Category Archives: Pollination

Bees and Butterflies in the Pugu Hills, Tanzania

Dear All

I recently went hiking in the Pugu Hills which are near the port city of Dar es Salaam in Tanzania. These hills contain some precious fragments of forests that once covered most of the East African coastal areas. However, today only tiny patches of forest remain. These forests are home to a lot of different species that aren’t found anywhere else in the world including trees, butterflies and other insects.

Here are a few of the remarkable insects that I came across during the walk.

One of the first creatures that we spotted was this remarkable Hairstreak butterfly (Hemiolaus sp.). It flies fast and furiously along the forest trails – but only when it alights can you appreciate its delicate beauty. The elaborate tails on the right are actually a false head that serve to lure would-be predators away from the butterfly’s real head, thereby allowing it to escape. This is a common strategy in this family of butterflies that are known as the ‘blues and coppers’ or lycaenids (Lycaenidae).

Sapphire Butterfly (Hemiolaus sp.)

Hairstreak Butterfly (Hemiolaus sp.) Which is end is the real head?

 

A few minutes later a flash of copper whirled by and stopped to rest in a patch of flowers. This is one of the Scarlets (Axiocerses sp.) another of the interesting members of the lycaenid butterfly family. Here you can see it’s false head in place:

The Scarlet butterfly with it's false head intact.

The Scarlet butterfly with it’s false head intact.

 

And here is one that escaped a predator with the false head missing:

Hmmm... where did my tail go!?

Hmmm… where did my tail go!?

Even though the butterfly is now damaged, it survived the attack and can go on to mate and lay eggs and therefore contribute its genes to the next generation: this is what these amazing adaptations are all about – increasing the chances of survival and reproduction.

At the edges of the forest in the tall grass there were numerous Acraea butterflies basking in the sunshine:

Acraea butterfly sunning itself.

Acraea butterfly sunning itself.

A few minutes later I came across yet another lycaenid butterfly species, this one is known as ‘The Playboy’ (Deudorix sp.):

The gorgeous Playboy Butterfly

The gorgeous Playboy Butterfly

Flying elegantly through the forest were numerous swallowtails, which are large and showy butterflies, including this beautiful Eastern White Lady (Graphium sp.):

Graphium_philonoe-Pugu-LR1

 

Of course the bees were not to be outdone, and as the day grew hotter, they came out in large numbers to visit the different flowers in search of nectar and pollen. Most of the bees were visiting wildflowers at the edge of the forest and along the trails.

There were a lot of bees about, and sometimes it seemed like they needed some air-traffic control as they approached the flowers in droves!

Big bee first... little bee second. Prepare for landing!

Big bee first… little bee second. Prepare for landing!

 

More bee traffic!

More bee traffic!

 

At the forest edge there were lots of Macrogalea bees visiting various wildflowers. Macrogalae means ‘long tongue’, and the bee uses its long tongue to sip nectar from the flower:

Macrogalea bee

Macrogalea bee

 

The carpenter bees were hard at work too, especially on the flowering trees and shrubs in the forest:

Two carpenter bees (Xylocopa) feed side by side

Two carpenter bees (Xylocopa) feed side by side

After a wonderful day walking through the forest, there was yet one more special beauty waiting in the shadows. While this is not the most brightly coloured of butterflies, it is a coastal endemic and flies softly in the shaded groves of the forest: the enigmatic and delightful Spotted Sylph:

The Spotted Sylph

The Spotted Sylph

More from the wonderful world of insects soon!

 

Some bees in the bush…

Dear All

Many greetings, the rains over the last couple of months have brought forth some wonderful flowers out on the plains. Now with the mix of sunshine and abundant flowers, it is a fantastic time for the bees who are out and about in large numbers. Many other insects are also making hay while the sun shines, imbibing nectar, gathering pollen and reproducing while the conditions are good.

Insects and plants have an ancient and beautiful relationship that spans hundreds of millions of years of co-evolution. For every single species of plant, there are many different kinds of insects that live on, in, around and off it.

There is incredible diversity even around just a single species of wildflower as you can see from this series of photos on the humble wildflower Leucas, that is currently flowering on the plains south of Nairobi…

A speedy Amegilla bee who zipped like a maniac between the flowers sipping up the abundant nectar...

A speedy Amegilla bee who zipped like a maniac between the flowers sipping up the abundant nectar…

 

This particular bee was so efficient that it just grabbed the flowers for a second stuck its long tongue in and sucked out the nectar then moved on to the next one...

