Polistes dominula and P. fuscatus often nest in bird nest boxes. Potential competition between wasps and birds was studied by removing wasp nests from some boxes. No difference in nesting success of breeding birds was found between boxes with wasp nests and those in which wasp nests were removed. Boxes that never had a wasp nest and boxes from which wasp nests were removed differed greatly in bird occupancy, suggesting that birds detected previous wasp presence. Some bird species gain protection by nesting near wasp nests. Birds may prefer to nest near wasp species that inflict higher sting pain levels. A rank correlation of data from published studies provided no evidence that pain level influences which wasp nests are most attractive to nesting birds. A comprehensive table of bird-wasp nesting associations (listing 121 bird species, 28 wasp species and 4 bee species) is included here.

No description available.

Estrogen acts on maternal circuitry to establish maternal behaviour in otherwise non-maternal rats. The precise mechanisms by which estrogen primes maternal circuitry are unknown; however, the medial preoptic area (MPOA) stimulates maternal behaviour whilst the medial amygdala (MeA) inhibits it. This thesis aimed to address the link between estrogen sensitivity, astroglia and maternal behaviour. Maternal care influences maternal behaviour of female offspring. One mechanism underlying this influence is differential estrogen sensitivity within the MPOA. Estrogen receptor alpha (ERalpha) expression was examined in offspring of High and Low licking/grooming (LG) dams within the MPOA. Enhanced expression ERalpha was limited to the medial preoptic nucleus in offspring of High LG dams and the anteroventral periventricular nucleus in Low LG dams. Adult nulliparous offspring of High and Low LG dams were assessed for maternal responsiveness using the pup sensitization paradigm. Offspring of Highs showed maternal behaviour significantly earlier than offspring of Lows. Brains of pup-exposed and pup-naive High and Low offspring were analyzed for astroglial markers glial fibrillary acidic protein (GFAP) and glutamine synthetase. Pup-naive animals showed more GFAP positive cells within the posteroventral MeA, with no differences within the MPOA and no effect of maternal care. Glutamine synthetase, a glial-derived enzyme necessary for glutamate production, showed greater expression within the MeA of High LG pup-naive animals; with no maternal care differences observed in pup-experienced animals. Thus, long-lasting changes within maternal circuitry established in early life are reflected in regionally specific enhanced estrogen sensitivity and latency to display maternal behaviour, but the effects are less clear with respect to astroglia.

This research project gauges producer demand on the Canadian Prairies for the attributes of new hypothetical varieties of winter wheat. Data collected from a survey of producers in Western Canada is used to determine the values and attitudes of producers regarding new winter wheat variety traits with a focus on increased winter survival rates and increased waterfowl nesting habitat. Increased nesting habitat was found to have a small negative but significant impact on the decision to adopt hypothetical winter wheat varieties; however winter kill rates and gross profit had a large positive effect on its adoption and expansion. Other important drivers of the decision to adopt hypothetical winter wheat varieties are also analyzed. Policy implications include potential guidance of incentives for environmentally friendly farming practices, and the provision of information to winter wheat breeding programs about the needs of producers.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2004. / Härtill 5 uppsatser.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2007. / Härtill 7 uppsatser.

Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Jay J. Rotella. Includes bibliographical references.

