Data Collection – Student Intern Hudson Berkhouse

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My name is Hudson Berkhouse and I am a senior Wildlife and Fisheries Sciences major at Texas A&M University.  One of the reasons I was originally drawn to this major was that it combines a thorough scientific education in many wildlife-related scientific fields with hands-on training and experience.  Accordingly, students seeking a degree in Wildlife and Fisheries Sciences must, at some point in their undergraduate years, fulfill an internship that is in some way related to their studies.  For my internship, I was able to work as a field technician and on several other tasks for Dr. Light, a professor of Mammalogy, at Texas A&M during the summer of 2015.

Student intern Hudson Berkhouse.

Student intern Hudson Berkhouse.

The field-based project I worked on was a biodiversity research project in South Texas based at several ranches owned by the East Foundation (  During my internship, I traveled with other field technicians to the ranches to collect data concerning the presence and abundance of small mammals.  Because most of the land in Texas is privately owned and therefore difficult to access for research purposes, this project is able to provide important data towards a better understanding of the distributions of wildlife spread across Northern Mexico and Southern Texas.

As I mentioned earlier, my team was concerned primarily with data collection on small mammals, or “smammals” as we affectionately referred to them.  Towards this end, our daily routine consisted of setting Sherman traps in the early evening when it had begun cooling off, retrieving those traps early the next morning before it got too hot, and collecting both data and specimens from the animals we had trapped.

Although every aspect of this process was interesting to me, I specifically want to describe the data and specimen collection process.  When we went out into the field to retrieve our traps in the mornings, we made sure to bring all equipment necessary for gathering data with us.  Collecting the data as soon as possible was important because it reduced stress on the animals, ensured that whatever specimens we chose to retain would be in good shape, and protected the accuracy of our data by reducing opportunities for human error.


Perognathus returns to the field after being processed.

Peromyscus returns to the field after being processed.

Some of transects where we trapped were intended to yield data only, whereas others were set with the goal of specimen retention.  Animals found in traps that fell into the former category were weighed, sexed, measured, and freed. During this process we took note of any obvious deformities or ectoparasites that could be found on the animal.  The most important data from these transects involved which species could be found at different locations throughout the ranch. The goal of the latter type of transect (where specimens were retained) was to collect a few specimens of each species, destined for preparation and preservation.  Accordingly, those animals belonging to species that had already been collected were freed, whereas members of the different target species were culled and preserved.  Throughout all of these steps it was impressed upon me that minimizing the stress each animal must undergo, whether they are to be freed or culled, is of the utmost importance.

Part of what made this internship such a valuable experience was the insight into field work it gave me, as well as a much better understanding of what it is to do scientific research in my field of study.  I also greatly enjoyed getting to know my coworkers in an arena outside the classroom.  As a result of my job that summer, I know and respect my fellow students more, and have a much better understanding of the professional aspects of my major.

