All Island Ant Survey

Every CAST tour, that is, every six months, a survey is conducted called the All Island Ant Survey. The purpose of the study is to find out where the infestation of Yellow Crazy Ants is located. Perhaps the infestation area has grown, gotten smaller, shifted, a random spot popped up outside the infestation area, or it has remained the same. Another reason the survey is completed is to find out if there is an infestation of a new species of ant. And the last reason for the survey is to get an idea of all of the ant species on the island and their placement and numbers. This will help us to determine the kind of response the other ant species may have with the future removal of the Yellow Crazy Ant Species.

Now the island is set up with a grid system. A number and letter grid system, to be exact. Every 50 meters there is a flag to indicate that spot. If you were to be at one of these flagged locations, you could look at the flag and see that it is labeled with its grid number. For instance, this is 32G. If you were to walk South, 50 meters away from its location, you would find 32H. If you kept walking, the next flag you would hit would be 32I. Now, if you took a turn to the east, you would find a flag 50 meters away that was labeled 33I. You get how this works? Anyway, the whole point of this grid thing is to tell you that during the All Island Ant Survey, all of these points will be part of the data collection process. And there are 1,053 50 meter points on this island.

The day prior to starting the survey, we wrap aluminum foil around 15ml centrifuge tubes. The foil is there to keep the inside of the tube cool so that ants will be more likely to enter a normal temperature tube as opposed to a sauna tube. We foiled about 80-100 tubes per person, or 400-500 total tubes the first day. We also fill out our notebooks. We have a spot for the 50 meter point name, the time we put the tube down, the time we pick up the tube, and, again the 50 meter point name, but this time in permanent marker. We cut between the labels so they are tear-able. These will be going in the tube with the Spam and ants.

The night before the survey, we have a Spam party. Katrina is the Spam cutter. She cuts the Spam into little cubes. The rest of us, me with my fondue fork, put the Spam into the tubes. We close the tubes immediately so the Spam will not dry out and will be as fresh and smelly as it can be in the morning. And I do mean morning. I get up, grab my 80-100 foil wrapped tubes filled with Spam, and am at my first 50 meter point at six-thirty. I open a tube, make sure there is in fact Spam in it, tear the appropriate label from my notebook, put it in the tube, then the tube gets put by the flag; I write down the time and move to my next point.

Once I have been to all of my points, I head back to my first one. For this survey, we wait two hours to pick up the tubes. So, I put my first one down at six-thirty, so I can pick up at eight-thirty. There is a twenty minute buffer if I am late. Good thing, because if I was over the two hour mark, and past the twenty minute mark for picking up the tube, I would have to resurvey the points I overshot the next day. Good thing I was never late getting a tube! When I do pick up the tube, I approach slowly and quietly. I do not want to scare the ants. Then I grab the tube and close the lid, being careful not to smash any ants in the cap. Once I have picked up all my tubes, I count them to make sure I have not forgotten one. Before I head back to camp, I make sure I don’t have any Yellow Crazy Ant hitchhikers. We don’t want to be providing them rides to make a larger infestation area, especially in camp.

Once at camp, we take off all the foil wrapping, but doing it gently so they can be reused. Then we check to make sure we have ants. We make piles. A “Yes ants in tube” pile and an “empty tube” pile. Our empty tubes have to be double checked by one other person just to make sure.

For preliminary data, we document the tubes that are empty “none”, the tubes with other ant species “OAS”, and the tubes with Yellow Crazy Ants, “YCA.” Then the tubes get put into Ziploc bags according to their transect numbers. For example, all the tubes that are collected along the 32 line get put into the “All Island Ant Survey, Transect 32, July 14, 2014” bag. Then all bags are put into the freezer for 48 hours. This will most nicely kill the ants. It has to be done pretty soon or else they could start eating each other. The first day, we did 25 of the 64 transect lines of the island. The rest of the day was filled with putting the recycled foil on new tubes and, that night, another Spam party. The next day we did 27 of the remaining 39 transects. The last day, we finished the last 12. That was a lot of walking. But we did get to see a lot of the island that way. Lots of new things to discover! My second day I had a bunch of Short Eared Owls following me! My first day, I found a nasty centipede stealing a Spam cube from one of my tubes.