This particular bee was so efficient that it just grabbed the flowers for a second stuck its long tongue in and sucked out the nectar then moved on to the next one…

The Amegilla bees are fairly diverse and this other species was much more methodical in exploiting the flowers. Notice how it bends the flowers in a special way and rubs against the orange ‘blobs’? Those are the flowers’ anthers that bear pollen which is what the flower expects the bees to transfer between different plants…

Amegilla bee efficiently pollinating the Leucas flower...

Amegilla bee efficiently pollinating the Leucas flower…

 

Amegilla hard at work!

Amegilla hard at work!

 

There were some leafcutter bees working this patch of flowers too:

Leafcutter bee visiting the Leucas flower...

Leafcutter bee visiting the Leucas flower…

 

A few delicate lycaenid butterflies stopped by to sip some nectar (though it didn’t seem like they carried much pollen, so they are basically free-loaders!)

The Pea Blue butterfly has a drink of nectar

The Pea Blue butterfly has a drink of nectar

While I was watching for bees, this gorgeous emerald green chafer beetle flew by distracting me:

"Am I cool or what!?"

“Am I cool or what!?”

Later in the evening the carpenter bees came out to visit the flowers:

Carpenter bee on Leucas flower

Carpenter bee on Leucas flower

 

Of course, not everyone visiting the flowers was behaving themselves. There were  a number of stink bugs and groove-winged flower beetles shamelessly feeding off the flowers and buds:

Stinkbug (on the left) and groove-winged flower beetle  with head buried in blossom.

Stinkbug (on the left) and groove-winged flower beetle with head buried in blossom.

 

My ‘field assistants’ Barabara and Zaza took a break in shade as I was watching the bees…

Barabara and Zaza (hidden lying down)...

Barabara and Zaza (hidden lying down)…

 

What an amazing world all taking place on just ONE species of wildflower. Imagine if we could quantify all of the interactions between insects and flowers in just one patch of natural habitat for one day – I find all these interactions a source of wonder and inspiration…

 

What other mysterious creatures dwell here?

What other mysterious creatures dwell here?

 

More from the wonderful world of insects soon!

Bees sleeping…

Dear All

I recently participated in an expedition through parts of northwestern Kenya to look at different kinds of bees.

The first thing that surprises many people about bees is that there are lots of different kinds of bees – in fact close to 20,000 species have been described! The honeybee, which is familiar to almost everyone, is just one kind of bee (a single species called Apis mellifera).

One of my favourite bees in East Africa are the Amegilla bees. They are beautiful, fast-flying, hard-working creatures that zip about and fly with a characteristic high-pitched buzz that is most evident when the approach flowers. Amegilla are solitary bees. This is another surprising fact about bees: most species are solitary, with females building and caring for a nest on their own. Honeybees are social and live in colonies, as do a few other bees, but for the most part, the bees are loners.

Female solitary bees have their nests to go to at night or when they are not out feeding from flowers. However, males don’t have anywhere to go. They end up having to sleep on stems of plants, grasses being a favorite perch… In some species, such as Amegilla, the males will often gather at particular sleeping areas in the evening. These are often near a stream or edge of a wetland in a sheltered spot – sort of like a male bees’ version of the pub I guess…

We found this aggregation of Amegilla males sleeping at the edge of a swamp near Bogoria recently… They are really charming creatures…

 

Male Amegilla bees lined up in their ‘dormitory’ for the night…

More from the world of bugs soon!

Turkana Bees

Dear All

Greetings – have been travelling with limited email access (and time!). A few weeks ago I was in northern Kenya at the Turkana Basin Institute looking at bees.

A yellow-flowered legume, Crotolaria, was blooming in one site near the river and it was covered in some of the most amazing bees… Here are a few of them.

We started looking for bees early in the morning. In a sheltered area in a glade I found these beautiful orange Lipotriches bees collecting pollen from Cenchrus grasses. Most bees are solitary and gather pollen from plants to provision a nest where they lay eggs. This is what the Lipotriches were doing.

A pair of Lipotriches bees foraging on pollen from Cenchrus grass

 

The most striking bee we found was this Carpenter Bee (Xylocopa sp.) that had the most incredible bright blue eyes! It flew around quite aggressively occasionally chasing off other Carpenter Bees that ventured too close to its patch of flowers.

Blue-eyed Carpenter Bee!

 

The most common bees visiting the flowers were various species of Leafcutter Bees (Megachilidae). These are bees that cut circles from leaves and use them to construct their nests by joining them up and lining a tube. They are also among the most elegant and beautiful of bees… They also fly very fast and zip about nervously from flower to flower so I had to be both patient and fast so as to capture some photos of them.

