Latin American Journal of Aquatic Mammals (LAJAM)
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Surface observation of a birth of a humpback whale (Megaptera novaeangliae) on the northeast coast of Brazil
No full textDistribution and conservation status of the Antillean manatee (Trichechus manatus manatus) in Honduras
No full textThe Antillean manatee, Trichechus manatus manatus, is among the most threatened mammals in Honduras, yet the last published study is from 1980. Since then, the North Coast of Honduras has experienced rapid population growth and land cover change possibly causing habitat loss for manatees. We conducted aerial, boat, and interview surveys between 2005-2007 along the northern and remote eastern coasts of Honduras to assess the current status and distribution of manatees. In addition, we compiled all available data on manatee mortality from museum specimens, unpublished reports, and interviews to determine current threats. We averaged 1.2 manatee sightings per survey hour during six flights along the North Coast in March-April 2006 during 14.4 aerial survey hours. Sightings were mainly clustered in Cuero y Salado Wildlife Refuge (CSWR) and Rios Chapagua and Aguan, which we indentify as important conservation areas. Our total and average sightings per survey hour in CSWR were much lower than those reported in 1979-80, in spite of the area being protected since 1987. Our interviews indicate that manatees are still present on the eastern coast (La Mosquitia), however we observed none during 14.5 survey hours in June 2005 and April 2007. The major cause of known mortality from 1970-2007, based on 26 records, was due to entanglement in fishnets. Despite local and federal protection, manatees are still poached and opportunistically caught in fishnets. While some efforts have been made by local NGOs to raise public awareness for manatees, a national conservation program is highly recommended to centralize and coordinate efforts
Return to the wild and reintegration of a giant river otter (Pteronura brasiliensis) cub to its family group in Amanã Sustainable Development Reserve, Brazilian Amazon
No full textAtypical records of pinniped specimens housed in the Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’
No full textThe recurring visit of a southern elephant seal (Mirounga leonina L. 1758) to the coast of Antofagasta, northern Chile
No full textA review of marine mammal records of Cuba
No full textThere has been very little research on marine mammals in Cuban waters. Much of the information on marine mammals in this region is buried in historical and gray literature. In order to provide a comprehensive account of marine mammal occurrence in Cuba’s Exclusive Economic Zone (EEZ), we reviewed and verified 659 published and unpublished sighting, stranding, capture, and tagging records. Eighteen extant species and four genera have confirmed records for Cuban EEZ waters. This includes 17 species of cetaceans (three baleen whales and 14 toothed whales) and one sirenian species. An additional 11 cetacean species and one extant pinniped species have been reported, but not confirmed, or may have the potential to occur in Cuban waters. Historical records of the Caribbean monk seal (Monachus tropicalis) are documented in Cuba; however, this species is now considered extinct. The only two species that are seen regularly and considered common in Cuban nearshore waters are the common bottlenose dolphin (Tursiops truncatus) and the West Indian manatee (Trichechus manatus)
On the stomach contents of a Risso’s dolphin (Grampus griseus) from Chile, Southeast Pacific
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Sperm whales of the Southeast Pacific. Part VII. Reproduction and growth in the female
No full textThis report on the reproduction and growth of the female sperm whale Physeter catodon is Part VII of our work on this whale in the Southeast Pacific. There were 1105 female sperm whales in our sample collected from two whaling stations in Chile and two in Peru. Since Clarke and Paliza (1972) have shown that they belonged to a single stock, we have worked them together. A second Graafian follicle develops more than the others in each ovary so to improve the possibility of fertilization in case the first ovum fails to be impregnated. We consider the size of the Graafian follicle at, or near, ovulation to be around 100mm, larger than what has been found in sperm whales from other seas. The corpus luteum of pregnancy is significantly larger than the corpus luteum of ovulation. The corpus albicans reduces in size throughout the life of the whale and probably does not disappear. There is a highly significant correlation between the total number of corpora and age: therefore we use the number of corpora as an indication of age. The corpora atretica are more frequent in older female sperm whales reflecting less fertility in this group. The sexual cycle in sperm whales of the Southeast Pacific has been revised to last 4yrs. Sexual maturity in female sperm whales is attained at 8.2m long and 6.5yrs of age, being both values lower than in sperm whales from other seas. The female sperm whale is born at 3.90m. The incidence of twins, 0.91%, is higher than in other seas. Fertility is low in very young whales (1-2 ovarian corpora) and it is at its lowest in the older group (over 12 corpora). The highest fertility is when females have 3-10 ovarian corpora and they are 15 to 35yrs old. The proportion of active females in pre oestrus during the months of pairing is significantly higher than during the other months. Accessory ovulations during oestrus are represented by the small groups of lactating-and-recently ovulated and lactating-and-pregnant whales. Unsuccessful ovulations are more frequent in late lactation and late resting periods, being post-partum ovulation rare. Female sperm whales in the Southeast Pacific may ovulate up to four and possibly five times during an oestrus. Physical maturity is attained at 11.2m long and 33.5yrs old. Fusion of the vertebrae begins at both ends of the vertebral column and finishes between the posterior thoracic and the lumbar vertebrae. Female sperm whales of the Southeast Pacific may live, at least, up to 50yrs of age. The age at recruitment between 1959 and 1962 was 20-21yrs of age when they had accumulated 4–5 corpora in their ovaries
Dr. Robert Henry Clarke, Oceanographer, M.A. (Oxon), Dr. Philos. (Oslo), 1919-2011
No full textIn Memoriam for Dr. Robert Clarke, 1919-201