In mixed stands of the annual Impatiens capensis and I. pallida, bumblebees visit I. pallida almost exclusively even when the nutritional reward of I. pallida is removed. This phenomenon contradicts certain models proposed for foraging behavior in simultaneously flowering species and those dealing with optimal foraging. Such foraging behavior could have potentially devastating effects on the nonpreferred species, especially if the plant is an annual. Both Impatiens species share the same primary pollinators when they grow allopatrically, but when they grow sympatrically I. pallida continues to attract bumblebees while I. capensis depends on hummingbirds and small bees for pollination. Thus competition for pollinators between these Impatiens represents an important plant-plant and plant·pollinator interaction with potential consequences. When I. capensis is less frequented by bumblebees when sympatric with I. pallida, I. capensis exhibits reduced fecundity. Mechanisms of interference through improper pollen transfer are described for the Impatiens species. Pollen of I. pallida adheres to and germinates on the stigmas of I. capensis and the pollen tubes reach the ovules. In contrast, pollen of I. capensis adheres poorly to I. pallida stigmas and fails to germinate. No hybridization occurs between the species. Scanning electron micrographs of pollen and stigma surfaces of the two species revealed no morphological differences. Among the floral characteristics examined, only flower color appeared to influence bumblebee preference for I. pallida. Differences between the species in ultraviolet absorbance patterns, perianth size and shape, odor, and nectar quantity and quality did not affect the pollinator preference of bumblebees. Differences in nectar characteristics and production rate were found among Impatiens populations. However, nectar quantity, quality, and production rates did not differ within allopatric or sympatric populations, but both species had higher nectar volumes with lower solute concentrations in the morning, and lower nectar volumes with higher solute concentrations in the late afternoon. Differences in nectar volumes among populations appeared to be associated with environmental factors affecting population sites. I. capensis avoids competition and maintains itself in sympatric populations with I. pallida by depending on hummingbirds and insects other than bumblebees as pollinators, and has the ability to produce cleistogamous flowers and their subsequent progeny to ensure sexual reproduction. However, inbred progeny of I. capensis are competitively inferior to outcrossed stock. Nevertheless, I. capensis does persist in mixed stands of I. pallida despite the absence of bumblebee pollination and the presence of lower seed set. / Ph. D. / incomplete_metadata

Traditional pollination syndromes group angiosperms into categories based on how floral traits impact the functional group of pollinator most associated with those traits. The concept, while well supported for specialist-pollinated plants, is a poor predictor of pollinator identity in generalist systems, such as those common to the family Asteraceae. One potential avenue for future refinement of the concept is the combination of large floral trait datasets, quantitative pollinator data, and phylogenetic comparative methods. Helianthus is a well-studied genus of North American aster whose species include the agriculturally significant H. annuus, which represents the third largest oilseed crop globally. The genus is primarily bee pollinated and, while much is known about traits that are correlated with bee attraction at short ranges common to agricultural and horticultural settings, there has been little research on long range visual and chemical attraction traits within the genus. Using data on display size and shape, ray color, floral volatile composition, and floret depth collected from Helianthus species grown in a common garden, mixed models were constructed to predict pollinator visitation as a function of floral traits. For four of seven pollinator response variables, there was at least one model that outperformed null models, and three of the four best models were multivariate. This work will inform future research of pollination syndromes within generalist systems such as those common to Asteraceae.