Made available in DSpace on 2015-04-17T14:55:16Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1302187 bytes, checksum: c5e711d7d5aae70cd68adbb071c9becf (MD5) Previous issue date: 2011-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Terrestrial ecosystems, solitary bees and wasps play important roles as pollinators, predators and parasites. Most part of the life of these Hymenoptera is designed to aspects related to nesting, including the search of the nest site, nest construction and food collection to rear the larvae. However, in natural environments the nests of these insects are difficult to find. A solution to this problem, at least for some species, is the use of artificial burrows in the field (trap nests). Using trap nests it is possible to collect standardized samples and to study the biology of some species. Thus, the community of solitary bees and wasps, nesting in trap nests was evaluated using parameters such as richness, diversity and nest abundance in two different agroecosystems of the state of Pernambuco, northeastern Brazil: sugarcane monoculture and polyculture. Moreover, the natural history and nesting biology of a bee species (Megachile dentipes) collected in the trap nests was studied. In this study, the main aspects of life history (seasonality, diameter of the nests, sex ratio, parasitism, development time) and nesting biology (nest architecture, nesting behavior, larval diet) was studied. Insects were sampled using the technique of trap nests, which consisted of 1) cardboard tubes inserted into blocks of wood of different diameters (4, 6, 8 and 10 mm), and 2) wooden planks, drilled lengthwise (5, 6, 8, 10 and 12 mm in diameter) and covered with a transparent plastic sheet (observation-nests). In each agroecosystem 3.360 cardboard tubes were available for nesting during one year (June/2009 to May/2010) and 1000 holes of observationnests during five months (October/2009 to February/2010). In the monoculture a total of 259 nests, 86 (33.2%) build by bees and 173 (66.8%) by wasps were sampled. Five species of bees were sampled, and Megachile dentipes was the most abundant bee species in the sugarcane (n = 76; 85%). In the polyculture area, 411 nests were collected, being 254 (61.8%) of bees and 157 (38.2%) of wasps. In this environment, 14 spp. nesting bee species were recorded. The leaf-cutter bee Megachile dentipes was also the most abundant (n = 117 nests, 46%). The abundance of bee nests, species richness and diversity of bees and wasps was significantly higher in the polyculture area compared to monoculture area. It is suggested that plant richness is a determining factor in the occurrence of the species. However, other factors such as distance from forest fragments and the use of herbicides and burning, might have influence in the low richness and diversity of bees and wasps in the area with sugarcane monoculture. Regarding Megachile dentipes it was shown that it is an polilectic species, collecting pollen from a wide spectrum pollen from mainly five botanical families: Asteraceae, Rubiaceae, Euphorbiaceae, Mimosaceae and Scrophulariaceae. This species showed a clear preference for nesting in the dry periods of the year in both studied areas, with peaks in October and December. Furthermore, this species had several generations throughout the year (multivoltine). It was demonstrated experimentally that recognition of the cavities by females is determined by the nest position in the blocks. Probably, chemical signals (marking the cavity) are not used, at least in the initial recognition of the nests. Nest structure of M. dentipes differs from most species because the lining of the brood cell is made from chewed leaves unlike the other species that involve the brood cells with whole leaves not chewed.. Biological and ecological characteristics of M. dentipes, as e.g. abundance and poliletia, makes this species a good candidate for management programs aimed at pollination, but further studies are necessary for that purpose. / Nos ecossistemas terrestres, abelhas e vespas solitárias desempenham essenciais papéis como polinizadores, predadores e parasitas. Grande parte da vida das fêmeas desses himenopteros é destinada à nidificação, como busca pelo local do ninho, construção do ninho e coleta do alimento larval. Contudo, os ninhos desses insetos em ambientes naturais são difíceis de serem encontrados. Uma solução para este problema, pelo menos para algumas espécies, é a utilização de cavidades artificiais no campo (ninhosarmadilha), uma vez que amostragens dos ninhos podem ser realizadas de forma padronizada em diferentes ambientes, além de fornecerem dados acerca da biologia das espécies capturadas. Diante disso, a comunidade de abelhas e vespas solitárias nidificantes em ninhos armadilha foi avaliada a partir de parâmetros como riqueza, diversidade e abundância de ninhos em dois agroecossistemas em Pernambuco: monocultura canavieira e sistema de policultura. Além disso, foi estudada a história natural e biologia de nidificação da espécie de abelha (Megachile dentipes) mais abundante nos ninhos-armadilha. Neste estudo foram avaliados os principais aspectos relacionados à história de vida (sazonalidade, razão sexual, parasitismo, tempo de desenvolvimento) e biologia de nidificação (arquitetura do ninho, comportamento de nidificação, dieta larval) de M. dentipes. Os insetos foram amostrados através da técnica de ninhos-armadilha, que consistiu de 1) tubos de cartolina inseridos em blocos de madeira de diferentes diâmetros (4, 6, 8 e 10 mm), e 2) pranchas de madeira, perfuradas longitudinalmente (5, 6, 8, 10 e 12 mm de diâmetro), cobertas com uma lâmina plástica transparente (ninhos-observação). Em cada agroecossistema estudado, foram disponibilizados para nidificação 3.360 tubos de cartolina ao longo de um ano (junho/2009 a maio/2010), e 1.000 cavidades de ninhos-observação durante cinco meses (outubro/2009 a fevereiro/2010). Um total de 259 ninhos, sendo 86 (33,2%) de abelhas e 173 (66,8%) de vespas foi coletado nas armadilhas instaladas na monocultura. Foram amostradas 5 espécies de abelhas, dentre elas, Megachile dentipes, a espécie de abelha mais abundante no canavial (n=76; 85%). Na área com policultura, foram coletados 411 ninhos, sendo 254 (61,8%) de abelhas e 157 (38,2%) de vespas. Neste ambiente, foram registradas 14 spp. de abelhas nidificantes ninhos armadilha. Mais uma vez, a espécie de abelha corta folha Megachile dentipes foi a mais abundante em número de ninhos (n=117; 46%). A abundância de ninhos de abelhas e a riqueza e diversidade de espécies de abelhas e vespas nidificantes em ninhos-armadilha foi significativamente maior em área de policultura quando comparada à monocultura canavieira. É sugerido que a riqueza florística de cada área seja um fator determinante na ocorrência das espécies. Contudo, fatores como a distância de fragmentos de mata e a utilização de herbicidas e queimadas, podem ter colaborado para uma baixa riqueza e diversidade de abelhas e vespas na área com monocultura canavieira. Quanto à espécie Megachile dentipes, observou-se que trata-se de uma espécie polilética, que coleta pólen de um amplo espectro polínico envolvendo, principalmente, cinco famílias botânicas: Asteraceae, Rubiaceae, Euphorbiaceae, Mimosaceae e Scrophulariaceae. Esta espécie mostrou uma clara preferência em fundar ninhos nos períodos mais secos do ano, em ambas as áreas estudadas, com picos de nidificação em outubro e dezembro. Além disso, apresentou várias gerações ao longo do ano (multivoltina). Foi demonstrado experimentalmente que o reconhecimento das cavidades pelas fêmeas baseia-se na posição em que o orifício se encontra no bloco de ninhos-armadilha. Provavelmente, não estão envolvidos sinais químicos (marcação da cavidade) ao menos no reconhecimento inicial dos ninhos. A estrutura do ninho de M. dentipes difere da maioria das espécies descritas até o momento, pois o revestimento da célula de cria é feito com folhas trituradas (manipuladas), diferentemente das demais espécies que envolvem as células de cria com folhas inteiras não trituradas. Características biológicas e ecológicas de M. dentipes, como e.g. abundância e polilectia, tornam esta espécie uma boa candidata a programas de manejo visando a polinização, embora sejam necessários mais estudos direcionados a essa finalidade.

