So you may be wondering just what exactly my fieldwork
entails. Well, read on to find out!
First, a summary of what my project is about. I’m working
with the endangered Mexican long-nosed bat (Leptonycteris
nivalis) in northeast Mexico (the states of Nuevo Leon and Coahuila). Every
spring and fall, Mexican long-nosed bats migrate over 1000 km (600 miles)
between their mating cave in central Mexico and their maternity caves in
northeast Mexico and the U.S. Southwest. (A maternity cave is where the females
give birth to and raise their pups.) During this migration, the bats feed on
the nectar and pollen of agaves and cactus plants. However, in the northern
portion of their range where I’m working, they feed solely on the nectar and
pollen of agaves. People in the region also harvest and use agaves for a
variety of purposes, including several beverages and food products, forage for
livestock, and housing material. In order to help conserve the bats, I’m
working in several rural communities throughout the region to understand how
they are using agaves and if there may be opportunities in the future to
promote “bat-friendly” agave harvest and management. I’m also trying to figure
out what the bats need in terms of food (agave) resources when they are in the
region in the summer.
In order to do this, I’m doing three separate but
interrelated things during my fieldwork. First, I’m using infrared cameras to
monitor and count bat feeding visits to flowering agaves. Second, I’m
conducting agave surveys in the areas where I monitor for bats. With this
information, I am trying to understand what draws the bats to an area to
forage, or in other words, what makes a “high quality” foraging area. For
example, do the bats prefer areas with high numbers of flowering agaves all
clustered together, or do they prefer areas with the agaves more spread out? Do
they prefer agaves with more flowers?
The third part of my fieldwork is to conduct interviews with
community leaders and agave harvesters and also do participant observation
(where I observe harvesters in the field as they harvest the agaves). The goal
of these activities is to learn about how the community is currently using
agaves and how this has changed over time, and to understand what may
incentivize their adoption of “bat-friendly” practices in the future. One
example of “bat-friendly” practices is planting agaves and letting some flower
to feed the bats, instead of harvesting all the agaves in an area.
I am working in nine communities in five different areas
throughout Nuevo Leon and Coahuila. The farthest communities are about 375 km
(230 miles) apart. My “home base” is in the city of Monterrey, Nuevo Leon,
which is the second largest city in Mexico. I have a room in a house where I
stay when we’re not in the field, and typically we have two days between each
field trip (to recharge all the equipment, download videos, buy materials,
etc.). The farthest field site is about 250 km (155 miles) from Monterrey and
takes about 4 hours to reach. The other sites are only a couple hours away.
Some communities are located on or near the highway, while others are located
30 or more minutes down a dirt road from the highway. On top of that, we
sometimes have to drive farther into the boonies down not-so-great dirt roads
to reach an area with flowering agaves to set up the cameras. Also, there are
two general areas where I’m working: in the forests of the Sierra Madre
Oriental mountains, and in the desert scrub area of the Chihuahuan Desert. Each
offers very different scenery!
Agaves in the Sierra Madre Oriental mountains (left) and the
Chihuahuan Desert (right).
In general, each field trip lasts between two and five days,
during which time we do nightly monitoring of bats feeding at agaves, agave
surveys, and community interviews. Fitting all this in every day can be quite
the challenge! Below I’ll go through a “typical” itinerary so you can see just
how crazy the schedule can be…
To start a trip, the field team meets at my house in
Monterrey. The core team includes Ana (my translator), Temo from the NGO I’m
working with, and Jaileen (a Master’s student from Texas A&M also working
with the Mexican long-nosed bat for her project). Sometimes others may come too
if we need extra hands or if somebody else can’t go. When we meet, we load the
field truck (which I’m renting for the summer) with all the equipment,
including four cameras and clipboards, four infrared lamps and numerous 12V
batteries, eight tripods, a bag of agave survey tools, five camp chairs, tents,
sleeping bags and sleeping pads, a cooler, a camp stove and dishes, a bag of
extension cords and outlet splitters, a bag of chargers (for the camcorder
batteries and lamp batteries), my laptop and several external hard drives (to
download each nights’ videos since I only have enough SD cards for two nights
of monitoring), and our personal gear. It’s quite the menagerie of stuff!
Just a fraction of the batteries I must charge before every trip
(and every day while in the field before every night of monitoring)!
Packing up the field truck with all the equipment.
Once all packed, we head out on our several-day outing. When
we arrive at the community, we typically drop all our equipment and gear off at
our “base camp”, where we will sleep after each night of monitoring. Sometimes
our base camp is the community’s civic building or church, sometimes we rent a
small house or room from a family, and sometimes we rent a cabin in a
campground, depending on what’s available. With all the electronic equipment,
it’s important to have electricity and outlets if at all possible so I can
recharge all the batteries every day, since the batteries only last for one
night of monitoring.
All the equipment at on of our base camps (in a
destilado production facility in one of the communities).
Our sleeping area at base camp.
Another type of base camp: a family's house.
