Monday, February 28, 2011

Updated ALE Lab Website

Over the weekend I updated our lab website If you want to learn more about our current research and outreach check it out!

Friday, February 25, 2011

Ol' Punkin'

After a long, and not quite finished winter, this pumpkin has still retained some of its color and shape. I am not sure what broke it up to begin with, but the thaw last week probably softened it up for an animal to eat some seeds. I saw lots of deer tracks frozen in the mud.
If we let nature take its course this will self-seed into new plants.

Enjoy the weekend!

Tuesday, February 22, 2011

Further ecological impacts of the seven-spotted lady beetle

I recently stumbled upon an article that caught my eye...

"The co-occurrence of an introduced biological control agent (Coleoptera: Coccinella septempunctata) and an endangered butterfly (Lepidoptera: Lycaeides melissa samuelis)"

In a post long ago, I talked about an internship I had during the summer of 2007 with the Detroit Zoo. I worked with their restoration program for the endangered karner blue butterfly (KBB) (Lycaeides melissa samuelis).

Karner blue butterfly

Now I am studying the effects of exotic lady beetles such as the seven spotted (Coccinella septempunctata) on native lady beetles. Though, I had not taken much time to think about other native insects that could be affected by the exotic beetles. In this paper the authors reported observing both species co-occurring spatially and temporally with the eggs and larvae of the KBB. They also observed an adult beetle feeding on a KBB larvae. This observation is not shocking to me since lady beetles are generalist predators, meaning they can feed on a wide variety of prey.
Seven-spotted lady beetle

The conservation of endangered species is incredibly important since the loss of a single species has the potential to drastically impact the ecosystem. The KBB is also treated as an "umbrella species" because efforts made to preserve KBB populations, have benifited other native plants and animals that reside in the Oak Savannah habitat as well.

Oak savannah habitat in Southern Michigan

Schellhorn, N. A., C. P. Lane, and D. M. Olson. 2005. The co-occurrence of an introduced biological control agent (Coleoptera: Coccinella septempunctata) and an endangered butterfly (Lepidoptera: Lycaeides melissa samuelis). Journal of Insect Conservation 9:41-47.

Friday, February 18, 2011

Pollination experiment set-up

Here's a sneak peak at the set-up for one of my experiments this summer. We will be targeting when the brunt of pollination happens in the pumpkins by closing research flowers every 2 hours between 5 and 11AM in our research plots. If we see that pollen grains (and the resulting seed set) do not increase that much between 9AM and 11AM collections compared to our 7AM collections, then that means most of the pollen is deposited before 7AM. Counting the seeds in mature pumpkins exposed to these same restrictions will tell us if the pollination window corresponds to successful pumpkins. The cameras will be set up to record the number of bees, species and time spent visiting the flowers on the field edge, and in the interior of the field. This will give us a good idea who pollinates and how long it takes them.

Wednesday, February 9, 2011

Accuracy of lady beetle ID by volunteers

Over the past two years I have been surveying lady beetle abundance across the state of Ohio with the help of 250+ volunteer citizen scientists. These volunteers placed yellow sticky card traps in their home gardens for two 7-day sampling periods in June and August of 2009 and 2010. After each 7-day collection each volunteer examined their card for 14 different lady beetle species and filled out a data sheet indicating which species were present. They then sent us their data sheet and yellow sticky card so that all identifications could be verified and additional insects could be counted. To see images of these species check out our lady beetle ID guide.

In a future post I will review the diversity and relative abundance of lady beetles found but today I want to talk about how well the volunteers were able to distinguish between these tiny insects. Overall, volunteer identification accuracy of lady beetles in 2009 was 46.2% in June and 50.3% in August. Similar accuracy rates were found in 2010, with 51.1% of lady beetles correctly identified in June and 43.1% of in August. While this may seem discouraging to some of our volunteers, I think its a really positive finding that we can build on in the future. Each volunteer who participated in our survey attended a 2-hour training session. At these sessions we used a power point presentation to illustrate how to identify each species. We also had boxes of pinned insects. I think that this year I am going to bring examples of actual sticky cards collected in 2010 so that volunteers can see what the lady beetles look like on the cards, when they can be much more difficult to ID. We may also try and get some photos of lady beetles on sticky cards on the website for reference.

I also plan to target additional time towards discussing species which were most commonly confused. The multi-colored Asian lady beetle (Harmonia axyridis) was the most abundant of all species found in Ohio gardens. Volunteers incorrectly identified H. axyridis as ten other lady beetle species. Forty specimens (18.6% of specimens collected) were incorrectly identified as a native coccinellid, with the rare convergent lady beetle (H. convergens) accounting for 20 of these errors across the four sampling periods. Twenty H. axyridis specimens (9.3% of specimens collected) were incorrectly identified as another exotic species. Of these 17 were identified as the seven spotted lady beetle (C. septempunctata). Some also missed H. axyridis specimens on their yellow sticky card trap (13 specimens, 6.0% of total collected) or listed it as “other lady beetle” (20 specimens, 0.3% of total collected) indicating that they thought H. axyridis was a lady beetle species other than the 14 surveyed by the BLBB program.

I am not surprised that volunteers had difficulty identifying this species. It is called the multicolored Asian lady beetle because it varies in color from pale yellow to bright red. Some individuals have spots and others lack spots. The key identifying feature of this insect is a black "W" on the pronotum, a plate covering the insect's thorax. Michelle and Andy who follow our blog sent us some great pictures of the multicolored Asian lady beetle, check out our March 2010 blog post to learn more about this species.