Once the 48 hour freeze time was complete, we were free to start Ant ID. Of all the 1053 tubes we collected, 736 tubes contained ants.

Some reasons there were no ants in some tubes could be because the point was in the middle of a concrete parking lot or the tubes were close to the ocean and was too wet for the ants liking. But still, 736 tubes is a lot of ants to ID. The first step is to label the tubes. That kind of got to be my job. I use the label inside the tubes that were torn from notebooks to tell me what to label the outside of the tube. I didn’t do them all at once. I just stayed ahead of people grabbing them to ID the ants inside.

At first, we would do Ant ID two people at a time as the Ant ID table held two chairs and two microscopes. We first pull out the ants from the tube using paint brushes or probes. Then we spread them out and count them.

Some of the ant species cooperate. Some don’t. Some separated nicely. Some stick to your probe and won’t come off. Some like to cuddle and mess up our count. Some big ants like to hide smaller species of ants. Some are imbedded into the Spam. Some like to be ripped apart unless you are extremely gentle. Some are squashed in the cap and have to be peeled off. I guess what I am trying to say is that they are not always helpful. We do what we have to do to separate the ants from each other and lay them out in a tray. Then we count them. Then it is time for the microscope. We use a key to help us make IDs. Like one step is, “How many antenna club segments are present? If 3, go to step 6, if 2, go to step 20.” It doesn’t say exactly that, I made that up, but it is very similar. When we follow the steps, it gets us to the right species.

Then we write the information down. The station (the 50 meter point), the observer (who counted and IDed it), the species of ant, and the number of ants. Then the tray gets put aside until the other person can double check it. They recount and re-key out the species of ants.

Once everything is confirmed, the information can go into the official Ant ID notebook to be used to enter the data into the computer.

I was noticing that we were having a hard time coming up with the same number of ants when we double checked. It could be counted four times and four different numbers of ants would be counted. Some of the tubes contained hundreds of ants and some of them are pretty tiny. It is hard to count that many. Then I had an idea. What if we arranged them neatly? I tried it without saying anything. I put my next tube’s ants in rows of ten. When it came time for the other person to double check, they were able to count them so fast and they came up with the same number as me! It saved so much time. I don’t think I actually said anything about my idea, the others just did the same thing after seeing how easy and fast it was. Like this picture, there are 774 Tapinoma melenocephalum in this tray. Could you imagine them just scattered about? What would be the odds that two people would come up with the same number the first time around? In this method, the second counter only has to verify that each row does, in fact, contain ten and then count the number of lines. Piece of cake, accurate, and fast.

Then another thing came to mind. Most of the time is spent doing Ant ID is counting all the ants, not IDing them. So why do we need to limit the man power by the number of microscopes? The answer is, we don’t. I suggested that we can all work on Ant ID at the same time.

Making it five people instead of two. This sped up the process by an amazing amount. Some sat at the “Ant ID” table and some at the kitchen table counting out the ants. Then, when it was time to ID the ants, we just walked them over to a microscope, spent a maximum of five minutes there, and went back to count a new tube. Towards the end, though, we were getting really good at IDing the ants without a microscope. We are like ant species experts or something!

I guess the most important thing to learn from this is that of the 736 tubes that contained ants, we have zero left to count and ID. After spending three to four hours a day counting ants, a total of 498 personnel hours, we finished! I am told that no crew, since the first one back in 2010, has completed the All Island Ant Survey Ant ID. Go CAST VIII! And a special woop-woop to Colin for counting the largest number of ants in one tube…ever. 993 Monomorium pharoanis. That was a lot of rows of ants! I would also like to thank our Team Leader, Katrina, for listening to my ideas. Team work…I like it!