus). Phylogenetic analysis revealed the presence of Leptospira borgpetersenii and Leptospira interrogans in these animals. This research is the first study contributing to the epidemiology of leptospirosis by identifying L. borgpetersenii and L. interrogans in free-living and captive wild animals in Rio Grande do Sul, Brazil, potentially acting as bacterial reservoirs. Additionally, our findings can inform sanitary measures for controlling and preventing the disease, thereby safeguarding public health.

Predation of the swamp racer Palusophis bifossatus by the caiman Caiman yacare and by the otter Lontra longicaudis

Predation of the swamp racer Palusophis bifossatus by the caiman Caiman yacare and by the otter Lontra longicaudis

Could Lontra longicaudis be considered a flagship species of the southern Yucatan Peninsula? Perspectives on its distribution, ecology, and conservation

There are historical reports of the Neotropical otter (Lontra longicaudis) in water bodies of the Yucatan Peninsula, and some efforts have been made to understand villagers’ perceptions of this threatened species. However, these studies vary in terms of season and location, and the data are limited and outdated. To help fill these gaps, our objective was to determine the current local knowledge on the conservation status of this species in the southern Yucatan Peninsula, Mexico, and the northeastern part of Petén, Guatemala. In 2021 and 2022, we conducted 90 semi-structured interviews with users of local water bodies in Mexico, including Río Hondo (n = 52), Laguna Bacalar (n = 17), and Laguna Guerrero (n = 6), and two natural protected areas (n = 15) in Petén, Guatemala. We tested whether associations existed between the characteristics of the interviewees (e.g., schooling level and activity in the water body) and their responses. We obtained information on 122 otter sightings, most of which involved single individuals (80 %). We found associations among the schooling level (e.g., elementary, high school), the activities of the interviewees (e.g., fishing, tourism services, technical activities), the water bodies and the perceived threats and values given to the otter. Our study provides updated information on the local perception of the species in a transboundary region and suggests that this species does not pose a competitive threat to local human fishing interests. Therefore, this species could be considered a flagship species for promoting regional conservation awareness in unprotected areas.

Carnivore coexistence without competition: giant otters are more nocturnal around dens than sympatric neotropical otters.

Nocturnal activity of tropical otters is rarely reported. To date no studies have documented den use by sympatric giant (Pteronura brasiliensis) and neotropical otters (Lontra longicaudis). We used camera-traps to monitor den use by sympatric otters along an equatorial Amazonian river. Camera-traps provided evidence that giant otters were more nocturnal around dens than sympatric neotropical otters. Nocturnal activity was recorded in 11% of giant otter photos (n = 14 of 125 photos), but was recorded only once for neotropical otters. Den use by giant and neotropical otters overlapped spatially and temporally but not concurrently. We hypothesize that previously reported nocturnal activity in neotropical otters is facilitated by the absence or low density of giant otters. Our results also underscore the need to use complementary techniques together with den counts for monitoring otters as sympatric species can use the same dens.

Genome-wide data support recognition of an additional species of Neotropical river otter (Mammalia, Mustelidae, Lutrinae)

Abstract Cryptic biodiversity continues to be revealed worldwide, even in apparently well-known groups such as carnivorans. The Neotropical Otter (Lontra longicaudis) presents shape variation in its nose pad, a character that has been used to differentiate species in this group. Based on this, 3 subspecies are recognized: L. l. annectens (Mexico, Central America, and South America west of the Andes), L. l. enudris (Amazon and Orinoco basins), and L. l. longicaudis (Paraná basin and remaining distribution). Previous studies partially supported their distinctness based on mitochondrial DNA markers, morphometrics, and ecological niche modeling. We analyzed genome-wide nuclear markers (ultraconserved elements) of 29 L. longicaudis individuals across the species’ range to assess its population structure. Phylogenomic analysis recovered L. longicaudis as paraphyletic with robust support, with 1 clade comprising samples from Mexico and Colombia (trans-Andean populations) and another encompassing the remaining samples (cis-Andean populations), which grouped with 2 other South American species, L. felina and L. provocax. Principal component and admixture analyses strongly differentiated the 2 main L. longicaudis groups, and distinguished the Amazonian individuals from the remaining cis-Andean samples. Our results support the recognition of trans-Andean populations of L. longicaudis as a distinct otter species, which should be recognized as Lontra annectens.

