Controlling predators in your BSFL breeding colony

Our experiences at Bobo Eco Farm
Edward Ssebbombo

Our work at Bobo Eco Farm has benefited a lot from other people who have generously shared knowledge / resources with us; we intend to do likewise through sharing experiences, views, and lessons learnt. Today we would like to share our experiences fighting predators in our BSFL breeding unit.

We raised our first successful BSF colony at the veranda of our apartment in Kampala. Actually the BSF breeding unit was kept at the veranda while the larvae rearing unit was stationed in one corner of the dining room! The idea was to develop & test a BSFL rearing unit that could be adopted by people in urban centres with limited spaces. We had noticed two opportunities in Kampala; foremost, Kampala Capital City Authority collects over 32,000 tons of garbage per month (only 40% of the total amount of waste generated in the city)! Secondly, the Kampala City Council Solid Waste Management Ordinance of 2000 states that the party that generates garbage is responsible for its final disposal. So, an additional by-law was being drafted that compels waste producers to pay a specific tax for their garbage. Therefore, individuals and institutions would easily buy-into the idea of recycling their waste, turn it into a valuable resource & make money from it other than spend money on it!

Breeding experiments were a success in Kampala and later at the farm, but along the way we experienced many challenges, and were quite valuable learning experiences. Predators were one of those; Lizards, rats, birds, spiders, and “munyeera”. We asked old folks for indigenous control methods, and I also reflected on my previous experiences as a bee keeper.
The focus was on measures that can help to keep them away NOT to kill them! Reason, they have a role to play in maintaining or sustaining the ecological balance. Lizards for example feed on houseflies, spiders & mosquitoes preventing them from turning into big outbreaks! Furthermore, some biological control methods are multi-purpose; you can use them to control pests at your farm and afterwards you use them for food, or even sell for money! Besides, use of toxic chemicals makes our farms unsafe for our kids and pets! So, now you will know what our tool box comprised.

Text Box: Lizards and a certain species of small black insects “munyeera” were our arch enemies. Being at the veranda meant our flies were exposed to rain in case heavy winds blew. So, during the night we would cover the whole unit under a mat and squeeze it against the wall. We however began noticing our colony reducing significantly, and wings of flies scattered around. One day, while removing the mats in the morning, I noticed a lizard running out of the fly cage; it happened during the subsequent days. We realised lizards ran from the main house into the BSF unit, and the mats provided them cover. Lesson: lizards thrive on food and cover! So, ensure the following to keep lizards under control.

Keep your BSF rearing facility clean, light, ópen’ and tidy. Avoid stuffing in too many items, or pushing items against walls so that you deny lizards a hiding place. Clutter helped lizards to finish our pilot cockroach colony at the farm! Furthermore, untidy environments favour proliferation of other insects which are food for lizards so, keep the prey out, predators will be out too!

Furthermore, it does seem lizards hate strong spicy scents or plants with strong scents such as onions. Some people talk about garlic, in our case we used spring onions. We planted them around the BSFL rearing unit. We have also made use of mint; you can pot them and hang them around the BSF house. Others hang onions in their house corners so that every turn lizards make they just bump into another repellent!

On the streets of Kampala you will normally bump into somebody flashing a small ‘book’ in their hands “ekitabo ky’emesse, ekitabo ky’emesse” selling a book with gum inside to trap rats. This traps lizards too!

Geese are a natural predator to lizards; keep a pair at your farm, lizards will have to relocate for safety elsewhere! As the geese proliferate, the farmer proliferates too – as you can also harvest them for a nutritious meal!

In addition to lizards we had a heavy infestation of rats at the farm. We got in two cats to control the rats. We however found that one of the cats in fact preferred lizards to rats. So, just keep a cat around your BSF rearing facility & lizards will be gone! What I’m not so sure of is whether the cat may not deep its hand into the larvae rearing unit!
Lizards have behaviour of normally lurking around or staying put for a few moments – eye to eye with you when you show-up! If you decide to handle it violently, just pick a stick, harass it away or hit on the head, it will drop dead instantly.

There are many insecticides on the market and can really kill lizards – if they inhale the toxic spray; but avoid that temptation as will also kill your BSF!
You need to learn how to detect lizards early enough before they multiply and cause havoc in your BSF breeding unit. One of the ways is looking for their droppings; their droppings are blackish with a white tip. You may also spot broken ‘egg-shells’ like the ones in the picture below. If you see these, then you need to employ some of the above measures to control them early enough before they multiply.

