Browsing by Author "LIMA, M"

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    A CASE OF PARASITE-MEDIATED COMPETITION - PHENOTYPIC DIFFERENTIATION AMONG HOOKWORMS UNCINARIA SP (NEMATODA, ANCYLOSTOMATIDAE) IN SYMPATRIC AND ALLOPATRIC POPULATIONS OF SOUTH-AMERICAN SEA LIONS OTARIA-BYRONIA, AND FUR SEALS ARCTOCEPHALUS-AUSTRALIS (CARNIVORA, OTARIIDAE)
    (1992) GEORGENASCIMENTO, M; LIMA, M; ORTIZ, E
    Hookworms in otariids are considered to meet the conditions and to fulfill the predictions set forth in the theoretical literature to define a likely case of host coexistence mediation by a shared pathogen. The intensity of infections, the prevalence of skin lesions and the morphometry of hookworms Uncinaria spp. were examined in South American sea lions and fur seals sampled along the Chilean and the Uruguayan coasts in spring and summer 1981 to 1991. In sympatric host populations from Uruguay, there were clear differences in intensity of infections, prevalence of skin lesions, and body size of the hookworms from the two host species. Sea lions from Chile, allopatric to fur seal populations, are less intensively infected and hookworms found in these sea lions have the smallest body size reported in otariids, while those from South American fur seals are the largest. Hookworms found in sea lion pups from populations sympatric to fur seals revealed intermediate values in intensity and in body size, and the sea lion pups had the highest prevalence of skin lesions. Other reports of hookworms in otariids show intermediate morphometry, following a general linear trend of differentiation in size. Consequently, they are considered to belong to the same, widely distributed species Uncinaria lucasi Stiles, 1901.
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    GROWTH AND REPRODUCTIVE PATTERNS IN THE SOUTH-AMERICAN FUR-SEAL
    (1995) LIMA, M; PAEZ, E
    We describe patterns of age-specific growth and reproductive rates for female South American fur seals, Arctocephalus australis, in Uruguay. Females achieve body weight of 41.7 kg at 10 years of age and adult length of 128.9 cm at 10 years of age. Pregnancy rates showed significant interannual differences, suggesting effects from environmental factors and demographic variability. Fetuses from lactating females were smaller than fetuses from nonlactating females. We suggest that simultaneous lactation and pregnancy affect the amount of energy devoted to embryonic growth.