Thesis (MSc)--Stellenbosch University, 2010. / Thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Zoology at Stellenbosch University. / ENGLISH ABSTRACT: Most modern deciduous fruit cultivars are self-incompatible, and require polliniser trees to be planted in the orchard to provide the pollen necessary for cross-pollination, fertilization and fruit set. Polliniser trees are either non-commercial cultivars interspersed in the orchard solely to provide pollen, or crosscompatible cultivars inter-planted in the same orchard. 90% of the commercial crops dependent on bee pollination are courtesy of a single species, Apis mellifera. Both polliniser planting pattern and honey bee colony distance are known to influence crop production and crop quality, resulting in a rapid decrease in fruit weight, fruit set and seed number with increasing distance from the polliniser or honeybee colonies. However, the response of different crops and cultivars to polliniser and pollinator proximity on optimal crop yield is not known for deciduous fruit crops in the Western Cape, South Africa. The effect of polliniser position and honeybee colony distance on fruit set and weight was investigated in plums, apples and pears on the Lourensford Estate. The relationship between fruit set and fruit weight was investigated for deciduous fruit cultivars. In addition, fruit weight and seed number was also investigated in apples and pears. Fruit set tended to increase on sides of trees closer to the polliniser but not significantly so, except for apples. This suggests that there is probably better pollination closer to the pollinisers but this does not equate to increased yield. In fact, smaller fruit was produced on the sides of the trees closer to the polliniser for all orchards and significantly so for plum and for ‘Packham’s Triumph’ in Hillside 1. This negative relationship between fruit set and weight may indicate ‘over-set’ beyond the physiological limits of the trees. Fruits closer to the polliniser had significantly more seeds for both pear and apple cultivars indicating sufficient pollination. A significant relationship was found between the seed number in any particular fruit and the weight of the fruit in all the cultivars except ‘Packham’s Triumph’ where the relationship was negative, suggesting that ‘Packham’s Triumph’ set parthenocarpically. Colony distance had no effect on fruit weight, fruit set and on seed number indicating that colonies were adequately distributed and that there was no “pollination depression” in the centre of the orchards at Lourensford. In conclusion, the fact that we did not get a yield gradient with increased distance from the colonies suggested that the orchards at Lourensford Estate were sufficiently pollinated. / AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar

Thesis (PhD (Botany and Zoology))--Stellenbosch University, 2011. / ENGLISH ABSTRACT: With the current global decline in pollinators, and the concurrent decline in plant species, pollination research is becoming increasingly important. However, studies outside Europe and North-America and on groups other than insects are needed to make generalisations possible. In this thesis I study how pollination structures plant and bird communities in a biodiversity hotspot, the Cape Floristic Region of South Africa. I show that bird-plant pollination mutualisms are an important ecological factor structuring ornithophilous Proteaceae and nectar-feeding bird communities. This close association between plant and bird communities suggests an important role for community wide pollination mutualisms. How these mutualisms disassemble in reaction to a range of anthropogenic impacts is determined. Firstly, I use experimental manipulation of honeybee density to test whether honeybee farming affects nectar-feeding birds. Hive addition increased honeybee abundance far above natural levels but nectar-feeding bird pollinators were not consistently affected. Secondly, I document the impact of a two lane tar road on the bird pollination community. The two-fold decline found in pollination along roadsides, should have important implications for the way we view and manage road verges for ecological processes. Thirdly, I investigated how fragmentation affects bird-pollination communities by assessing an endangered, bird-pollinated