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Whooping Cranes (Grus americana) are a long-lived, monogamous avian species, yet little documentation of copulatory behavior and timing in relation to egg-laying has occurred in wild populations. We monitored 10 crane pairs in Florida before and during the 2010 breeding season to document copulation timing and pre- and post-copulatory behavior. Monitoring began 111 days before incubation initiation for the first nest of the season. Pairs were observed for 124.62 hrs ([bar.x] = 76.30 min, range = 14-375 min) during 98 observation periods: 17 observation periods occurred on days with precipitation. Three copulations were observed, two by one established pair and another by unpaired individuals. The copulations by the established pair occurred 9 and 18 days before incubation began. The third was an extra-pair copulation, which occurred between a paired female and a lone male, the first documented for the species. No copulations were observed on days with precipitation. We examined flock monitoring accounts from 1999 through 2009 in this non-migratory population; 21 observations of copulations revealed Whooping Cranes copulated up to 62 days before incubation began and between 0510-1345 hrs EST. Our data suggest copulation occurs between early morning and early afternoon and does not appear to be associated with precipitation. Key words: copulation, extra-pair copulation, Florida, Grus americana, precipitation, rainfall, Whooping Cranes., The Whooping Crane (Grus americana) laced extinction as recently as the 1940s, when its numbers decreased to ~21 individuals (Canadian Wildlife Service and U.S. Fish and Wildlife Service 2007). The [...]

Saltmarsh Sparrows (Ammodramus caudacutus) are non-territorial, lack pair-bonds, and practice promiscuous mating behavior and obligate maternal care of young. Behavioral details of mating behavior and associated intermale aggressive behavior are poorly understood in the species. We report the results of an observational study of mating and agonistic behavior of individually marked breeding birds in New York. We witnessed 1,265 sexual and agonistic interactions within and among males and females from 1977 through 1985. We found no evidence of male mating aggregations, and male aggressive behavior was prevalent only in male-initiated sexual interactions. Females solicit matings from males during nest-building, but the behavior is inconspicuous and not associated with male aggression. Males spend the morning patrolling their home ranges, and chase or approach females they encounter anywhere in their breeding habitat. Males often concentrate patrol activity in the vicinity of nests under construction, but we found little evidence they know the location of most nest sites. Some males seek to forcibly mount females on the ground at any breeding stage, despite female resistance. Females thwart forced mountings in 57% of cases either by fighting with the males, or by uttering an aggressive call. When a more persistent male suppresses a female's resistance, she then crouches passively as he assumes a copulatory position on her back. We discuss this behavior in terms of female control of forced mountings, female choice of mates, and forced mating as a tactic of males that appear not to know the fertility status of females. Males have a large cloacal protuberance, which suggests sperm competition is strongly developed in the species. We caution that evolution of the unusual mating behavior in Saltmarsh Sparrows must be understood in relation to the different sexual behaviors of its closest relatives. Received 11 April 2011. Accepted 18 January 2012., Historically, behavioral ecologists interested in evolution of mating systems in birds often focused their attention on species that practice unusual, minority forms of mating behavior. Various expressions of social monogamy [...]

Few descriptions exist of the nesting behavior of the Gray Trembler (Cinclocerthia gutturalis), and the only nest description of this species seems incongruent with what is known about nesting behavior of other species of Mimidae. We report the first definitively described nest of the Gray Trembler in St. Lucia, West Indies in June-July 2007. We observed construction of, incubation at, and feeding of nestlings in an open-cup nest, similar in architecture to nests of other mimids, contradicting previous reports that Gray Trembler nests are domed, constructed of dried grass, and on top of palm (Cocos nucifera) trees. Received 18 May 2010. Accepted 27 October 2010., Nesting biology is a basic component of the natural history of passerine birds. Nest structure can reflect phylogenetic relationships (Hansell 2000) and, along with nest-site selection, influence the likelihood of [...]

We present evidence of cooperative breeding in Society Kingfishers (Todiramphus veneratus). Groups of three kingfishers were observed cooperatively excavating nest cavities, incubating, and provisioning young. Three bird groups also comprised half of visual observations recorded during island-wide point transect surveys that occurred during the onset of breeding. Society Kingfisher densities were an order of magnitude greater than other Pacific kingfisher populations, which may lead to resource saturation and evolution of cooperation in this species. Our results lend insight into cooperative behaviors and facilitate conservation of birds in French Polynesia., Cooperative breeding has been a focus of behavioral ecologists and evolutionary biologists for decades (Skutch 1935, Brown 1987, Stacey and Koenig 1990, Koenig and Dickinson 2004). Broadly defined, cooperation occurs [...]

Chimpanzees (Pan troglodytes) and rhesus macaques (Macaca mulatta) selected either Arabic numerals or colored squares on a computer monitor in a learned sequence. On shift trials, the locations of 2 stimuli were interchanged at some point. More errors were made when this interchange occurred for the next 2 stimuli to be selected than when the interchange was for stimuli later in the sequence. On mask trials, all remaining stimuli were occluded after the 1st selection. Performance exceeded chance levels for only 1 selection after these masks were applied. There was no difference in performance for either stimulus type (numerals or colors). The data indicated that the animals planned only the next selection during these computerized tasks as opposed to planning the entire response sequence.