Thomas Tscheulin

• PhD in Population Ecology, Imperial College London, UK
• Professor (Associate; tenured) at University of the Aegean

Ever since wild bees’ role as pollinators received more attention, wild bee conservation has become an increasing concern. The importance of wild bees as pollinators has taken a back seat to honey bees for decades thanks to their well known efficiency. This chapter will discuss the impact that humans have on wild bees, starting with a summary on wh...

Simple Summary The olive fly is a major pest that threatens olive trees worldwide. It attacks olives, reducing both the quantity and quality of the harvest. This can disrupt supply chains and lead to economic losses for farmers and businesses. To combat this pest, farmers often rely on chemical insecticides, which can harm the environment and benef...

Organisms may simultaneously face thermal, desiccation and nutritional stress under climate change. Understanding the effects arising from the interactions among these stressors is relevant for predicting organisms' responses to climate change and for developing effective conservation strategies. Using both dynamic and static protocols, we assessed...

Olive groves, a major cultivation in Mediterranean basin, faces increasing challenges from pests like the olive fly [Bactrocera oleae (Rossi) (Diptera: Tephritidae)]. To mitigate these threats and promote sustainable practices, understorey management emerges as a promising strategy. Understorey, the area beneath the olive trees, plays a pivotal rol...

The agricultural industry is intensifying production methods to increase crop yields. Olive cultivation, the prevalent permanent crop in Europe and the Mediterranean area, involves intense practices with heavy agrochemical use. This significantly impacts agroecosystem biodiversity and its ecosystem services. In this study, we explore how biodiversi...

Population Dynamics of the Olive Fly, Bactrocera oleae (Diptera: Tephritidae), Are Influenced by Different Climates,Seasons, and Pest Management. Abstract: Pest management practices interact with many species and have an impact on the ecology and the economy of the area. In this paper, we examine the population dynamics of the olive fly, Bactrocera...

Cultivation of olive-trees is one of the landmark land-uses and agroecosystems of the Mediterranean. The single most important factor of production-loss is infestation by the olive fruit fly (OLF, Bactrocera oleae). We examine the spatiotemporal dynamics of OLF populations on Samos Island by employing spatial-analysis methods for a focused estimati...

The agricultural sector has been intensifying production systems to increase yields. Olive cultivation is the most widespread permanent crop in Europe and the Mediterranean region and in many cases, it is under intensive farming practices with heavy use of agrochemicals, greatly affecting olive grove biodiversity. In this study we investigate the i...

Livestock overgrazing causes environmental degradation, species invasion, biodiversity loss, and productivity decline, with profound consequences for ecological sustainability and human livelihoods. Habitat protection can mitigate such impacts, but we know little about how the long‐term recovery of plant communities from livestock overgrazing depen...

Bees are essential pollinators and understanding their ability to cope with extreme temperature changes is crucial for predicting their resilience to climate change, but studies are limited. We measured the response of the critical thermal maximum (CTMax) to short-term acclimation in foragers of six bee species from the Greek island of Lesvos, whic...

The olive fruit fly ( Bactrocera oleae ) (Rossi) is the most economically important insect pest in many olive cultivation areas worldwide. However, levels of infestation by this pest show remarkable variability, even among orchards in close proximity to one another. While the factors driving this variability remain uncertain, there is evidence that...

Pest management practices interact with many species and have an impact on the ecology and the economy of the area. In this paper, we examine the population dynamics of the olive fly, Bactrocera oleae (Rossi), Diptera: Tephritidae, on Samos Island, Greece, observing the spatial and temporal changes of the pest along an altitude associated with area...

The management of natural enemies of perennial tree crops and especially insects is performed with pesticides, which can negatively impact the quality of products, natural resources and biodiversity as well as the health of producers and consumers. An emerging trend focuses alternatively on the use of less or no chemicals and the management of crop...

The management of natural enemies of perennial tree crops and especially insects, is usually performed with pesticides, which can negatively impact the quality of products, natural resources, and biodiversity, as well as the health of producers and consumers. An emerging trend focuses alternatively on the use of less or no chemicals and the managem...

