Latin American Journal of Aquatic Mammals (LAJAM)
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Epidemiological characteristics of skin disorders in cetaceans from South American waters
No full textWe document the macroscopic phenotypic characteristics (relative size, location, pattern, colour, extension), prevalence and evolution of five types of skin disorders of unknown aetiology, including ‘green-brown plaques’ (GBP), ‘orange patches’ (OPA), ‘cutaneous nodules’ (NOD), ‘pale dermatitis’ (PAD) and ‘expansive annular lesions’ (EAL) in five odontocete species (n = 559 individuals) from the Southeast Pacific (n = 230) and Southwest Atlantic (n = 329) oceans. GBP affected two likely-adult Sotalia guianensis traveling side-by-side in a freshwater area of the Cananéia Estuary in August 2009. Low salinity is suggested as predisposing factor. OPA were distinguished in three of 209 (1.4%) free-ranging S. guianensis in Sepetiba Bay, Brazil, during winter months of 2005-2008. Epibiont diatoms are suspected aetiological agents. NOD were chronically present in one male adult Orcinus orca observed off the coast of southern Brazil in 2007-2010. PAD was seen in free-ranging individuals and carcasses of Tursiops truncatus, S. guianensis and Pseudorca crassidens from both the Atlantic and Pacific Oceans in 1992 and in 2004-2009. Prevalence was 1% in 103 S. guianensis from Paranaguá Estuary (Brazil), 2.3% in 222 S. guianensis from Sepetiba Bay and 6.9% in 87 inshore T. truncatus from Paracas Bay, Peru. Although in some cases the lesions covered up to 35-40% of the visible body surface and ulcers may occur there was no evidence of mortality and, in time-series of six individuals, PAD eventually healed. In six T. truncatus and five S. guianensis acutely affected, PAD was associated with minor cutaneous injuries and scars, including tooth rakes, suggesting infection routes for opportunistic pathogens. EAL were noted in a Cephalorhynchus eutropia calf from Palena province, Chile, in 2003 and in a P. crassidens calf washed ashore dead in southern Brazil in 2009. The C. eutropia calf disappeared, and probably died, two weeks after first observation. Prevalence of EAL was 6.7% in 15 C. eutropia in 2002-2004. These data suggest that EAL are potentially lethal in calves. PAD and EAL were primarily seen in cetaceans inhabiting biologically or chemically contaminated nearshore waters. In view of their emergence and occasional severity these disorders should be the subject of systematic monitoring
Cub biometry, litter size and reproductive period of giant oters (Pteronura brasiliensis) at the Balbina Hydroelectric Reservoir, Amazonas, Brazil
No full textAccording to the literature, giant otters produce one to six cubs at each gestation, with birth peaks occurring from the end of the flood season to the beginning of the low-water period. With the aim of describing some reproductive parameters of the giant otters living in a hydroelectric lake, 56 field excursions to Balbina Hydroelectric Reservoir, hereafter Balbina Lake, were carried out between September 2001 and September 2010 in order to gather information about cub weight and length, litter size and reproductive period of the species in that area. About 80% of the birth records occurred between September and December, characterized by the receding water season and the beginning of the dry season. The number of cubs per gestation varied from one to three animals (mean = 2; n = 36) and average weight and length of neonates were 316.25 ± 64.21g (n = 4) and 31.75 ± 4.86cm (n = 4), respectively. The reproductive period and the litter size produced by giant otters in Balbina Lake were within the range reported in literature for non-dammed areas, indicating that these reproductive parameters were not changed by the reservoir. The weight of cubs analyzed in the reservoir was in average 35% greater than the weight of captive newborn cubs reported in the literature. However, as the animals here analyzed were healthy, it is reasonable to assumethat they represent the weight of free-ranging newborn cubs. Artificial lakes had been reported in the literature as favorable environments for giant otters in Guyana, and the results obtained here seem to corroborate this hypothesis and show the plasticity of the species in its use of different habitats as long as the habitats are inside some category of protection, in this way minimizing additional impacts caused by an intense human occupation of the area.
