With the lead of MC Analisa, we finally set off to the Student Farms to set up tachnid fly traps! Before venturing off to our journey, Louie and Mia showed the class ways to effectively catch all those tachnid flies for our experiments. Louie showed that once we capture our insects in our insect nets, we can reach in with our containers, slowly slide our containers out, and then quickly put the lids on to prevent the insects from coming out. On the other hand, Mia suggests that we concentrate the flies inside the net into the deep end and then inverting the net to deposit the flies into the container. Either method works great depending on whichever one you’re more comfortable doing! After some practice, Louie claims that, “We’ll have some experienced fly wranglers at the end”!
Luckily for us, we were blessed to not have a single drop of rain come down and we were able set malaise traps to capture Lespesia tachnid flies under dry conditions. However with all the raining accumulated these past few days, the soil is very muddy and we had to stay on the main paths while trenching through the Student Farm because extra compaction is not so great for the edible crops grown here. Last week, we found many Spodoptera exigua caterpillars in the alfalfa field and decided to try our luck in catching some tachnid flies here this Friday. Once we reached to the alfalfa field, we grouped up and discussed where we were going to put our fly traps and decided to set three traps along the alfalfa field and set the rest of the fly traps in other areas inside the Student Farm to increase our sample size and test other areas if there could potentially be more tachnid flies present.
Before splitting into small groups, we learned to correctly set up the malaise fly traps and it was very similar to setting up camping tents. We included black, shiny balloons inside to attract our flies because they are attracted to black, shiny surfaces and placed a bottle on the top to capture them. We discussed that it may be better to leave the bottle cap on to trap more flies however it may collect rainwater in the chance that it rains in the field. However, we’re going to have volunteers to regularly check the traps and collect the flies daily!
For tips on extracting these flies, Louie states that the easiest way to capture flies is to connect two bottles and then invert the bottles and then disconnect them to capture the flies. This method can effectively collect our flies while preventing them from escaping because flies have a natural instinct to fly upwards.
Although we are set capturing tachnid flies in the field, some students also ventured through the alfalfa field with insect nets to capture some more Spodoptera exigua caterpillars. While capturing some spods, Riley actually found a rad spider egg sac inside his insect net! We opened it up and found hundreds of eggs with some already hatched. In fact, as Mia says this, the eggs “look like popcorn”! We discussed and thought that it may be possible that a spider was in the net during storage for some time and made a little home for the young ones. As far as which spider you may ask? We’re still unsure but this was a cool find in the field!
After collecting our spods and setting up our fly traps, we head back into the classroom and we discussed that we would set up fly cages to house our flies, identify the flies we found in the field, and set up containers with artificial meal for the spods we also found in the field. However, we needed extra materials execute these tasks such as the microsope to identify for Lespesia tachnid flies so a handful of students joined Louie to grab these materials from the lab. After getting all the materials, we split into 3 groups for each task. While building the fly cages, we mixed honey with water to create diluted honey as a food source for the flies to consume during their time in the fly cages and used cotton pieces for the diluted honey to diffuse out slowly and prevent them from drying out too quickly. In the FLY team, we identified used a microscope to look for some key features of Lespesia tachnid flies in all the flies we captured in the field this Friday. We managed to find one tachnid fly however it was not the Lespesia tachnid fly we were looking for. This is because the tachnid fly we found has more pointed wings compared the Lespesia tachnid. But we didn’t let this bring our hopes down! Hopefully, we will get to find more Lespesia tachnid flies in our malaise fly traps throughout this upcoming week.
On the other side of the classroom, we also cut artificial meal into little cubes and placed them into petri dishes and small containers for each of the Spodoptera exigua caterpillars we found in the Student Farm. We decided to place these caterpillars into petri dishes with holes because it was hard to find them in the plastic quart containers that we used on our previous batch of spods we found in the field.
As for the upcoming Tuesday when we meet, we are likely to discuss about the protocols for performing our experiments and start mass-producing striped landing paper for our tachnid flies. Because the weather forecast states that there are likely to be high winds on Wednesday, we may have a crew to check up the traps and take them down if necessary. But for the time being, we will need to keep a close eye on the weather forecast and monitor how many tachnid flies we’ll catch and identify over the weekend with the help of FLY team and check-up volunteers. After collecting these flies, we will be putting them in the fly cages labeled “Unknown” and place all the Lespesia tachnid flies in the other fly cage once we officially identify the flies “Unknown” fly cage. Until then, we will be progressing through our project one fly at a time!