These are small black insects. When one lands on a prey, within minutes you will see a thousand gathering around it! They are small but effective. Left uncontrolled, they can take over or colonise a place and exterminate the previous occupants. They are normally invited by food crumbs or clutter. They are one of the commonest insects you will find anywhere in Uganda. They may move in a single file, or most commonly in track, and they normally exhibit this behaviour when moving between their bases – which may be a hole in the ground or a crevice or crack in the house. They also make a track when they get a prey. Otherwise, you will see them wondering all over the place lightly – each moving in their different directions, and fast; if you look closer you will notice as if it’s on a mission – scouting for a prey!

Twice, while still running our BSF pilot in Kampala, our colony suffered heavy attacks; one was almost taking over the pupation chamber, another one in the mating chamber. They would normally come in the night, and by morning the colony is in disarray. Covering the unit under the mat, and leaving dead flies around the breeding unit were the causative factors. I would say that if one went on a long trip for about two to three days, this may be enough time to find the whole colony finished! Unfortunately you can’t even use insecticides in this case because you must first do a ‘surgical’ operation of rescuing your BSF first, gathering the remnants, and repulse the invaders. After this, the old saying becomes your best strategy – prevention is better than cure!

We learnt the hard way! After narrowly surviving the second attack, we determined that these were our worst enemies. We started searching for a long-term solution. We went into the direction of re-designing our breeding unit to proof it from attack. During a conversation with one of my helpers pondering the new design, he pointed out cost escalation for the new design I was describing and he gave me a quick solution that I use up to today. In Ugandan shops (super markets, agro shops) there is a product called “Dudu dust”. You just sprinkle this around your BSF breeding unit or the whole facility. You can also just sprinkle it on the stands of your breeding unit, no insect will climb it. There is also one in form of a chalk which you can use to ‘write’ or put a line around the stands of your breeding unit. Insects can’t cross the line / writing. This is locally known as ‘koloboza’. Both the sprinkling and writing can last for a month or more
In my previous involvement as a bee keeper, we used to smear a thick line of oil or grease around the stands of the bee hive to control “munyeera”. This should also be used by farmers in this case.

All the above should be done in addition to keeping the area of the BSF breeding facility clean, clear and tidy!

During our early days of BSFL trials at the farm; I went on a trip for a few days, and on return the attendant to the BSF breeding facility reported to me that rats had eaten all the larvae! Rats! It is actually the first time we planted onions around the rearing facility. This also works for people cultivating sweet potatoes – rats are a major pest; just plant onions around the garden. Rats cannot put up with the strong scent of onions. It was a good solution because we also harvest some to spice our food! We also keep mint close as it also has a strong spicy scent.
This is the time we introduced cats to the farm. Depending on the design of your BSFL rearing unit, you can as well put barriers on the stands of your unit which rats cannot overcome.

There are also traps that you can use; many locally made and cheap. These are normally found in open markets which are common in rural areas. This is also effective in reducing the population of rats if used consistently.
In our experience another effective strategy we used was to clear the bush around the insect rearing facility. When rats are denied hideouts, they will migrate to other places that offer a better environment for them.

There are many types of toxic pellets on market to control rats; I would advise that you take extreme caution so you don’t reap un-intended consequences. Your poultry or any other may eat those pellets too. Kids are fond of picking up things, here and there, it’s better to keep poison out of your farm.
Oh yes, some people have talked about alcohol! If you produce wine on your farm, you can put some in a container that is accessible to rats and place in your BSFL rearing facility. They will get drunk & you will find them in the morning sleeping or staggering around!
We have also used ‘indocid’ to control rats at the farm. Indocid is a human drug normally prescribed for back pain. You just crash them in food & leave for the rats. Whichever eats will be gone!

As soon as they discover that you’re rearing some insects, birds will make visits to your rearing facility. Just a month ago, I found a tiny bird had built a nest inside the BSFL rearing facility. Quite strategic! We put chicken mesh around the facility to keep birds out, and even our turkeys.

We grew up our parents warning us against striking at this eight-legged creature – “it will blow at you and you will swell”, they warned. Spiders belong to the arachnid family. They normally trap other insects such as houseflies and mosquitoes for food. On a number of cases we found cobwebs lay within our breeding unit. If un-attended to, spiders can really impact on your colony.

Black soldier flies trapped in cobweb

Spiders are attracted to dark, un-disturbed, cluttered places with piles of things. As a control measure you need to keep your breeding facility clean and clear. Put down or destroy the cob webs whenever you find them as well as the egg sacs. If you consistently keep putting down cobwebs, spiders will completely turn away from your facility since they will be starving. Cobwebs are their way to trap food! It will also be more useful to clear bush around your facility so they are denied a suitable habitat near your work. As already mentioned, it would be better to avoid use of insecticides such as doom; they will also affect your BSF colony.

Once again, I encourage you to go for biological control measures to manage the problems because all these things add to the diversity and abundance of the ecosystem, thereby adding resiliency to it.