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Hurricanes are major disturbance events in Neotropical mangrove communities, potentially affecting the reproductive success of mangrove species. This was the first investigation of changes in mangrove pollinator assemblages following hurricanes, and the effect of these changes on the mating system of Laguncularia racemosa. Insect pollinator assemblages were investigated in three Florida mangrove communities in 2001–2003, 2005 and 2009; two hurricanes affected the area in 2004. Visitation rates were estimated from 1445 insects observed during 272 10-min intervals; the number of flowers visited by each insect was also recorded. Pollinator diversity was estimated with the Shannon Index. Following the hurricanes, species richness was reduced by 43–65% and diversity declined by 36–70%. Significant declines in insect visitation to L. racemosa resulted in reduced outcrossing frequencies in 2005. Laguncularia racemosa flowers autogamously self-pollinate without insect visitors, so fruit set still occurred. Visitation rates returned to pre-hurricane levels by 2009, but foraging behaviours differed from pre-hurricane patterns; outcrossing was further favoured by reduced frequencies of long foraging bouts and increased frequencies of short foraging bouts. The mixed mating system of L. racemosa provides reproductive assurance following hurricane disturbances, when pollinator abundance is low.

Mathematical models predict that to maintain androdioecious populations, males must have at least twice the fitness of male function in hermaphrodites. To understand how androdioecy is maintained in Laguncularia racemosa (white mangrove), outcrossing, inbreeding depression, and relative male fitness were estimated in two androdioecious populations and one hermaphroditic population. Outcrossing was estimated based on length of pollinator foraging bout and pollen carryover assumptions. Inbreeding depression was measured at three life stages: fruit set, seedling emergence, and seedling survivorship. The relative fitnesses of males and the male component of hermaphrodites were compared at these three stages and at the pollen production stage. Male frequency predictions generated by Lloyd's model were compared with observed frequencies in two androdioecious subpopulations. Outcrossing estimates were moderate for all populations (0.29-0.66). Inbreeding depression varied among populations (-0.03-0.86), but the strength of inbreeding depression did not increase with male frequency. Males produced significantly more flowers/inflorescence than hermaphrodites, but pollen production/flower did not differ. Male and hermaphroditic progeny did not differ significantly at other life stages. Populations of white mangrove with male plants were functionally androdioecious. Lloyd's model accurately predicted male frequency in one androdioecious subpopulation, but underestimated male frequency in the second subpopulation.

Insect-pollinated Laguncularia racemosa has a variable breeding system; some populations are androdioecious, with male and hermaphroditic plants, while others lack male plants. We observed the foraging behaviours of insects in three androdioecious and three hermaphrodite-only populations of L. racemosa in Florida. In each population, insect visitation rates were estimated from 30–108 timed intervals. We recorded the number of flowers visited by 144–224 insects during foraging bouts made to 15–40 male and hermaphroditic plants. Male plants in androdioecious populations had significantly more visitors than hermaphroditic plants, increasing the number of vectors carrying pollen from male plants. Further, many insects visited few flowers during foraging bouts, which should increase outcrossing frequency. According to mathematical models, male plants benefit from these combined factors. Plants in hermaphrodite-only populations had significantly more visitors than hermaphroditic plants in androdioecious populations. Proportionately more insects visited many flowers during foraging bouts in hermaphrodite-only versus androdioecious populations. The increased likelihood of geitonogamous self-pollination could help explain the lack of male plants in hermaphrodite-only populations. Differences in pollinator assemblages and the relative abundances of several species were responsible for differences in foraging behaviours: Apis mellifera, Bombus sp., Melissodes sp., Xylocopa sp., Euodynerus sp. and a calliphorid species.

