The wild-er side of Texas!

Well, I've posted pictures of scenery, other people's wildlife projects, and even Florida wildlife!  But believe me, there is more to Texas than bears, lions, pronghorn and mule deer!  While those animals (commonly known as big game species) may cause more excitement in the hearts and minds of those who get the privilege to see them in person, there is a whole other wildlife world that is usually given much less attention by those not directly interested in them.  I'm talking about small mammals - mostly rodents, who unfortunately get a bad reputation due to their tending to be rather destructive in large numbers.  But putting your opinions of the stereotypical giant NYC subway rats and house mice aside, these animals can be a lot of fun to work with in the wild!  Another sometimes overlooked animal group are reptiles and amphibians (collectively known as herpetofauna - aka herps).  But, if any of you know my boyfriend, Bob, you'll know that it is almost impossible for me to overlook this group!  :)  Down here in Texas the herps are pretty abundant - especially the rattlesnakes.  In fact there are some sub-species of snakes that only occur in the Trans-Pecos region of Texas.  (For example, there are a few different sub-species of the copperhead in North America - northern copperhead, southern copperhead, and Trans-Pecos copperhead.)  The hot and dry environment is perfect for several species of snakes and lizards.  Starting this month, when I do my small mammal trapping and bird surveys, I will also be starting herp surveys - meaning I'll be looking for all those snakes and lizards out there (frogs and amphibians are also in the herp group, but since the Trans-Pecos is so dry, I am not expecting to find too many of those)!

Anyway, I'll stop with all the writing and get into the pictures.  I have A TON of small mammal pictures since I usually try to take a couple pictures of every small mammal I catch - which has been a lot so far!  I will try not to overwhelm you with small mammal pictures, but maybe I'll help some of you rethink your possibly negative opinion of rodents and prove that not all rats and mice are gross and a nuisance!  :)

Ok, I think I am going to try to group the different kinds of small mammal together so that it is a little more organized... and easier for me to keep track of!  You'll see a lot of these different species look almost exactly alike!  So I am going to group them by Genus.  In taxonomy each species belongs in different groups starting broad (for example: Class Mammalia includes ALL mammals) to more specific all the way down to an animal's specific epithet which includes the genus and species name (also called scientific name), and is always in italics when typed (or underlined when hand written).  The species name is the most specific taxonomic level (for example, the specific epithet or scientific name of an American black bear is Ursus americanus - Ursus being the genus name, and americanus being the species name). Ok, sorry for the brief lesson in taxonomy!

Before I get into the genus groups... I wanted to put this picture in here to show you how I get a hold of the critters.  First I shake them out of the trap into a big zip-lock bag.  Then I get them to put their noses in the corner of the bag so that I can use one hand to hold them still and the other hand to reach in and grab them by the scruff of their neck.  They are usually pretty unhappy and squirm around a lot, which means I let go of several individuals before I finally got the hang of keeping a good hold on them!  Grabbing them in the right place behind their heads also keeps them from turning around and chomping down on one of my fingers!

Ok, here we go.  First up... genus Peromyscus (Deer Mice)!

I believe this is a Peromyscus maniculatus (American Deer Mouse).  Apparently he was hungry when I let him go because he just stayed there and nibbled on some bait that was on the ground :)

Here I am taking measurements on a mouse.  As I mentioned earlier many Peromyscus species look A LOT alike so it is important to take certain measurements on each animal caught since that can help determine the difference between species.  I measure the ear, tail, hind foot, and full body length.  I also determine whether it is male or female.

This is another American deer mouse.  I just thought it was cute that his fur was all ruffled up from me handling him :)

Here is another American deer mouse.  You'll notice this one has some orange colored fur along it's sides.  A lot of other Peromyscus species have that, so unfortunately it can't always be used as a distinguishing feature!

Here is a Peromyscus leucopus (White-footed Mouse).  You can see it's white hind foot in this picture.  Other Peromyscus species have white feet too, so there are still other features I need to look at to determine if this is in fact a white-footed mouse - which I decided it was.

These pictures are showing one way to help tell the difference between the white-footed mouse and the american deer mouse. The white-footed mouse (left) has more white on each hair making it's white belly fur appear to be almost purely white, whereas the deer mouse (right) has more black on each hair (the part closer to the body) making  it's belly fur look darker.  Again, this alone is not a way to tell the difference between these species, but combined with other features could be helpful.  Are you starting to realize how difficult it could be to identify these little guys??

Here is another species of Peromyscus - Peromyscus eremicus (Cactus Mouse).  This mouse looks pretty much just like the others, which is why I decided not to include a full body picture.  But, this is one species that has a fairly easy way to identify - you'll notice in the picture that the sole of its hind foot has no fur on it.  All the other species I have showed you so far do have fur on their hind feet.  A naked hind foot is one defining characteristic of Cactus mice.

Ok, enough of those... I think Peromyscus is the hardest group to tell difference between species! So, next up...  genus Dipodomys (Kangaroo Rats)!

There are only 2 species of kangaroo rats in this part of Texas: Dipodomys merriami (Merriam's Kangaroo Rat) and Dipodomys ordii (Ord's Kangaroo Rat).  So far all the kangaroo rats I've caught have been Merriam's kangaroo rat, like the one in this photo.

