Short-Finned Pilot Whale Strandings Associated with Pilot Whale Morbillivirus, Brazil.

Cetacean morbillivirus (CeMV) causes illness and death in cetaceans worldwide; the CeMV strains circulating in the Southern Hemisphere are poorly known. We detected a pilot whale CeMV strain in 3 short-finned pilot whales (Globicephala macrorhynchus) stranded in Brazil during July-October 2020. Our results confirm this virus circulates in this species.

Ecologically driven differences in individual diet specialization across three populations of Guiana dolphin.

Populations usually considered foraging generalists may include specialized individuals that feed on a restricted subset of the prey spectrum consumed by the population. By analyzing the time series of δ13C and δ15N values in sequential growth layer groups within tooth dentin, we measured population- and individual-level variation in resource use of three populations of Guiana dolphins (Sotalia guianensis)-Caravelas River, Babitonga Bay, and Norte Bay-along a latitudinal gradient in the southwestern Atlantic Ocean. We show that the Guiana dolphin at Caravelas River is a generalist population consisting of individual dietary specialists, likely due to the absence of other resident dolphin populations thus allowing individuals to target prey across a wide range of habitats. The Babitonga Bay population is also composed of individual specialists potentially due to the selective foraging behavior of some individuals on high-quality prey sources within and near the bay. In contrast, the Norte Bay population comprises individual generalists, which likely reflects its distinctive cohesive social organization, coexistence with two other dolphin species, and an opportunistic foraging strategy in response to resource fluctuations inherent to the southern limit of the species distribution. Although the Guiana dolphin is generally considered to be a dietary generalist at the population level, our findings reveal that the total niche width of populations and the degree of individual diet specialization are highly context dependent, suggesting dietary plasticity that may be related to a latitudinal gradient in resource availability and environmental conditions.

Microsatellite markers for the endangered franciscana dolphin (Pontoporia blainvillei).

The franciscana (Pontoporia blainvillei) is the most threatened small cetacean in the South Atlantic. In this study we report the development of 13 microsatellite markers for franciscanas through next-generation sequencing, and the characterization of those loci in 38 samples from the species' northernmost population (Espírito Santo, Brazil). Besides providing diversity indices for the new, specific loci, we also report on the transferability of heterologous loci which had not been screened in franciscanas before, and review all loci used in previous studies. Expected heterozygosity in the new loci ranged between 0.107 and 0.595, and all but one were in Hardy Weinberg Equilibrium. These are the first microsatellite loci isolated from franciscanas, and they are an important addition to heterologous markers that were available previously.

Ascocotyle longa (Digenea: Heterophyidae) infecting dolphins from the Atlantic Ocean.

We report for the first time the infection of dolphins with Ascocotyle longa found in the intestines of three different species, Sotalia guianensis, Steno bredanensis, and Tursiops truncatus gephyreus, which were found washed ashore along the southeastern and southern Brazilian coast. The worms were identified based on morphological and molecular data using the 28S rDNA gene and the COI gene. Specimens of A. longa from the pinniped Otaria flavescens were also analyzed. As the first isolation of A. longa from cetaceans, the present study increases the distribution area and range of definitive hosts of this trematode, and provides new molecular data to complement the phylogeny of the group in future studies, thus contributing to the scientific knowledge of this potentially zoonotic parasite.

Echolocation variability of franciscana dolphins (Pontoporia blainvillei) between estuarine and open-sea habitats, with insights into foraging patterns.

