Summer Moth Data

I have been working on a moth project this summer (2021) to work out some project ideas I want to incorporate into undergraduate research at Austin Community College.

The goal of the summer project is to calculate a biodiversity index of moths at one location using incidence data (using photos) rather than abundance data. The majority of moth surveys use light traps and calculate biodiversity parameters using the captured moth abundance data. These projects also preserve and store specimens for further research and identification.

While abundance data may be preferred it has considerable drawbacks. For consideration of undergraduate research at a community college the biggest drawbacks are the preservation, preparation and storage of specimens for the long term. Most community colleges lack research lab facilities and extra storage space as well as the expertise to curate the specimens for long periods of time.

Fortunately, there are statistics that can calculate biodiversity parameters and indices using incidence data rather than abundance data. But there are also considerable drawbacks to using incidence data as well especially if coupled with a lack of facilities to store voucher specimens. For instance, observations may never be identified without a voucher specimen.

Given the potential drawbacks to incidence data, the moths of Austin, Texas are fairly well documented and the majority of them can be identified through a photo although there exist several exceptions. However, it is not necessary to identify everything to species to accurately describe the biodiversity of a group of organisms. The use of morphospecies can help estimate diversity even without specific identification.

By posting this in my journal I am hoping to share this protocol with a few people to get feedback to help refine the techniques I am using and to interest others in developing and/or participating in these projects.

Methods and Materials

The location, my home, for the moth sampling was chosen specifically for convenience. Having a convenient location for future students (their own homes) to conduct surveys helps to eliminate some of the potential barriers to doing research (e.g. traveling, discomfort in being in unfamiliar places, etc.) and it connects the student to the research at their own home making it relevant to their immediate environment. This is a key factor in helping students, especially those unfamiliar with scientific research, connect to research and to the scientific method.

The nights chosen for the survey were also out of convenience but with some attempts at meeting a few criteria. Nights of rain or high wind were not sampled. However, temperature, humidity and moon phases were not considered during sampling even though each of these were measured to determin later if they had an effect on the diversity of moths appearing at the light.

A blacklight was hung in front of a white surface 30 minutes before dark (usually around 7:30pm CST) and remained on until midnight. The light was turned off at the end of the survey period and not left on overnight so as to minimize any interference it might be causing in reproductive or feeding behaviors of the moths or any of the other arthropods that might have been attracted to the light.

Surveys were conducted using a camera. I took a picture of each moth species that appeared at the light. I would start taking photographs for about 20 minutes making sure that I had accounted for each of the species present and then I would repeat the survey every hour making sure to photograph any new moths at the light. Each survey date represented about 4.5 hours of blacklight luring and about 1.5 hours of total surveying.

I used 2 different macro lenses to take clear images of the moths and this greatly aided in the ability to take photos of the micromoths.

Photo processing was required to elimate bad pictures and to crop and rotate images for easier identification once put into iNaturalist. Each species from each survey was input into iNaturalist for purposes of records and identification.

The survey dates include:
4/23/2021
4/29/2021
5/1/2021
5/2/2021
5/3/2021
5/9/2021
5/30/2021
6/3/2021
6/5/2021
6/6/2021
6/7/2021
6/8/2021
6/13/2021
6/27/2021
6/28/2021
6/29/2021
7/1/2021
7/2/2021
7/13/2021
7/15/2021
7/22/2021
7/25/2021
7/26/2021
8/1/2021
8/3/2021
8/5/2021
8/13/2021
8/17/2021
8/23/2021
8/26/2021
9/5/2021
9/9/2021
9/10/2021
9/16/2021
9/17/2021
9/20/2021

Ongoing Results

I am currently still doing the surveys and plan to continue doing the surveys until the end of October.

The results that I have started to piece together are very rough still and unfinished because a great deal more work needs to be done to work in identifications (either to species or assign a morpho species designation).

However, the raw data downloaded from iNaturalist can be found at:
https://docs.google.com/spreadsheets/d/1asF68vCnoToNM31h4cyMY1xLCoGLUwmExuTL0PTnRrc/edit?usp=sharing
I have attempted to create a template for the biodiversity matrix and have done a preliminary incidence graph in this google sheets file. In the future I will be generating a species accumulation curve, a rarefaction curve as well as calculations for a diversity index. I will also look at relationships between diversity and physical factors like moon phase, temperature and humidity.

