Coatis and programmers in the desert

An update from the May Portal trip (which occurred immediately after my Giant Kangaroo Rat foray):

Recent USU graduate, Ben Morris, who had been working with the Weecology lab for the past few years, finally made it out to our field site, just before starting his Ph.D. with the Hurlbert lab at UNC! Ben spends most of his time on the computer being a ninja at utilizing ecoinformatics and big data, but he proved quite worthy in the field. We also saw a coati in the middle of the desert. Not sure what it was doing out there, but it didn’t look too happy… (sorry, no coati pictures to prove it!)

Ben weighs a grasshopper mouse.

Ben measures the hind foot length of a kangaroo rat.

Portal Squee: Nesting Cactus Mice

This post is way overdue, but the photos are so cute that I couldn’t help myself. Back in March 2012, when Glenda Yenni, Xiao Xiao and I travelled to Portal to count the winter plants, we discovered cactus mice (Peromyscus eremicus) nesting in a box that we were using to hold firewood. When we took the wood out of the box, there was a flurry of activity and a big fluffy nest inside!

A scared cactus mouse runs around the box.

What was even more interesting was that the nest had a two (eartagged!) adults  pair with 2 different ages of offspring! There were 3-4 subadult mice along with 2-4 teeny tiny juveniles (it was hard to count in the dark with all the running around). The juveniles were small enough (although they did have hair) that they remained attached to the nesting female when she ran out of the nest.

I mentioned this to Karen Mabry, who sometimes helps out at Portal, and she suggested that although not much seems to be known about Peromyscus eremicus, they may be “more monagamous” than some other species mice. Some other Peromyscus species are known to be socially and genetically monogamous, and have sometimes been confirmed as nesting with sisters (rather than a male-female pair), which could potentially explain why there were 2 different ages of juveniles in the nest box.

Female cactus mouse peers out of nest.

(Photo credits: Glenda Yenni)

Through the (desert) looking-glass

Between the March and April Portal trips, I fell through the looking-glass into the Namib Desert. Everything there felt so eerily similar to southeastern Arizona, yet also strikingly different. Compare the below photos from the Spitzkoppe, a large granite massif of volcanic origins in the western Namibian Desert, and of Portal (the Chircahuan mountains also are eroded granitic domes with volcanic origins!).

Spitzkoppe, the “Matterhorn of Namibia”

Chiricahua Mountains, with the Portal Project in the foreground, October 2007

Although I didn’t actually get to see or handle any small mammals while visiting the Spitzkoppe, there are diverse rodent communities in the Namib desert, as there are in southeastern Arizona.

Unidentified small mammal hole, Spitzkoppe.

Banner-tailed kangaroo rat (Dipodomys spectabilis) hole, Portal.

Both Portal and the Spitzkoppe are arid grassland deserts on the edge of small, isolated mountains. Both have acacia shrubs with white thorns, and both abound with spiny and woolly vegetation. However, Namibian shrubs are inhabited by weaver bird nests rather than cactus wren nests (but both are roundish with small, circular openings).

Weaver bird nests in an acacia, Spitzkoppe.

Cactus wren nest in a cholla, Portal July 2009

The large, eroded granite rocks are similarly enticing, easy to climb and explore, and also host populations of small cryptic scorpions, spiders, rodents, and lizards, although in Namibia, unlike Portal, you are likely to see groups of hyraxes. The surrounding plains are home to a variety of antelope and grazers (such as springbok, hartebeest, zebra, warthog and rhino, to name a few) rather than Coues white-tailed deer or javelina.

A very cryptic Agamid lizard, Spitzkoppe

Texas Horned Lizard, Portal (Photo courtesy of R.P. O’Donnell, May 2011)

Hyraxes are NOT large rodents, but are actually more closely related to elephants! These are Rock Hyraxes (Procavia capensis).

Euphorbia virosa, “poison tree”, in the Spitzkoppe. Although it looks similar to organ pipe cactus, this is NOT a cactus, but a member of the spurge family.

Experiencing another, similar desert was an amazing experience which I hope to repeat, but I eventually crossed back to my hemisphere and the right side of the looking-glass, where my world was again familiar and the research at Portal was waiting for me to return…In late April, we captured our first pack rat (Neotoma albigula) since Fall 2009 !

Sarah documenting the Return of the Pack Rat.

There was no rain between March and April, so the vegetation was all going to seed and the soil was dry and dusty again. Rodent abundance and diversity continues to rise, however, so they must be caching all those valuable little seeds!

Nic Kooyers, a graduate student at Washington University in St. Louis, came to learn about the project and look for unique desert vegetation. Nic is especially interested in the evolution of plants that display variation in the production of secondary compounds, but he really liked the rodents, too.

Nic weighing an Ord’s Kangaroo Rat (Dipodomys ordii).

 

Portal rodent-plant extravaganza: Day 4

My lab mates, Glenda and Xiao, and I left early Saturday morning to drive from northern Utah to Portal Arizona. It’s about an 18 hour drive, but the scenery is beautiful, so it’s not that bad. We stopped at Coral Pink Sand Dunes State Park along the way, near the Utah-Arizona border. I’d highly recommend a stop!

Between Sunday and Tuesday night, we repaired our trap shed, trapped 127 rodents and counted plants on 13 of the 24 plots. We still have a lot of work to do… Here are a few photographic highlights from the data collection so far:

A desert pocket mouse sits near some very scenic poppies.

