Bat-i-licious

Even blogs can migrate

2013-10-21T16:44:00.000-07:00

Monarch butterflies, caribou, dragonflies, hummingbirds, bats, and moths -- all of them can migrate and many of them do each year. And, it turns out, even blogs can migrate.

Visit my new blog on my website

I created this blog to document my transformation from business executive to biologist, but I stopped updating it after I finished my master's degree and moved from San Francisco to Tennessee to work on my Ph.D. Four years later, I've learned so much and had many adventures, catching bats in Texas and some tropical places, flying a Helikite, writing a book chapter, and even as a science advisor to the BBC's upcoming Cloud Lab expedition. I recently put up a web site so that I could share more about my research, and my blog is migrating from this blogger site to the new web site. Please join me there! You can also now follow me on twitter as well.

Same bats, different state

2010-07-20T16:53:00.000-07:00

These little beauties are Brazilian Freetailed bats, more scientifically known as Tadarida brasiliensis. I took their picture recently in the early morning as they streamed back into their home at Frio Cave in southern Texas. They were returning from a night of fine dining on corn earworms and whatever else was flying around way up there. There are probably a couple million bats in that cave, but we only caught about a dozen of them, roughly half males and half females, and the females were all on their way to nurse their pups.

You might remember that this same bat represented most of the calls I recorded during my research in San Francisco. I'm now working on my PhD at the University of Tennessee in Knoxville. I'm interested in migration, and will be focused on insect and bat migration during the fall over southern Texas. My advisor, Gary McCracken, and others have been working on these bats and the agricultural pests they consume for some time now, but most of that research has been focused during the spring migration and summer breeding season. We think that the insects migrate south on the cold fronts that blow down off the plains as the summer ends, and the bats find those concentrations of insects and use them to fatten up for their own migration south to Mexico. I'll be monitoring the bats and insects during September and October for the next few years in a variety of ways, looking for clues to explain exactly what is going on up there. I hope to also include high-altitude acoustic recording with balloons, unmanned aircraft, and NEXRAD radar imaging in future field seasons.

2009 bat meeting update

2009-11-12T17:38:00.001-08:00

I'm back from my fifth annual bat meeting in Portland and here's my semi-regular update with the highlights. This picture is the lovely logo created for this year's meeting by Willy Gibonney.

First the bad news. Bats continue to be killed at wind turbines and wiped out by White Nose. I attended one session describing roosts in New Hampshire that were unaffected until last year, and then were almost completely wiped out in one year. This was the first time I actually cried during a scientific presentation. The situation is so grim that people are actually considering culling bats, that is proactively wiping out bats in caves in an attempt to contain the epidemic. Tom Hallam, a professor here at UT, gave a paper with mathematical models showing that culling would have no effect on the spread of the disease. So far White Nose has only been seen in the northeast, though it's probably already here in Tennessee, but we don't understand it well enough to predict how far south or west it will travel. From my understanding, it appears likely that the fungus is spread both by humans and by bats. So if you're a caver, please try not to go into caves until we have a better understanding of this terrible situation. The US government has just allocated 1.9M$ for research, which will help. According to the Fish & Wildlife service the latest information will be available here.

There was somewhat better news on the wind energy front. Ongoing research has shown that since bats are more active at lower wind speeds, when turbines aren't generating much income, the technique of "feathering" turbine blades does reduce bat mortality. Feathering means turning blades into the wind so they turn slowly. The sweet spot is evidently around 5 m/s of wind speed. Preliminary models show that turbines that are not "cut in" to the grid until winds are at 6.5 m/s during bat migration times would represent only about 1% of total annual revenue loss. You can read the report from Ed Arnett and others yourself. And kudos to Iberdrola Renewables for being so cooperative and supportive of this important research, unlike other wind energy companies.