Climate change poses a serious threat to species that demonstrate temperature dependent sex determination (TDS), including marine turtles. Increased temperatures can result in highly female skewed sex ratios and decreased hatchling success. In situ sand temperature data was collected from the nesting depth of hawksbill and green turtles at five study sites along the coast of the Red Sea. The sand temperature profile at four of the sites exceeded the pivotal temperature of 29.2°C (commonly cited in literature) throughout the study duration, which suggests feminization of turtles could be occurring, but further studies need to identify the pivotal temperature in this region. The percentage of days exceeding the commonly cited maximum thermal threshold (33 and 35°C) was calculated for each site at 30 and 50 cm. Sand temperature recordings were as high as 36.0°C at 30 cm depth, and 35.3°C at 50 cm. This suggests that the turtle hatchlings in some areas of the Red Sea could already have high mortality rates due to high temperatures, unless they are locally adapted to these high temperatures. The Red Sea is home to five out of the seven extant species of marine turtles in the world, but not much is known about these populations. The Red Sea is an understudied region of the world, but it has the potential to provide insight on how species might adapt to future climate change due to its high and variable water temperatures (range of 20°C to 35°C) and high salinity (40 PSU). Sites with lower sand temperatures (and lower risk of feminization) may represent priority areas for conservation efforts, particularly in regions facing imminent coastal development.

The aim of this work was to study the occurrence, abundance and distribution of breeding population of model species Reed Warbler (Acrocephalus scirpaceus) at selected locations. Subsequent evaluation is based on the monitored nesting parameters: nest height above water surface, water depth, distance of the nest from unvegetated water surface, the distance of the nest from the nearest fixed point, and number of stalks on which the nest was built. Diet spectrum was also detected. The results were statistically analysed in order to find out if and how these factors could influence nesting success and density of Reed Warbler population. Marginal influence on nesting success was found out only in these parameters: the number of stalks (the nests with three stalks was the most successful) and the distance from the fixed point. Successful nests were about 26% further (1.8 m) than the unsuccessful nests that could be explained by the predator factor. The most numerous insect orders in selected locations were Diptera (60%), Hymenoptera (21%) and Araneae (12%).