Sherman trapping at the APC – Lauren Wimbish

During August, I went into the field to trap small mammals at the Attwater Prairie Chicken National Wildlife Refuge near Sealy, Texas. I spent August 19-21 at the refuge with two graduate students from the Light Lab who were collecting samples for their research. The purpose of this research was to examine the effects of invasive red imported fire ants on small mammals, ticks, and tick-borne pathogens. On the first night we arrived, we set out 60 Sherman live traps at each of four transects distributed across areas where fire ants were present and where fire ants were chemically reduced. The Sherman traps are small rectangular boxes that are baited with sunflower seeds and are placed on the ground with one end of the trap left open. When an animal enters the trap and reaches the other side where the bait is located, the trap closes. Sherman traps are live traps, which means no harm comes to the animal.  While putting our traps out, we also collect any ticks that crawl on us. That first night, we caught about 20 ticks! The ticks kept getting onto our clothes, which made it easy to collect them. The only downside to seeing so many ticks was that we had to thoroughly check ourselves to make sure none of the ticks latched onto our skin or got underneath our clothing. The next morning we got up at around 7am to go check the traps. Checking the traps early in the day is a necessity to prevent any trapped mammals from over heating and to avoid unnecessary ant predation.  That morning we caught nine mammals. We checked each of the nine mammals for ticks, weighed them, placed an ear tag in their ear for mark-recapture purposes (if not already tagged), took an ear biopsy for pathogen screening, and took a blood sample if they were large enough (so as not to negatively affect the health of the animal). After taking these samples, we released the animals back where we caught them.  Going through and checking the traps and taking samples only took a few hours, so the middle of the day was free time. I spent the day reading and talking to the staff at Attwater Prairie Chicken National Wildlife Refuge.  At around 6pm, we went back out and reset all of our traps for the night.  The next morning we went out and picked up all of our traps. We ended up catching eleven mammals that morning. We took the mammals back to our trailer where we were staying and set up a table to take samples from all of them.  One of the animals, which was a cotton rat, escaped from our grasps and went on the run. The little sucker was fast, but with teamwork we were able to trap the little guy and finish taking samples. After taking samples and releasing the mammals we packed up our stuff and headed back to College Station.


Mammal preparation at the BRTC – Stefan Hill

Hands down, the best job I have had while interning at the BRTC was preparing mammal skins for the collection.  Although I haven’t had much time to prep any skins on my own, I am hoping that will change in the last few weeks of my internship.   Of all the tasks given to me this semester, it is not only the most fun but has also been the most rewarding experience of my time here.   Prepping a mammal and providing a skin and corresponding skeletal material to the collections allows me a rare opportunity as an undergraduate to actually contribute to the scientific community –even if it is on relatively small scale.  Hands-on projects that require a certain degree of dexterity and finesse have always been my strong points so this was something I was eager to learn about from the beginning.   However, after a few sessions of sitting with Dr. Light learning on how to carefully remove the skins from a couple of different types of mice, I realized just how hard this can be.   Working delicately to remove the skin while preserving the fragile tail, nose pad, ears, and limbs of a specimen that weighs only a few grams proved more challenging than I anticipated.   I learned it is definitely a skill that takes a lot of practice before anyone becomes good at it.  Specimen preparation is somewhat of an art and working on this task gave me an appreciation for all the specimens currently in the museum that are so neatly stuffed and sewn together that they almost appear life-like.   From the start of my career as a Wildlife and Fisheries Sciences student, I was always told to give a lot of respect to the animals that gave their lives to science.  After viewing the work that goes into each specimen preparation, I gained a greater insight as to why that is.

Preparing mammal specimens for the BRTC collection.

Preparing mammal specimens for the BRTC collection.

Specimens are generally either collected from field research or are donated by private sources. The BRTC has several of these specimens that still need to be prepared and entered into the collections.  To start the process, a mammal is taken out of the storage freezer and left in the fridge or table to thaw out.  A solid frozen mouse would obviously be very hard to work with, so it needs to thaw and soften up before the skin can be removed.  Once the specimen is ready, we record the genus and species into a log book along with lengths of body, hind foot, tail, and ear, and approximate weight.  The next step is to determine the gender of the species by observing the genital region followed by collecting any potential ectoparasites in a vial by brushing the fur.   After these steps, the skinning process can begin and a small incision is made in the abdomen.   It is ideal not to cut too deep so you avoid cutting into the gut.   I made this mistake my first time when I accidently nicked the large intestine and had to deal with goop leaking out for the remainder of my prep.  Most of the work after this is done with your fingers and a probe to separate the skin from the body cavity wall.  Working outwards from the incision towards the hindlimbs, the skin is peeled back over the legs towards the foot until another small incision is placed at the foot to slip the limb out of the skin like a sock on the left side of the body. This results in the bones from the left limbs staying with the skeleton so future researchers can examine the bones from the specimen.  On the right side of the body, the bones of the hind and forelimbs are cut and kept with the skin allowing for research of the skin (toe pads, etc.).  Once the hindlimbs are removed, the tail sheath is pulled off the tail to release the tail vertebrate, and the skin is pulled back up over the forelimbs leaving the head for last.  The skin is pulled up over the neck and the tissue connecting the ear canal, eye socket, and nose pads are snipped to release the skin in what should hopefully result in an intact empty “skin suit”.   The skin is then carefully stuffed with cotton to create a full body effect, sewn up, and pinned to a rack to dry.  The skeleton is given a tag and saved in the freezer until there is room in the dermestid colony to process the skin.  The entire process can take several hours, and for a novice can be incredibly frustrating at times.   Once a mistake is made, it is very difficult or impossible to undo.  Regardless of the challenges behind it, I still immensely enjoyed learning the skinning process and was glad to contribute even just a handful of specimens.