Aaron Corcoran won the student paper competition with his ultra-cool report on tiger moths jamming bat sonar (videos here.) I also presented my master's thesis results in the student competition. Student presentations are all given on the first day of the conference, with no concurrent sessions, so the whole audience may be watching -- maybe 350 people or so. I was very nervous and since my talk wasn't until 4pm I couldn't really focus on the other student papers, although I remember Aaron's and a few others. Of course I did just fine and once I was finished I was able to enjoy the rest of the conference. It is a really great group of people, and after 5 years of this many of them are my friends. Attending NASBR is one of my favorite parts of the year. We were in Portland, so I also got to visit Powell's books for the first time, and go beer tasting at the Deschutes brewery. Next year will be in Denver. I hope you'll be able to join us!

Be glad you're not a cave bat

2009-10-10T19:19:00.000-07:00

If you care about bats, by now you have doubtless heard about the horrific White Nose Syndrome (WNS). This is a disease killing up to 90-100% of bats overwintering in caves throughout the northeastern US, and we believe it is probably here in Tennessee by now. The disease is apparently caused by a fungus, Geomyces destructans, that may have been somehow brought to the US from Europe. This fungus thrives in cold caves and gets into bats who hibernate there. The fungus or something related to it kills bats by causing them to burn energy they need to make it through the winter. It was originally found in 2006 in a cave in New York state and has been spreading disease-like from that epicenter with alarming speed. Bat biologists can't say exactly what, if anything, can be done to slow the speed of this nightmare but are scrambling to evaluate alternatives. The government has closed all caves in the area, but has no control over caves on private land. It's a huge sacrifice to ask cavers to stay out of caves, but if there's a chance that humans are involved in spreading the fungus, it seems worthwhile to steer clear at least until we understand more.

Someone asked me recently if I was going to change my plans and work on WNS instead of bat migration. My response is, for now at least, no. It's just too depressing. I'm excited about some work my advisor has started looking at high-altitude foraging of Mexican Freetail bats as they track insect migrations and prepare for their own southward migrations in the fall. But it's too early to say what my research proposal will end up including.

For now, I've got enough on my plate just adjusting to life in Knoxville, keeping up with the core curriculum for newly entering graduate students, and learning the ropes of being a teacher myself. I managed to escape any teaching duties in San Francisco, but here I'm a TA for two sections of Bio 130, the introductory biology class for biology majors, covering biodiversity and topics such as ecology and evolution. The old saying that the best way to learn something is to teach it turns out to be true. It's kind of fun to have that captive audience of young, impressionable minds, and to see what kind of a difference I can make for them. The first step was to ban all cell phone usage of course.

The academic life here is every bit as intellectually challenging and satisfying as I had hoped. We spend time sitting around discussing topics such as "what is a species, anyway" and reading Darwin. Friday afternoons there's a seminar presentation by one of the faculty or some invited scholar, and most of the department turns out and then heads down afterward to the local pub to carry on the conversation. There are politics and gossip, of course, but it doesn't seem to be out of control. My education from San Francisco State gave me a solid foundation from which to follow most of the debates, for which I am very grateful.

Certainly, I miss my friends, and San Francisco, and familiar culture and climate. Adjusting to the move has been a larger challenge than I expected, in part due to some unexpected family tragedy just before I moved. But I am committed to this adventure and game to see where this leads me.

