Dear Beetlers,
Come to Science Uncovered this Friday 28th September to hear more about this:
We have returned safe and well from our recent fieldwork trip to Tanzania (we are into our second year of collecting!) and really want to share with you some of the techniques employed in the field. This trip was undertaken in the months of July and August - the dry season, where ordinarily there is not much beetle activity; however, one of the aims of this series of collecting trips is to map Tanzania's beetle and butterfly and moth fauna through all of the seasons. Eventually we will have a really useful data set from many (and remote) localities; and hopefully this will yield some very interesting new species...but until we get everything identified (we are still identifying material from 2010 - there's soooo much of it!) here is how we found our specimens in the first place...
Given we were heading to some really remote localities it was really important to inform local officials and indeed local people who we were and why this pair of crazy western 'researchers' had just appeared from nowhere. Here is our 4x4 vehicle with its very official notice!
U Tafiti is 'research' in Swahili; 'wadudu' is insect! So we were entitled 'U Tafiti wawadudu'!
Here is HT having quite a giggle with the Mama and farmer at Mount Hanang where we camped (Tanzania's fourth highest mountain at 3417m)
Once we had set up camp after a five hour drive from the city of Arusha; it was time to um, relax!
The beautiful Mount Hanang in the background.
HT and some cows; overseeing unpacking proceedings!
But, whilst some of us lounge about taking it easy, others are hard at work keeping the camp in order...
BG working hard whilst HT 'relaxes'! This is our 'science table' where all the processing of specimens: labelling, cleaning, filling up tubes with IMS happens.
And so into the field. Here at Mount Hanang there is diverse habitats: mid altitude grassland, farmed countryside, ericaceous forest and sub-montane and montane forest all a happy hunting ground for the intrepid entomologist...
HT, our local guide Isaiah and Jembe our Masai guide all erecting a butterfly trap on the forest edge at Hanang. This will be elevated high up in to the canopy and baited with some delicious rotting fruit.
Whilst HT was busy butterfly trapping I was off in another direction beating for beetles!
BG, our camp expert Saleem and Jembe all looking for SBJs (small brown jobs, such as Phalacrids, Shining Flower Beetles) and weevils by beating vegetation with a big stick onto a big umbrella-like white sheet!
Winkler Traps
Then it was into the forest edge to collect some leaf litter for sieving (again SBJs live in leaf litter, we are hoping to find things like fungus beetles (Lathridiidae) and Pselaphinae, and all manner of Cucujoidea)!
And the prize for the most boring photo...
Here's HT and Jembe sorting through leaf litter with a series of sieves
As most creatures that live in leaf litter are small and secretive there is another very effective method we use to collect them by, which is known as the Winkler trap! Once we have sieved the litter to remove all the big stuff the remaining topsoil and litter is placed inside mesh bags within the cotton bag and basically hung up to dry. Eventually the small organisms will start moving about and head to the bottom of the trap where they fall into a waiting pot of IMS.
Me with my Winkler! A very cold early morning at Mount Hanang!
We took samples of leaf litter at all three sites we collected from. The final site at Hasama Forest in Mbulu district was again at high altitude (c.2000m); as far as we know the last person to collect in this area was Kielland in 1990 and he was looking for butterflies...
Sieving litter for Winkler traps at Hasama forest, Mbulu. It was soo cold and windy that the only way to do it was to seek refuge by the truck!
Dung Traps
We can't have a blog without mentioning poo it would seem so, onto dung trapping! We were very lucky at Mount Hanang to have the employ of a team of able and willing young entomologists who worked very hard searching for dung beetles (so we didnt have to!) and were amply rewarded with 500 Tanzania shillings and a packet of sweeties! Our 'snacky time' was around 5pm and the children soon learned that the office would be open once the hard fieldworkers had taken off their boots and had time for a G&T before supper (very civilised!). Here's HT 'negotiating' prices with the children.
'Snacky time' at Hasama Forest! Of course a freshly pressed newspaper was always made available!
Driving a hard bargain! Our terms: one full tube (no padding with extra dung) and no repetition for 500 Shillings and a packet of jellies!
Team dung beetle! (I'm the one on the left...).