The management of pests is an area where different objectives meet: the need to ensure that agricultural production covers the needs of a growing population, the need to ensure safety and low levels of health risks for people and the need to conserve wildlife and biodiversity are not always compatible. In this chapter, we present precision farming...

Premise: Capparis spinosa is a widespread charismatic plant, in which the nocturnal floral habit contrasts with the high visitation by diurnal bees and the pronounced scarcity of hawkmoths. To resolve this discrepancy and elucidate floral evolution of C. spinosa, we analyzed the intrafloral patterns of visual and olfactory cues in relation to the...

Τα συστήματα γεωργίας ακριβείας προβάλλονται ως η επόμενη επανάσταση στην αγροτική παραγωγή, η οποία θα προσφέρει περισσότερα εργαλεία και δεδομένα στα χέρια των παραγωγών όσον αφορά στην επίδραση του χώρου και αβιοτικών παραμέτρων στην παραγωγή και στη διαχείριση εχθρών και ασθενειών. Από την άλλη όμως απαιτεί κεφάλαια και γνώσεις ή δυνατότητα πρό...

The management of natural enemies of perennial tree crops and especially insects is performed with pesticides, which can negatively impact the quality of products, natural resources and biodiversity as well as the health of producers and consumers. An emerging trend focuses alternatively on the use of less or no chemicals and the management of crop...

Η καταπολέμηση των εχθρών μόνιμων καλλιεργειών και ιδιαίτερα εντόμων, γίνεται σήμερα με τη χρήση φυτοπροστατευτικών ουσιών που μπορεί να έχουν αρνητικές επιπτώσεις τόσο στην ποιότητα των παραγόμενων προϊόντων, όσο και στο περιβάλλον, τη βιοποικιλότητα και την υγεία των παραγωγών και καταναλωτών. Αναδύεται όμως ταυτόχρονα, μια τάση που προσανατολίζε...

Η καταπολέμηση των εχθρών μόνιμων καλλιεργειών και ιδιαίτερα εντόμων, γίνεται σήμερα συνήθως με τη χρήση φυτοπροστατευτικών που μπορεί να έχουν αρνητικές επιπτώσεις στην ποιότητα των προϊόντων και στο περιβάλλον και τη βιοποικιλότητα. Αναδύεται μια τάση προς χρήση λιγότερων ή καθόλου φυτοπροστατευτικών και καταπολέμηση ή έλεγχο των εχθρών των καλλι...

The impending temperature rise during the 21st century is expected to have a negative impact on plant communities, especially in Mediterranean ecosystems, causing changes in the availability of floral rewards, such as quantity and quality of floral nectar. Floral nectar is important in pollination and consequently for ecosystem functioning. The pre...

The bee family Halictidae is considered to be an optimal model for the study of social evolution due to its remarkable range of social behaviors. Past studies in circadian rhythms suggest that social species may express more diversity in circadian behaviors than solitary species. However, these previous studies did not make appropriate taxonomic co...

Maintaining the diversity of wild bees is a priority for preserving ecosystem function and promoting stability and productivity of agroecosystems. However, wild bee communities face many threats and beekeeping could be one of them, because honey bees may have a strong potential to outcompete wild pollinators when placed at high densities. Yet, we s...

There is increasing interest in developing urban design principles that incorporate good ecological management. Research on understanding the distribution and role of beneficial pollinating insects, in particular, is changing our view of the ecological value of cities. With the rapid expansion of the built environment comes a need to understand how...

Anthropogenic environmental change exposes biological communities to concurrent stressors (e.g., changes in climate and land-use, overexploitation, biotic invasions) that frequently persist over prolonged periods. Predicting and mitigating the consequences of human action on nature therefore requires understanding how exposure to multiple interacti...

Aim We studied bumblebee diversity and bumblebee pollination networks along the altitudinal gradient of Mt. Olympus, a legendary mountain in Central Greece, also known for its exceptional flora. Location Mt. Olympus, Central Greece. Taxon Bombus (Latreille, 1802). Methods We explored 10 study sites located on the north‐eastern slope of the mount...

