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Jesse D. Walker Utah State University, currently enrolled in a Ph.D program in Ecology/Biology (working with Jim MacMahon) BA, Integrative Biology, UC Berkeley Summer Scorpion Count (5/30): 174 Email: jdwalker *at* cc.usu.edu AIM: "calwolf" Yahoo: "calwolf24" MSN: "calwolf" My CV (pdf) Also available: my Resources for Undergraduates page A direct link to MY PICTURES My Financial Advice page |
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| Scorpion Community Ecology (my research) Well, the summer research season has begun, but I've only spent a little time in the field so far (needs to be warmer, and not raining). I'll likely spend a good portion of my summer over in Box Elder County, Utah, studying the scorpion populations at a site that someone else in the MacMahon lab (Scott Newbold) has already done some work at. There is a nice elevational and habitat gradient there that he has established (it's about 10km long total, running from the juniper-covered mountains to the salt flats near the lake). He studied ants and horned lizards there for his doctoral dissertation, but I think it's a much better site for studying scorpions. From what I can tell, the densitities there just *might* be as high as in some of the best-studied scorpion populations on earth. I haven't done a really good survey yet, but there seem to be a number of areas out there where the burrow density seems to be about one per square meter. That equals a lot of scorpions on the landscape level. There are at least three scorpion species at the site: Anuroctonus phaeodactylus, which is fairly large, and an obligate burrower. The females and young rarely emerge from their burrows, while the males can often be found on the surface. Theother species that's relatively abundant there is Vaejovis confusus. I've also collected a few specimens there of another species (Paruroctonus boreus). They were in an area that was somewhat marginal to the region I was surveying, because the habitat was a little different (rockier slopes). I also have a secret hope that I might find the giant hairy scorpion (Hadrurus spadix) in the area. I'm currently interested in the mechanisms that enable ecolgically similar species (that eat the same thing, etc) to live together. One ecological theory states that similar species shouldn't be able to co-exist, since one of them will always be a slightly better competitor than the others. Stated one way, "complete competitors cannot co-exist". So, the species involved must not be complete competitors... that is, there must be some significant differences in their life history traits that make them slightly different ecologically. Sometimes, body size will allow that (with larger animals eating larger prey, etc). I don't think that's the case with these scorpions, since they are pretty closely matched in size. Soil has been shown to be an important factor in separating other scorpion species ecogically, and I think it may be in this case also. I'll spend part of this summer trying to figure out that relationship, and hopefully come up with some better-developed research questions in the process. During part of this summer, I would also like to do a large-scale survey of Great Basin scorpions. I'll start by doing a lot of driving and camping. I intend to cover a large portion of western Utah, head into Nevada, and also cover portions of southern Idaho. My goal with this is to find as many scorpions as possible, search for a permanent field site (if I don't end up working at Scott's site), and study how each of the species that I encounter selects its habitat throughout the species range. It's also an excuse to get to know the great state of Utah, and do some camping in the process. |
| Snakes (another interest) I spent two summers (2001 and 2002) working on the Angelo Reserve helping out with research conducted by Mary Power and her graduate students. The area has a wonderful population of Western Aquatic Garter Snakes (Thamnophis atratus), so I got plenty of practice observing, catching, and taking data on these snakes. I went through a fairly regular process when I caught each snake: measuring (SVL), weighing (using a 100g Pesola scale), and sexing them (via hemipenal eversion for the juveniles, or by probing the adults). I'm glad that I've had some exposure to snakes in the field. I am particularly fascinated with rattlesnakes and other viperids. I caught several rattlesnakes (Crotalus viridis oreganus) during my Summer 2002 adventures on the Angelo Reserve, and gained some long-desired experience. I used a 40" snake hook and restraining tubes to handle the snakes. They were actually much easier to probe than the racers (Coluber constrictor) or garter snakes I caught during the summer. I spent the summer of 2003 working for Jeff Smith and Matt