A Leafcutter Bee approaching the flowers

 

There were several different kinds of Leafcutter Bees around, including this large grey species:

Leafcutter Bee - note the yellow underside of the abdomen - that's where these bees carry pollen.

 

Another smaller Leafcutter Bee species

 

Leafcutter Bees are good at "tripping" flowers - bending them down to get more nectar out...

 

There were hundreds of bees flying about at the same time. Some of the bees chased each other away, but some of them were happy to share the flowers…

Leafcutter Bee (above) and Macrogalea bee (below) feeding near each other.

Feeding from flowers lower down was this interesting solitary bee species in the Halictidae family… beautiful with its black-and-white stripes…

A Halictid Bee weaving about the Crotolaria flowers.

 

More from the world of bugs soon!

 

 

Coriander (Cilantro) Pollinators…

Greetings from Turkana in Northern Kenya. I recently visited one of the farms that I work with up here and was very pleased to find the coriander (cilantro) flowering. This plant is a common and delicious herb that is widely used in the cuisines of many different parts of the world…

Coriander flowers close-up

Coriander flowers close-up

Many of us are aware of the role played by pollinators in producing fruits and other crops like beans, tomatoes, etc. However, even many of the spices that we grow are dependent on pollinators – and without them would not produce the seeds that are the basis of a valuable trade and make the food we eat much tastier and more nutritious!

The flowers of the coriander plant (called cilantro in America) are open and lay in flat heads called umbels. This means that they can be accessed by a wide range of pollinator species. Here are some of the insects that we found visiting and pollinating the cilantro flowers in Turkana.

A lycaenid butterfly and a cuckoo-wasp at the coriander flowers

A lycaenid butterfly and a cuckoo-wasp at the coriander flowers

The lycaenids are tiny butterflies, many of which are common in the drylands of Kenya. They can often be found visiting flowers where they sip nectar and check each other out…

Two lycaenid butterflies enjoying the cilantro flowers

Two lycaenid butterflies enjoying the cilantro flowers

Many different wasps were visiting the flowers. The Cuckoo Wasp was among the most striking with its bright green iridescent sheen…

Beautiful Cuckoo Wasp

Beautiful Cuckoo Wasp

Cuckoo wasps are named after their behaviour where (like the cuckoo birds) they lay their eggs in other wasps’ nests – they are parasites.

Of course the bees were among the most common and efficient pollinators visitors to the coriander flowers…

Braunsapis bee at the coriander flowers

Braunsapis bee at the coriander flowers

The Braunsapis bees were the most common visitors to the flowers among the bees. They moved about a lot and we found them carrying lots of pollen too.

Happy Braunsapis busy on the flowers

Happy Braunsapis busy on the flowers

A number of tiny Stingless Bees were also active – collecting pollen and nectar…

Stingless Bee at work...

Stingless Bee at work...

All the hard work by the pollinators produces these beautiful seeds that we can flavour our food with!

Yummy coriander seeds thanks to the pollinators

Yummy coriander seeds thanks to the pollinators

More from the world of insects soon!

Honeybee + sunflower

Dear All
Greetings – just back in Kenya after various travels. There is a sunflower on the breakfast table and I watched a honeybee visited it this morning in the dreamy African sunshine…

Sunflower in morning light

Sunflower in morning light

Honeybees love sunflowers!

Honeybees love sunflowers!

The honeybee was after pollen – here is a close up of the anthers:

Anthers - the part of the flower that bear pollen

Anthers - the part of the flower that bear pollen

The honeybee lifts itself into the air and hovers, gently combing the pollen from it’s body into the pollen baskets on it’s legs.

Honeybee combing pollen into it's pollen baskets while hovering.

Honeybee combing pollen into it's pollen baskets while hovering.

Without honeybees, the sunflowers would not be well pollinated and would not produce the sunflower seeds that are made into oil and many other useful and delicious things. The honeybees on the sunflowers are both beautiful to watch and also to know that they are making the sunflower seeds happen through pollination.

The honeybees collect the pollen for their own use. They feed it to their larvae, which helps them grow into healthy strong bees. The sunflower produces lots of pollen, and the honeybees spill it and rub it around as they move about the flower. This results in pollination. Both honeybees and sunflowers benefit from this arrangement. A truly balanced partnership (or love affair!) from Nature.

More from the world of bugs soon!