After setting up at base camp, we head out to scout for
flowering agaves to monitor at night. This usually involves driving around awhile
until we find a potential area with agaves, and then walking around checking
out all the flowering ones to find the best ones to monitor. So what exactly
makes a “good” or suitable agave to monitor? Well, first and foremost, it must
have open flowers with nectar for the bats. We often find a range of stages of
flowering among the agaves in a site. Some are too young (with flowers that
aren’t yet open) and some are too old (with old flowers that no longer have
good nectar, or with fruits already developing). It often happens that we find
an area that looks like it has good agaves from a distance, but then when we
walk to the site to check the flowering agaves are too old. Then we’re back to
square one trying to find another area. But when we do find “good” agaves with
the right stage of flowering, I pick the “best” one in each of the four patches
where I’ll monitor with the four cameras. The “best” agave means having the
most open flowers, and therefore the most food available for the bats.
Scouting out the area to find four "good" agaves with
open (but not too old) flowers to monitor at night.
(Photo by Ana Castaneda Aguilera)
The progression of an agave's flowering: First photo: Too young (flowers not open).Second photo:
A good agave, with at least some open flowers.
Agaves flower from the bottom of the plant upwards, so you can see here that
the bottom flowers are open, but the upper ones are still closed. Third photo: An agave that flowered this year, but is now
too old to have good nectar for the bats. The bottom flowers are already
developing fruits, and the top flowers only have old nectar. Fourth photo: An agave that flowered in a previous year. The
fruits are dry and open after they split open and shot out their seeds to the
ground.
Once we’ve found a good area and selected the agaves to
monitor for the next few nights, we begin the agave surveys. This entails quite
a few things: taking photos of the area, taking GPS coordinates and photos of
every flowering agave within each monitoring patch, counting the number of
umbels (groups of flowers) that have open flowers, closed flowers, etc. on each
flowering agave, measuring the height and cover (the length by width of the
base) of each flowering agave within each patch, and counting the number of
non-flowering agaves in each patch. These surveys typically take two to three
hours to finish. Sometimes if we run out of time before nightfall, we have to
return the next day to finish. I’m pretty sure the agave surveys are my least
favorite part of my field work. Standing out in the beating sun for hours on
end trying to count agave flowers is a hot, tedious task that makes me glad I’m
not a field botanist! I’d much rather be sitting out during a tranquil night
under the moon watching or chasing bats!
Taking photos of the area to monitor that night.
(Photo by Jaileen Rivera-Rodriguez)
Taking GPS coordinates. (Photo by Jaileen Rivera-Rodriguez)
Taking photos of a focal agave. (Photo by Jaileen Rivera-Rodriguez)
Counting the number of open flowers
on the focal agave. (Photo by Jaileen
Rivera-Rodriguez)
Ana measures the cover of the agave plant, while
I take photos of the plant. (Photo by Jaileen Rivera-Rodriguez)
Ana measuring the height of an agave.
Measuring out a 30 meter patch to count all the agaves.
Sometimes the terrain can be a bit steep, in which
case we get our exercise!
More measuring... (Photo by Jaileen Rivera-Rodriguez)
A hummingbird visits our patch while we do our agave survey.
(Photo by Jaileen Rivera-Rodriguez)
Once the sun starts to set, we set up the four infrared
cameras at the focal agaves. This can take up to an hour, depending on the
terrain and other factors. At each focal agave, we put a Sony camcorder on a
tripod about 10 meters from the agave, and the infrared lamps on a tripod about
five meters from the agave. The IR lamps illuminate the flowers so we can see
them in the dark, but the IR light isn’t visible to the human (or bat) eye.
Hauling the equipment to the focal agaves.
(Photo by Sergio Aviles)
Beginning to set up the cameras.
(Photo by Jaileen Rivera-Rodriguez)
Showing how to use the Sony camcorder.
(Photo by Bernardo Marino)
We're setting up the IR lamps. The camcorder is already
set up in the foreground. (Photo by Sergio Aviles)
Getting the camera ready. (Photo by Sergio Aviles)
Three camera and IR lamp setups, with the camcorder in the foreground, and the IR lamps closer to the agave to illuminate the flowers.
These are the IR lamps that allow us to
see and monitor at night without disturbing
the bats, like normal visible lighting would.
Once the cameras are set up, we usually have a little time
(20 minutes or so) before we’ll actually start monitoring (we typically start
at 9:30pm). During the waiting time, we complete one of the most important
tasks of the day: making dinner! Field dinner usually means peanut butter and
jelly sandwiches, peanut butter and Nutella sandwiches, or ham sandwiches. We
usually make two per person, one for dinner before monitoring, and one for a “midnight
snack” while we’re out sitting at the cameras until 3:30am.
Sometimes if we’re lucky we can find someone in the
community who can cook for us (of course we pay them and/or provide the food to
cook). Those are good days when we get delicious homemade gorditas or other
regional food instead of peanut butter and jelly sandwiches! On those days, we
usually pack up the food to take with us in the field. We also then get “breakfast”
the next day after we wake up, so around 1:00pm.
