TO TOP

WILD BEES IN THE BOTANIC GARDEN

by Christopher Bause from the team of PD Dr. Thomas Eltz (Chair of Evolutionary Ecology & Biodiversity of Animals, Prof. Dr. Ralph Tollrian)

There are almost 600 species of wild bees in Germany. In contrast to honey bees, the vast majority of wild bees do not live together in large colonies, but as solitary individuals. Many wild bee species prefer to colonise dry, warm and open landscapes. Wild bees place high demands on their habitats. They need diverse landscapes with hedges, dead wood, open areas of bare ground and, of course, plenty of wildflowers.


Lupe
common carder bee (Bombus pascuorum) on spring vetch (Lathyrus vernus, Fabaceae)
© RUB / Christopher Bause

Wild bees don't have it easy

Unfortunately, wild bees have a very difficult time nowadays in our cultural landscape, dominated by industry and agriculture. There is usually a lack of suitable nesting sites or materials and the variety of suitable forage plants is also very limited. However, some species of wild bees also feel quite at home in urban areas. Stille, even here, species-poor, gravelled front gardens and exclusively green parks without wildflowers do not make life easier for wild bees.


Lupe
In our species-poor cultural landscape, many wild bee species find it very difficult to find food and suitable nesting sites


The wild bee hotel in the Botanic Garden

Here in the Botanical Garden of the Ruhr University Bochum there is still a variety of habitats and, of course, a large variety of wildflowers. Wild bees find many nesting opportunities here, such as dry stone walls, dead wood and more or less open, sandy patches of soil. In the specially provided wild bee "hotel" in our medicinal garden, there are also hollow plant stems, wood with boreholes and a simulated cliff face made of loam.

 

Photo left: Our wild bee hotel in the medicinal garden - © RUB / Wolfgang Stuppy


Wild bees have specialised diets

As far as their food is concerned, wild bees are often very specialised and only collect pollen from a certain group of plants to feed their offspring. With pollen from other plants the next generation could not develop. Wild bees species that are highly specialised in certain plant species are called 'oligolectic'. They only occur where they can find their pollen plants. If the right plant is missing, then the corresponding bee is also absent.

 

Photo right: Die small sallow mining bee (Andrena praecox) is specialised on willow pollen (Salix spp., Salicaceae) which it collects on its hind legs - © RUB / Christopher Bause


Honey bees are less picky

Unlike wild bees, honey bees are 'polylectic', which means that they collect pollen and nectar from a variety of different plant species. They are therefore more adaptable and also cope very well with non-native plants in gardens and parks. There are also numerous species of wild bees that are not very picky when it comes to their food plants - bumblebees!

 

Photo left: honey bees (Apis mellifera) are not very picky and collect pollen and nectar from many different plants, here from winter heath (Erica carnea, Ericaceae) - © RUB / Christopher Bause



Wild bee species found in the Botanic Garden

(click on the picture to enlarge!)

bryony mining bee (<i>Andrena florea</i>, female) - specialised on bryony (<i>Bryonia</i> spp., Cucurbitaceae); photo: C. Bause large earth bumblebee (<i>Bombus terrestris</i>, wueen) on fragrant honeysuckle (<i>Lonicera fragantissima</i>, Caprifoliaceae); photo: C. Bause buffish mining bee (<i>Andrena nigroaenea</i>, female) on flowers of summer savoury (<i>Satureja hortensis</i>, Lamiaceae) - unspecialised species; photo: C. Bause small sallow mining bee (<i>Andrena praecox</i>, female) - appears very early in the year, specialised on willows (<i>Salix</i> spp.,Salicaceae); photo: C. Bause </i>common carder bee (<i>Bombus pascuorum</i>) on spring vetch (<i>Lathyrus vernus</i>, Fabaceae); photo: C. Bause hairy-footed flower bee (<i>Anthophora plumipes</i>, female) on purple dead-nettle (<i>Lamium purpureum</i> Lamiaceae) - a very early, unspecialised species; photo: C. Bause common mourning bee (<i>Melecta albifrons</i>) auf ground ivy (<i>Glechoma hederacea</i>, Lamiaceae) - brood parasite of the hairy-footed flower bee (<i>Anthophora plumipes</i>); photo: C. Bause garden bummble bee (<i>Bombus hortorum</i> worker) on bugle (<i>Ajuga reptans</i>, Lamiaceae); photo: C. Bause white-tailed bumblebee (<i>Bombus</i> cf. <i>lucorum</i>, worker) on cow parsley (<i>Anthriscus sylvestris</i>, Apiaceae); photo: C. Bause viper's bugloss mason bee (<i>Hoplitis adunca</i>, female) whilst sun bathing; specialised on viper's bugloss (<i>Echium vulgare</i>, Boraginaceae); photo: C. Bause viper's bugloss mason bee (<i>Hoplitis adunca</i>, male) whilst sun bathing; specialised on viper's bugloss (<i>Echium vulgare</i>, Boraginaceae); photo: C. Bause white-lipped blood bee (<i>Sphecodes albilabris</i>, female), brood parasite of the spring mining bee (<i>Colletes cunicularius</i>) and other species of wild bee; photo: C. Bause red-tailed bumblebee (<i>Bombus lapidarius</i>, worker) on sweet yellow clover (<i>Melilotus officinalis</i>, Fabaceae); photo: C. Bause great banded furrow-bee (<i>Halictus scabiosae</i>, female), largely unspecialised, social species forming small colonies; photo: C. Bause blue mason bee (<i>Osmia caerulescens</i>, female) on hedge woundwort (<i>Stachys sylvatica</i>, Lamiaceae), unspecialised species; photo: C. Bause blackish blunt-horn (<i>Melitta nigricans</i>, female) on purple loosestrife (<i>Lythrum salicaria</i>, Lythraceae) - the green pollen on the hind legs belongs to purple loosestrife; photo: C. Bause European orchard bee (<i>Osmia cornuta</i>, male) unspecialised, common species; photo: C. Bause European orchard bee (<i>Osmia cornuta</i>) - mating (female below), unspecialised, common species; photo: C. Bause early bumblebee (<i>Bombus pratorum</i>, queen) on <i>Prunus</i> spec.; photo: C. Bause tree bumblebee (<i>Bombus hypnorum</i>, queen) on grape hyacinth (<i>Muscari</i> spec.); photo: C. Bause Clark's mining bee (<i>Andrena clarkella</i>, female) specialised on willows (<i>Salix</i> spp., Salicacae); photo: C. Bause early nomad bee (<i>Nomada leucophthalma</i>, female) brood parasite of Clark's mining bee (<i>Andrena clarkella</i>); photo: C. Bause early mining bee (<i>Andrena haemorrhoa</i>, female) on sloe (<i>Prunus spinosa</i>), unspecialised, common species; photo: C. Bause broad-faced mining bee (<i>Andrena proxima</i>, female) on ground elder (<i>Aegopodium podograria</i>, Apiaceae), specialised on members of the carrot family (Apiaceae); photo: C. Bause