Bats of San Francisco: the answers

2009-08-20T07:07:00.000-07:00

After much hard work, I finally managed to complete my master's degree at San Francisco State University this summer. At this point, I know more about the bats that live in San Francisco than anyone else in the world.
If you've had the patience to follow along you will know that my study involved an acoustic survey of the bats that live here in the city, to understand what factors affect their foraging for insects. Here's what I learned. There are at least four species of bats in the city. By far (84%) most of them are Brazilian Freetailed bats (Tadarida brasiliensis ). Parks that have water in them also tended to have Yuma Myotis bats (Myotis yumanensis ). The two other bats I found were Western Red bat (Lasiurus blossevillii) and Little Brown bat (Myotis lucifugus). Bats are present and active all year in the city, with the highest activity levels in the fall. I found Freetailed bats in every place I looked, even in back yards. This is probably because they tend to fly high and forage over large distances, and their loud calls are easy to pick up on a recording. Yuma bats are known for hanging out near water, so it wasn't a surprise to find them near lakes and streams. However, they were not at all the lakes: I didn't find them at my recording location in Golden Gate park, at Stowe lake. Red bats migrate through in spring and fall but are known to over-winter in the arboretum in Golden Gate park. Little browns are the bat apparently most affected by white nose syndrome in the eastern US. They are really widespread and common, but I only found them in two locations: Pine Lake and the Fire Department's reservoir at the top of Twin Peaks.
The highest diversity of bat species were at those two locations. This is interesting because these are not large bodies of water, nor are they in large parks. Pine Lake, shown here, is in a medium-sized park with heavy recreational use. I considered five potential factors to explain this: park size, amount of tree edge in each park (where bugs like to hang out), distance to the nearest large park, distance to the nearest fresh water, and amount of native plants in each park. I used statistical modeling to understand what variables best explain the difference in number of species, as well as the difference in activity between the parks. The best explanation for the number of species was the distance to the nearest water.
One interesting thing I didn't find was Big Brown bats (Eptesicus fuscus ). These are very common and widespread, especially in urban areas. I am not sure why I didn't find any in San Francisco, as they've been found in nearby areas.
You can read more about the results of my research in the published article (pdf download). If you have questions about it please send me an email at jennifer at krauel dot com.

My 15 minutes of Internet fame

2009-04-17T20:45:00.001-07:00

I know, I know, you have been eagerly waiting for an update on my PhD plans. But first, I have to tell you that one of my bat photos appeared recently on my favorite web site, Cute Overload. This is one I took last summer while working down in the Caribbean. I guess the combination of a cute fuzzy animal butt ("tock" in CO lingo) plus the whole concept of a bag full of bats was enough to get selected. You can see more about bags of bats here and here.

And for my PhD destination, the winner is... Tennessee! I was very impressed with the faculty and other grad students when I visited there recently. I was lucky enough to get accepted there, one of the top schools in ecology and evolutionary biology. So I'll be moving to Knoxville this summer, and starting to study bat migration. But first, I have to finish that pesky master's thesis...

Eavesdropping on Golden Gate Bats

2009-03-22T14:05:00.001-07:00

Eavesdropping on Golden Gate Bats
Originally uploaded by unquenchable.fire

I'm almost done with collecting data for my thesis! I have only one more park to do, which will hopefully happen tonight if this storm passes today. I've recorded one night per quarter in each of 21 parks in the city. So far I've found four different species. Still to come: completing the analysis of this round's calls, doing the statistical analysis of my results, and then writing it up. I'm hoping to get everything together by the end of this month, so I can spend April writing, and schedule my thesis defense for mid-May.

I do have news on the PhD application front, but I'll post about that soon. The good news is I got accepted to at least one school for next fall.

In this picture, my detector rig sits in the tree in the foreground, aimed out over Stowe Lake in Golden Gate park. I haven't looked at the files I just got, but in the past I've had hundreds of Mexican Freetail calls, and a few Yuma Myotis calls from this location.

Catching the PhD train

2009-01-25T21:04:00.001-08:00

As I've mentioned before, I'm in the process of applying for PhD programs to begin next fall. I thought I'd write a bit about the experience which is alternately exhilarating, exasperating, and terrifying.

The process reminds me of looking for a job in industry, which is the only similar experience I've had. In that case, you research prospective companies, talk to people who work there, and if it looks good, submit your application. If possible try to do this at multiple companies at the same time, so that you can compare offers and select the best one. Repeat until you end up being such a good interviewer that someone eventually hires you.

Academia is like a parallel universe to industry, and understanding the processes is like trying to navigate a transit system in another language and country. The first parts are the same as in industry job-searching. Once I identified prospective advisors, I used my industry networking skills to have a chat with them to see informally if it was interesting on both sides, which isn't always possible in industry. After that, it gets very different.