Environmental and ecological factors can trigger changes in the acoustic repertoire of cetaceans. This study documents the first use of a well-established passive acoustic monitoring device (C-POD) to analyze echolocation sounds and behavior of franciscana dolphins in different habitats: estuary [Babitonga Bay (BB)] and open sea [Itapirubá Beach (IB)]. A total of 10 924 click trains were recorded in BB and 6 093 in IB. An inter-click interval < 10 ms (so called "feeding buzzes") was used as a proxy for foraging activity. The main difference in the acoustic parameters between the two habitats was related to the frequency spectrum, with higher maximum and lower modal and minimum click frequencies in BB, and a train frequency range of 17 kHz, against 10 kHz in IB. Also, the click emission rate (clicks/s) was almost 20% higher in BB. Both studied habitats showed a high proportion of feeding buzzes (BB = 68%; IB = 58%), but with a higher probability of occurrence in BB (p < 0.001) and at night (p < 0.001) in both habitats. The C-PODs showed great potential to monitor occurrence, bioacoustics parameters, and echolocation behavior of franciscana dolphins. Longer-term temporal and spatial monitoring are necessary for elucidating several issues raised in this study.

Plasmodium infection and its association with biochemical and haematological parameters in free-living Alouatta guariba clamitans (Cabrera, 1940) (Primates: Atelidae) in Southern Brazil.

BACKGROUND: The influence of Plasmodium spp. infection in the health of Southern brown howler monkey, Alouatta guariba clamitans, the main reservoir of malaria in the Atlantic Forest, is still unknown. OBJECTIVES: The aim of this study was to investigate the positivity rate of Plasmodium infection in free-living howler monkeys in an Atlantic Forest fragment in Joinville/SC and to associate the infection with clinical, morphometrical, haematological and biochemical alterations. METHODS: Molecular diagnosis of Plasmodium infection in the captured monkeys was performed by Nested-polymerase chain reaction (PCR) (18S rRNA and coxI). Haematological and biochemical parameters were compared among infected and uninfected monkeys; clinical and morphometrical parameters were also compared. FINDINGS: The positivity rate of Plasmodium infection was 70% among forty captured animals, the highest reported for neotropical primates. None statistical differences were detected in the clinical parameters, and morphometric measures comparing infected and uninfected groups. The main significant alteration was the higher alanine aminotransferase (ALT) levels in infected compared to uninfected monkeys. MAIN CONCLUSIONS: Therefore, Plasmodium infection in howler monkeys may causes haematological/biochemical alterations which might suggest hepatic impairment. Moreover, infection must be monitored for the eco-epidemiological surveillance of malaria in the Atlantic Forest and during primate conservation program that involves the animal movement, such as translocations.

Pulmonary and systemic fungal infections in an Atlantic spotted dolphin and a Bryde's whale, Brazil.

We report the gross and microscopic findings and molecular identification of 2 cases of hyphate fungal infection in cetaceans from Brazil. The first case involved an adult male Atlantic spotted dolphin Stenella frontalis with localized pulmonary disease characterized by pyogranulomatous and necrotizing bronchopneumonia with intralesional hyphae. The second case involved an adult male Bryde's whale Balaenoptera edeni with orchitis, periorchitis, mesenteric lymphadenitis and pyogranulomatous bronchopneumonia with intralesional hyphae. PCR analysis from the dolphin's lung yielded Aspergillus fumigatus, and the fungus from the whale's mesenteric lymph node showed the greatest identity to Nanniziopsis obscura and Stagonosporopsis cucurbitacearum These cases represent the first reports of pulmonary aspergillosis by A. fumigatus in an Atlantic spotted dolphin and systemic mycosis by a possibly novel Onygenales in marine mammals.

A new Synthesium species (Digenea: Brachycladiidae) from the bottlenose dolphin Tursiops truncatus (Cetacea: Delphinidae) in Southwestern Atlantic waters.

A new species of Synthesium from the bottlenose dolphin Tursiops truncatus in South Brazilian waters is described. Morphological and molecular identification was performed, and phylogenetic analyses were carried out using the ribosomal small subunit and internal transcribed spacer 1 and the mitochondrial NDH dehydrogenase subunit 3 and cytochrome c oxidase subunit 1 genes. The main characteristics of the new species are the subterminal round-shaped oral sucker, the anterior distribution of vitellaria reaching the level of the ovary and the oval-shaped testes. The results obtained with the molecular markers supported the inclusion of the specimens into the genus Synthesium. The nucleotide divergence detected for the mitochondrial genes among the new species and others of the same genus supported the erection of a new species. This is the ninth species assigned to the genus and the third Synthesium species recorded in the South Atlantic Ocean.