Desert filled with bees

A recent rainstorm has brought out the flowers in the desert of northern Kenya where I am currently based at the Turkana Basin Institute (TBI). I am here teaching an ecology module for the Turkana Basin Field School. A single rainstorm that fell a few weeks ago has also brought out a large number of insects. Like many of the plants, the insects are active and taking opportunity of the greenery to forage and breed. And like the plants they are all under intense pressure to complete their life-cycles. For insects this often involves several stages as eggs, larvae, pupae and finally adults.

Deserts and drylands are often mistakenly thought to be places of low diversity. However, they are rich in insect life, but most of this is hidden away awaiting the brief periods of flowering. As this time is now upon us, it has been very exciting for the students to glimpse some of the incredible bee diversity in this habitat. One of the groups of insects that are more diverse in drylands, especially in Africa, are the bees. These are wild bee species. Many people are surprised to learn that there are more than just honeybees. Bee diversity in this area is largely unexplored and no doubt many exciting new species and biology remains to be discovered.

A tiny bee, Nomioides, visiting a Tribulus flower at TBI

We started out watching and collecting bees on the Indigofera spinosa bushes within the TBI compound. A number of bees have been frantically visiting the tiny pink flowers. The students have collected several different bee species on the Indigofera. These include some large leafcutter bees who carry pollen on their bellies, which turns them bright yellow. Another common bee visiting the flower was a Pseudapis. Also visiting the flowers was a striking parasitic cuckoo bee species (Coelioxys) that is a brood parasite of the leafcutter bees. Just like the cuckoo bird, it lays its eggs in the nests made by the hardworking leafcutter bees!

Pseudapis - one of the most efficient pollinators of the Indigofera bushes

Leafcutter bee with its belly covered in pollen!

Cuckoo Bee (Coelioxys) visiting the Indigofera flowers.

We then travelled to a site in the open desert plains where a carpet of miniature flowers pressed close to the ground was busy with bee activity.

Students search for bees on the open semi-desert plains

Here we found several different bees that we hadn’t seen nearer TBI. These included a beautiful halictid or sweat bee with a bright orange abdomen.

Tiny, gorgeous halictid Nomiine bee

We also spent time catching parasitic wasps and bees that were tiny. These are so tiny that we had to use small bags and slip them quickly over the bees as they were foraging, as they could wriggle through the holes in the nets! The students worked hard and learnt a lot about bee diversity and how much work it is to study them!

Students hard at work looking for tiny bees and wasps

Student Hui poised ready to catch one of the zippy bees...

The students also collected data on visitation rates to flowers on the Indigofera bushes. This species is really important as it is the main browse for goats and camels which are the livestock species that people depend on in the drylands of Turkana. We found that solitary wild bee species are both the most abundant and the most efficient pollinators as they carry pollen between many different individual plants resulting in effective cross-pollination. The Indigofera bushes establish new plants from the seeds that only come about as a result of pollination by the wild bee species. So the bees feed the goats and camels indirectly!

Camel browsing on Indigofera from seeds made by bees

More from the world of bees and bugs soon.

To learn more about the Turkana Basin Institute, please visit their website:

http://www.turkanabasin.org/

Leaf-cutter bees in action!

Hello! While watching the eggplant flowers for pollinators in Turkana I noticed that some of the leaves of several nearby bell-pepper plants had neat circular pieces cut out from them…

Who is responsible for these missing circles?

Who is responsible for these missing circles?

I sat down to watch the plants, suspecting that the perpetrator would be back soon. A few minutes later an fervent buzzing zipped up to the plants and settled on one of the leaves. It was a leaf-cutter bee!

Leaf-cutter bee sinks it teeth into a leaf

Leaf-cutter bee sinks it teeth into a leaf

The bee works rapidly to cut through the leaf in a near-perfect circle…

Leaf-cutter bee rapidly chews the leaf off

Leaf-cutter bee rapidly chews the leaf off

Then the bee takes off for its nest with the piece of the leaf held under it. It will use this to line the walls of the tubular next that it constructs for its larva. As these bees are also very good and efficient pollinators, they are welcome to use some of the crops’ leaves for their nests.

Leaf-cutter bee carries off the leaf to its nest!

Leaf-cutter bee carries off the leaf to its nest!

More from the world of bugs soon. Thanks to everyone for the kind comments!

