By Michael P Garrett
Research. A word that has several meanings. Depending on what side of academia you come from, the word research comes with completely different connotations. To an English professor, research could meaning rereading countless books or articles to further develop a thesis topic. To a journalist, research usually consists of gathering data and tracking down sources to provide their articles with more credibility. A scientist might see research in a completely different way as well.
To the average person, people equate research with the sciences. It is easy to formulate the idea of a person in a white lab coat bending over microscopes all day to find out the next big scientific breakthrough. But has the average person ever stopped to think, where do these scientists obtain all of these specimens? What exactly do scientists even do?
This was precisely the question I had when I was selected to join the Entomology department from the University of Kansas on a field research trip to Costa Rica. Dr. Andrew Short, along with a number of other lab assistants, traveled to Tapanti National Park in Costa Rica to collect different samples beetles to bring back for their research.
This article will explore the different methods experts, such as Dr. Short and his lab, took to obtain species of beetles and other insects in the cloud forests of Tapanti.
Flight Intercept Trap: Flight Intercept Traps, sometimes refereed to as FITs, are the only permanent traps set up by Dr. Short and his lab. They are difficult to set up for two main reasons. First, you have to find just the right spot to set them up, as you can imagine, this is no easy task in the middle of a cloud forest. Second, they’re extremely hard to set up just right.
Here are the steps to setting up a proper FIT:
1. Tie a screen up to two trees so it hangs perpendicular to the ground.
2. Place eight trays below the screen to catch insects as they fly into the screen and fall down.
3. Hang a plastic rain fly over the screen to protect the trap from storms.
The rain fly should be angled down hill to direct water away from the trap.
4. Tighten the screen to ensure it’s secure.
5. Use steaks to anchor down the screen. These can be made out of sticks found around the forest.
6. Stabilize pans so the water doesn’t tilt out.
7. Fill all of the pans with water and stabilize the pans one more time.
8. Add antifreeze to all eight of the pans that are already filled with water. This makes sure the water wont evaporate. The antifreeze also acts as a preservative so when the insects fall into the pans, their bodies will stay intact until collected.
That’s it. A perfectly set up FIT.
After 48 hours, you go back to the FIT and collect the insects that fell into the trap.
Emptying the FIT:
1. Pour the antifreeze through a fish net. The net will catch all the insects and the antifreeze will run into the pan so you can use it again.
2. Empty the contents of the fish net into a bag.
3. Pour alcohol into the bag. Pour the contents of the bag into a vial and take the vial back to examine.
Light Trap: The light trap is an interesting trap. It seems so simple, yet genius. In fact, most people set up “light traps” every summer evening when they turn on their front porch light. The point of the light trap is to turn on a light somewhere high on a hill at night so insects are attracted to the light. After it is set up, you can come back at night and look at all the different species of insects it attracted.
Here are the steps to setting up the light trap:
1. Hang a white sheet on a string using clothes pins to hold the sheet onto the string.
2. Place another white sheet below to catch insects that fall down. It also makes it easier to see if insects are on crawling around on the ground.
3. Hang a mercury vapor light infront of the sheet to attract insects.
4. Wait for night, then look at all the insects the light attracted.
Here are some of the insects Dr. Short’s lab found using this method:
River collecting: Dr. Short’s lab also conducted samples in the rivers around Tapanti National Park. The main river that runs through Tapanti is known as the Orosi River. Dr. Short, along with Monkia Springer and her students from the University of Costa Rica, used two types of sampling methods when collecting insects in the river.
The first method is called the Surber Sample. The Suber Sample is considered a quantitative method of sampling. The point is to calculate the contents of a certain area in the river.
1. Pick a spot in the river where all rocks and sediment fit into the bottom square without poking out. Since it is a quantitative sample, you only want specimens that fit into the bottom of the square. It is also important to make sure the current of the river is flowing into the bag attached to the square.
2. Sift through all of the rocks and sediment in the square. The insects disturbed will drift downstream and into the bag attached to the square.
3. Take the contents from the Surber Sample and place them in a Ziploc bag filled 1/3 of the way full with alcohol. Take the bag back to the lab and pick out the insects from the sample.
The other type of water sampling is a Multi-Habitat Search. This is a qualitative method of sampling. Rather than picking a spot and sampling what is in that area, you actively search the river to find whatever insects you’re looking for.
1. Take a net and disturb the sediment and rocks lying on the bottom of the river. A cloud of dust like water will emerge. Swipe the net through the dust to collect any insects that were under the rocks or sediment. Do this three or four times.
2. Take the contents of the net and place them into a tray.
3. Fill a vial with alcohol to preserve the insects you find. Next, use tweezers to grab the specimens out of the tray and place them in the alcohol vials.
Berlese funnels: The Berlese funnel is a method used to find beetles and other insects that reside in leaf litter from the forest floor.
1. Hang up funnels on a clothesline. Dr. Short’s lab hung up six.
2. Hang a light bulb over each of the funnels. The light will help dry out the soil and force the insects down into the whirl-paks full of alcohol.
3. Find leaf litter somewhere in the forest. It’s best to get leaves that look really old and rotten.
4. Take the leaf litter and put it into the sifter. Use the sifter to separate the large litter from the smaller leaf litter. As you shake the bag, dirt and insects will fall through the sifter and into the tied off bag at the bottom. Take the litter that falls through the sifter and empty it out into a pillow case or some sort of bag to take back to the Berlese funnels.
5. Fill each Berlese funnel with about one liter of leaf litter.
Make sure the litter is evened out
6. Attach a Whirl-Pak filled with alcohol at the bottom of the funnel. This will catch the insects and preserve them.
7. After the liter is distributed among all of the funnels, plug the lights in and turn them on. Let the funnels sit until the litter is completely dried up. Then detach the Whirl-Pak full of insects.
Berlese funnels complete. This process can be repeated as many times as you want. It’s a great way to collect insects from the forest floor.
Hand Collecting: This is a very similar method to the Multi-Habitat Search method used in the rivers. The point of hand collecting is to actively search for beetles or other insects by searching habitats frequented by whatever species you’re looking for.
Dr. Short’s lab focused on three habitats:
Lentic habitat (Marsh)
Lotic habitat (Stream)
Hygropetric habitat (Waterfall)
How to effectively hand collect:
1. Choose a habitat to search. Each habitat has different techniques to effectively collect insects. For the marshy habitats, slosh around in the vegetation to disrupt the beetles and make them surface.
2. Use a tea strainer to sift through the muddy water and capture the insects. It is helpful to use what is called an aspirator to collect beetles. Aspirators are a device that allows you to suck up insects through a tube. The insects go through the tube and into a vial where they can be kept until you are done searching a habitat.
The method for the stream habitat is pretty similar. The only difference is you need to make a circle of rocks in the stream. This creates a sort of pool so the insects don’t get washed down stream.
The second part is the same. Use the tea strainer to collect insects and place them in a vial filled with alcohol. Respirators are also very useful when working the streams.
Waterfall collecting is very similar as well. The only difference is you’re searching through moss, rocks and other things to find the insects rather than pools of water or streams.
One useful tip is to place leaf litter on a grate over a tray while you’re hand collecting. Beetles and other insects in the litter will fall through the grate and into the tray. You can collect these insects after you’re done checking a habitat.
You can also put moss in the trays to try and find insects.
All of these methods were used by Dr. Short and his lab to collect specimens. These insects collected will be what Dr. Short studies in his research at the University of Kansas.
This was but a small look into the scientific world and how scientists conduct research in the field. Hopefully some insight has been given to what research is and where all of the facts and data floating around scientific journals and encyclopedias come from.