Social sounds produced by franciscana dolphins, Pontoporia blainvillei (Cetartiodactyla, Pontoporiidae).

Franciscana dolphin (Pontoporia blainvillei) whistles were documented for the first time during 2003-2013 in Babitonga Bay estuary, South Brazil, together with burst pulses. Recordings were made from small boats under good sea conditions, and recording equipment that allowed analysis of sounds up to 96 kHz. The recordings were made in the presence of 2-31 franciscana dolphins. During 23 h and 53 min, 90 whistles and 51 burst pulse series were recorded. Although Guiana dolphins (Sotalia guianensis) inhabit nearby waters, none were observed in the area during the recordings. The authors recorded ten types of whistles. The initial frequency varied between 1.6 and 94.6 kHz, and the final frequency varied between 0.7 and 94.5 kHz; the authors were not able to determine if dolphin whistles exceeded the 96 kHz recording limit of the authors' equipment, although that is likely, especially because some whistles showed harmonics. Whistle duration varied between 0.008 and 0.361 s. Burst pulses had initial frequencies between 69 and 82.1 kHz (77 ± 3.81). These results showed that P. blainvillei produces whistles and burst pulses, although they seem to be produced infrequently.

First record of an anomalously colored franciscana dolphin, Pontoporia blainvillei.

On October 2011, a newborn franciscana dolphin with an anomalously coloration was sighted in Babitonga Bay, southern Brazil. The calf was totally white. Besides the potential mother and newborn, the group also had the presence of another adult, who always was swimming behind the pair. Both adults had the typical coloration of the species, with the back in grayish brown. The group, composed by the white franciscana calf, his pontential mother and one more adult, was reported in five occasions. The group was always in the same area where it was first recorded and showed the same position during swimming. Between first and last sighting of the white calf (113 days) the color has not changed. This is the first case of a white franciscana dolphin. This coloration has never been reported despite the high number of dead franciscanas recovered each year along the distribution of the species, resulting from accidental capture in fishing nets. This fact leads us to believe that this is a very rare characteristic for this species. We considered the possibility that this franciscana could be an albino dolphin.

First determination of UV filters in marine mammals. Octocrylene levels in Franciscana dolphins.

Most current bioexposure assessments for UV filters focus on contaminants concentrations in fish from river and lake. To date there is not information available on the occurrence of UV filters in marine mammals. This is the first study to investigate the presence of sunscreen agents in tissue liver of Franciscana dolphin (Pontoporia blainvillei), a species under special measures for conservation. Fifty six liver tissue samples were taken from dead individuals accidentally caught or found stranded along the Brazilian coastal area (six states). The extensively used octocrylene (2-ethylhexyl-2-cyano-3,3-diphenyl-2-propenoate, OCT) was frequently found in the samples investigated (21 out of 56) at concentrations in the range 89-782 ng·g(-1) lipid weight. São Paulo was found to be the most polluted area (70% frequency of detection). Nevertheless, the highest concentration was observed in the dolphins from Rio Grande do Sul (42% frequency of detection within that area). These findings constitute the first data reported on the occurrence of UV filters in marine mammals worldwide.

Redescription of Leptoconops (Leptoconops) brasiliensis (Lutz) and Leptoconops (Megaconops) floridensis Wirth (Diptera: Ceratopogonidae) with its first Brazilian record.

The Leptoconops Skuse genus includes many pestiferous biting midges found in coastal areas. Only two species were previously found in Brazil and some species have ancient descriptions lacking updated taxonomic features. Herein, we redescribe Leptoconops (Leptoconops) brasiliensis Lutz and L. (Megaconops) floridensis Wirth based on female type specimens and additional material from Gois and Santa Catarina, Brazil. The first Brazilian record of L. (M.) floridensis is reported.