The application process is rigid, arcane, and frequently frustrating. Each school has different deadlines, different formats for essays, different badly-designed online interfaces. Oh, and there's a test: the GRE, which bears no resemblance to actual skills needed in real life. Such as: when was the last time you needed to use long division? After you apply, you wait. I haven't figured out yet if it's good or bad to pester the hiring managers, er, advisors. For some schools, once they decide on a short list of candidates, they bring them all out at once for a visit, which may or may not be like an interview. I'm a bit hazy on the process after that.

I've applied for three schools, each with a leading researcher in the bat world where I could work on bat migration: Boston, Massachusetts, Knoxville, Tennessee, and Calgary, Alberta (Canada). All three are with highly-recommended advisors at excellent schools, each with different advantages. One's got a fabulous faculty line-up and great reputation in ecology, another's got great visibility and funding, and the third has a program that is the closest to what I actually want to study. I'm going to be a little coy about which is which, since these distinctions are really only relevant to me personally. Really, if I just get accepted to any one of them I'll be thrilled.

Right now I'm entering the nail-biting stage. All the applications are in, and I'm waiting. One school has already invited me out for a visit in another month or so, where I'll meet the faculty, other students, and we can do some mutual tire-kicking. The second school won't even begin to decide on a short list until then, and I haven't heard anything from the third.

Obviously this will have a huge impact on my life. I'm leaving San Francisco in a matter of months, possibly to a different country, and I don't know where I'll be. It's a big distraction from my current research. But on the other hand, it's super exciting and a big honor to even be seriously considered for these programs. Just a few years ago I didn't think it would be possible. Assuming I get into any one of these, I'll be fulfilling a dream.

The biologist's "holy relic"

2009-01-25T13:47:00.001-08:00

I'm just back from the first symposium on bat migration in Berlin, Germany. It was two intense days reviewing exactly how little we know about bats that migrate. Aside from lots of head-shaking at our ignorance, the main theme was pooling knowledge about migratory bat kills at wind turbines.

We've known for awhile that most of the bats killed at wind turbines are migrating tree bats. In the north western hemisphere that means Hoary bats, Red bats, and Silver-haired bats. It seems a very similar pattern is happening in Europe as well. I'll write more about this topic for sure, since this will be the focus for my PhD starting next year. For now, it was just a tease, and I must return to my current research on urban bat ecology.

The symposium banquet was hosted at the Museum of Natural History. We dined among the giant dinosaur bones but the highlight surely was this Archaeopteryx fossil -- the first evidence of feathers, the prototype bird. I've seen this image countless times, but to see the actual fossil was thrilling. It is arguably the closest thing that this group of biologists devoted to flying vertebrates have to a holy relic.

Notes from the 2008 bat meeting

2008-12-13T21:05:00.001-08:00

Here is my belated report from this year's annual North American Symposium of Bat Research (a.k.a. NASBR). This year we met in Scranton, PA, and this time without threat of hurricane, so pretty much all the regulars were there. I presented a poster again this year. This time it was about preliminary results from my thesis research on bats in San Francisco. You can see here a map I made showing the different parks in green where I'm looking for bats. So far I've found four different species, although most of the bats are Mexican Freetails (Tadarida brasiliensis.)

My primary goal this year, however, was to scout out potential PhD advisors. I had arranged a lunch meeting with two, and managed to get some time with a third at the conference. To my surprise, they were all interested in me and encouraged me to apply to their schools. I guess I thought that as a non-traditional student I would be less attractive, but it turns out the opposite is true; all that experience in the real world is actually worth something after all. Since my return from the conference I've been busy taking the GRE and asking for letters of recommendation and trying to navigate the grad school application process. How does anyone finish a master's degree while they're doing this? I"m applying to Boston University, University of Tennessee at Knoxville, and Calgary University. All very far from San Francisco, and much colder.