Xiao and Glenda count plants on a poppy-filled plot.

Bees really dig the Gordon’s bladderpod (Lesquerella gordoni).

February trapping

I traveled to Portal again Feb 18-20, this time meeting a crew of people from New Mexico State University.

Chaetodipus pencillatus, desert pocket mouse.

Karen Mabry has been especially helpful for finding volunteers and keeping Portal going through our lower-funding times. She also studies rodents, with most of her work with Peromyscus at the Quail Ridge Reserve in California. So she was excited to see that diversity at the site is returning quickly–we’re back up to 10 different species!–and that we caught several incredibly cute cactus mice (Peromyscus eremicus). We also continue to catch the harvest mice (Reithrodontomys megalotis and montanus), which was fun for visiting grad student Katie Smith, who studies the endangered salt marsh harvest mouse in California.

Katie Smith holds a small harvest mouse. Photo by J. Smith.

With so many experienced rodent-trappers, we were able to get through all the captures pretty quickly and leave extra time in the afternoon for Jane Smith to take some measurements for her project. Also an NMSU grad student, she has been investigating the effects of small mammals on soil organic carbon, using the experimental manipulations at our site.

I’ve never captured so many birds before, but 11 of our 110 traps this month has birds in them rather than rodents! Pictured above is a white-crowned sparrow (photo by J. Smith). These were most common, along with black-throated sparrows and a canyon towhee.

Katie Smith, Kristin DaVannon, Sarah Supp, and Karen Mabry (left to right) process the rodents from the exclosure plots. Photo by J. Smith.

(Above) Kristen, an undergraduate student at NMSU, learns that handling rodents is fun! Photo by J. Smith.

The winter plant census is fast approaching, and many flowers were already beginning to bloom in February! I’m optimistic that it will be another beautiful spring. Keep posted for the plant update!

Poppies are already in bloom! Photo by J. Smith.

Lupinus coccinus.

Holiday season with the Portal rats

Trapping at Portal is usually done on the weekend closest to the new moon. This is done for a number of reasons: 1) trapping at the same time each month lends consistency to our methods, and 2) evidence suggests that rodent may be most active outside of the nest under the cover of the darkest time of the month (but then again, maybe not). This year, the new moon fell on the day after Thanksgiving and again on Christmas Eve. As much as I enjoy handling rodents, I pushed back the monthly Portal trips to the first (Dec 2-4) and third quarter (Dec 16-18) of the lunar calendar.

When the temperatures drop, many of our smaller species disappear for the winter as they enter torpor to save energy and remain warm in their burrows. Although larger species, such as the kangaroo rats and grasshopper mice stay active year round, they are still susceptible to cold desert nights, which commonly dip as low as 20 F in the winter! Getting wet, even a little bit, when it is so cold can kill even these larger individuals. So when I arrived in Arizona on Dec. 2nd to see rain clouds in the sky,  I knew that trapping that weekend was just not going to happen.

Given the total lack of rain last winter in southeastern Arizona, and the nasty fire season they experienced this past summer, the rain is much needed. So although we weren’t able to set out traps, Tim Bean, visiting from UC Berkeley (where he studies the endangered giant kangaroo rat!), helped me with some site maintenance activities.

Erosion around the gates in our fences has continued as the rain falls, so we took advantage of the damp soil to rebuild little ‘ramps’ for the rodents to use to ensure that immigration and emigration from fenced plots can still happen.

While walking around all the plots, we also filled in holes that seemed to go under our fences. Here, a badger has successfully created a superhighway into one of our total rodent exclosure plots, right under the bottom of the buried wire mesh.

Here, Tim valiantly fills in the hole. Not a very good substitute for getting to see cute kangaroo rats, but it had to make do.

Germination has already begun, and if the rain keeps up, there should be a lot of vegetation this spring!

For the second December trip, I brought along ASU researcher with the CAP LTER, Julie Ripplinger, and we were lucky enough to be able to set traps one night, despite rain clouds lurking in the sky.

Julie is pictured here holding a cactus mouse (Peromyscus eremicus), which seem to be relatively abundant right now! We caught nearly all of them in pairs, one trap right next to the other and nearly all were in breeding condition. Cactus mice may breed year-round if conditions are right. They are also quite pretty mice with their orange-y sides, large ears, and very soft fur.

In addition, we continue to catch a solitary Bailey’s pocket mouse (Chaetodipus bailey); the species that was once our most dominant seems to be hanging around nearby…

Rain clouds hung around all day on Saturday (Dec 17) so we erred on the side of safety and didn’t set traps on our final night. Instead we completed more plot maintenance, this time focusing on stabilizing our trap shed. The shed is one of those snap-together plastic outdoor sheds which works fine for our purposes, but from time to time begins to fall apart and needs snapped back together. During the past two weeks, something dug a large hole underneath so it was completely destabilized. I wanted to take it completely off its cobbled-together rock base and rebuild it, but Julie stopped me when she saw the tail of a mojave rattlesnake poking from underneath the shed near my hand. Again deciding to err on the side of safety (snakes often overwinter in large groups, called a hibernaculum), I satisfied myself with carefully filling in the part of the hole I could see and stabilizing the roof of the shed.