The deep dive of organohalogen compounds: Bioaccumulation in the top predators of mesopelagic trophic webs, pygmy and dwarf sperm whales, from the Southwestern Atlantic ocean.

Kogia sima and Kogia breviceps are apex predators of mesopelagic trophic webs being far from most anthropogenic threats. However, chemical pollutants and naturally synthesized compounds may travel long distances. This study aimed to use kogiid whales as sentinels of mesopelagic trophic webs in the Southwestern Atlantic Ocean. Persistent organic pollutants (POPs), e.g., polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and metabolites, mirex, hexachlorobenzene (HCB), polybrominated diphenylethers (PBDEs), pentabromoethylbenzene (PBEB) and hexabromobenzene (HBB), and the naturally produced methoxylated BDE (MeO-BDEs) were determined in the blubber of 16 K. sima and 15 K. breviceps. Among the organochlorine compounds, DDTs were the main group found in K. sima and in K. breviceps (1636.6 and 3983.3 ng g-1 lw, respective medians), followed by PCBs (425.9 and 956.1 ng g-1 lw, respectively), mirex (184.1 and 375.6 ng g-1 lw, respectively), and HCB (132.4 and 340.3 ng g-1 lw, respectively). As for the organobromine, the natural MeO-BDEs were predominant (1676.7 and 501.6 ng g-1 lw, respectively), followed by PBDEs (13.6 and 10.3 ng g-1 lw, respectively) and PBEB (2.2 and 2.9 ng g-1 lw, respectively). In general, POPs concentration was higher in K. breviceps than in K. sima. Conversely, MeO-BDEs concentration was higher in K. sima than in K. breviceps. Differences in concentrations in these sympatric odontocetes were attributed to distinct species, sampling sites, and biological parameters and suggest some level of niche segregation. It is noteworthy the long-range reach and bioaccumulation of these synthetic compounds in an unexplored habitat, that present an increasing economic interest.

Brominated flame retardants and natural organobrominated compounds in a vulnerable delphinid species along the Brazilian coast.

Guiana dolphins, Sotalia guianensis, are vulnerable to extinction along their distribution on the Brazilian coast and assessing chemical pollution is of utmost importance for their conservation. For this study, 51 carcasses of Guiana dolphins were sampled across the Brazilian coast to investigate legacy and emerging brominated flame retardants (BFRs) as well as the naturally-produced MeO-BDEs. PBDEs and MeO-BDEs were detected in all samples analyzed, whereas emerging BFRs were detected in 16 % of the samples, all in Rio de Janeiro state. PBDE concentrations varied between 2.24 and 799 ng.g-1 lipid weight (lw), emerging BFRs between 0.12 and 1.51 ng.g-1 lw and MeO-BDEs between 3.82 and 10,247 ng.g-1 lw. Concentrations of legacy and emerging BFRs and natural compounds varied considerably according to the sampling site and reflected both the local anthropogenic impact of the region and the diversity/mass of biosynthesizers. The PBDE concentrations are lower than what was found for delphinids in the Northern Hemisphere around the same sampling period and most sampling sites presented mean concentrations lower than the limits for endocrine disruption known to date for marine mammals of 460 ng.g-1 lw, except for sampled from Santa Catarina state, in Southern Brazil. Conversely, MeO-BDE concentrations are higher than those of the Northern Hemisphere, particularly close to the Abrolhos Bans and Royal Charlotte formation, that are hotspots for biodiversity. Despite the elevated concentrations reported for this group, there is not much information regarding the effects of such elevated concentrations for these marine mammals. The distinct patterns observed along the Brazilian coast show that organobrominated compounds can be used to identify the ecological segregation of delphinids and that conservation actions should be planned considering the local threats.

Characterization of Traumatic Injuries Due to Motor Vehicle Collisions in Neotropical Wild Mammals.

