Research Log
Here I will write weekly updates about my research project- including what I did that week, any problems I've run into, changes I might have to make, and more.
My Research
My project is an extension of a project that my peer, Owen, started last summer. He is looking at snakes and the effects of defaunation- the reduction of large and medium size mammals within an ecosystem. To. do this, the snake communities are being compared between two sites: Yasuní Research Station (YRS) and Tiputini Biodiversity Station (TBS). YRS has allowed hunting for years so will act as the defaunated site. TBS does not allow hunting and has minimal human impacts so will act as the site without defaunation. Owen hypothesizes that the defaunated site will have more small mammals such as rodents due to decreased predation and competition. He expects this to decrease overall snake diversity while the snake community will shift towards mammal eating species.
My project is looking at these effects on the frog and lizard population abundance and diversity. My methods are very similar to Owen's and include walking transects and using distance sampling to estimate the communities. We will be switching between YRS and TBS to ensure we obtain enough data at each site. I hypothesize that frog and lizard abundance will decrease at the hunted site. Hunting is expected to increase mammal-eating snake populations. These snakes are often not confined to a single food source and may eat frogs and lizards, especially as juveniles. As the snake populations increase, their prey- frogs and lizards- should decrease.
Week 1 (5/31- 6/6)
This first week was our first rotation at TBS. When we arrived we were given an orientation from our mentor, Gonzalo, to ensure we had a safe, enjoyable, and beneficial time at TBS. The first couple of days consisted of Owen showing me the ropes on how the research is going to be done. He explained the process before we went out, but I find the best way to learn how to do something is to actually do it. I was taught what data we will be collecting and the different instruments and methods for doing so. Data entry and collection are an essential part of research so even though it is a simple concept, it is highly important to be done correctly. Due to the nature of surveys, we are not able to spend a lot of time with each individual, so we need to input the data quickly. Within this data is the name of the species we are recording. There are a lot of species that are new to me, but I am slowly getting them down the more we see and collect data on, as well as through studying field guides and identifying species post-survey that we were not able to ID during the survey.
The first few days of this week consisted of travel and settling in to our new home. I am now starting to get into the flow of what this summer is going to be like. I am looking forward to the research part ramping up and learning more about what it's like to be a researcher in the field of ecology.
Week 2 (6/7- 6/13)
At the beginning of the week, we traveled to the other station (YRS). Owen and I were both excited, so after settling in we decided to do a night survey. We started the week out strong with a five snake survey- including a pit viper and a boa. We also spotted a lot more small mammals at this station, such as mouse opossums and rodents . Both of these help support owen's hypothesis that there are more small mammals at the hunted site which in turn increase the populations of mammal eating snakes. Unfortunately, the rest of the week was very slow and we found very few snakes. It's hard to know what exactly the reason for this is- it could be related to the weather, luck, or just poor detection skills.
It's still pretty early on, so it's hard to tell if there is a difference in frog and lizard communities. I want to have backup questions in case I find that there is no difference between the two sites. I read some papers to help me come up with questions that I may be able to explore. Some variables that I could look at which may be able to explain differences in frog communities include habitat type (terra firme- non-flooded forest or varzea- seasonally flooded forest), proximity to water bodies, and time since rain. I am going to start recording GPS points of every body of water I cross on survey to help me test proximity to water bodies. The different types of water bodies I can record are creeks, rivers, and ephemeral pools. I also need to start reading up on the diets and predators of the frog and lizard species to later help me determine if these are deciding factors in the community compositions.
Week 3 (6/14- 6/20)
This week continued the pattern from the end of last week. We only found a few snakes during surveys this week, most of which were the common blunt-headed snake- by far the most common snake we see here. A couple of the other groups are looking at anoles and also do night surveys. One group stays within a 40-meter diameter circle, slowly scanning every leaf, trunk, and crevice. This does not appear to be an effective method as they have only found a couple of individuals despite doing multiple surveys. The other anole group walks trails, similar to us, scanning for anoles. They seem to have more success finding anoles, but they have also only seen a single snake.
We have had some nights where very few frogs were found. During one of our survey nights, it started pouring down rain. Almost immediately, we saw a few Bassler's Humming Frog, a species in the same family (Microhylidae) as narrowmouth toads in the US. This supports the idea that time since rain does have an impact on frog activity, so I am excited to start analyzing my data and test if rain does have a significant impact. I will likely look at this by genus since frogs are so diverse in their behavior patterns.
In the afternoon of the 14th, the wifi stopped working, which was a little frustrating. Owen and I are inputting our data to Excel using the cloud. I was not able to access the sheet once the wifi stopped working. So this entire week, I was unable to input any of the data we collected or research the diet and predators of the frog and lizard species, leaving much to do next week.
Week 4 (6/21- 6/27)
We arrived at the new station this week, which means we have wifi again and I had a lot of data to input. I was also able to start researching the diet and predator information of the lizard species that we have seen and inputting it into our Excel sheet. I bought the book Reptiles of Ecuador, which has diet and predator information for most of the species we have seen, which makes this process pretty quick. I was not able to find any books on the frogs of Ecuador that were within my budget, so I will have to resort to the internet to find their information.