plant, Brunsvigia litoralis. The only flower visitor at the urban sites, the shorter billed Greater Double-collared Sunbird is unable to access the nectar due to a long perianth tube. The longer billed Malachite Sunbird was the sole pollinator of B. litoralis at the rural site, significantly increased seed set. The lack of ecological analogs in these urban fragments might place pollinator specialist plants, such as B. litoralis, at risk. Fourthly, fire is a frequent disturbance in communities of bird-pollinated plants. In a before/after fire observation study and a burnt/unburnt transplant study, birds visited flowers in the “before fire” and “unburnt” areas only. The results are surprising given the large number of bird-pollinated plants flowering in the early post-fire vegetation. Lastly, I find that alien invasive plant species are incorporated into the native pollination community in a spectacular way; sunbirds adapt to a hummingbird-like, hovering lifestyle to obtain nectar. Alien invasive plants greatly increase nectar-feeding bird abundance; in turn, birds enhance seed set in these alien plants. I conclude by asking whether the disassembling of bird pollination communities really matters. To answer this question I report on a decade of demographic data on the geophytic bird-pollinated Brunsvigia orientalis. In the demographic analysis, the elasticity component for reproduction was more important than expected for a long lived plant. Reduced population growth in the shade and a large investment in a winged inflorescence, suggest B. orientalis is a light demanding, well dispersed, gap colonising species. The link between pollination and seed has been made before, but I take this one step further and show that pollination intensity predicts population growth rate. By linking plant demography and pollination, I was able to predict the future of plant populations under variable pollination conditions. The disassembly of bird pollination communities only becomes important for population persistence once the mutualism has almost entirely broken down. / AFRIKAANSE OPSOMMING: Met die huidige globale afname in bestuiwers en die gelyktydige afname in plant spesies, word bestuiwing navorsing toenemend belangrik. Studies buite Europa en Noord-Amerika en op groepe anders dan insekte is nodig on veralgemenings moontlik te maak. In hierdie tesis bestudeer ek hoe bestuiwing struktuur gee and plant en voël gemeenskappe in 'n biodiversiteit hotspot, die Kaapse Floristiese Ryk van Suid-Afrika. Ek wys dat voël-plant bestuiwings mutualismes 'n belangrike ekologiese faktor is in die strukturering van voël bestuifde Proteaceae gemeenskappe en nektar-etende voël gemeenskappe. Hierdie noue assosiasie tussen plant en voël gemeenskappe impliseer 'n belangrike rol vir gemeenskapwye bestuiwings meganismes. Ek bepaal hoe hierdie mutualismes aftakel in reaksie op 'n verskeidenheid van antropogeniese impakte. Eerstens gebruik ek 'n eksperimentele manipulasie van heuningby getalle om te toets of bye boerdery nektar-etende voëls affekteer. Byekorf toevoeging het heuningby getalle laat toeneem tot ver bo natuurlike vlakke maar nektar-etende voël bestuiwers is nie konsekwent beïnvloed nie. Tweedens dokumenteer ek die impakte van 'n twee baan teerpad op die voël bestuiwings gemeenskap. Die twee-malige afname in bestuiwing langs paaie sal belangrike implikasies hê vir die manier hoe ons pad reserwes sien en bestuur met betrekking tot ekologiese prosesse. Derdens bestudeer ek hoe fragmentasie die voël-plant gemeenskappe affekteer deur die bedreigde voël-bestuifde Brunsvigia litoralis te assesseer. Die enigste besoeker in die meer stedelike area, die Groot-rooibandsuikerbekkie, wat 'n korter snawel het, is nie in staat om die nektar te bereik nie, weens 'n te lang blombuis. Die Jangroentjie suikerbekkie met sy langer snawel is die enigste bestuiwer van B. litoralis in die meer landelike area, met 'n betekenisvolle vermeerdering in saad vorming. Die gebrek aan ekologies analogiese spesies in die stedelike fragmente kan 'n risiko inhou vir bestuiwer gespesialiseerde plante soos B. litoralis. Vierdens, vuur is 'n gereelde versteuring van voël-plant gemeenskappe. In 'n voor/na vuur observasie studie en 'n brand/nie-brand verplasing studie, het voëls blomme net in die “voor brand” en “nie-brand” areas besoek. Hierdie