Otterly diverse - A high diversity of Dracunculus species (Spirurida: Dracunculoidea) in North American river otters (Lontra canadensis)

The genus Dracunculus contains numerous species of subcutaneous parasites of mammals and reptiles. In North America, there are at least three mammal-infecting species of Dracunculus. Reports of Dracunculus infections have been reported from river otters (Lontra canadensis) since the early 1900s; however, little is known about the species infecting otters or their ecology. Most reports of Dracunculus do not have a definitive species identified because females, the most common sex found due to their larger size and location in the extremities of the host, lack distinguishing morphological characteristics, and few studies have used molecular methods to confirm identifications. Thus, outside of Ontario, Canada, where both D. insignis and D. lutrae have been confirmed in otters, the species of Dracunculus in river otters is unknown. In the current study, molecular characterization of nematodes from river otters revealed a high diversity of Dracunculus species. In addition to confirming D. insignis infections, two new clades were detected. One clade was a novel species in any host and the other was a clade previously detected in Virginia opossums (Didelphis virginiana) from the USA and a domestic dog from Spain. No infections with D. lutrae were detected and neither new lineage was genetically similar to D. jaguape, which was recently described from a neotropical otter (Lontra longicaudis) from Argentina. These data also indicate that Dracunculus spp. infections in otters are widespread throughout Eastern North America. Currently the life cycles for most of the Dracunculus spp. infecting otters are unknown. Studies on the diversity, life cycle, and natural history of Dracunculidae parasites in wildlife are important because the related parasite, D. medinensis (human Guinea worm) is the subject of an international eradication campaign and there are increasing reports of these parasites in new geographic locations and new hosts, including new species in humans and domestic dogs.

Lontra longicaudis as an environmental bioindicator

Lontra longicaudis as an environmental bioindicator

Anomalous origin of the right subclavian artery in a Neotropical otter (Lontra longicaudis, Olfers-1818).

The Neotropical otter (Lontra longicaudis) is a mustelid distributed geographically from Mexico to Argentina. Anomalous origins of the aortic arch branches are rarely reported in wild carnivorans. Therefore, this study aimed to report the anomalous branching of the aortic arch in one formaldehyde-fixed specimen of L. longicaudis. The aortic arch provided three branches: the bicarotid trunk and the left and right subclavian arteries. The latter passed dorsally to the esophagus toward the right side without a mark of compression at the esophagus. This is the first report of an anomalous origin of the right subclavian artery in L. longicaudis.

Novel Alpha‐, Beta‐, and Gammaherpesviruses in Neotropical Carnivores of Brazil

The knowledge regarding infectious agents affecting wildlife is crucial for species’ conservation. We hypothesized that herpesviruses are present in wild Neotropical carnivores. Herein, we used DNA polymerase and glycoprotein B broad‐spectrum PCRs to molecularly survey the presence of herpesviruses in spleen and/or lung samples of 53 wild Neotropical carnivores of Brazil, comprising the families Canidae, Felidae, Mustelidae, and Procyonidae. The percentage of PCR‐positives was 28.3% (15/53). An alphaherpesvirus was found in a Neotropical river otter (Lontra longicaudis, 1/1), a betaherpesvirus in a lesser grison (Galictis cuja, 1/3), and different gammaherpesviruses in Neotropical river otter (1/1), lesser grison (1/3), crab‐eating raccoons (Procyon cancrivorus, 8/9), South American coati (Nasua nasua, 1/2), southern tiger cat (Leopardus guttulus, 1/2), jaguarundi (Puma yagouaroundi, 1/5), and ocelot (Leopardus pardalis, 1/10). None of the tested canids were herpesvirus‐positive. This is the first report of herpesvirus in procyonids, and in jaguarundi, southern tiger cat, lesser grison, and Neotropical river otter. This study broadens the host range of herpesviruses in Neotropical carnivores.

Lontra longicaudis (Carnivora: Mustelidae: Lutrinae): a scientometric analysis.

A scientometric analysis of the Neotropical Otter is essential to establish the progress in studies with the species, in order to improve its conservation status. This study aimed to identify, categorize, and evaluate published scientific papers on Lontra longicaudis. Quantitative data was analyzed through absolute and relative frequencies, represented by tables and maps. The results showed that the publications on the Neotropical Otter increased since 1993 and have been primarily published in a specific journal (IUCN Otter Spec. Group Bull.) on the subfamily Lutrinae. Most authors reside in countries such as Brazil, Mexico, and Colombia, and publish predominantly in English. The majority of studies were conducted with free-living specimens, notably in the Brazilian state of Rio Grande do Sul and in Mexico. The most commonly used keywords match the most frequent subjects: "place of occurrence" and "diet". Despite the increase in publications, research on the Neotropical Otter is still largely limited to Brazil, Mexico, and sites near research institutions. Gaps on essential information for the species conservation, such as its biology, ecology, and behavior, were identified. The need for further studies on the Neotropical Otter in all the territory it inhabits is evident.