Stefan Hill, sorter of tissues

Sorting and documenting tissue samples.

Sorting and documenting tissue samples.

One of my main projects during my internship at Texas A&M University’s Biodiversity Research and Teaching Collections (BRTC) was sorting through and organizing a collection of tissue samples from past research by Dr. Ira Greenbaum. These tissue samples were primarily harvested from a variety of Peromyscus species over decades of research. Totaling over 7,000 combined liver, heart, kidney, and testicle samples, the collection had been stored inside freezers in Dr. Greenbaum’s lab for some time, until those freezers started to fail.  Luckily the BRTC was able to take in these tissue samples and continue to preserve them by placing them within the Genetic Resources collection.   Notably, the skins and skulls from which these tissue samples were taken are already included within the Mammal Collection. Therefore, obtaining these tissue samples greatly benefits the collections overall as now we have all samples associated with each specimen. As one can imagine, sorting through all these frozen tissues is a huge and somewhat numbing (literally) task. Fortunately for the staff at the BRTC, there is an army of undergraduate interns such as myself that will work on such projects.  The task may have been simplistic in itself, but it gave me some insight to the efforts that are required at times during real scientific research.

Organizing the Greenbaum tissue collection involved taking the tissue samples out of the original cardboard storage boxes, placing them into new plastic vial storage containers, and recording their information into an excel tissue spreadsheet where they could be easily located. These new containers were organized into a 9 x 9 grid system capable of holding up to 81 individual vials; columns were labeled A through I and rows labeled 1 through 9. Each new container was numbered and entered into the tissue excel file on an individual spreadsheet that had the empty cell slots organized A1-I9 ready for vial placement.   Written on the side of every vial contained the initials of the researcher, followed by that collector’s collector number and a letter designating its tissue type.  This information would be recorded into the spreadsheet alongside the cell number giving each tissues’ specific location.    After organizing all the tissues from the storage into new containers, the next step was to cross reference the organized vials’ collection ID with another excel spreadsheet from the Mammal Database that contained the specific information about each individual specimen from which the tissue came from.  The purpose of this cross-listing was to record that a specimen cataloged in the Mammal Collection did indeed have a tissue and note the tissue location (box and cell slot). Although time consuming, the overall process was fairly straightforward and once I got into the rhythm of creating new excel sheets for each tissue box, reading the tissue information, and entering it into the excel file, I was able to fly through the process. My knowledge of the Excel program definitely increased as I discovered faster keyboard shortcuts to enter the data at a much more efficient rate. It wasn’t exciting work but by listening to music, TED Talks lectures, and audiobooks, I was able to stay focused and relaxed enough that time went by much faster. The biggest challenges and frustrations involved with this project was merely trying to decipher some of the written information on the vials. A combination of illegible hand writing and non-permanent ink made reading a fair number of tubes almost impossible.  I would either have to look for patterns in the numbering system of how they were originally sorted to deduce what was written or simply record UNREADABLE in the Excel file.

After accumulating several dozen hours doing this project, I often wondered what the overall purpose of this project was. Then about halfway through the semester, I happened to stumble upon a magazine article highlighting the importance of biodiversity collection museums. The author pointed out that they play an important role by tying together a number of scientific fields including genetics, population studies, migration patterns, evolutionary history, and taxonomy that can be used to further benefit the goal of conservation. These tissue samples that I had been sorting were a contribution to that direct effort.  They can be used by future researchers for generations to come for a variety of studies to further advance the field of biodiversity.