resultate is verrassend siende die groot hoeveelheid voël-bestuifde plante wat blom direk na brande. Laastens het ek gevind dat uitheemse indringer plante geïnkorporeer word in die inheemse bestuiwers gemeenskappe op 'n skouspelagtige manier; suikerbekkies pas aan tot 'n kolibri-tipe, fladderende lewenswyse om nektar te bekom. Uitheemse indringer plante het nektar-etende voël hoeveelhede laat toeneem; in reaksie het voëls saad opbrengs vermeerder. In konklusie vra ek of hierdie aftakeling van die voël bestuiwers gemeenskap belangrik is. Om hierdie vraag te antwoord assesseer ek 'n dekade van demografiese data van die geofietiese, voël-bestuifde plant, Brunsvigia orientalis. In die demografiese analises was die elastisiteit komponent van reproduksie belangriker as verwag vir 'n langlewende plant. Verminderde populasie groei in die skaduwee en 'n hoë investering in 'n gevlerkte bloeiwyse suggereer dat B. orientalis 'n lig afhanklike, goed verspreide, gaping koloniserende spesie is. Die skakel tussen bestuiwing en saadvorming is voorheen gemaak, maar ek neem dit een stap verder en wys dat bestuiwings intensiteit populasie groeikoers voorspel. Deur plant demografie en bestuiwing te koppel was ek in staat om die toekoms van populasies onder variërende bestuiwings kondisies te voorspel. Die aftakeling van voël bestuiwings gemeenskappe word slegs belangrik vir populasies se voortbestaan wanneer die mutualisme amper heeltemal verdwyn het.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Insect pollination contributes in various degrees toward the production of a variety of agricultural crops that ensure diversity and nutritional value in the human diet. Although managed honeybees (Apis mellifera L.) are still the most economically valuable pollinators of monoculture crops cultivated globally, wild pollinator communities can contribute substantially toward crop pollination through pollination ecosystem services sourced from neighbouring natural habitats. Pollination ecosystem services are thus valuable and can motivate for the protection of natural ecosystems hosting diverse insect pollinator communities. F1 onion hybrid seed production is entirely dependent on high insect pollinator activity to ensure cross pollination, seed set and profitable seed yields. Data was collected on 18 onion hybrid seed crops grown in the semi‐arid Klein Karoo and southern Karoo regions of the Western Cape, South Africa. These two main production regions are located within the Succulent Karoo biome, recognized as a global biodiversity hotspot of especially high plant diversity. It is also habitat to the indigenous Cape honeybee (Apis mellifera capensis Esch.). Sites selected varied in the percentages of available natural habitat and managed honeybee hives stocking density. Diverse anthophile assemblages were sampled with pan traps within all the onion fields, regardless of the percentage of available natural habitat near the crop. Crop management practices significantly affected the diversity of anthophile species caught within onion fields, although less than 20% of this diversity was observed actually visiting onion flowers. The honeybee (managed and wild) was by far the most important pollinator because of its high visitation frequency and regular substantial onion pollen loads carried on their bodies. Honeybee visitation significantly increased onion hybrid seed yield, while anthophile diversity and non‐Apis visitation had no effect on seed yield. Neither managed hive density, nor percentage natural habitat were important in determining honeybee visitation or seed yield. Total annual rainfall was the only significant factor determining honeybee visitation. Secondary factors caused by rainfall variability, such as wild flower abundance or soil moisture, may have significantly affected honeybee visitation. In addition, the positive correlation between honeybee visitation and the diversity of hand‐sampled insects from onion flowers; indicate that either or both onion varietal attractiveness and/or pollinator population size may have had significant effects on overall insect visitation. Honeybees showed marked discrimination between hybrid onion parental lines and preferred to forage on one or the other during single foraging trips. Hybrid onion parents differed significantly in nectar characteristics and