We brought on a student from USFQ, a university here in Ecuador, to help us with the field work. From our first survey, we could tell that he would be a big help- he often spots many frogs and lizards that Owen and I both overlook, increasing the sample size for my analysis. Now that there are three of us here, one person is able to stay back while the other two do a survey. Until now, Owen has been in charge of writing down the data in the notebook during surveys. He taught me how to do this so that JP and I could do day surveys on our own. While there are a few species that we occasionally find on day surveys that we don't often see on night surveys, the day surveys do not feel as beneficial since we largely find the same species as night surveys and find relatively few individuals.
I have been marking the water bodies we encounter on survey, but after some thinking, I've realized that this measurement may not be useful for testing proximity to water. There are many water bodies that are just off-trail that we do not see or creeks that run along the trails. Because of this, the map of points that I was creating would not be an accurate representation of the true distance to nearest water body. We have been tracking the number of water bodies we cross during survey so I may use this, but if not, I should have plenty of other variables to analyze.
Week 5 (6/28- 7/4)
We are continuing to find lots of frogs and lizards here. We don't find many salamanders, which seems to differ from YRS. The number of lizards here also appears to be significantly higher here, especially Anolis fuscoauratus, but the R analysis will tell me if this is really the case. We found a couple of snake species that were not blunt heads the first few days, including a coral snake (Owen's first coral snake on survey) and a garden tree boa (not a species Owen wants to see at this station as it goes against his hypothesis). The second half of the week was very rainy, making for some less-than-ideal survey conditions. The river rose a couple of meters in just a couple of days. This caused some of the trails to be chest deep in water, making it difficult to find most animals.
JP and I are continuing to do day surveys while Owen is able to stay back and work on what he needs to get done. After several surveys, we have gotten a lot more comfortable with the process which allowed us to complete the surveys much quicker than at first. The day surveys are still pretty discouraging since we find the same species as the night surveys, except in much smaller densities. I'm not sure if they will benefit my analysis at all but I feel like it is too late to remove the day surveys and we also have nothing to do in the afternoons so we might as well survey. I keep hoping we'll see a daytime snake, but that has yet to happen.
Week 6 (7/5- 7/11)
This week we were back at YRS for our final rotation. The rains from the previous week had really raised the water level. The water was several meters higher than where it was when we left, and it was still rising. Many of the trails were under water because of this, so we had to stick to a few terra-firme trails. This made us worried that we would not be able to sample all of the trails at least twice. Luckily, the water level dropped as fast as it had risen. By the end of the week, one of the flooded trails was mostly clear of water. Before the survey, we were not expecting to find too much since many of the animals likely had not yet made their way back from the terra firme habitat. We were correct to assume that, as we did not find any snakes and very few frogs.
Now that I have spent a considerable amount of time at both stations, I can say with greater confidence than before that there are fewer lizards and more salamanders at YRS compared to TBS. Most of our surveys, both day and night, we do not find any lizards, and even less so for anoles. Salamanders we see most surveys and sometimes we'll find two or three all in the same area. I'm not sure why this may be, but it will definitely be something I will be looking into and I am excited to see what I will find.
Week 7 (7/12- 7/18)
This is the last full week in the Amazon. As we are approaching the end of the field season, I am feeling bittersweet. This experience has been amazing, filled with many great memories and teaching me so much about the research process. Near the beginning of the week we finished our last day survey. This was probably one of our better day surveys since we found many different frog individuals, including many Rhinella and many poison frogs. We were hoping to get lucky and find a snake for our last survey but this was not the case.
The same patterns continued in this week's night surveys in terms of what animals we'd find on surveys- there appeared to be fewer lizards here than TBS, more salamanders, and more boas. We found multiple boas, both on and off survey, including a young rainbow on our last night, which was pretty exciting. Unfortunately no anacondas were found, which would have been exciting as well as beneficial to Owen's project.
As expected with research, we ran into a couple problems this week. We had another wifi scare where it was out for the afternoon, but fortunately, it was just for the afternoon and was working again that night. We realized that the humidity and temperature meter was not displaying the correct information. This is likely due to the amount of water it has been exposed to from the amount of rain and flooded trails we have experienced. The temperature appears to be relatively accurate, but the humidity seems to be higher than the actual humidity. Luckily this happened at the end of the season. We will have to cross refernece our readings with those of the TBS weather station readings, or throw out the humidity readings from after the device stopped working. On our last few days at the station, the power went out, and with it the water of our showers, sinks, toilets, and wifi. Luckily we only had a couple days of this, but I am not sure what the researchers that still have mulitple weeks left will do.
Week 8 (7/19- 7/25)
This week marked our travel back home. We spent a couple days in Quito before flying back home. Owen had to pick up some samples for a project he helped with last year to take back to the US. Now that I am home, I need to finish up with entering data, finshing up this website, and starting my analysis so that I can write up my research. While writing may not be something that I find super exciting, I am looking forward to improving these skills that will be useful in my wildlife ecology career.