Monitoring pollinator health and pollination is among the top priorities to safeguard pollinators and secure pollinator services. Assessments of sampling methods are therefore essential for developing a standardized protocol for long-term pollinator monitoring. Pan trapping is a popular technique to survey pollinators, but limited information is av...

1. Thermal tolerance has a strong predictive power for understanding the ecology and distribution of organisms, as well as their responses to changes in land use and global warming. However, relatively few studies have assessed thermal tolerances for bees. 2. The present study aimed to determine whether the critical thermal maximum (CT max ) of car...

Pollination by insects is a key input into many crops, with managed honeybees often being hired to support pollination services. Despite substantial research into pollination management, no European studies have yet explored how and why farmers managed pollination services and few have explored why beekeepers use certain crops. Using paired surveys...

Global transportation of plants and animals is increasingly causing new pest invasions. Α recent example is Drosophila suzuki Matsumura (Diptera: Drosophilidae), one major pest of thin exterior fruit in Greece and other European countries. In this paper, some preliminary findings of population fluctuation of male D. suzuki in the orchards of Almopi...

Email: g.Katsikogiannis@samos.gr , a.kizos@aegean.gr Περίληψη-Μεθοδολογία Ο δάκος της ελιάς, Bactrocera oleae Rossi (Diptera: Tephritidae) αποτελεί τον σοβαρότερο εχθρό της ελαιοκαλλιέργειας, λόγω των οικονομικών επιπτώσεων από τις ζημιές που προκαλεί στην ελαιοπαραγωγή κάθε έτος. Το πρόγραμμα συλλογικής καταπολέμησης του δάκου, για να είναι αποτελ...

Worldwide urbanisation and use of mobile and wireless technologies (5G, Internet of Things) is leading to the proliferation of anthropogenic electromagnetic radiation (EMR) and campaigning voices continue to call for the risk to human health and wildlife to be recognised. Pollinators provide many benefits to nature and humankind, but face multiple...

Fire, a frequent disturbance in the Mediterranean, affects pollinator communities. We explored the response of major pollinator guilds to fire severity, across a fire‐severity gradient at different spatial scales. We show that the abundance of all pollinator groups responded to fire severity, and that bees and beetles showed in addition a significa...

To monitor and quantify the changes in pollinator communities over time, it is important to have robust survey techniques of insect populations. Pan traps allow for the assessment of the relative insect abundance in an environment and have been promoted by the Food and Agricultural Organization (FAO) as an efficient data collection methodology. It...

Aim Understanding which factors drive α‐ and β‐diversity is fundamental to ecological and biogeographical research. Especially in archipelagos, diversity patterns are interesting due to the numerous factors influencing them. Here, we investigate the importance of climate and ecogeographical factors in shaping α‐ and β‐diversity patterns of bee spec...

Floral nectar is a vital resource for pollinators, thus having a very important role in ecosystem functioning. Ongoing climate warming could have a negative effect on nectar secretion, particularly in the Mediterranean, where a strong temperature rise is expected. In turn, decreased nectar secretion, together with shifts in flowering phenology can...

Comparing traits of invasive species within and beyond their ancestral range may improve our understanding of processes that promote aggressive spread. Solanum elaeagnifolium (silverleaf nightshade) is a noxious weed in its ancestral range in North America and is invasive on other continents. We compared investment in flowers and ovules, pollinatio...

Supplementary Figures 1-4; Supplementary Tables 1-8

Despite progress in understanding pollination network structure, the functional roles of floral sensory stimuli (visual, olfactory) have never been addressed comprehensively in a community context, even though such traits are known to mediate plant-pollinator interactions. Here, we use a comprehensive dataset of floral traits and a novel dynamic da...

The weighted plant-pollinator interactions network including 41 plant and 168 insect species, recorded in a Mediterranean scrubland (phrygana) in Lesvos Island, Greece.

Inflorescence volatile compounds of the plant species studied.

Most agricultural grassland in lowland UK is species-poor and structurally uniform. Management intensification has had a deleterious affect on the biodiversity of invertebrates and the suitability of grassland as feeding and breeding habitat for birds (Vickery et al. 20001). The PEBIL project (Defra BD 1444: Potential for Enhancing Biodiversity in...