onion flower scent which would encourage selective foraging through floral constancy. Interspecies interactions were insignificant in causing increased honeybee pollination because of the scarcity of non‐Apis visitors. Most farming practices are subjected to favourable environmental conditions for successful production. However, and especially in the South African context, the dependence of onion hybrid seed crops on insect pollination for successful yields, increase its reliance on natural ecosystem dynamics that may deliver abundant wild honeybee pollinators, or attract them away from the crops. Nevertheless, this dependence can be mitigated effectively by the use of managed honeybee colonies to supplement wild honeybee workers on the flowers. / AFRIKAANSE OPSOMMING: Insek bestuiwing dra in verskillende grade by tot die produksie van landbou gewasse wat variteit en voedingswaarde in die mens se dieet verseker. Al is die heuningby (Apis mellifera L.) steeds die waardevolste ekonomiese bestuiwer van verboude enkelgewasse, kan wilde bestuiwers wesenlik bydra tot gewasbestuiwing deur middel van ekosisteem dienste afkomstig van natuurlike habitatte. Bestuiwing ekosisteem dienste is daarom waardevol en kan dus die bewaring van natuurlike ekosisteme, wat diverse gemeenskappe huisves, regverdig. F1 basterui saadproduksie is totaal afhanklik van hoë insek‐bestuiwer aktiwiteit om kruisbestuiwing, saadvorming en winsgewende saadopbrengste te verseker. Data is ingesamel op 18 basterui saad aanplantings in die half‐droë Klein Karoo en suid‐Karoo streke van die Weskaap, Suid‐Afrika. Hierdie twee hoof produksie streke is geleë binne die Sukkulente Karoo bioom wat erken word as ʼn globale biodiversiteits “hotspot” met hoë plant diversiteit. Dit is ook die habitat van die inheemse Kaapse heuningby (Apis mellifera capensis Esch.). Aanplantings is gekies om verskillende grade van beskikbare natuurlike habitat en bestuurde heuningby korf digthede te verteenwoordig. Diverse versamelings blom‐besoekers is versamel met water‐wippe in al die aanplantings, ongeag die persentasie natuurlike habitat beskikbaar by elke aanplanting. Gewas bestuurspraktyke het die diversiteit van blombesoekers betekenisvol beïnvloed. Tog is minder as 20% van hierdie diversiteit as aktiewe besoekers op die uiekoppe waargeneem. Heuningbye (bestuur of wild) was oorwegend die belangrikste bestuiwers as gevolg van hoë besoek frekwensies en wesenlike ladings uiestuifmeel op hulle liggame. Heuningby besoeke het saadopbrengs betekenisvol verhoog, maar blom‐besoeker diversiteit en nie‐Apis besoeke het geen effek op saadopbrengs gehad nie. Bestuurde korf digtheid en persentasie natuurlike habitat was nie belangrik in die bepaling van heuningby besoeke of basterui saadopbrengste nie. Totale jaarlikse reënval was die enigste betekenisvolle faktor wat heuningby besoeke bepaal het. Sekondêre faktore wat versoorsaak word deur reënval veranderlikheid, soos veldblom volopheid of grondvog, kon betekenisvolle effekte op die aantal heuningby besoeke gehad het. Bykomend, dui die positiewe korrelasie tussen heuningby besoeke en die diversiteit van hand‐versamelde insekte vanaf die uiekoppe op die moontlike betekenisvolle effek van elk of beide basterui variteit aantreklikheid en/of bestuiwer populasie grote op algehele insek besoeke. Heuningbye het noemenswaardige diskriminasie getoon tussen die basterui ouerlyne en het verkies om op een of die ander te wei tydens enkele weidingstogte. Basterui ouerlyne het betekenisvol verskil in nektar eienskappe en blomgeur wat die selektiewe weiding van heuningbye, toegepas deur blomkonstantheid, sal aanmoedig. Tussen‐spesie interaksies was onbetekenisvol in die verhoging van heuningby bestuiwing omdat nie‐Apis besoekers baie skaars was. Meeste boerdery praktyke is onderhewig aan gunstige omgewings toestande vir suksesvolle produksie. Maar, en veral in die Suid‐Afrikaanse konteks, omdat basterui saad aanplantings afhanklik is van insek bestuiwing vir suksesvolle opbrengste, word daar meer staat gemaak op natuurlike ekosisteem dinamika wat volop wilde heuningby bestuiwers kan voorsien, of selfs bestuiwers van die aanplanting kan weg lok. Nietemin, hierdie afhanklikheid kan effektief verlaag word deur die gebruik van bestuurde heuningby kolonies om die aantal wilde heuningby werkers op die blomme aan te vul.