This year we had updates on bats and wind energy (they're still getting slaughtered at wind turbines) and on the mysterious and tragic white nose syndrome which is killing thousands of bats in caves in the northeastern US. The latter appears at this point to be caused by a fungus that may have originated in Europe, but the results are still very preliminary.

An uneasy alliance

2008-12-13T18:16:00.001-08:00

from Co-op America and the Green Festival

I have been a long-time member of Co-op America, which is soon re-inventing itself as Green America. It's a great organization, but in their zeal for doing good they tend not to hear inconvenient truths such as the impact of turbines on wildlife. I took the opportunity to stop by their booth at the local Green Festival to do a little consciousness raising of my own.

Bottomless Ghaut

2008-11-06T17:18:00.001-08:00

Toward the end of the trip we took a hike down into Bottomless Ghaut, one of the volcanic canyons on the windward side of Montserrat. Relatively inaccessible and protected, it is a refuge for rare species such as the Montserrat Oriole and the Sturnira bat. A "ghaut" is pronounced like "gut" in English, and apparently means a ravine of volcanic origin.

Our mission was to find and capture the rare bat Sturnira thomasi which is suspected of being an endemic species on the island. The plan was to attach radio transmitters to as many bats as possible and then return the next day to find out where they roost. To get to the netting location we had to hike carrying our nets and poles down a steep and muddy trail, which Scott cleared with a machete. We did manage to capture one Sturnira that night, but when we returned the next day with the radio receiver and antenna, we were unable to re-find her. So the mystery continues. We were lucky enough to glimpse the endemic Montserrat Oriole and see its nest, and hear many mountain chickens (actually frogs) although we didn't see one.

Only later did we realize the trail somewhere crossed a nest of chiggers, spawn of the devil. They provided me with an itchy souvenir of the trip that lasted long after my return to San Francisco.

After the volcano

2008-11-06T17:04:00.001-08:00

Of course we did take some time out to ogle the volcanic destruction on Montserrat. This photo is a view across what used to be a lovely golf course in the Belham Valley toward what surely used to be a lovely home. You can see the top of the volcano in the background. This volcano is different from others I have seen before in that it spews mud and ash (in a pyroclastic flow) instead of molten rock. While the river of super-hot mud is just as destructive and deadly as a river of molten lava, the result looks quite different from what you might see on Hawai'i for example. The dust gets into and onto everything.

We had one exciting moment when the volcano warning system loudspeakers announced that an eruption was imminent and we were to evacuate immediately. This was indeed possible, as an eruption had happened a week or so before we arrived. However, the timing was suspicious in that it happened exactly when the noon bell was due, and in fact later we heard that someone pushed the wrong button.

Processing bats at the Wide Awake

2008-11-06T16:43:00.001-08:00

Of course we also did research work on Montserrat although happily it didn't involve any killing of bats. We put up nets in areas that had been studied for many previous years in order to monitor activity and populations over time. On Montserrat it's especially interesting to look at the effect on bats of volcanic eruptions (pdf). For example, when the mango trees are covered with ash, the fruit-eating bats often have very bad teeth. In fact many of the bats we caught did have discolored, ground down or even missing teeth.

Many of the places we netted were in populated areas. They may not have started out that way, but since the big eruptions what's left of the population has migrated to the northern side of the island which is now starting to get crowded. One night we netted not far from our favorite bar, Gary Moore's Wide Awake, and took the bags of bats down to the bar for processing. We just parked in front of the bar and worked out of the back of the car. Some of the bar patrons were quite interested in the work.

We were on Montserrat during the Beijing Olympics and spent several post-batting evenings consuming Carib beers and watching the big-screen TV in Gary's bar.

Feeling hot hot hot

2008-11-06T15:57:00.001-08:00

For the second part of my Caribbean bat research trip we went to the island of Montserrat. This island is not a tourist destination at all and is most famous for its active volcano which destroyed the capital of Plymouth when it woke up again in the 1990's.