Fire affects diversity and structure of flower-visitor communities. We explored the effect of fire history on the diversity patterns and structure of the flower-visitor guilds (bees, beetles, flies, sawflies, and wasps), across a post-fire regeneration sequence of pine forests in Rhodes Island, Greece. Fire history was defined by fire frequency and...

The majority of studies investigating the effects of landscape composition and configuration on bee populations have been conducted in regions of intensive agricultural production, ignoring regions which are dominated by seminatural habitats, such as the islands of the Aegean Archipelago. In addition, research so far has focused on the landscape im...

Honey bees are globally regarded as important crop pollinators and are also valued for their honey production. They have been introduced on an almost worldwide scale. During recent years, however, several studies argue their possible competition with unmanaged pollinators. Here we examine the possible effects of honey bees on the foraging behaviour...

The exponential increase of mobile telephony has led to a pronounced increase in electromagnetic fields in the environment that may affect pollinator communities and threaten pollination as a key ecosystem service. Previous studies conducted on model species under laboratory conditions have shown negative effects of electromagnetic radiation (EMR)...

The structure of pollination networks is an important indicator of ecosystem stability and functioning. Livestock grazing is a frequent land use practice that directly affects the abundance and diversity of flowers and pollinators and, therefore, may indirectly affect the structure of pollination networks. We studied how grazing intensity affected...

1. Pollinating insects provide important ecosystem services and are influenced by the intensity of grazing. Based on the Intermediate Disturbance Hypothesis ( IDH ), pollinator diversity is expected to peak at intermediate grazing intensities. However, this hump‐shaped relationship is rarely found. 2. The effect of grazing intensity was tested on f...

Fire is an important and frequent disturbance in Mediterranean-type ecosystems affecting the structure and dynamics of bee communities. We explored the effect of fire history on taxonomic and functional composition of wild bees on Rhodes Island, Greece, using UV-bright pan trap sampling. We carried out a fourth-corner analysis based on Generalized...

The objective of this study was to obtain a biogeographical perspective on the hoverfly genus Merodon (Diptera, Syrphidae) based on data from 32 islands in the Aegean and Ionian archipelagoes vis‐à‐vis the adjacent mainland. In this part of the world, the genus comprises 57 species, out of more than 160 species described worldwide. The importance o...

The architectural complexity of flower structures (hereafter referred to as floral complexity) may be linked to pollination by specialized pollinators that can increase the probability of successful seed set. As plant-pollinator systems become fragile, a loss of such specialized pollinators could presumably result in an increased likelihood of poll...

Global warming can lead to considerable impacts in natural plant communities, potentially inducing changes in plant physiology and the quantity and quality of floral rewards, especially nectar. Changes in nectar production can in turn strongly affect plant-pollinator interaction networks - pollinators may potentially benefit under moderate warming...

The structure of pollination networks is an important indicator of ecosystem stability and functioning. Livestock grazing is a frequent land use practice that directly affects the abundance and diversity of flowers and pollinators and, therefore, may indirectly affect the structure of pollination networks. Here we studied how grazing intensity affe...

Background/Question/Methods Pollinating insects provide important ecosystem services and the structure of pollination networks is an important indicator of ecosystem stability and functioning. Livestock grazing is a frequent land use practice that directly affects the abundance and diversity of flowers and pollinators, and therefore, may indirectly...

The Eastern Mediterranean is a biodiversity hotspot of global importance. Greece, owing to its geographic particularities and turbulent natural history, shares a large part of this biotic uniqueness. Wild bees and orchids are two groups that show high diversity in the Aegean Archipelago. According to the most recent floristic assessment, 101 orchid...

Plant traits are direct indicators of plants’ habits, needs and function, and as such they may predict vulnerability. Among them, floral traits are directly associated with reproduction and, subsequently, the population sizes of insect-pollinated plants. Nevertheless, efforts that describe and analyze the role of these traits regarding the actual c...