Primeiro relato de predação de um jacaré-coroa (Paleosuchus trigonatus) por uma lontra (Lontra longicaudis)

ABSTRACT Lontra longicaudis is a semi-aquatic predator which mainly feeds on fish and crustaceans, but which can opportunistically predate mammals, birds, and reptiles. In the Amazon, this species is sympatric with Paleosuchus trigonatus, one of the smallest species of crocodilians, whose possible means of defense is a very rigid skin, which causes adults to have few predators. Here we report the first documented case of predation of P. trigonatus by L. longicaudis.

Sonographic features of abdominal organs in healthy captive Neotropical otters (Lontra longicaudis).

This study aimed to assess the sonographic features of abdominal organs in healthy captive Neotropical otters (Lontra longicaudis). The sonograph showed that the urinary bladder was located in the caudal abdomen and its content was uniformly anechoic. The bladder wall had three layers: outer hyperechoic serosa, hypoechoic muscular layer and hyperechoic mucosa. The mean total wall thickness was 0.10 cm. The splenic parenchyma had a homogeneous echotexture with greater echogenicity than that of the left renal cortex and liver. The borders were regular and tapered. Rugal folds were observed in the stomach when undistended. The mean gastric wall thickness was 0.28 cm and five distinct layers were visible. The liver had smooth contours, and division of the hepatic lobes was not precisely visualized. The hepatic parenchyma had a homogeneous echotexture with greater echogenicity as compared to the right kidney and lesser echogenicity than that of the spleen. The gallbladder appeared as an oval or rounded structure in the transverse plane, filled with homogeneous anechogenic content; the wall was thin, regular and hyperechoic, with a mean thickness of 0.09 cm. The kidneys had a lobulated appearance with renicular subunits. The mean total length of the kidneys in longitudinal plane was 6.18 cm for the left and 6.27 cm for the right. Each reniculus was covered by an echogenic capsule, and the medullary region was more hypoechogenic than the cortical region. In conclusion, sonographic features in most of the abdominal organs in Neotropical otters are similar to the ultrasound patterns observed in healthy dogs and cats, except for kidneys with reniculi.

A new dracunculus species (Nematoda: Dracunculoidea) in neotropical otters (Lontra longicaudis) from Argentina: morphological and molecular characterization

A new species of Dracunculus is described in wild neotropical otters, Lontra longicaudis, occurring in Corrientes, Argentina, based on morphological and molecular characteristics. Worms were located in the subcutaneous tissue from two of five investigated otters. Dracunculus jaguape n. sp. is differentiated from the 14 species of Dracunculus described from mammals and reptiles by the prominent dorsal and ventral papillae on the head; deirids posterior to nerve ring; male with long needlelike spicules and presence of gubernaculum; and long first stage larva. Phylogenetic analysis using the 18S rRNA positioned Dracunculus jaguape n. sp. in an anterior position to the rest of Dracunculus sequences available and COI positioned it in a separated clade sister to Dracunculus lutrae sequences. This is the first report on the presence of this nematode in Lontra longicaudis in Argentina.

Evaluation of the human-otter conflict in central Veracruz, Mexico: recommendations for mitigation

ABSTRACT Evaluating human–wildlife conflict is necessary to reach positive long-term management solutions and aid the conservation of biodiversity. We used indirect approaches to evaluate the Human–Neotropical otter conflict in three river basins with high fishing activity in western Mexico and provided recommendations to mitigate the conflict by identifying the variables that increase the risk of predation of ponds by otters. Human–Otter conflict was moderate, and the opinions of community members toward otters were mostly negative, particularly those of the fishing sector. However, after offering environmental education workshops, the number of people recognizing the importance of protecting the species increased, which could result in the acceptance and tolerance toward otters. Avoiding building ponds at ground level and covering ponds with metal mesh, especially in fish-farms located in the middle and upper areas of rivers, as explored with fish-farmers, merits more experimentation, since it could be a good means for reducing the conflict.