Of course we were there for the bats but I got an unexpected thrill when I learned that Alphonsus Cassell, a.k.a. Arrow, the King of Soca music was from Montserrat. Of course I had to visit his store, fabulously named Arrow's Manshop, to buy a CD with his famous song Hot Hot Hot. He was gracious enough to autograph it, and the team danced to Hot Hot Hot the rest of the trip.

Ardops Nichollsi

2008-10-18T23:48:00.000-07:00

The bats in the Caribbean are mostly very different from the ones we have here in North America. Many of them are leaf-nosed bats, Phyllostomids if you speak Latin, like the bats I saw in the Yucatan. This little teddy bear of a bat was classified as a "reproductive male" for reasons which are pretty obvious although some of them were even more alarmingly obvious.

On St. Lucia, not all the bats got released. The team had permits to "take" a certain number of each species. We knew each night how many of each species were to be kept, and the kept bats stayed in their bags until the next morning, when they were humanely euthanized and then "processed" more completely. This meant that tissue samples were taken for genetic analysis, and then they were preserved in formalin and taken back to become museum samples.

The good part of this is that future researchers can examine the bats for reasons we don't even know yet, and in the dreadful event that they go locally extinct, for example due to climate change, there will be a record of what they were. Only bats that are fairly common are taken, so it probably has little affect on the survival of the population.

The bad part is that we're all doing this work because we love bats, and so it's super hard to see them killed. This work is not for me, but I will not speak badly of those who do it.

Caribbean bat science!

2008-10-18T21:54:00.000-07:00

At long last, here is the first of my promised entries on my time catching bats in the Caribbean this past summer.

The first part of the trip was on the island of St. Lucia. When I arrived, the rest of the group was already in full swing. We went almost immediately into the field to catch bats. The routine worked like this. Around 5pm we'd pack everyone and all the equipment up into the two already-trashed rental cars and head for the field. The group usually split up into a couple of teams. Before it got dark we set up the mist nets. These are very fine nets made of black string that in theory is invisible. The joke, of course, is that bats can see in the dark, much much better than us. In fact this same group just published a paper showing that only about 5% of the bats that come near the nets are actually caught in them. But that's another story.

We checked the nets regularly, every few minutes. When a bat landed in a net, we took it out as gently as possible, sometimes getting nasty bites in the meantime. Of course, we've all had our rabies shots! Then the bat went into a bag hanging from our belts, one for each species. We used bat bags in the BCI class, but this time the bags are bigger to hold more bats, and it was so warm out we don't need to put them inside our jackets. After a few hours of this, or when it started raining, we took the nets down and got ready to "process" the bats.

This picture shows the team processing bats the night I arrived. You can see one of the released bats flying in the upper middle of the photo. Before the bats were released, they' were pulled one at a time from the bag and inspected. We checked for species, sex and reproductive status, and age. Then, the lucky bats were released to fly away free.

The other volant vertebrate

2008-10-07T14:54:00.000-07:00

And now a break from the usual bat entries to talk about the other volant (flying) vertebrates, birds. This past Sunday I spent a glorious day looking for birds in Pt. Reyes National Seashore as part of a fundraiser for the San Francisco Bay Bird Observatory.

This fundraiser takes the form of a bird-a-thon, where teams compete to see who can find the highest number of bird species in a single day. My team, the Feral Birders, generally chooses Pt. Reyes as a destination because as a long peninsula sticking out into the Pacific ocean it tends to attract a large number of rare migrating birds. There aren't many trees out at the end of the point, so the birds taking a break from their travels tend to collect in the few groves of pine trees available. These two pine trees past the ranger residence at the fishdocks held an amazing number of fall migrants, including Black Throated Blue Warbler, Palm Warbler, Prothonotary Warbler, Blackpoll Warbler, Townsend's Warbler, and Yellow Warbler. There was also an amazing variety of birders there to witness it. We shared the wonder with Joe Morlan's class, among many other lucky people. That was extra special because the group of friends I spent the day with were all alumni from Joe's class years ago.
Over the course of the day we saw 102 different species of birds, mainly due to the great skills of my teammates, since I've been neglecting my birding skills in favor of bat skills. Let me know if you want a full list of the species we saw. Other exciting animal treats included several Mola Mola (sunfish) getting parasites picked off by gulls while floating in the ocean near the lighthouse, piles of elephant seals on the beaches as well as groups flinging their whole bodies out of the water chasing fish, and a coyote walking down the road stopping up traffic a la Yosemite or Yellowstone.
All in all it was a very magical day for an excellent cause. You can help support my fundraising efforts by making a contribution online. Just select my name, Jennifer Krauel, from the "Program" list. Thank you so much for your support!