This is the first study of the nesting ecology of Megachile (Pseudocentron) alleni, a common ground-nesting solitary bee found throughout the Bahamas. While apparently an important pollinator in coastal communities, very little is known about its nesting behavior. Previously, we observed females collecting three plant resources: nectar, pollen, and leaves. We hypothesized which plants would be used for nectar and which for pollen based on the architecture of the floral display and observations of insect behavior. To test these hypotheses, we isolated and identified pollen occurring in cocoons from nest cells. We observed 412 interactions between M. alleni individuals and the flowers of 26 plant species in 14 families. Fifteen pollen species were identified from 15 dissected cocoons; cells averaged 5.5 pollen species ±1.7 SD. Two-thirds of the cocoons contained pollen from three species (Corchorus hirsutus, Jacquemontia cayensis, and Lantana involucrata), and more than half of the pollen species were found in at least twenty-seven percent of the cells. We found pollen from eight of the hypothesized sources, but also pollen from four species hypothesized to provide only nectar, and from three species not previously recognized as floral resources. Leaves of at least four species were used for nest cell construction. Females searching for suitable nests flew over the ground, often searching in cavities under rocks or asphalt. Substrate under 52 nests was usually light sand (78%) or darker sand with humus (16%). Nests averaged 2.88 cells ±2.0 SD (N  =  37). Actively nesting females made numerous provisioning trips daily, each preceded by a brief orientation flight. One female was observed carrying leaf pieces, and later pollen, into her nest. On average, she spent 50% more time in the nest and 150% more time away from the nest while handling pollen. We observed one species of beefly parasitizing the nests.

The breeding system of Laguncularia racemosa is variable among populations; some populations are androdioecious while other populations lack male plants. To determine whether androdioecy is widespread in L. racemosa, 65 populations were surveyed in Florida and the Bahamas. Fruits are water-dispersed, so the observed distribution of breeding systems was compared to local and regional water currents in order to determine whether dispersal could be important to the maintenance of male plants in androdioecious populations. Twenty-two of the 36 populations surveyed in Florida were androdioecious, with male frequencies that ranged from 1–68%. On the Florida east coast, all populations north of latitude 26°30′ N lacked males while all populations south of this latitude were androdioecious, which suggests that northern populations may lack males due to dispersal limitation. The pattern of distribution on the Florida west coast suggests that males may be maintained in some populations via dispersal. Nine islands in north-central Bahamas were surveyed, and androdioecious populations were found only on San Salvador Island, where male frequencies ranged from 5–28%. Dispersal, fragmentation, and selection hypotheses are suggested to explain the observed pattern of distribution; these hypotheses will be tested in future studies.

Vingt spécialistes en éducation, en sociologie, en psychologie, en administration, en pédagogie et en andragogie font le point sur les orientations et les diverses formes de collaboration entre les institutions de formation et les milieux socioprofessionnels. Les auteurs expliquent comment a émergé le phénomène du partenariat entre les écoles et les entreprises, puis décrivent quelques expériences sous l'angle des milieux de l'éducation et du travail; enfin, ils posent un regard critique sur ce nouveau paradigme, exposent les principaux enjeux et proposent un modèle d'analyse du partenariat.

Nonprofit agencies rely on continued support from volunteers, many who are 65 years of age or older, to provide aid and services to local community. However, community nonprofits have experienced a recent decline in volunteerism over the last six years. With the number of adults age 65 and over expected to double by 2060 in the United States, this twofold population could address the decline in volunteerism for nonprofit agencies. The purpose of this qualitative phenomenological research was to explore and identify factors that influence motivation, recruitment and retention of volunteers age 65 and over. The study aimed to enhance understanding of how these adults make decisions regarding volunteer work, how they learned of the opportunity, what inspired them to volunteer, and what makes them committed to a particular organization. The study was specific to the nonprofit sector, focusing on individuals who volunteer at a charitable, religious, or health care organization in Southern California. The Existence, Relatedness, and Growth Theory was utilized to explain volunteer motivation and retention. Data were collected from 24 participants, age 65 and over, who volunteered a minimum of 12 times in a one year period. The study consisted of semi-structured interviews that were audio recorded, transcribed, and analyzed for common themes. Major findings from the study included 5 major themes that can affect volunteer motivation, recruitment and retention in adults age 65 and over: (a) health benefits, (b) relatedness or connectedness, (c) meaning-purpose, (d) pro-social righteousness, and (e) personal involvement. Understanding these themes can provide considerable insight to volunteer mangers to help develop effective recruiting and retention strategies, designed specifically for the older-adult population, to increase volunteering in agencies throughout the United States.

A literature review on retention as it relates explicitly to women and people of color suggests that specific and unique factors play a part in student persistence. Despite the gains made in enrollment on college campuses, this group of students seems to have a particularly difficult time completing degree requirements. This article reflects on key variables that affect persistence in this group of students as well as institutional responses to the retention problem. Also, the need for curricular reform to address the experiences of minorities and women and the need for gender equity in the classroom are discussed.