Lontra longicaudis (Mustelidae) in La Vieja river basin, Risaralda, Colombia

The neotropical otter Lontra longicaudis is a conservation target in the management of the Western Andes. This species is susceptible to pressures such as pollution, and hunting., Estimating its distribution and abundance are essential to plan and adapt management strategies for these landscapes. Using occupancy models, we estimated occupancy of 0.52 (PI95%=0.26-0.87) with a probability of detection of 0.36 (PI95%=0.18-0.56). No effects were found on the probability of occupancy by selected covariates. We recommend extending the management and monitoring programs to a broader scale with sampling units equivalent to the home range size of the species.

Human disturbances and the daytime activity of sympatric otters along equatorial Amazonian rivers.

Previous studies suggest coexistence between sympatric neotropical (Lontra longicaudis) and giant otters (Pteronura brasiliensis) maybe facilitated by temporal and spatial differences in activity. Yet, to date there has been no systematic evaluation of activity of these species in sympatry. Here we use extensive multi-year field data to compare temporal and spatial patterns in the diurnal activity of sympatric giant and neotropical otters to answer three questions: Do temporal patterns in daytime river use change in relation to seasonal river levels (low, rising, high and declining river levels), do they change due to human disturbances (boats and fishing nets) and do patterns in neotropical otter activity change due to the presence of the larger sized giant otter? Direct observations of both species were recorded using standardized boat surveys along 218 km of rivers over 53 months during nine years (2011-2013 and 2015-2020). Complementary techniques (Generalized Additive Models, Kernel density estimates and non-parametric tests,) were used to compare diurnal activity patterns along rivers subdivided into 41 river reaches. The presence of giant otters decreased threefold from 67% of the least disturbed reaches (few boats no fishing nets) to 18% of the most disturbed reaches with many boats and fishing nets. In contrast neotropical otter presence nearly doubled from 44% of the least disturbed to 73% of the most disturbed reaches with fewest giant otter detections. Both species were observed across all daytime hours but were observed rarely on the same day. There was no evidence to suggest simultaneous use of the same reach. When species were detected on the same day, they were separated spatially (median distance between species 12.5 km) and temporally (median time difference 3.0 hours). There was little change in activity of either species among seasons. Giant otters were less active in river reaches with fishing nets and boat use, whereas neotropical otter activity did not appear to be strongly affected by these activities. Our findings support evidence that diurnal activity in both otter species is flexible, with daytime activity changing due to human disturbances in the case of giant otters.

The otter Lontra Gray, 1843 (Mustelidae, Lutrinae) in the late Pleistocene – early Holocene of Uruguay

Within the order Carnivora, mustelids represent the most diverse family worldwide, with a great ecomorphological diversity in terms of diet, size and locomotory adaptations. Among them, the subfamily Lutrinae corresponds to semiaquatic forms, in which the genus Lontra is included. Widely distributed at present day, this genus is represented by three species across South America (Lontra longicaudis, Lontra felina and Lontra provocax), however their fossil record in the continent is very scarce. In the present contribution, new fossil material assigned to the Neotropical otter Lontra cf. L. longicaudis are described from late Pleistocene – early Holocene (Lujanian Stage/Age) deposits of Uruguay (Sopas and Dolores formations). Based on these findings, some aspects related to the knowledge of the group, paleoecology and paleoenvironmental conditions are discussed.

Medium and large-sized mammals in a premontane moist forest fragment, Atenas, Costa Rica

