Latin American Journal of Aquatic Mammals (LAJAM)
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To eat or not to eat: ingestion and avoidance of fecal content from communal latrines of Lontra longicaudis (Olfers, 1818)
No full textCommunal latrines have important biological and ecological roles for the latrine builder species and for other taxa that visit these sites and use feces to obtain nutrients and microorganisms that aid in digestion of compounds hard to process. Nonetheless, coprophagous animals must deal with the costs associated with parasites and other pathogenspresent in latrines. Parasites and pathogens are found in Neotropical otter latrines. This species is carnivorous and uses latrines for territorial marking. The objective of this study was to identify vertebrate species associated with otter latrines and species that use feces as food resource. Latrines were monitored with camera traps on a monthly basis in 24-hour cycles. We recorded nine species of vertebrates, including birds, reptiles and mammals, visiting the latrines. Feeding dependency from latrines in the Atlantic Forest may not be related to periods of low food availability (dry season). Visitors that ate at the latrines do not have the same feeding habits as otters. The assumption that mammals would avoid ingesting disease-loaded feces from latrines did not hold, since two mammal species did. We speculate these mammals might be more resistant or less susceptible to pathogens found in otter feces
First stranding record of Kogia sima (Owen, 1866) in the Colombian Caribbean
No full textThe dwarf sperm whale, Kogia sima, is one of the lesser known Odontoceti species, in spite of its worldwide distribution, and is considered rare due to the difficult identification in the field. Detailed information is scarce and mostly comes from stranding events or bycatch animals, just a few sightings correspond to live specimens. In the Caribbean Basin, the species has been reported in the Lesser Antilles, Mexico, Honduras, Costa Rica and Venezuela. We present the first stranding record of Kogia sima in the Colombian Caribbean coast from a pregnant female in Mendihuaca region, Magdalena Department. The specimen showed no fishing or entanglement lines whatsoever, and the overall condition was good. Morphological measurements were taken and the confirmation of the species was made from the following features: body length, height and position of dorsal fin, position of blowhole, and number of teeth in the lower jaw. The record of the adult specimen is documented in the System of Information of Marine Biodiversity of Colombia –SIBM and the fetus is deposited in the Mammal collection of the Museum of Marine Natural History of Colombia –MAKURIWA under the catalogue number INV-MAM004
Intensive feeding of humpback whales (Megaptera novaeangliae) in the breeding ground of Banderas Bay, Mexico
No full textBanderas Bay, located in the Mexican Pacific, is a breeding/calving ground for the North Pacific stock of humpback whales (Megaptera novaeangliae) during the winter. While sporadic registers of humpback whales feeding on their mating grounds exist, this is the first occasion where feeding activity was observed intensively and extensively on a breeding ground. Between 19 December 2011 and 6 March 2012, 26 such occurrences were registered in Banderas Bay, along the mainland pacific coast. On five occasions, groups of 20 or more individuals were recorded feeding. They were feeding over and under the surface using lunging and gulping techniques. On several occasions humpbacks were observed feeding alongside Bryde´s whales (Balaenoptera edeni), Pantropical spotted dolphins (Stenella attenuata) and Bottlenose dolphins (Tursiops truncatus). Two different samples of fish at two different feeding sites were taken and the fish identifications showed these were Pacific anchovies (Cetengraulis mysticetus). Among the 26 sightings, nine different species of birds were registered feeding in the same area as the humpback whales. The number of whales feeding over an extended period of time in their breeding ground could be an indicator that there was not enough food in their feeding grounds, but the possibility that they might just be taking advantage of good food availability is also possible
First stranding record of a Cuvier’s beaked whale (Ziphius cavirostris) on the island of Barbuda, Eastern Caribbean
No full textCuvier's beaked whale is the most cosmopolitan of the beaked whales and is found in all oceans except in the high polar waters. This species is known from over 1800 strandings. In the Caribbean strandings are rare, and we present a first record from Antigua and Barbuda
New non-breeding colonies of the South American fur seal in central Chile. Is the distribution in the southeastern Pacific waters extending?
No full textThe South American fur seal (SAFS), Arctocephalus australis, has an estimated abundance of 219,000 individuals. The distribution range of this top marine predator along the Pacifc coast of South America is discontinuous, with a gap between 29°02’S-43°36’S, whereas the Atlantic coast presents a continuous distribution. Little is known aboutthe population dynamics of the species in Chile, as there have been few observations of vagrant individuals within the distribution gap and partial population censuses on dates that do not fit with the reproductive season in northern andsouthern Chile. The aim of this study is to identify the presence of A. australis colonies and summarize the sightings in central Chile. Aerial censuses were performed between 32°12’S-39°24’S during the austral winter and summer (2015) and between 41°44’S-44°55’S during summer (2013, 2016-2018). Official stranding records were also included to complementthe research sightings. We registered a total of 54 SAFS in the Chilean distribution gap, most of them during winter (89%) and with a higher proportion of females (72%). Two non-breeding colonies were found in the Biobío Region during the winter of 2015, Islote del Trabajo (38°25’S) and Islote Quechol (38°26’S), with 27 ± 1 and 16 ± 0 individuals, respectively. The sightings of adult individuals suggest their arrival at these latitudes to carry out foraging and resting activities, probably from Guafo Island (43°36’S). The last Pleistocene glaciation, hunting activities during the eighteenth century and ENSO events could have conditioned the current abundance and range of distribution of A. australis in South America; therefore, the establishment of new non-breeding colonies in the gap of distribution could lead to new breeding grounds in thefuture
The use of underwater viewing deck of the semi-submersible whalewatching vessel Yellow Submarine at Península Valdés, Argentina as a platform of opportunity for scientifc research with the southern right whale, Eubalaena australis
No full textWhale-watching vessels can be used as platforms to collect scientific data on the natural history of cetaceans. Vessels with underwater viewing decks are exceptional and offer a unique view of the whales. We assessed the underwater viewing platform of the semi-submersible vessel Yellow Submarine that operates off Puerto Pirámides, Península Valdés, Argentina as a platform of opportunity for southern right whale (Eubalaena australis) research. The variables considered during observations included, among others, the age class and sex of the animals observed, behavioral patterns, opportunities for individual photo-identification, distance and duration of the underwater observations and how weather conditions affected data collection. The Yellow Submarine offers a unique platform to make underwater observations of southern right whales in this calving ground. The main limitations are the relatively short duration of the observations and reduced visibility in spring
Opportunistic feeding experiment in a captive franciscana (Pontoporia blainvillei): assessing gastrointestinal transit time and gastric digestion.
No full textThe data consists of spreadsheets containing (i) otolith and cephalopod beak numbers and sizes, and the time of recovery for seven different prey species of different meals; (ii) conditions of prey structures for each meal and its time of recovery; and (iii) the times that the plastic colour markers were ingested and evacuated from a feeding experiment with a franciscana dolphin in captivity
Rare and antagonistic interactions between short-finned pilot whales (Globicephala macrorhynchus and fasting humpback whales (Megaptera novaeangliae) off Western Puerto Rico
No full textThe authors describe antagonistic interactions between short-finned pilot whales (Globicephara machrorhyncus) and humpback whales (Megaptera novaeangliae) in Puerto Rican waters
Unusual aggressive behavior encountered by divers from Antillean manatees (Trichechus manatus manatus) in Puerto Rico
No full textThe reaction of a manatee mating herd to the presence of two SCUBA divers in Puerto Rico is presented