Heriades bees

Summary

Honey bees are not the only bee species that are significant for human wellbeing. Heriades bees are a group of native bee species that do not produce honey but are important pollinators of crops and wild plants. Females have a sting, but they are not aggressive and will only sting if handled. Heriades bees are dark-coloured, of slender to medium build and have a fairly sparse covering of body hairs. They live independently of others (i.e. they are solitary) and build their nests in the ground. This fact sheet provides information about these bees to encourage farmers to understand and protect them to help ensure that their crops are effectively pollinated.

From a conservation and agricultural standpoint it is not necessary to recognise all the different bee genera. However, it is important to know that there is a large bee biodiversity. Different bee genera pollinate different plant species, although there is some overlap that acts as a buffer as bee populations wax and wane. For healthy ecosystems, including agro-ecosystems both diversity and abundance in the bee fauna is important.

Scientific Classification

Kingdom: Animalia

Phylum: Arthropoda

Class: Insecta

Order: Hymenoptera

Family: Megachilidae

Subfamily: Megachilinae

Tribe:  Osmiini

Genus: Heriades Spinola, 1808

Species in the Genus

There are many bee species in the genus Heriades and they are found throughout the world.

Species in Kenya, Tanzania & Uganda

Nine species have been recorded from Kenya , Tanzania and Uganda (Eardley and Urban 2010). but more detailed survey work is needed to provide more accurate information on the number of species in these countries and their distributions.

Description

Heriades bees are not well known by local people (including farmers) inEast Africa. These insects are usually not recognised as bees by local people in East Africa , where the name bee is generally thought only to apply to honey bees. Their taxonomy is yet fully explored by scientists in East Africa. Heriades bees are dark and of slender to medium build with fairly sparse body hairs.

Possible Causes of Confusion

Some insect species look like Heriades bees. These are very commonly mistaken for "black ants". Due to their small size, it is easy to confuse them with ants and other wasps feeding of floral resources in fields.

Distribution in Kenya, Tanzania & Uganda

The genus Heriades is found in most districts/regions ofUganda, Kenya and Tanzania.

Habitats

Bees of the genus Heriades can be found in various habitats (land-uses) in East Africa such as grasslands, natural forests, wetlands, marshlands, open habitats, protected areas, farmlands, rangelands, woodlands, woodlots (forest plantations), riparian areas.Uganda, they are commonly recorded near and degraded forest habitats. In Uganda these bees are frequently collected in shaded and undisturbed sites found in natural and semi-natural habitats across all types of landscapes.

Nesting

These bees are solitary bees with a variety of ground- and twig-nesting behaviours (Michener 2007). In Uganda, they are found nesting in shaded and dry soils structures found in different vegetation layers of secondary and primary forests.

Crops Visited

Bees of the genus Heriades in East Africa are polylectic, collect nectar and pollen from various flowering crop species belonging to different plant families found inEast Africa. These bees are efficient pollinators of crops such as coffee, eggplant, beans, cowpeas, simsim (sesame), passion fruits, apples, cocoa, mango, avocado, egg plants, tomato, coffee, sunflowers, etc.

Other Plants Visited

InEast Africa, these bees visit various plant species, particularly those in the family of Fabaceae, Malvaceae, Rubiaceae, Asteraceae, etc. In East Africa, Heriades are wild bees that visit various wild plant species (trees, shrubs, herbs, weeds, lianas, grasses) found in different habitats. These bees visit preferably plant species of small flowers of white, milk-cream, yellow and purple colours.

Economic / Ecological Importance

Little information exists on the usefulness of these bees to the lives of the people in East Africa. However, they are pollinators and thus they are likely to contribute to increased agricultural productivity and the conservation of the natural biological diversity of the region.

Threats

InEast Africa, Heriades bees and other bee taxa are threatened by factors such as habitat degradation, agricultural intensification (e.g. replacing hedges with barbed wire fences, and increased use of herbicides which can affect wild flower numbers), the misuse of insecticides and trampling of nests by livestock and people. Farming practices that involve over-digging of soils are likely to threaten populations of these bees since they nest in the ground. Heriades bee populations in East Africa are likely to be affected by pests and diseases but information on this subject is lacking. The lack of knowledge of about these bees and their economic importance by people (de facto custodians of nature) is significant as their conservation and management practices implemented at the farm level will depend to a large extent upon the value that people attach to them.

Conservation and Management Practices

Little information exists on the usefulness of these bees to the lives of the people in East Africa . However, there are now concerted research efforts in the region to develop best practices for conservation and management of bees that are compatible with other good farm practices, to enhance crop production. Theoretically, bee conservation and management is inexpensive and adopted activities can also improve the aesthetic value of the landscape. Such practices involve setting land aside (e.g. a 1-metre strip) in the farmland to host all year round food resources for the bees, as well as safer sites for nesting, mating, resting and refuge from natural enemies. During flowering, farmers should manage pesticide usage carefully to avoid poisoning flower-visiting bees. Farmers should also minimise pesticide drift from the field to adjacent areas. Laws governing registration and use of plant protection products indirectly play a major role in the protection of pollinators. Trampling by people and livestock and tilling should be managed to conserve the nesting sites of soil-nesting species such as Heriades bees. KARI (the Kenya Agricultural Research Institute) is developing protocols for mass rearing of different species of solitary bees. Any successful results from this research will be freely communicated to the public. In addition, KARI is collaborating with other stakeholders to ensure in situ conservation and management of bees for pollination purposes. Much of the work of conserving native bees will be underpinned by raising public awareness of the importance of these species.

Legislation (National and International)

There is not yet any legislation in East Africa that explicitly addresses pollinators. However, there is scattered legislation for the protection of biodiversity particularly that covering environmental protection, protection of wildlife and heritage sites, protection of forests and natural resources such as water catchments. In addition, laws governing registration and use of plant protection products also indirectly play a major role in the protection of pollinators Such legislation, together with market-based mechanisms such as the Good Agricultural Practices (GAPs) codes and practices may help to protect bees albeit incidentally. At the international level, the Conservation on Biological Diversity (CBD) is spearheading strategies to enforce bee management for pollination purposes within the member countries, which include Kenya, Tanzania and Uganda. Farmers should lobby their governments to develop Integrated Pest Management policies that would protect bees and other insects of importance in agriculture.

References

1. Eardley CD, Gikungu M and Schwarz MP (2009) Bee conservation in Sub-Saharan Africa andMadagascar: diversity, status and threats. Apidologie, 40: 355–366.

2. Eardley CD and Urban R (2010). Catalogue of Afrotropical bees (Hymenoptera: Apoidea: Apiformes). Zootaxa, 2455: 1–548.

3. Michener CD (2007) The Bees of the world, the John Hopkins University Press, Baltimore and London , pp 913.

Editors

Théodore Munyuli, Busitema University - Uganda; Muo Kasina, Kenya Agricultural Research Institute (KARI) - Kenya; Juma Lossini, Tropical Pesticides Research Institute (TPRI) – Tanzania; John Mauremootoo, BioNET-INTERNATIONAL Secretariat – UK; Connal Eardley, Plant Protection Research Institute (PPRI) – South Africa.

Acknowledgements

We recognise the support from the Kenya Agricultural Research Institute (KARI), Tropical Pesticide Research Institute (TPRI)Tanzania and Busitema University (Faculty of Natural Resources and Environmental Sciences) - Eastern Uganda. This activity was undertaken as part of the BioNET-EAFRINET UVIMA Project (Taxonomy for Development in East Africa).

Contact

BioNET-EAFRINET regional coordinator: [email protected]