Motor vehicle collisions (MVCs) are a severe threat to wildlife biodiversity worldwide and most vertebrate species are at risk. However, there is a considerable knowledge gap on the traumatic features and potential patterns of MVCs in wildlife. We investigated traumatic injuries (TIs) caused by MVCs (MVCs-TIs) in 430 neotropical wild mammals representing 44 species from Brazil. Injuries were classified topographically into four categories: abdomen/pelvis (AP), chest (TX), head/neck (HN) and extremities (EX). We also determined the prevalence of pathological changes in MVC fatalities. AP (n = 381; 89%) was the most affected body segment, followed by TX (n = 372; 87%), HN (n = 363; 84%) and EX (n = 288; 67%). The most prevalent gross pathological findings were single or multiple bone fractures (n = 397; 92%), visceral organ rupture (n = 371; 86%), haemothorax (n = 220; 51%) and pulmonary haemorrhage (n = 212; 49%). Microscopically, pulmonary oedema (n = 324; 82%) and haemorrhage (n = 272; 69%) were the most prevalent lesions. No distinct TI patterns were evident across the various taxonomic groups, although trends were found in some taxa, such as armadillos. These results may help clinicians performing emergency care on MVC wildlife patients and may be of value in pathological and forensic investigations where a MVC has been deemed a likely contributory factor to death.

Low-frequency sampling rates are effective to record bottlenose dolphins.

Acoustic monitoring in cetacean studies is an effective but expensive approach. This is partly because of the high sampling rate required by acoustic devices when recording high-frequency echolocation clicks. However, the proportion of echolocation clicks recorded at different frequencies is unknown for many species, including bottlenose dolphins. Here, we investigated the echolocation clicks of two subspecies of bottlenose dolphins in the western South Atlantic Ocean. The possibility of recording echolocation clicks at 24 and 48 kHz was assessed by two approaches. First, we considered the clicks in the frequency range up to 96 kHz. We found a loss of 0.95-13.90% of echolocation clicks in the frequency range below 24 kHz, and 0.01-0.42% below 48 kHz, to each subspecies. Then, we evaluated these recordings downsampled at 48 and 96 kHz and confirmed that echolocation clicks are recorded at these lower frequencies, with some loss. Therefore, despite reaching high frequencies, the clicks can also be recorded at lower frequencies because echolocation clicks from bottlenose dolphins are broadband. We concluded that ecological studies based on the presence-absence data are still effective for bottlenose dolphins when acoustic devices with a limited sampling rate are used.

Total tin (TSn) biomagnification: Evaluating organotin trophic flow and dispersion using hepatic TSn concentrations and stable isotope (C, N) data of nektonic organisms from Brazil.

A previous investigation of our research team has demonstrated the suitability of using hepatic total tin (ΣSn) concentrations for evaluating dolphin exposure to organotins (OTs). The present study develops the previous technique into three different approaches that comprise data: (1) on hepatic ΣSn concentrations of 121 Guiana dolphins (Sotalia guianensis) from five different coastal areas (CAs): (2) on ΣSn, δ13C and δ15N for 40 dolphins from Rio de Janeiro state (RJ), including ten different delphinid species; as well as (3) on hepatic ΣSn concentrations and δ15N values on 31 individuals from five different fish species from Sepetiba Bay (SB, Rio de Janeiro-RJ, Brazil). Hepatic ΣSn concentrations of Guiana dolphins from Guanabara Bay (GB, RJ) were significantly higher than those found in other four CAs from S and SE Brazilian regions. Significant positive correlations were found between ΣSn concentrations and δ13C data in delphinid species, demonstrating a coast-ocean gradient in dolphin exposure to OTs in RJ state. Significant and positive correlations were observed between ΣSn concentrations and both δ15N and Trophic Position (TP) values of fish, as well as high values were found for Trophic Magnification Factor (TMF = 3.03) and Trophic Magnification Slope (TMS = 0.14), demonstrating OT biomagnification in SB ichthyofauna.