As our dung beetle workers would never reveal their sources, (very good business!) we did employ other methods. The classic dung pitfal trap where little pre-made knapsacks of dung (this time buffalo!) are suspended above pitfal traps work really well. These were placed every one hundred meters into and along the forest at Hanang.
HT and Isaiah preparing dung pitfal traps
On to Longido, about 50 km from the Tanzanian / Kenyan border to a very different habitat: the bush! Very very dry and surrounded by Masai, goats and Acacia trees...we had to work very hard to find beetles here!
Longido bush setting traps: dung knapsack - tick! Soap-laced water for pitfall traps - tick! This entomologist is good to go!
Sometimes less sophisticated methods can also be employed given one has the time and the inclination to look hard enough...
Yes, I am literally grubbing about in fresh buffalo dung; here I found some interesting Hydrophilid beetles especially adapted to living in poo!
Water Beetles
That takes us on nicely to collecting for water beetles. Whilst having a dreamy ride through the Eastern Rift mountains on our way to Mbulu, HT exclaims rather excitedly 'Stop the truck! Water!' I was less enthusiastic and stayed in the truck observing from a safe distance whilst HT sank up to his knees in a stagnant no doubt disease ridden puddle of water in the pursuit of water beetles and their ilk (Dytiscidae). And what better way to catch them than with a household sieve!
NOT allowed back in the truck!
Once at Longido, our Masia guide (we are not permitted to enter any forest reserve without a local guide) promised there was water in the mountains. After an arduous trek to approx 2500m, and at times loosing what path there was, not to mention the searing heat, we eventually came to a mountain stream...
Here we found not only some curious looking Dytiscids (predacious diving beetles) but also some whirligig beetles (Gyrinidae), leeches (yuk!) and a fresh water crab!
Water beetles are really hard to catch, being predacious they are really fast swimmers and also the bigger ones can give you a nasty nip if you're not careful; we found some big ones...
SLAM and Malaise trapping
Trapping using nets is the most common method but can often times be difficult in challenging terrain, not to mention remote environments where local people are overtly curious about what on earth you are up to! In Longido, where Masai children would appear as if by magic (We hold them entirely responsible for our missing pitfal traps!) we decided that the SLAM trap was too enticing for curious minds so we erected it as high up in the canopy as we could! This type of trap is very versatile as it can be erected anywhere but is especially good for wood piles where emerging beetles will fly into the net and become trapped.
Hoisting the trap with BG and Saleem
The entomologists demonstrate their good work!
Malaise traps are more precise in where they should be placed. Ideally they should be in the way of an insect flight path so that insects fly into the net, instinctually fly upwards and just like the SLAM trap, become, um, trapped!
The very important job of holding a piece of string; erecting the Malaise trap, Mount Hanag
But oh no! It's all gone wrong - in an ironic twist of fate it is the entomologists that have become trapped...
Finally to end on a 'lighter note' we must mention light trapping! Light trapping might be commonly employed for trapping butterflies and moths but it is actually very effective for catching beetles too. So, each night at dusk we would start up the generator and the mercury vapour light would work its magic! One night at the Longido camp an unexpected downpour somehow broke the light and so we lost a nights trapping; at Hasama forest the winds were so high that the light was smashed; another nights trapping lost. But, on a good night, it's possible to stay up for as long as you can, say until 3pm gradually picking off the insects that come to the light. At longido I found a prize Carabid, an Anthia, or more commonly known as a Domino beetle, that was more attracted to the sausage flies than the light!
The downpour at Longido; luckily we had enough tarpaulins but failed to secure the storm flaps on one of the tens = wet sleeping bag!
The entomologist (still apparently in her pyjama bottoms), demonstrates the light trap!
And we leave you for now with a beautiful view!
Next time the hardships and hiccups of fieldwork; and after that, fashion, fieldwork and friviolity...watch this space!
So the intrepid entomologists say farewell; and hope that you will join us and our wonderful colleagues on Friday night at Science Uncovered to hear more about collecting in the field, all over the world! http://www.nhm.ac.uk/visit-us/whats-on/after-hours/science-uncovered/index.html