For over twenty years, flower-visitation networks have been used to assess the effects of pollinator decline, linked to habitat loss, climate change and invasive species, on entire communities. However, most rely on flower visit frequency as a proxy for pollination; very few sample pollen from flower visitor's bodies or from stigmas and so do not include a quantitative measure of pollination success. Here, I add pollinator effectiveness (as single visit pollen deposition) into a traditional flower visitation network, creating a pollinator importance network that better evaluates the flower visitor community from the plant's perspective. Given recent interest in pollination in urban areas, I use an urban garden habitat, and compare visitation, pollen transport and pollinator importance networks, giving several novel conclusions. Firstly, although there are similarities in the structure of my networks, interactions were most specialised in the pollinator importance network, with pollen transport proving to be a better proxy for pollinator importance than visitation alone. Secondly, the specialisation of individual plants and the role of individual flower visitors varied between the networks, suggesting that community-level patterns in simple visitation networks can mask important individual differences. Thirdly, the correlation between flower visit frequency and pollinator importance largely depends on bees, and may not hold in plant-pollinator communities that are not bee-dominated. Fourthly, heterospecific pollen deposition was relatively low, despite the unusually diverse plant community of a garden. Finally, bees (particularly Bombus and non-eusocial halictids) carried the largest pollen loads and were the most effective at depositing pollen on to the stigma during a single visit in this garden habitat. The implications of this thesis highlight the strengths and limitations of each network for future studies, and raise important questions for the future of urban pollination studies.

California's almond industry, valued at $2.3 billion per year, depends on the pollinator services of honey bees, although pollination by other insects, mainly solitary wild bees, is being investigated as an alternative because of recent declines in the number of honey bee colonies. Our objective is to model the movements of honey bees and determine the conditions under which they will forage in less favorable areas of a tree and its surroundings when other pollinators are present. We hypothesize that foraging in less favorable areas leads to increased movement between trees and increased cross pollination between varieties which is required for successful nut production. We use the Shigesada-Kawasaki-Teramoto model (1979) which describes the density of two species in a two-dimensional environment of variable favorableness with respect to intrinsic diffusions and intra- and interspecific interactions of species. The model is applied to almond pollination by honey bees and other pollinators with environmental favorableness based on the distribution of flowers in trees. Using the spectral-Galerkin method in a rectangular domain, we numerically approximated the two-dimensional nonlinear parabolic partial differential system arising in the model. When cross-diffusion or interspecific effects of other pollinators was high, honey bees foraged in less favorable areas of the tree. High cross-diffusion also resulted in increased activity in honey bees in terms of accelerations, decelerations, and changes in direction, indicating rapid redistribution of densities to an equilibrium state. Empirical analysis of the number of honey bees and other visitors in two-minute intervals to almond trees shows a negative relationship, indicating cross-diffusion effects in nature with the potential to increase movement to a different tree with a more favorable environment, potentially increasing nut production.

Unlike other rosaceous fruit crops such as apple and cherry, commercial raspberry cultivars are largely self-fertile and can set fruit in the absence of pollinators. However, their floral morphology often prevents complete self-pollaintion. Incomplete pollination yields unmarketable small or crumbly fruits. Insect visitation is therefore essential to maximizing raspberry yield. Honey bees are typically used to pollinate commercial raspberry; however, escalating prices for hive rentals coupled with increasing acreage encourage evaluation of other manageable pollinators. Bumble bees (Bombus spp.) and several mason bees (Osmia spp.) are promising raspberry pollinators. Five bee species were evaluated and compared for their single-visit pollination efficacies on raspberry. From this a pollinator effectiveness index was created and an estimation of the minimum number of visits required to maximize fruit set was calculated. This estimation was then experimentally verified. Finally, in an attempt to synchronize their brief activity period with raspberry bloom, winter management options aimed at delaying the emergence of the mason bee, O. lignaria, were investigated. All five bee species proved excellent pollinators of raspberry. None of the alternative manageable species greatly outperformed honey bees. For this reason honey bees remain the most economical and practical option for open-field raspberry pollination. The adoption of alternative manageable bees could still be justified in other production systems, such as high-tunnel or greenhouse grown raspberry, which hamper honey bees’ ability to forage effectively. The pollinator effectiveness score for honey bees suggested that as few as two visits can achieve maximum fruit set. This estimate was confirmed through experimentation on three different red raspberry cultivars. For two of these cultivars, just one visit yielded drupelet counts similar to openly-pollinated flowers. This information can be used to help refine stocking density estimates for honey bees on raspberry. Wintering bees at 0° or -3° C rather than 4° C effectively delayed emergence of O. lignaria by more than a month without any impact on post-winter performance. These results suggest winter storage at near freezing temperatures is a viable management option for the use of O. lignaria with later-blooming crops.