Buh-bye Lava Beds, hello caribbean

2008-07-30T17:37:00.001-07:00

Silver-haired bat Originally uploaded by unquenchable.fire

Sadly the fun is over at the BCI acoustic monitoring class and I'm back in San Francisco. After about 12 hours of sleep I feel almost normal. Our last night batting at Lava Beds was such a delight. We were in an area where the Ponderosa pine forest was beginning, so there were lots of trees but still some sage scrub between the groups of trees. The weather was cool but not cold and the skies full of stars. After exploring the area, we all stood in a clearing between the trees as the bats were released one by one with their tiny glow sticks. Many were very cooperative, hanging around to give us lots of great recordings. Some even returned, so there were sometimes two or three little magical fairy lights dancing among the treetops. Altogether for the class we had about 12 different species of bats and one of the star attractions was this darling little Silver-haired bat (Lasionycteris noctivagans) whose voice is way bigger than its size would lead you to believe. Tonight I leave for my next adventure, doing a survey of bats on two caribbean islands, St. Lucia and Montserrat. I'll post an update after my return.

At the ice cave

2008-07-28T12:09:00.001-07:00

At the ice cave Originally uploaded by unquenchable.fire

Another late night last night -- we didn't get back to the lodge until 2:30am. Last night we looked for bats in Modoc national forest, quite a different habitat from the past few nights. As a result we got different bats, more on that later. This morning I got a chance to sit down with one of the instructors and get help with analysis of my thesis data, e.g. figuring out what kinds of bats are in the city. It was great to finally get answers to my questions and tips for how to do what Joe called "forensic bat call analysis".

Tinkerbell

2008-07-27T15:34:00.001-07:00

I've been writing about the process of capturing bats so that we can record their calls for our reference libraries. There are a few different ways to release the bats. The simplest is to simply let the bat fly out of your hand. With practice you can shine a spotlight on the bat as it flies away, and hope that it will circle around so that you can record it as it passes. It's important that you keep track of the bat, so that you can know for sure what kind of bat made the call you just recorded. If you're not so good with the spotlight, you can also attach a very small light stick to the bat's belly. We use the kind of glue that's safe for kids to eat, since the bat will groom it off fairly quickly. Here you can see a light stick getting glued to the belly of a Mexican Freetail bat. The trick here is to hold the bat very gently so it doesn't feel like it has to struggle. To release the bat, you simply hold it in your hand and raise your arm up. If the bat is warm enough (and it should be if you kept it in your jacket), it will fly away after a moment. All you can see is the tiny light flying away. Sometimes they stick around, circling around the bushes and weaving in and out of the tree tops. It's magical to watch them like fireflies or Tinkerbell.

Where the bat bags are

2008-07-27T12:44:00.001-07:00

In my last post I mentioned that after the bats are captured in mist nets, we figure out what species they are, and then they go into small cloth bags. Most of them seem to settle down and rest in the bags. When there are lots of bats coming into the nets, then a single bag can contain up to a half-dozen bats. Then the bat bags go inside someone's jacket to keep them toasty warm. Here you can see Dylan in his job as bat bag repository. This is a very cool job, but sometimes has its drawbacks. For example, some species have a strong musky odor. Or sometimes the bats pee or poop in their bags. Then you get a pungent souvenir of the evening that hopefully won't last longer than the next laundry day. Alternatively, sometimes the bats in the bag are very active, or even agitated. Last night for awhile I held a bag of Big Brown bats against my chest in my sweater. Big browns are famous for being feisty. They tried to bite me through the bag and every once in awhile would chatter and squirm. When I held my hand over them with gentle pressure they calmed down and were just a nice heart warmer.