Pyrethroid insecticides along the Southwestern Atlantic coast: Guiana dolphin (Sotalia guianensis) as a bioindicator.

The presence of pyrethroid compounds in hepatic tissue of Guiana dolphins (Sotalia guianensis) is reported for the first time. Twelve pyrethroids were determined in 50 animals from eight locations of the Brazilian coast. The highest average concentration of total pyrethroids (∑PYR) was 1166 ng.g-1 lw, with values ranging from 148 to 5918 ng.g-1 lw, in Ilha Grande Bay, Rio de Janeiro State, while the Espírito Santo State had the highest median, 568 ng.g-1 lw. Permethrin was the predominant compound in most areas, contributing for 42% to 81% of the ∑PYR, whereas cypermethrin was the most abundant compound in Guanabara and Sepetiba bays (79% and 81%, respectively), both located in Rio de Janeiro State. Biological factors were not correlated with pyrethroids concentration. Tetramethrin and es/fenvalerate compounds were negatively correlated to the age, suggesting degradation/metabolization capacity in these animals that increases throughout life. Despite being metabolized and excreted, the wide use of these pollutants is reflected in relevant concentrations found in Guiana dolphins. This is the first study evaluating pyrethroids in a representative number of hepatic samples and covering >2600 km of coast. The overall lack of information on pyrethroids in cetaceans highlights the importance of understanding the profile and distribution of these pollutants in dolphins which exclusively inhabit the Southwestern Atlantic coast.

Fatal pulmonary parafilaroidiasis in a free-ranging subantarctic fur seal (Arctocephalus tropicalis) coinfected with two gammaherpesviruses and Sarcocystis sp.

A juvenile subantarctic fur seal (Arctocephalus tropicalis) found dead in Santa Catarina state, southern Brazil, presented with disseminated verminous pneumonia due to Parafilaroides sp. A concomitant infection with two different gammaherpesviruses was identified by PCR in different tissues; one of them possibly a novel species (tentatively named Otariid herpesvirus 7). Sarcocystis sp. DNA was identified molecularly in skeletal muscle samples with intrasarcoplasmic bradyzoites and no apparent tissue response. All analyzed samples (mandibular, laryngeal, tracheal, and mesenteric lymph nodes, and lung) were PCR-negative for Brucella spp. The most likely cause of death was severe pulmonary parafilaroidiasis. The pathogenic role of the gammaherpesviruses in several of the tissues was not evident. This study describes the pathogenicity of Parafilaroides sp. in a subantarctic fur seal, widens the host range of herpesvirus in pinnipeds, and reports the first molecular identification of Sarcocystis sp. in this species.

Novel herpesviruses in riverine and marine cetaceans from South America.

Herpesvirus (HV) infections in cetaceans are frequently associated with skin and mucosal lesions. Although HV infections have been reported worldwide, their occurrence in southern Atlantic marine mammals is still poorly understood. We tested skin, oral and genital mucosal beta-actin PCR-positive samples from 109 free-ranging Brazilian cetaceans using a universal herpesvirus DNA polymerase PCR. Herpesvirus-positive skin samples from a Guiana dolphin (Sotalia guianensis), a dwarf sperm whale (Kogia sima), a Bolivian river dolphin (Inia boliviensis), and a lingual sample from an Atlantic spotted dolphin (Stenella frontalis) were histologically evaluated. Additional tissue samples from these animals were also PCR-positive for HV, including a novel sequence obtained from the dwarf sperm whale's stomach and mesenteric lymph node. Four novel HV species were detected in the Guiana dolphin (one), the dwarf sperm whale (two) and the Bolivian river dolphin (one). The cutaneous lesions (marked, focally extensive, chronic proliferative dermatitis) of the Guiana dolphin and the Bolivian river dolphin were similar to previous HV reports in cetaceans, despite the absence of intranuclear inclusion bodies. This is the largest HV survey in South American cetaceans and the first detection of HV infection in riverine dolphins worldwide.