I have also created a project in iNaturalist to assist in keeping track of species and to facilitate identification. It can be found at: https://www.inaturalist.org/projects/moth-id-project

One of the other reasons that I took on this project is that I wanted to become more proficient at identifying moths. This project has given me a lot more exposure and practice at identifying families of moths by sight and familiarizing me with the set of species that visit this location. Since April I have identified around 300 species at my light which will grow as more of the "difficult" species are identified.

Other projects

I will be conducting these surveys with my organismal biology classes at ACC but in partnership with the cell and molecular biology and biotechnology classes I have funding to have them perform DNA barcoding on moths that may be difficult to identify. We conducted a test run of DNA barcoding on 6 different moth species that I collected from my light and had 100% success at DNA amplification, extraction and sequencing. The results also matched expected species.

The ability to DNA barcode difficult species will help to alleviate some of the problems associated with not having voucher specimens. I am hoping that eventually we will get funding to expand this research project and will be able to collect more specimens.

Conclusions

While I don't have any major data conclusions at this time I would like to say that the experience of doing this project has been very encouraging. the surveys were consistent and it helped my become much more familiar with some of the difficult species that I have had little experience with. So far this project represents about 50 hours of survey time and much more than that in photo processing and identification but it has been very engaging and has encouraged me to look deeper into the analysis of this kind of data.

Any feedback you have would be greatly appreciated and of course I want to thank everyone who has ever contributed an identification to the large number of moths I have posted this summer. If you have ideas, questions, or comments I would love to hear them. I am also open to new ideas and to collaborations.

Anotado por cmeckerman cmeckerman, 22 de septiembre de 2021 a las 04:30 AM

Comentarios

@gcwarbler I talked about showing you something I was working on this summer and so I pieced it together although a bit haphazardly. This journal post is a crude summary of what I have been doing and what I am planning on doing. More than anything it has been a great way for me to finally start feeling my legs on moth IDs. Although, like everything else, the more I learn the more I realize that I really don't know anything.

@sambiology @jcochran706 I thought I would tag you on this as well.

Anotado por cmeckerman hace cerca de un año (Advertencia)

This is great stuff, Curtis! Lots of work put in it, too. I can't comment on the statistical stuff much, as I'm not sure I understand it, but it seems like the Abundance data might be challenging. I say this because I'm a bit surprised that the Isophrictis moth topped the list, just going from memory (insert laugh here) on what I've seen in Williamson County. I have other moths that show up very commonly (Chuck is rolling his eyes because he know's I'm talking about Texas Gray). But I guess it's all location-based. Any concerns on Abundance bias given how moth numbers vary so much? For example, I might have 40 Texas Grays on one night and 2 the next. But if understand your Methods correctly, each date occurrence would only get one tick. Is that correct? Although I guess it will right itself over time, a rare moth could at least temporarily have a status not that different from a common moth. I think I'm just proving how little I understand about the statistical methods you're using!

One suggestion might be to collect rough habitat data associated with the survey site. For example, I have a pond out back of my house so I get many Petrophila. I have big oaks, so I got some nice Catocala species this Spring. Etc., etc.

The survey time, per day/night" was very interesting to me. I understand what you mean about wanting to avoid feeding/reproductive impact on moths by closing up shop at midnight, but I leave my light on all night sometimes and I'm amazed at the species differences between 8-12 PM and 430-700 AM. I almost never get any big sphinx moths during that 8-12 period. And recently I was getting all kinds of interesting Pelochrista during the 430-700 AM period. I should say "recording" instead of "getting", I suppose, since I'm sleeping during that 12-430 period, so I don't know exactly when those moths show up.

Finally, I love the comment on how your survey made you more proficient at moth ID. I've personally benefited from that result as you ID my moths, so many thanks. But wouldn't it also be great if one or more of your students got into this "hobby" too and could help ID moths? I bet 75% go unidentified/unconfirmed on iNaturalist.

Again, great work, and I'm looking forward to the next round.

Jack

Anotado por jcochran706 hace cerca de un año (Advertencia)

Great stuff! I'm having a busy Sept and Oct but as soon as I have a window of opportunity, I hope to really dig into your project.

Anotado por gcwarbler hace cerca de un año (Advertencia)

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