Male-male Competition and Reproductive Success in Elephant Seals

  title={Male-male Competition and Reproductive Success in Elephant Seals},
  author={Burney J. Le Boeuf},
  journal={Integrative and Comparative Biology},
  • B. L. Boeuf
  • Published 1974
  • Biology
  • Integrative and Comparative Biology
Male-male competition and reproductive success of northern elephant seals, Mirounga augustirostris , was studied for six consecutive breeding seasons at Ano Nuevo Island, California. The conclusions were as follows: (i) Less than one third of the males in residence copulate during a breeding season. A few males are responsible for the majority of copulations, (ii) The number and age of males copulating varies with: (a) harem location and topography, (b) the number of estrous females in the… Expand
The cost of success: reproductive effort in male southern elephant seals (Mirounga leonina)
It is shown that total reproductive effort increases with age, with no sign of late decrease or senescence, in southern elephant seals, the most dimorphic and polygynous of all mammal species. Expand
Parental investment and the secondary sex ratio in northern elephant seals
Data on northern elephant seals bearing on sex ratio theory suggest that parents invest equally in sons and daughters when investment is measured in terms of future reproduction and provide no support for the theory of adaptive shifts in sex ratio. Expand
Sexual Behavior of Male Northern Elephant Seals: I. Lethal Injuries To Adult Females
Based on the observed incidence of female mortality in relation to females present on the rookery, the probability of a female being killed by a male during the breeding season is about one in a thousand; females are expected to evolve adaptations to reduce injurious encounters with males. Expand
Female competition and reproductive success in northern elephant seals
The probability of weaning a healthy pup increases with age in female northern elephant seals, Mirounga angustirostris. On Ano Nuevo Island, California, weaning success among ‘prime’ females, those 6Expand
Social effects of space availability on the breeding behaviour of elephant seals in Patagonia
Low-density breeding conditions benefited female reproductive success through an increase in pup survival and limited the potential for polygyny in this Patagonian breeding colony of southern elephant seals. Expand
Reproductive Behaviour of Southern Sea Lions
Differences in behaviour between Otaria and males of other sea lion species are evident in harem size, time away from females, the high percentage of males breeding, and the low variance in mating success among breeding males. Expand
Female strategies of harassment reduction in southern elephant seals
Protests had a role in disruption of mating attempts, although the phenotype of interactors was more important: adult, large and dominant males disrupted interactions regardless of incitation by female protest. Expand
Mate guarding, reproductive success and female choice in African elephants
Male guarding of females, male mating success and female choice were studied for 8 years among a population of African elephants and the behaviour of oestrous females resulted in their mating with males who were old, vigorous and healthy. Expand
Effects of body size and harem size on male reproductive behaviour in the southern elephant seal
The rate of alert behaviour and time devoted to resting were not correlated with harem size for any of the three male categories, but rate of agonistic behaviour increased with increasing haremSize for central males, and the mating success of central males over the season increased with haree size. Expand
Male Competition, Mating Success and Female Choice in a Seasonally Breeding Primate (Erythrocebus patas)
It is found that patas monkeys with restricted breeding seasons show a fluid number of males in groups, with the same groups able to shift rapidly from single to multimale structure, and aggressive success was not significantly correlated with copulation rate for males in the multimale group. Expand


Sexual behavior in the Northern Elephant seal Mirounga angustirostris.
The mating behavior of Northern elephant seals was studied during the I968, I969 and I970 breeding seasons at Ano Nuevo Island, I9 miles north of Santa Cruz, California and the greatest difference in the copulatory pattern of the elephant seal, a true seal, and members of the sea lion family is that the former interfere with the copulations of other males while the latter do not. Expand
Perinatal behavior of northern elephant seal females and their young.
Northern elephant seal females and pups were observed during four breeding seasons at Ano Nuevo Tstand, California and the probability of separation was increased by high numbers of females and disturbances created by intrusions of breeding hulls into the harem. Expand
Elephant seals on the Farallones: population structure of an incipient breeding colony.
The colonization of Southeast Farallon Island, California, by northern elephant seals, Mirounga angustirostris , began in 1959 with the appearance of a single animal. By 1971, over 100 juveniles wereExpand
Booming territory size and mating success of the greater prairie chicken (Tympanuchus cupido pinnatus).
  • R. Robel
  • Biology, Medicine
  • Animal behaviour
  • 1966
The size of the inner portion of the territory and the total territory size appear to be directly related to mating success in booming populations of greater prairie chickens. Expand
Social Status and Mating Activity in Elephant Seals
Individually marked male elephant seals, Mirounga angustirostris, observed on an island off central California participate in a social hierarchy resembling the peck order of domestic chickens, the higher the status of a male, the more readily he approaches and copulates with females. Expand
Dialects in Elephant Seals
Threat vocalizations of male elephant seals Mirounga angustirostris vary among four populations on islands off the coast of California and Baja California, Mexico. Males at San Nicolas Island inExpand
Seals and Group Selection
Seals have been shown to restrict recruitment in crowded populations because of gregarious and hierarchical behavior. Some authors have suggested that such behavior has evolved through groupExpand
  • G. Bartholomew
  • Biology, Medicine
  • Evolution; international journal of organic evolution
  • 1970
The present paper undertakes to elaborate a verbal model based on ideas first suggested by Nutting (1891) and extended by Bertram (1940) and by Bartholomew (1952) and to place it more firmly in a documentable behavioral context. Expand
The Descent of Man, and Selection in Relation to Sex
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Parental investment and sexual selection
Charles Darwin's (1871) treatnent of the topic of sexual selection was sometinrcs confused because he lackcd a gcneral framework within which to relate the variables he perceived to bc important:Expand