Bags o' bats

2008-07-26T18:01:00.001-07:00

More live action reporting from the BCI acoustic class! Today is the first full day of class. Last night we were out recording bats until 2am, so please excuse me if I'm not terribly coherent. Right now I'm taking a break from processing bat calls and waiting for dinner so I get a chance to post another update. Here's basically how this week-long class works. Breakfast is at 8:30am, which sounds great until you do the math on not getting to bed until 2:30am. Lectures start at 9am, when we gather in the great room here at the Winema Lodge next to Tule Lake and learn about different aspects of acoustic monitoring of bats. Today we went over the various species found in the Pacific Northwest and the call characteristics used to tell the different between species. For some of them it seems pretty impossible to tell them apart even when the experts are describing it. After lunch it's more of the same until dinner. Evenings are spent out in the field with the bats. There are three types of attendees. In addition to us students, there are a half-dozen instructors including the creators of the tools we are using in the field. There are also a team of "wranglers", experienced bat workers in the region who are here to catch the bats that we will practice our recording skills on. The wranglers head out just after dinner to set up nets at various locations and catch bats. They identify the bats and put them in small cloth bags which they store inside their jackets to keep warm. Periodically they transport them to a wide open space where the students and instructors are waiting. Then we release them in various ways and capture their calls with our recording equipment. We use those recordings to build up libraries of calls of known bat species. Those reference libraries are necessary to identify calls of unknown bats. Last night there were nets in different locations, and at least one of them was wildly successful. I think we had almost 100 bats to release! Sometimes there were so many that they put a half-dozen or so of a single type into one bag. At first we went slowly, spending time looking at and photographing the bats before releasing them. At the end there were so many bats we just let them go all at once. On the detectors it was like the finale in a fireworks show. The bat pictured here is an adorable Townsend's big-eared bat (Corynorhinus townsendii). Could those ears possibly be any bigger?

Live from Lava Beds

2008-07-25T10:50:00.001-07:00

Setting up equipment Originally uploaded by unquenchable.fire

This week I'm up at Lava Beds National Monument, near the California/Oregon border, for the BCI Acoustic Monitoring class. I'm so excited to see my bat friends, the lovely scenery, and get all my questions answered. Since we have internet access here, I'm hoping to post photos and some of the highlights as the week goes by, at least until I'm too sleep deprived to function. In this shot you can see some of my classmates and instructors getting the equipment ready to record calls at an evening fly-out from a nearby lava tube cave. We later recorded calls from about a dozen different species. I got my detector and recorder set up to do handheld recording. To do this, I listen to the bat calls using headphones, and when I hear a bat go by (sounds like a series of clicks) then I push a button to save the data for later analysis on my computer.

Bug trap

2008-05-14T13:56:00.001-07:00

After my first night of data collection I learned a few things: 1. It takes 30 minutes to set up the equipment but only 10 to take it down. 2. One of my recorders is not working, which I found out only after the fact. 3. Looks like there might only be Mexican Freetails in the city. Of course it's way too soon to tell. 4. There are very few flying insects in the city. 5. Some people are interested in what I'm doing, but most people in the city are careful not to look too closely. Kind of sad, but it bodes well for the safety of my equipment. I added a photo to my last entry so you can see the finished detector rig. And on this entry you can see my sticky trap for flying insects. It's a water bottle painted camo, with a coat hanger stuck inside. Double-sided tape holds an 8.5 x 11 inch transparency sheet to the outside. I spray it with tanglefoot and then hang it near the bat detector to get a sense of relative insect activity in the night. In the morning I wrap a second transparency sheet around the sticky first one and pull them both off. I've got to run now but will write more after I upload the second night's data and have a look at it.