The important task of making (and eating!) field dinners! We often have an assembly line
for making the sandwiches. Quite efficient!
Finally, once the sun has set and it’s dark out, we’re ready
to start monitoring for bats. We monitor for six hours every night, between
about 9:30pm and 3:30am. “Monitoring” means sitting at each of the four cameras
and periodically watching the camera for bats and recording the number of
feeding visits on the data sheet. Each camcorder also records the whole night
so that I’ll be able to watch the videos fully at a later date to get more
accurate numbers of bat visits.
Depending on how many cameras we have out and how many
people we have, sometimes we monitor in pairs, and sometimes alone. If we have
enough people, we can take turns taking naps in the truck. However, I always
stay up the whole night to monitor, just in case something happens with the
cameras, etc. Multiple people have asked why we can’t just leave the cameras out
by themselves, and why we have to sit out with them the whole night. There are
several reasons. First, there is always the chance of rain, and if it does start
to rain we have to cover all the equipment with plastic bags (if light rain) or
pack everything up (if heavy rain). We can’t take the chance of the equipment
getting wet while we’re sleeping! Second, the camcorder and IR lamp batteries
have to be changed periodically throughout the night. Finally, things sometimes
go wrong, and there must be a person there to fix it. For example, the IR lamp
fuses sometimes blow, in which case we have to change the fuse. If we were all
sleeping we would lose hours worth of data (since without the IR lamps we can’t
see the agaves)! Another unfortunate thing that can happen is the camcorder
battery dies suddenly. If this happens, the video doesn’t save on the memory
card, and all the data is lost. To avoid data loss, we stop the recordings and
start new ones every hour or so. For all these reasons, we must physically be
out with the cameras. We all carry walkie-talkies so we can communicate with
each other, and I can tell when to watch the camera, when to change batteries,
etc. On nights when there is little or no bat activity, it can be hard to stay
awake the whole time. But that’s why I always set alarms on my watch!
This is what the agave looks like through
the camcorder lens, illuminated by the IR lamps.
Sitting with a camera to watch the agave all night.
(Photo by Isra Castrejon)
Watching bats under the amazing
desert stars! (Photo by Sergio Aviles)
Another great shot by Sergio Aviles.
I also have a pair of night vision binoculars that I
use to scan the area for bats. This is a photo taken
with these binoculars.
At around 3:30am, we start packing up everything to return
to base camp. This usually takes 30 minutes or so. The drive back to base camp
can take anywhere between 15 minutes to an hour, depending on how far away the
monitoring site was. Once back, everyone else goes to bed, and I stay up awhile
longer to put all the batteries on their chargers and start downloading the
camcorder videos onto an external hard drive. The batteries take up to seven
hours to fully charge, and each camcorder’s videos take about 1 ½ hours to download.
This means that for every night of monitoring (assuming we used all four
cameras), I must download six hours of video. And the memory required is
staggering! Each night, each camera records about 130 GB of video. Multiply
that by four cameras and many nights throughout the summer, and you get A LOT
of memory needed! I bought seven 4 TB external hard drives, which should get me
through the summer...
With all the charging, downloading, etc., I get to bed
typically around 5:00 or 5:30am. We normally sleep until around 10:30 or 11:00am.
It’s definitely not a lot of sleep, or very restful sleep!
Sleeping during the day after six hours
of monitoring. (Photo by Bernardo Marino)
When we get up in the late morning, I often have interviews
to do with community leaders or agave harvesters. I usually set these up when I
arrive in the community. These typically last an hour or so. We sometimes also
have to go back to the monitoring site to finish the agave survey if we didn’t
finish the day before. If we’re lucky, we’ll have a little down time before
having to head back to set up the cameras and monitor again, but more often
than not we’re not so lucky…
Interviewing an agave harvester about his
management practices. (Photo by Gregorio Navejar)
Talking with a community leader and learning where agaves
are found in the community. (Photo by Jose Juan Flores Maldonado)
Interviewing a former community leader.
(Photo by Sergio Aviles)
All in all, my fieldwork is a JAM PACKED endeavor. Between
each trip, we usually have two days back in the city to recharge and reorganize
everything, including ourselves. When I first started the fieldwork, I was
physically and mentally exhausted by the end of the first trip. I questioned
whether I was trying to accomplish too much, and how it would even be possible
to fit everything in. Now that we have all gotten more adept at the work (doing
the agave surveys, setting up the cameras, etc.) we have a good system going
and I am no longer as stressed about how much there is to do. It’s still a lot,
and the schedule of staying up so late and getting little sleep still pushes my
physical and mental limits, but I feel like we’re more of a well-oiled machine
now. I have about five more weeks left here, and I’m sure it will be busy but
fun!
A nice way to end this post: Some of the beautiful agaves and skies that come with this fieldwork.
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