Introduction: Medium and large-sized mammals are threatened globally due to habitat loss and fragmentation. In Costa Rica, forest fragments that remain outside protected areas may serve as a refuge or corridor for these animals. Mammal presence in fragmented landscapes may be influenced by resource availability, which varies greatly in seasonal regions. Objective: To determine the species richness of medium and large-sized mammals in a forest fragment, and to examine if species diversity and detectability varied between the wet and dry season. Methods: We established 26 camera trap stations throughout the Municipal Forest of Atenas (Alajuela, Costa Rica), a 26.4 ha forest fragment that provides water to about 1 800 people. From August 2021 to April 2022, one camera trap was active at each station for 12-21 days throughout each season (dry and wet), for a total of 810 camera trap days. We applied rarefaction and extrapolation curves to characterize mammal’s species diversity and compare it between seasons. Results: We detected 19 species of mammals. The most frequently detected species were the White-nosed Coati (Nasua narica; 0.254 detections/camera trap day), and the Central American Agouti (Dasyprocta punctata; 0.163 detections/camera trap day). We also registered four species considered as endangered in Costa Rica, three felines: Puma concolor, Herpailurus yagouaroundi, Leopardus pardalis, and the Neotropical River Otter, Lontra longicaudis. Seasonality did not affect species diversity, but it influenced dominant species and detectability, which was greater during the wet season. Conclusions: Our study demonstrates how protecting small forest fragments, can help conserve endangered medium and large-sized mammals in human-dominated landscapes. Objective: We aimed to determine the species richness of medium and large-sized mammals in a forest fragment protected for water production, and to examine if species diversity and detectability varied between the wet and dry season. Methods: We established 26 camera trap stations throughout the Municipal Forest of Atenas (MFA), a 26-ha forest fragment that provides drinking water to about 1 800 people. From August 2021 to April 2022, one camera trap was active at each station for 12-21 days throughout each season (dry and wet), for a total of 810 camera trap days. We applied rarefaction and extrapolation curves to characterize mammal’s species diversity and compare it between seasons. Results: We detected 19 species of medium and large-sized mammals. The species with the highest frequency of detections were the White-nosed Coati (Nasua narica; 0.504 detections/camera trap day), and the Central American Agouti (Dasyprocta punctata; 0.377 detections/camera trap day). We also detected four species considered as endangered in Costa Rica, three felines: Puma concolor, Herpailurus yagouaroundi, Leopardus pardalis, and the Neotropical River Otter, Lontra longicaudis. Seasonality did not affect species diversity but influenced the detectability of dominant species. Discussion: The relatively high richness of mammals observed in the MFA is likely related to the surrounding land use, which is dominated by agroforestry systems (e. g., coffee plantations) and forest patches, that may contribute to animal mobility and serve as refuge in fragmented landscapes. Conclusions: Our study demonstrates how protecting ecosystem services, such as water, may also help conserving endangered medium and large-sized mammals in fragmented landscapes.

Behaviors of the Solitary Neotropical Otter (Lontra longicaudis) in Communal Latrines

Latrines are important sites for intraspecific olfactory communication in mammals, especially for solitary or widely distributed species. Communal latrines give visitors access to information about other visitors, notably conspecific chemical cues, even in their absence. Chemical communication has evolved to allow information transfer among individuals that, due to other ecological constraints, do not co-occur in time. Latrines can be difficult to find and monitor but provide useful information about the behavioral ecology of otters. The aim of this study was to describe the behaviors of Neotropical otters (Lontra longicaudis, Olfers, 1818) in two communal latrines using video-camera traps. A total of 1,651 one-minute footage of otters visiting the latrines were used to elaborate an ethogram that included individuals (1) passing by, (2) rubbing, (3) scent marking, (4) scratching, (5) in vigilance, (6) smelling, (7) defecating, (8) urinating, (9) digging, (10) self-grooming, and (11) interacting with others. These results suggest that latrines are not only used by Neotropical otters to deposit feces and urine but that they also play a role in intraspecific communication. We suggest that L. longicaudis latrines function as information centers where individuals can monitor the location and activities of potential sexual partners and/or competitors.

The coemergence of the neotropical otter in the constructed reality of UHE Caconde

Emergy analysis can be applied to establish the relationship between the natural and the economic system, in the analysis and conservation of biodiversity and the sustainability of large bodies of water. This research aims to investigate the occurrence of neotropical otters in the UHE Caconde through a systemic analysis based on the flow of energy between the different ecological compartments. Data were obtained from several sources, including local official statistical yearbooks, inventories, dissertations, theses, published articles, and UHE Caconde reports. The intensity of the presence of the neotropical otter in the sampling sites is determined by the positive or negative record of the species and the number of excrements over time. Of the 56 points monitored, 50% reported the presence of the species. Results indicate that there was a significant difference in the number of excrement over the months. The measurement of biodiversity in joules, positions mammals first with 2.0E+23 seJ/espécie, followed by amphibians (1.3E+23 seJ/espécie), reptiles (1.0E+23 seJ/espécie), birds (5.2E+22 seJ/espécie), and fish (1.1E+22 seJ/espécie). Renewable sources are dominated by geopotential rain and transpiration, 233 and 139 million emdollars, respectively. These energy sources are followed by potential chemical rain (at em$139 million), surface water runoff (at em$98 million), and wind (at em$268 thousand). The presence of Lontra longicaudis in the lake of Caconde and its main tributaries has as its main feature the dependent origin, which results from researchers' experience and vision of the environment, and a trophic network, which follows an energy order in the system.