Telling the difference between Ord's kangaroo rats and Merriam's kangaroo rats is actually pretty easy.  Merriam's kangaroo rats only have 4 toes on their hind feet (like the picture on the right).  Ord's kangaroo rats have 5 toes on their hind feet.  As you can see in the picture on the left, I caught a kangaroo rat with only 3 toes on one of it's hind feet!  It was a Merriam's kangaroo rat, but I thought it was interesting that he only had 3 toes on that one foot.  I actually caught this one a couple times, and could tell it was him because of his 3 toes :)

Here is another photo of a Merriam's kangaroo rat.  It's a little hard to see in the picture, but they also have very long tail's that have long fur at the tips (called a "crest").

This was the last catch of the day on one of my trap days and it just so happened to get REALLY windy right when we were about to release this kangaroo rat.  I guess he wasn't ready to face the wind yet, because he decided to take cover under me instead!  This actually happens a lot when I release other mice.  They seem to go for the first sheltered area, which a lot of times ends up being under me or my backpack.  Sometimes, even if I move they won't leave... not the smartest creatures I guess.  :)

Next on the list... genus Sigmodon (Cotton Rats)!

There are 2 species of cotton rats in this area of Texas: Sigmodon hispidus (Hispid Cotton Rat) and Sigmodon ochrognathus (Yellow-nosed Cotton Rat).  An easy way to tell the difference between these two is again, to look at their hind feet.  The hispid cotton rat (right) has all black soles on their hind feet.  The yellow-nosed cotton rat (left) does not have black soles.  As you can guess, the yellow-nosed cotton rat also tends to have a more yellow colored nose and body.  Still, the hispid cotton rat can have similar coloring, making it difficult to use that as the only means of identifying the species.

Guess what!  These are two different species!  Could you tell??  I sure wouldn't be able to just from these pictures!  The one on the left is a yellow-nosed cotton rat, which makes the one on the right a hisipid cotton rat!  Now you can see why you shouldn't use color of fur alone to tell the difference between these two species :)

Ok, moving right along... genus Perognathus and Chaetodipus (Pocket Mice)!

I'll be honest and say that I do not know my pocket mice too well yet, because I have only caught a few. But now that it is warmer, I'm sure I'll start catching more of these (I think they hibernate during the winter months).  I believe the one above is Chaetodipus nelsoni (Nelson's Pocket Mouse).  Pocket mice are different from deer mice (Peromyscus) in that pocket mice have much smaller ears and bodies, and most have a crest on their tail similar to kangaroo rats.  If you look at the tail of this mouse all the way until it goes out of the picture, you can see the very beginning of the tail crest.

I think this is a Perognathus flavus/merriami (Silky/Merriam's pocket mouse).  Sometimes two species are so alike on the outside that it is pretty much impossible to tell the difference - this is on of those species.  Silky pocket mice and Merriam's pocket mice are two different species but look identical on the outside.  Usually there are skeletal features that can distinguish between species such as these, but since I am releasing everything I catch, I cannot rely on skeletal features to identify which species it is.  These species do not have crests on their tail, which help identify them from other pocket mice.

 I'm not positive about this one yet, but I am pretty sure it is a Chaetodipus intermedius (Rock Pocket Mouse).  This species does have a crest on it's tail (similar to Nelson's pocket mouse pictured above), but after looking at the measurements I took and some other differences such as fur color and presence or absence of a specific type of fur/hair called bristles or spines (usually longer than rest of fur and different in color) I decided it was a rock pocket mouse.

Alright, last but not least... genus Neotoma (Wood Rats)!

Sorry, I know I look kind of goofy in this picture... but I was excited!  :)  This is the largest small mammal species I have caught so far!  It is a Neotoma micropus (Southern Plains Wood Rat).  You'll notice in the picture that it's tail looks pretty short.  There was actually a lot of the tail missing from a previous injury, so it should actually be longer.  I was pretty excited about this catch!  As soon as I picked up the trap I knew it was something big!  This weighed about 100g more than the largest of the smaller species I've caught so far, which is a big jump!  Anyway, we took lots of pictures of this while it was still in the bag, just in case I couldn't hold on to it once I got it in my hands.  Luckily she was very docile and let us do what we needed before we let her go.  I also think she had some babies waiting for her somewhere because she was lactating.  I'm hoping to catch more of these now that it's warmer!  I'm definitely going to have to invest in a good pair of gloves first though!

A close up of the wood rat.  A little different from your typical nuisance city rat (which by the way are actually Norway rats and VERY invasive - meaning they are not native to North America at all).  I actually think this wood rat was very pretty as far as rats go.  :)

Well, I know that was a TON of information, but hopefully the pictures made it a little more interesting.  I hope everyone who's reading now has a little better idea and understanding of some of the things I do when I say I'm "out in the field."  Even though I catch a lot of the same species, I still get excited every time I see a closed trap!  Now that it is warmer I have a feeling I'll be seeing some new species, and I'm pretty excited about that!  I'll definitely keep you posted on what new critters I see and/or catch!

I didn't expect this post to be quite so long - I was actually going to put in some of the pictures I've captured on my trail cameras and some pictures of herps... but I guess that just means I have to write another post soon!  I will be out in the field this weekend and next weekend (Thurs. - Sun.) starting my second trapping season at Elephant Mountain Wildlife Management Area (aka EM).  I have an exam and a first draft of an annotated bibliography (composed of over 40 article summaries on black bears!) due in between those weekends so I will definitely be busy the next couple of weeks!  I'm sure the time will fly by.  I can't believe it's almost April already!!!  What happened to the first 3 months of the year?!?

Anyway, as always... thanks for reading!

Until next time, Laura :)