Small mammal preparation at the BRTC

Noel Lyon – BRTC intern

One of the more hands on tasks at the Biodiversity Research and Teaching Collections (BRTC) is to prepare scientific specimens to be cataloged into the mammal database. Scientifically prepared skins held in natural history collections provide morphological and physical characteristics of individuals and the species as a whole. These data can illustrate how individuals and a species can vary through time and geography, creating a snapshot of a species in a given time and location. Furthermore, additional data such as the life stage, tissues, and parasites gathered during the collection of a particular specimen can also provide researchers with useful data.

Baiomys taylori specimen prior to processing.

Baiomys taylori specimen prior to processing.

During my internship, I prepared several specimens in the order Rodentia. I did not have trouble skinning after receiving excellent instructions provided by Dr. Light. But stuffing specimens proved to be a challenge. Skinning of all mammals follows a general procedure that can be altered depending on the desired outcome (pelt, museum specimen, meat).  A cut is made up the ventral side of the body from just above the urogenital area to about the forelimbs. This allows room for the skin to be worked off the limbs and body using a counter pull system. This system involves pulling the body one way while simultaneously pulling the skin in the opposite direction. Extra care is taken around the limbs and tail to prevent the skin from tearing. Similarly, the face needs to be worked off of the skull very carefully to ensure that the nose, ears, and eyes remain intact. The bones that comprise the digits and feet on the right side of the animal, as well as the baculum for males, are kept in the skin to maximize the amount of information that the specimen provides.

Wire is traditionally placed in the tail and limbs to ensure that these portions of the specimen are laid out straight. Small specimens such as mice require very thin wire, which unfortunately is easily bent. I found inserting the wire into the right forelimb and hindlimb to be the most difficult and sometimes frustrating part of preparing a specimen. Wire is inserted in the feet so that it sits between the bones and the skin. There is very little room in this area, and inserting the wire requires gentle poking and manipulation to slide into place. Cotton is often wrapped around the section of wire that sits in the area of the legs vacated by the femur and tibia in the hindlimb, or the humerus, radius and ulna in the forelimb. This is done to give the prepared skin as much of a lifelike appearance as possible.

Cotton is also wrapped around the wire used in the tail. The process of inserting the wire into the tail is much easier than in the limbs. However, the cotton must be wrapped very tightly around the wire or it will slip and bunch up which makes insertion impossible. Additionally, the thickness of the cotton must taper towards the tip of the tail, with it being widest at the base of the tail.

Scientifically prepared Baiomys taylori ready for drying, fumigation, and installation into the mammal collection.

Scientifically prepared Baiomys taylori ready for drying, fumigation, and installation into the mammal collection.

Cotton is also used to stuff the body cavity and head of the animal. Cotton has to be placed just right in the nasal region of the animal, otherwise it looks very odd; for rodents, you want the specimen to have a pointy nose just like in life. I found the aid of forceps crucial in this step. After estimating the amount of cotton needed and cutting it into the shape of a triangle, I would fold up one corner very tightly and grasp it with the forceps. After carefully placing this end into the tip of the animals nose, I would release the forceps and the cotton would expand and fill in the nose. After that, I would fold the rest of the cotton into the body and sew up the incisions made during skinning. This step often took the longest, as removing and manipulating the cotton was necessary to ensure that body proportions were more or less realistic, and dorsal and ventral surfaces were smooth. The final step is to pin the specimen to a piece of foam to dry. This step requires an artistic touch to make the animal appear as lifelike as possible. The nose, head, and tail are lined up while the legs are stretched out pointing directly to the front and rear of the animal. Lastly, brushing the fur and minor tweaking can make a huge difference in appearance.