Buzz! Buzz! Bees make eggplants…

Dear All

Many greetings. I have been up in the hot and dusty reaches of Turkana in northern Kenya. Most people only hear about this region as a place of drought and suffering. Turkana is also a beautiful, biodiversity-rich and potentially productive place…

Field of eggplant and Doum Palms in Turkana

Field of eggplant and Doum Palms in Turkana

I recently visited a pilot farming project in a remote area south of the Turkwel River. This is where the Turkana Basin Institute has been established through the efforts of Dr Leakey and Stony Brook University. Ikal Angelei is an amazing young woman who is involved in many different things related to the environment, human rights and development in the region. Ikal is working with a local women’s group using simple and sustainable irrigation to grow and produce food.

Ikal and freshly picked eggplants from the pilot farm

Ikal and freshly picked eggplants from the pilot farm

One of the crops grown up here is the eggplant or aubergine (Solanum melongena). Eggplants have beautiful pale-purple flowers with fused yellow anthers…

Eggplant is an interesting species in that the flowers require a very special kind of pollination in order to set fruit and produce a yield. It’s called buzz pollination and this short video tells you more about it:

[kml_flashembed movie="http://www.youtube.com/v/vYcMQ2G1R1I" width="425" height="350" wmode="transparent" /]

There were several different wild bee species visiting and pollinating the flowers. Here are some photos of them:

Solitary wild bee grapples with an eggplant flower

Solitary wild bee grapples with an eggplant flower

Wild Nomia bee bites the flower to 'buzz' the flower and release pollen

Wild Nomia bee bites the flower to 'buzz' the flower and release pollen

While most of the bees visiting the flowers were working hard to release the pollen, a few tiny stingless bees were ‘stealing’ pollen where it had been spilled by the efforts of larger bees. It does seem that even in nature there’s always someone ready to take advantage of others’ hard work!

Stingless bee on an eggplant flower - what is it not doing right?

Stingless bee on an eggplant flower - what is it not doing right?

Here are some photos showing the stingless bees taking advantage:

Nomia and Stingless bees come face to face!

Nomia and Stingless bees come face to face!

Macrogalea bee and a stingless bee lurking...

Macrogalea bee and a stingless bee lurking...

Thanks to the hard work of the bees and women up here in the ‘desert’ there are beautiful eggplants to harvest!

Healthy, nutritious eggplant thanks to the wild bees!

Healthy, nutritious eggplant thanks to the wild bees!

More from the world of bugs soon!

Bees make Raspberries!

Dear All

A few days ago I visited a friend of mine who runs a farm on the outskirts of Nairobi. Su Kahumbu is an organic farmer who does amazing work with farmers across Kenya promoting sustainable agriculture and innovation…

Farmer Su Kahumbu with her raspberry bushes

Farmer Su Kahumbu with her raspberry bushes

One of the crops growing at her beautiful model farm are raspberries.

These delicious fruits are one of my favourite desserts… And of course in order to have raspberries on the table you need to have raspberry bushes. The raspberry bushes have flowers that need to be pollinated in order for the beautiful and yummy fruit to develop…

Raspberry flowers are composite flowers – which means that they are actually made up of many tiny individual flowers all joined together.

Freshly opened raspberry flower

Freshly opened raspberry flower

In order for a flower to set fruit, it needs to be pollinated. On Su’s farm these free services are provided to her raspberry bushes by several different kinds of bees. One of the most common pollinators is the honeybee.

A honeybee grapples with a raspberry flower

A honeybee grapples with a raspberry flower

The honeybees move swiftly between the flowers and visit in large numbers.

Honeybees drink nectar and gather pollen at the flowers

Honeybees drink nectar and gather pollen at the flowers

As these are composite flowers, every single tiny individual flower, called a floret, needs to be visited and gently dusted with pollen by a bee. Otherwise there will be no fruits produced.

Recently pollinated young raspberry fruits

Recently pollinated young raspberry fruits

Honeybees are not the only bees visiting the flowers. There are also some wild solitary bees. These are even more efficient in some cases as they spend longer times on the flowers and manipulate them more thoroughly. The quality, shape, flavour and size of the raspberry fruit are all directly tied to the efficiency of the pollinators. Too little pollen and the fruit is pale, small and not very sweet. It takes many visits by many bees to make a fruit round and sweet..

Solitary wild bee on raspberry flower

Solitary wild bee on raspberry flower

It is the actions of all these bees who make the delicious raspberries happen!

Yummy raspberry thanks to the hard-working bees!

Yummy raspberry thanks to the hard-working bees!

Please think of the bees that put the food on your table next time you enjoy some raspberries for breakfast or dessert. More from the wonderful world of insects soon!