Goode, biologists at the University of Arizona. We worked outside of Tucson, AZ. We had a number of tiger rattlesnakes (Crotalus tigris) that we were radiotracking, in addition to a couple lyre snakes (Trimorphodon biscutatus). We also were checking on lizard populations (mostly Side-blotched lizards, Uta stansburiana, Tree lizards (Urosaurus orniatus), and spiny lizards (Sceloporus magister). Fun summer. Happy nights of crusing the course on a golf cart, bagging any rattlesnake I found. Gila monsters, too. And sleeping on the 16th tee... ahh... Anyway, I also have two snakes of my own. I got them because I realized that I wanted to know more about snakes. I have a female Honduran Milksnake (Lampropeltis triangulum hondurensis) and a male garter snake. I'm not quite sure what the garter is, because it was wild-caught and unusually patterned. It has more red coloration than a garter snake is supposed to have (hypererythrism?). Judging by where it was captured, it's likely either a Western Terrestrial (Thamnophis elegans), a California Red-Sided (T. sirtalis), or a hybrid of the two. The milksnake was purchased at the East Bay Vivarium, a great pet shop in Berkeley. Both of my snakes are great, and feel that I've learned a lot from them. |
| GIS Geographic Information Systems are a tool that can be very powerful for answering research questions with a spatial component. I've had two courses in GIS (see my webpage for Geog. 188), and I'm now fairly comfortable with the basic functions of ESRI's ArcGIS software. |
| Statistics I've had kind of a love-hate relationship with this subject. All scientists need to know statistics. It's the tool that makes data analysis possible in our fields. And it's not a bad subject. Not nearly as scary as I thought it would be before I had any exposure to it. I started with a semester of a class called "Intro to Statistics for the Life Sciences" taught by Steve Selvin at Cal. Good class. Enjoyed it. Got an A. The next semester, I started taking the next class in the series, taught by Maureen Lahiff in the Public Health Department. Also a good class. I had way too many other classes that semester, so I let that one go mid-semester. The same semester, there was a half-semester course taught in our department for graduate students called "experimental design and statistical analysis" taught by John-Marc Hero, a visiting lecturer (and a herpetologist!) from Australia. I audited this one since I didn't want the pressure of the final assignment (and I had lots of other classes). I made it to all the lectures and labs though. The course was taught with as little math as possible, focusing on the practical aspects of data analysis. My last class on statistics (EPS 120) was great too. Well, the content anyway. Their policy on the acceptance of late work was really harsh. Wonderful class though. Anyway, the foundation of my background in statistics has been layed, and I feel fairly comfortable with the subject. Like most researchers, however, I'll need to review the applicable specifics for every new project I start so I can work out the details of the experimental design. I'll be taking more statistics at Utah State as needed (multivariate, and maybe Biometry). |
| Cycling Well, I still call myself a cyclist, but I haven't been riding nearly enough lately. I have two bikes, a Bianchi road bike and a 2001 Specialized Rockhopper Pro mountain bike. The Bianchi is pretty much self-built, since I've replaced and upgraded most of the components on the bike. Anyway, my interest in cycling started when a church group I was a part of decided to take a nice long ride from Los Angeles, California to Salt Lake City, Utah in July 1997. It was a great experience. It was hot, and some of the days were long (128 miles from Las Vegas, NV to St. George, UT in 115° heat, much of it uphill). But it was a lot of fun. Since then, I don't think I've done any rides longer than about 50 miles, and I currently haven't been on my bike for real rides in way too long. I intend to start riding again when it warms up in the spring. I wonder if I'll have enough free time...? |
| Scuba Diving I'm a scuba diver. NAUI certified, currently at the Assistant Instructor level. I'm also an AAUS-certified scientific diver, which basically means that if I wanted to do research underwater using scuba, I can (currently to 60 feet). Most of my diving experience has been in association with UC Berkeley's Diving program, led by Jim Hayward. I started in the Fall 0f 2000 by taking the introductory scuba diving class (PE 47), which led to a basic and advanced certification. The following semester (Spring 2001) I took the scientific diving class (PE 407), and since then I've helped out with the class as a Training Assistant a number of times. Jim Hayward is a great instructor, and the class offers a lot of good training. I love diving, and want to do more of it (like a lot of other things). I recently moved to Utah, and am hoping to continue diving here. There is a dive shop here in Logan, and apparently the visibility at Bear Lake (about 30 miles away) isn't too bad. I have all my own gear, so I just need to get there and do it (after I find a dive buddy). Maybe soon...? |