With biodiversity declining around the world, properly prepared and cared for specimens are becoming increasingly valuable. As species become scarce, studying them becomes more difficult. Natural-history collections provide samples of species that may otherwise be unobtainable. Data gathered from prepared skins may provide insight into why a species is in decline in the wild, as well as how individuals vary over time and space.

Stefan Hill, Dermestid Care Level: Expert

Skeletonized specimen being removed from the Dermestid beetle colony.

Skeletonized specimen being removed from the Dermestid beetle colony.

My name is Stefan Hill and during my final semester as an undergraduate at Texas A&M University, I had the fortunate pleasure of interning at Texas A&M University’s Biodiversity Research and Teaching Collections (BRTC).   It was the busiest semester I have had to date in my entire college career, but the experience I gained as an intern in these short few months have been one of the highlights of my academic study.  I learned the ins and outs of how the specimens in the collection are selected, prepared, and managed for long term storage to promote the process of biodiversity conservation.  One of these processes that I was directly involved with included the care of the dermestid beetle colonies used to clean animal skeletons.  These beetles will eat the flesh off a skeleton and after a few days of chowing down, will leave a perfectly intact skeleton.  It was pretty fascinating to observe this process first hand.  I was able to witness all kinds of animals being placed into these colonies and, after only a matter of days, coming out looking completely unrecognizable.  From watching deer, bear, and alligator heads to whole shark and squirrel bodies being consumed was a pretty cool experience overall.

The procedure of specimen preparation that I was involved in went in this sequence: Specimens would be skinned and tagged and placed in a freezer until there was room for them in the beetle colony.   A metal tag with an ID number was then matched with the specimen number as a secondary means to keep track of each individual specimen.  This is especially important because the beetles tend to move everything around and the skeleton becomes dismantled while the bugs are feeding. Once removed from the bugs, the skeletons are soaked in a 3:1 ratio of water to ammonia hydroxide to further clean the bones of oils and organic matter for 12 hours.   If left to soak any longer, the chemical can actually do damage to the bones so it is crucial to remove them within this time frame.  From the beginning I was warned that ammonia hydroxide is a very strong irritant and is incredibly volatile.   Therefore, when using ammonia lots of ventilation as well as eye protection is needed, otherwise your throat, nose, and eyes will become horribly agitated by the fumes.  Once removed from the chemical solution, the skeletons are air dried for 24-48 hours, boxed up, and placed into the freezer for another 7-10 days for a final fumigation step.  After freezing, the specimen is assigned an identification number and installed into the collection for final storage.

The only real downside working with the beetles was the smell.  The colonies were located in a separate shed several hundred feet behind the BRTC building for good reason.  These things stank like no one’s business.   The decaying carcasses combined with the beetle excrement and substrate creates a very strong, pungent, unique smell.   It’s not necessarily a smell that makes you gag or get sick, but it’s still not all that pleasant to work with for long periods of time – mainly because it sticks to your clothes and is very noticeable to anyone else afterwards.   I learned that lesson pretty early on after working with the beetles one afternoon and then biked back to campus on a particularly hot day for my next class.   Sitting through a 50 minute lecture radiating a funky, mutated B.O. while my classmates conspicuously wrinkled their noses was enough ostracism for me to start bringing a change of clothes any time I worked with the beetles.

Mammal Collection at the BRTC – from the eyes of an intern

Noel Lyon – Spring intern 2015

The mammal collection at the Biodiversity Research and Teaching Collections (BRTC) contains thousands of scientific specimens. These include alcohol specimens, skeletons, skulls, and scientifically prepared specimens. One of the greatest dangers to skeletons, skulls, and alcohol specimens is being dropped, whereas scientifically prepared specimens are threatened by insect pests. One of the many insect pests detrimental to preserved animal skins is the cigarette beetle. Larvae feed by burrowing into the skin, which can damage or ruin a museum specimen. Feeding by adults on the proteins within the skins can also ruin specimens. Adults are small, about 2-3 mm in size, and are reddish brown in color. The eggs of cigarette beetles are coated with a layer of B vitamins when they pass through the oviduct upon laying, which larvae can utilize as a food source (Cabrera 2001). Females lay 10-100 eggs in the food source and larvae typically emerge in 6-10 days (Cabrera 2001). The life cycle of the cigarette beetle ranges from 40 to 90 days depending on temperature and availability of food (Cabrera 2001). With the large number of eggs produced by each female in addition to their relatively long life cycle, an unchecked infestation of cigarette beetles has the potential to destroy many valuable museum specimens and the data they provide.