First giant otter distribution survey in the southeast of Roraima, Brazil, with notes on the OSG Guidelines for a Standardization of Survey Methods
No full textA distribution survey of giant otter was conducted for the first time in the southeast corner of Roraima, bordering the state of Amazonas, in Brazil (1° 4' S, 61°36' O). The region has recently been recognized as a protected area and is currently elaborating its own management plan. Our survey was carried out according to the guidelines for a standardisation of survey methods as recommended by the IUCN/SSC Otter Specialist Group. The short expedition covered two squares of 100x100km on the UTM grid and interested tree different river basins, investigating black-water as well as white-water watercourses. With the aim of contributing to the optimisation of the standard survey methodology, we carried out some field tests during the survey and present the results in this paper. The expedition revealed the presence of giant otter in all the basins investigated and recorded a series of human activities that may represent a threat to the species survival in the future. Although the results presented are preliminary, we discuss the implication of the presence of the giant otter in the region from a conservation perspective and provide suggestions for the protected area management plan
Negative interactions between giant otters (Pteronura brasiliensis) and local fisheries in the Amazon and Orinoco basins in Colombia
No full textThe apparent population recovery of giant otters during the last ten years in the Amazon and Orinoco basins in Colombia is creating serious conflicts between local fisheries and this species. This paper presents evidence of conflicts in the Orinoco, Meta and Bita rivers in the Orinoco basin, in the Inírida and Guaviare rivers, and in the Caquetá, Putumayo and Amazon rivers in the Amazon region. In most cases, fishermen are killing giant otters or are asking the government authorities to take action to reduce their numbers. Preliminary evaluations of giant otter diets indicated little competition with local fisheries. However, areas with more intense conflicts corresponded to regions with strong fishing pressure and bad management practices. We conclude that interference with fisheries by giant otters is relatively low but it is necessary to undertake management of the fisheries in the region to avoid perceived conflicts.
Occurrence of Cuvier’s beaked whales (Ziphius cavirostris) at Guadalupe Island, Mexico, from 2006 to 2009
No full textCuvier’s beaked whale (Ziphius cavirostris) is the most widely distributed species of beaked whale, with a cosmopolitan distribution throughout almost all temperate, subtropical and tropical waters of the world as well as subpolar and even polar waters in some areas. Globally, it may also be the most abundant species of beaked whale within the family Ziphiidae. However, there is little information on local distribution in many areas around the world. Before 2009, no dedicated research on beaked whales occurred in Guadalupe Island. In this note, we report opportunistic sightings of Cuvier’s beaked whales recorded during a white shark research project from 2006 through 2008, and the results obtained in 2009 during a pilot study focused on the beaked whales of Guadalupe Island
Editorial
No full textThe contents of Vol. 10, No. 1 are introduced, along with recent news for LAJAM's readership
A case study of artificial feeding of an unweaned giant otter (Pteronura brasiliensis) cub
No full textThere is no information available on the nutritional content of giant otter milk, nor about the amount of milk consumed by the cubs. The information presented here is intended to help ex situ institutions to raise and rehabilitate giant otter orphan cubs with an artificial milk formula and provide hand-rearing information for their management in captivity
First successful capture and satellite tracking of a West Indian manatee (Trichechus manatus) in Panama: feasibility of capture and telemetry techniques
No full textIt is currently unknown how important the Central American countries south of Belize are as a link between manatee populations in the north (Belize and Mexico) and populations in South America. Therefore, apart from knowing where manatees are found, it is important to understand how manatees are using these habitats and if they are moving between countries or distinct population centers. Here we report the results of a multi-national and multiinstitutional collaboration resulting in the first successful capture and satellite tracking of a West Indian manatee in southern Central Americ
Cetaceans observed in Suriname and adjacent waters
No full textVery little information exists about the cetaceans in the Guianas: Suriname and its neighboring countries Guyana and French Guiana. During a dedicated cetacean survey carried out from a geophysical seismic survey vessel in the offshore waters of Suriname (May-September 2012), the occurrence of 13 cetacean species was documented and of those, 11 were newly documented for this area. The species observed by the author included sperm whale (Physeter macrocephalus), Bryde’s whale (Balaenoptera edeni), false killer whale (Pseudorca crassidens), melon-headed whale (Peponocephala electra), roughtoothed dolphin (Steno bredanensis), long-beaked common dolphin (Delphinus capensis), Fraser’s dolphin (Lagenodelphis hosei), pantropical spotted dolphin (Stenella attenuata) and spinner dolphin (Stenella longirostris). During transit to the survey area (Trinidad to Suriname) incidental sightings were recorded which included common bottlenose dolphin (Tursiops truncatus) off Trinidad, Stenella sp. off Guyana and Guiana dolphin (Sotalia guianensis) at the entrance of the Suriname River. Opportunistic records originating from the periods December 2008-March 2009 and August-October 2012 were forwarded to the author. These records included common bottlenose dolphin, Atlantic spotted dolphin (Stenella frontalis) and short-finned pilot whale (Globicephala macrorhynchus). There is a growing need to identify critical areas for marine biodiversity conservation, both locally and regionally. This paper describes the general occurrence of the cetacean community encountered in Suriname waters in summer. The study revealed that the offshore cetacean community in Suriname is best described as primarily a tropical community, dominated by odontocetes (dolphins and sperm whales). Although the species diversity was relatively high, the overall cetacean relative abundance index (number of animals per 100km effort) was low, which is consistent for tropical equatorial offshore waters. Apart from the sperm whale and the Guiana dolphin, all the other species recorded represent new species records for Suriname. It is recommended that more continuous monitoring in different seasons be carried out in order to gain a better understanding of the occurrence, distribution and status of the different cetacean species within the region.
Rae Natalie Prosser de Goodall 1935-2015
No full textAn obituary on Rae Natalie P. Goodall is presented with highlights to her scientific life