Pollination services are economically important component of agricultural biodiversity which enhance the yield and quality of many crops. An understanding of the suitability of extant habitats for pollinating species is crucial for planning management actions to protect and manage these service providers. In a highly modified agricultural ecosystem...

Το γένος Eumerus (Δίπτερα: Συρφίδες) είναι από τα πλέον ποικίλα γένη συρφίδων στην περιοχή των Βαλκανίων, με περίπου 50 είδη περιγραμμένα, εκ των οποίων >20 είδη εντοπίζονται στα νησιά του Αιγαίου. Η κλασική ταξινομική συνήθως αποτυγχάνει στην ορθή αναγνώριση των ειδών (μη ολοκληρωμένες κλείδες, προβλήματα στην ονοματολογία), καθιστώντας την χρήση...

Ερευνήθηκαν εγγενείς και εξωγενείς παράγοντες που δυνητικά επιτείνουν την τρωτότητα των σπάνιων και απειλούμενων taxa της ελληνικής χλωρίδας, όπως αυτά καταγράφονται στα Βιβλία Ερυθρών Δεδομένων του 1995 και 2009. Ως εξωγενείς παράγοντες θεωρήθηκαν τα χωρικά χαρακτηριστικά κάθε taxon (π.χ. το υψόμετρο, ο βιότοπος, ο βαθμός ενδημισμού, η μέγιστη από...

Co-flowering plant species commonly share flower visitors, and thus have the potential to influence each other's pollination. In this study we analysed 750 quantitative plant-pollinator networks from 28 studies representing diverse biomes worldwide. We show that the potential for one plant species to influence another indirectly via shared pollinat...

Background. Up to 75% of crop species benefit at least to some degree from animal pollination for fruit or seed set and yield. However, basic information on the level of pollinator dependence and pollinator contribution to yield is lacking for many crops. Even less is known about how insect pollination affects crop quality. Given that habitat loss...

Background. Up to 75 % of crop species benefit at least to some degree from animal pollination for fruit or seed set and yield. However, basic information on the level of pollinator dependence and pollinator contribution to yield is lacking for many crops. Even less is known about how insect pollination affects crop quality. Given that habitat loss...

Background. Up to 75 % of crop species benefit at least to some degree from animal pollination for fruit or seed set and yield. However, basic information on the level of pollinator dependence and pollinator contribution to yield is lacking for many crops. Even less is known about how insect pollination affects crop quality. Given that habitat loss...

In the framework of the project THALES: The Pollinators of the Aegean, Biodiversity and Threats (2012-2015), 1732 plants were collected from four floristic regions including a total of 20 Aegean islands (Anafi, Chios, Iraklia, Ikaria, Ios, Karpathos, Kea, Kos, Lesvos, Limnos, Milos, Mykonos, Naxos, Paros, Rhodes, Samothrace, Thasos, Thera, Serifos,...

Worldwide, there is a well-documented crisis for bees and other pollinators which represent a fundamental biotic capital for wild life conservation, ecosystem function, and crop production. Among all pollinators of the world, bees (Hymenoptera: Apoidea) constitute the major group in species number and importance, followed by hover flies (Diptera: S...

Invasive plants can impact biodiversity and ecosystem functioning by displacing native plants and crop species due to competition for space, nutrients, water and light. The presence of co-flowering invasives has also been shown to affect some native plants through the reduction in pollinator visitation or through the deposition of heterospecific po...

Land-use changes can alter the spatial population structure of plant species, which may in turn affect the attractiveness of flower aggregations to different groups of pollinators at different spatial scales. To assess how pollinators respond to spatial heterogeneity of plant distributions and whether honeybees affect visitation by other pollinator...

The decline of bees has raised concerns regarding their conservation and the maintenance of ecosystem services they provide to bee-pollinated wild flowers and crops. Although the Mediterranean region is a hotspot for bee species richness, their status remains poorly studied. There is an urgent need for cost-effective, reliable, and unbiased samplin...

Plant population size has been shown to affect insect visitation and reproductive success. Small populations are at risk because individuals are more likely to be affected by stochastic processes and inbreeding depression (Allee effect). Additionally, several studies have found that plants in small populations also experience lower pollinator visit...