Mammal Range1

The mammal collection at the BRTC

An important, although seemingly dreaded task, is to thoroughly search every case in the collection for signs of a cigarette beetle infestation. I spent a good deal of time inspecting hundreds, if not thousands of specimens for signs of beetles. Opening drawers and looking for beetles simply isn’t sufficient. Every specimen must be removed and checked. The average case holds about 10-15 drawers, and depending on the size of the animals, one drawer can hold up to 30-40 specimens. If I found a live beetle, then the case was fumigated using ethyl acetate to kill the beetles and remove the infestation. Whenever I came across the body of a dead beetle, I pinched it between two fingers to estimate its age. If the beetle was juicy, than it was relatively fresh, and every specimen was examined extremely carefully to determine if there was an active infestation. If an infestation was found, the case was fumigated. If the beetle crumbled to dust when I pinched it, than it was old, and the bug and specimen debris was vacuumed out. In addition to looking for signs of insect damage, I also replaced or added mothballs to the jar lids that are in every case to deter cigarette beetles and other insect pests. Lastly, I also recorded my findings on a log kept inside each case to monitor infestations over time. Thankfully, I did not find any infestations.

Mammal Range2

Typical drawer of specimens in the order Rodentia.

A great deal of information is contained with each specimen housed within the BRTC. For mammal specimens, this information includes collector and collector number, the location they were collected, any measurements taken at the time of collection, and sometimes other tidbits such as the cause of death and whether the animal was reproductive. This information is included in the database and on tags associated with each specimen. However, these specimens and their information lose their value if the specimens are eaten or destroyed by cigarette beetles. As I went through the drawers and cases, I read the information contained on many of these tags, and I was amazed at the age of some specimens. Some are from the 1920’s and 30’s and are in excellent condition. This would not be possible if not for vigilance by many people looking for cigarette beetle infestation signs over time. I was not the first, nor will I be the last person to check the cases. I can’t say it was the most exciting thing I’ve ever done, but I did learn a lot more than I thought I would.

Literature Cited

Cabrera, B.J. 2001. Cigarette beetle. Entomology and Nematology. University of Florida.



Libraries of Life –

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Excellent article from NY Times about collections!

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Museums: The endangered dead : Nature News & Comment

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Museums: The endangered dead : Nature News & Comment.

Getting the Bats in Order

Another bit from our WFSC undergraduate intern Lauren Wimbish, this time she’s in our collection of bats organizing their skins and skulls-


Lauren Wimbish proofing the order of bat specimens in the collection.

This past June I spent many hours reorganizing the bat collection at the BRTC. Bats are mammals that belong to the Order Chiroptera, which is the second largest mammal group (only rodents belong to a more diverse Order). They are also the only mammals that are capable of sustaining true flight. The collection consists of many different species of bats from all over the world, but mostly the specimens are from the Americas. Reorganizing each case consisted of going through each drawer and making sure the specimens were in alphabetical order by family, genus, species, and geographic locality. Each drawer would contain at least one family of bats. The bats within that family were alphabetically placed by species name and geographic region within that same species. Usually, each case had about 12-15 drawers and would take roughly an hour to go through. Most of the specimens I organized were fairly small and did not vary much in size. While shuffling through the bats I would always put my headphones in and enjoy some music to help give a relaxing work setting.  On days when the air conditioning was struggling to cool the building this was especially necessary. Texas summers can be pretty brutal, even inside. On a few occasions my work lead me outside and I would have to tough it out in the Texas heat.