Bee declines have been reported globally and habitat loss and degradation due to urbanization and agricultural intensification are two of the primary drivers. Native bees play a critical role in plant reproduction, and declines in abundance and diversity of bees are expected to impact flowering plant biodiversity and productivity of insect pollinated agricultural crops. Habitat restoration can help mitigate declines by increasing the amount and quality of available bee habitat. However, outside of agroecosystems bees are rarely specified in restoration targets and little is known about how they respond to habitat restoration. My thesis addresses this knowledge gap by: (1) documenting the structure and function of the native bee community at a restored wet meadow to establish a baseline for future monitoring activities, (2) comparing the influence of two restoration approaches on the established bee community, and (3) exploring changes in functional groups and pollination function with time since restoration. I sampled bees at degraded, restored, and (semi)natural habitats at 12 sites in four locations in southern Ontario. I used a combination of structural (abundance, richness, and evenness) and functional (guilds based on social and nesting habits and plant-pollinator interaction networks) characteristics to describe and compare bee communities. I collected a total of 10,446 bees from 30 genera and six families representing a range of phenologies, social behaviours, and nesting habits. At Dunnville Marsh, a restored wet meadow, I collected 5,010 bee specimens from 27 genera and six families. The bee community at Dunnville Marsh was diverse and well connected within 4-6 years of restoration, emphasizing the importance of wet meadows as native bee habitat. However, wood nesters and cleptoparasites were relatively uncommon suggesting that the community may be less stable compared to older habitats. Between 2005 and 2008, individual fields at Dunnville Marsh were dug with pits and mounds before planting and seeding or were seeded into weedy ground. Digging pits and mounds did not convey a clear advantage to the establishing bee community, but genus richness was greater in pit and mound sites (p=0.04). As well, the restoration approach used influenced the relative representation of guilds within the community. Ground nesters and wood nesters were significantly more abundant in pit and mound treated sites (p<0.001), perhaps reflecting the larger amounts of bare ground (p<0.001) and the greater potential for sapling survival on mound tops. Stem nesters were more abundant in planted sites (p<0.001), and floral richness and abundance did not differ between the two restoration approaches. Finally, diversity and evenness of guilds based on social and nesting habits increased with age since restoration, indicating that communities in (semi)natural habitats are more functionally diverse than those in restored habitats, but that communities in restored habitats are more functionally diverse than those in degraded habitats. Relative abundance of guilds changed with age since restoration in ways that reflected structural habitat changes associated with succession. Degraded sites had the highest relative abundance of ground nesters, while (semi)natural sites had the highest relative abundance of wood nesters. Plant-pollinator interaction networks did not demonstrate clear trends with respect to age since restoration, but indicated that communities that establish in response to non-targeted restorations can be diverse, robust to extinction, and well connected.

Anemofiliniai augalai kasmet žiedadulkes ore paskleidžia netolygiai – įvairiais kiekiais, skirtingomis dienomis ir sudaro nevienodo ilgio žiedadulkių sklaidos sezonus. Anemofilinių augalų žiedadulkių sklaidos ore prognozės kasmet tampa vis svarbesniu reiškiniu visuomenėje, kurioje stebimas intensyvėjantis žiedadulkėse esančių alergenų neigiamas poveikis žmonių sveikatai. / In every year anemophylous plants are distributing pollens unequal in the air – in different amount or different day and are creating various lengths of pollination seasons. Forecasting of anemophylous plants pollination in every year is more and more important subject for society, in which is observing negative influence intensify of pollens allergens for humans’ health.