Friday, February 4, 2011

Modeling bee data

I completed watching all of my video data of bees visiting pumpkin flowers from last summer! I am now in the works analyzing and modeling the data. Though this summer's data was preliminary, the modeling practice will come in handy with larger data sets consisting of multiple treatment scales like farm diversity, floral strip type and farm location.

Here's the run-down on the lingo above...In science you always want to isolate a variable that you want to test. We use the word "treatment" to describe that. For every treatment, you must have a "control", which is set-up in the same manner of the treatment, but is spared the actual treatment. For example, I wanted to test how pumpkin plants are affected by planting floral strips by them. Are the pests reduced? Are the pumpkins bigger? Do the bees transfer more pollen? To do this I set up 6 farms that will have floral strips (treatments), and 6 farms that will not (my controls). Each farm will use similar planting practices to make all of my plots as close to identical as possible. This allows me to see the effect of the floral strip, unobscured by the many other factors that may affect pumpkin.

On top of that basic experiment I have more treatments! Holy moly! My 6 floral strip farms are also nested within a gradient of environments, and matched with my 6 control farms. I have 4 farms (2 floral strip farms and 2 control) in areas surrounded by agriculture, 4 farms surrounded by a high ratio of forests and grasslands to farmland, and 4 farms located in areas somewhere in between those two extremes. With data coming from all of those locations I can attempt to answer questions like "how does the surrounding area affect the types of insects I find in the floral strips and in the control plots?".

The results of this may sound definitive, but this will only reveal a small part of the big picture. And even then, only if everything works. You can never completely control the interference which may affect your data, and that's why it takes a lot of repetition to flesh out the big picture. I am standing on the shoulders of giants before me who tested similar theories, and more research will proceed after me. Each one of us takes a wack at a great piece of marble, if you will, chipping away a little more mystery until a sculpture is formed.

Thursday, February 3, 2011

Grant writing and DNA barcoding

No, I'm not writing an NSF grant (yet!). The National Science Foundation is one of the premiere grant funding agencies in the US for basic science research. From what I know, the competition is brutal, so I'm probably in need of some skin-thickening before I apply for anything there. Some preliminary results might also be helpful!

What I've been working on are some more specialized grants. The American Arachnological Society provides a small amount of funding for research supplies, and I submitted my grant about 3 weeks ago. It's too early to feel any waiting pressure, but I am getting anxious!

I'm currently working on a grant funded through OSU which is their SEEDS program. I've written up my master's research proposal and will be requesting $3000. Somehow my research ideas are proving to be expensive! One of my goals is to molecularly analyze the gut contents of some of the spiders I will collect in three urban greenspaces in Cleveland: vacant lots, community gardens, and lots redesigned as natural areas.

Most gut-content analysis frames the question as "Who is eating this particular pest species?" Then, DNA tags which are specific to the pest species are used to find that tag within different potential predators' guts. This is helpful when researchers and farmers want to know which predator populations to invest support for conservation within particular crops.

But my question is "What are these spiders eating?" This is a hard question to answer for spiders because they are difficult to watch for long periods of time (not because they're boring, you just don't know when they're going to eat!). But there are ways to analyze gut contents without previous knowledge or species-specific DNA tags. What I plan to do is identify a "universal" sequence region of DNA within each spider gut. This region is within the COI gene which is found within mitochondria (the power supplies within cells). In fact, all animals (and other eukaryotes) contain mitochondria, so they all have a COI sequence. This sequence mutates relatively quickly, so in theory is quite different between species but consistent within a species. Ultimately, this region (other regions are used for plants) is used for"DNA barcoding," where you can identify a DNA sequence by comparing it to a database with already identified sequences. Using these methods, I can recover COI sequences from each spider gut and then run them through a database and viola, the database tells me what animal each sequence comes from.

It's sort of like if you have a word to translate from a language you don't know, so you put it through an online translator. My high school German is a little rusty, so when I type in "schreibe" I find it means "to write." And that's its only meaning. That would be a species-specific identification.

However, the result is only as good as the translator's dictionary, but you may come close. So if I look up the Finnish word "kirjoittaa" the translation results are: "write, type, compose, spell, print, author, put, etc etc etc". I'm in the neighborhood of what the word means, but it's not precise. For my COI identification, that's similar to the database telling me this particular sequences comes from the fly genus Brachyopa but that's it. My dictionary doesn't have anything more specific, but I'm close. Hopefully I can come at least this close in my research with all my sequences.

What makes this process expensive is how I plan to recover my sequences. First, the spiders will be ground up (sorry guys!) and all their DNA and the DNA in their guts will be amplified so I have a bunch of sequences to work with. Then, this recovered DNA needs to be sequenced (CAATTAAGGA etc. - I need to know which letters make up my "word"). A new fancy (read expensive) method of sequencing involves adding a specific tag to each "word" so I know which spider it came from ("schreibe-Spider1" vs "schreibe-Spider2" and "kirjoittaa-Spider2").

And then I'll know what these spiders are eating. This first summer I'm focusing on a wolf spider Pardosa milvina which from what Mary has found is pretty common in all the sites she's looked at so far. Later on I hope to identify sequences from a few different spiders and compare how their diets may overlap or complement one another.

What did you eat today?

Tuesday, February 1, 2011

A great read for the winter months!

I would highly suggest this book to anyone that is interested in how animals survive though the winter. I read this book about a year ago, and after last nights ice storm, I am considering reading it again. The adaptations animals have to survive harsh winters are amazing, and the author, Bernd Heinrich, includes some examples of insect survival as well! Heinrich has an amazing knack for noticing details in the winter world around him proving him to be a fabulous naturalist.

Stay safe in this weather!