| Backpacking I'm certainly not the most experienced backpacker in the world, since it's not really something I ever did growing up (hung out with the wrong crowd I guess), but I've been on a few trips now, and I'd really like to continue that trend and spend a little more time outdoors in the wild places. I love it! Here's my list of trips: Jan 2002: Big Basin State Park (with Julian and two of his friends) Jan 2003: Big Basin State Park (with church friends) May 2003: Big Sur (Los Padres National Forest, Ventana Wilderness) June 2003: Sheep Mountain Wilderness, Angeles National Forest (with my brother) August 2003: White Pine Lake, Wasatch-Cache Nat'l Forest (solo, one night only) There are pictures from some of my trips HERE |
| Photography I've had a digital camera for a while now. At first, I was using the SCIBUGS club camera, a Toshiba PDR-M25 (2.2 Megapixels). Great camera, took wonderful macro shots... I decided to get my own, and stayed with the Toshiba brand, but a higher model, so I now have the Toshiba PDR-3330 (3.2 MP). It's nice, and works great (lots of advanced features the other one didn't have), but it doesn't focus quite as close as the other camera, which was sort of disappointing. Anyway, I have taken thousands of pictures, and some of them have even been good! To see some of them, click HERE. Sorry I haven't set up a better viewing method yet (I'm working on it, there's a program I just found out about that may make that process much easier). Obviously, I don't want the pictures used commercially without my permission. All of the pics were taken by myself using one of the two cameras mentioned above. Update: now using a Toshiba PDR-M25 again... better macro photos. |
| Sustainable Development I don't have much background in this area, but that hasn't kept me from forming opinions. It seems to me that an ever-expanding human population won't be able to continue to grow on an Earth with finite space and resources. Sadly, my training as a biologist hasn't taught me as much as I'd like about how to sustainably exist on an Earth that has a finite area and quantity of natural resources (excluding the possibility of an apocalypic, end-of-the-world scenario). Especially if resources (timber, oil, etc) continue to be extracted at a rate faster than they can be replenished. During the semester of Fall 2002 I took a class that exposed me to a different was of looking at issues that I hadn't previously considered. In this worldview, people realize that there's currently an imbalance in the way we are living and that we're doing a lot of damage to the environment that is going to be difficult (if even possible) to fix. Without some kind of mitigation, as more plants and animals go extinct through over-exploitation, habitat destruction, or other anthropogenic effects, there will be an increasing breakdown in global ecosystem services like air and water purification, nutrient cycling, and soil formation. As Aldo Leopold (an early conservation biologist) said: "The first rule of an intelligent tinkerer is to keep all of the pieces". We seem to be entering an era where the Earth will be losing pieces more rapidly than ever before, possibly on the same (or greater) magnitude as any mass extinction. Much of this destruction is avoidable if we can find a way to consume fewer resources, curb the destruction of natural areas, and reduce the chemical wastes that are killing not only other species but our own as well. I believe that it isn't impossible to achieve a balance that will enable the perpetuation of both human and non-human species. We will need to rely more on renewable sources of energy (solar, wind) and not extract resources (plant, animal, or mineral) faster than they can be replaced by natural processes. We will also need to become increasingly aware of our dependence on functional ecosystems. How should we do that? I have no idea. What role do issues of social justice play in the preservation of biodiversity? I don't know. What about the exploitation of people and nature by corporations? I'm not sure. These are issues I'm sure I'll have to think involve the practical application of the priciples of ecology to actually make it all work. I'm currently trying to learn more (I've also taken classes on International Rural Development Policy and Ecosystemology). There are lots of good books written on the subject, and I have a few I'm looking forward to reading (see my reading list for some of the ones I've tackled). |
