Sherman traps (not placed yet), next to some pocket-gopher mounds:
The largest box trap that we placed on top of a small hill with lots of woody debris around it. We baited it with peanut butter and cat food, hoping to catch some larger mesocarnivore (which unfortunately did not happen):
Fence runs with box trap and pit traps at corner of the fences:
While setting traps we also looked for signs of mammals. Here are some raccoon tracks we spotted in a wash:
Also, our professor had me helping his ornithology students look for and ID birds while we set mammal traps. At one point we spotted a Cooper's Hawk which had nailed some small animal and was ripping it up on a limb. After reviewing my photos later on, it looks like its prey was a woodrat:
There is a small pond at the preserve that sometimes has waterfowl on it. While setting traps along the shoreline, we spotted a pair of Wood Ducks (poor photo below, due to the fading light):
After setting traps we met back with the herpetologists who had found a common kingsnake (Lampropeltis getula) and were processing it (taking measurements and marking it before releasing it). Notice in the last photo how well the light-colored bands on its skin blend in with the dead, curled grass:
Following the snake release we gathered around one of the herpetologists, who happened to have a cool radar attachment to her laptop used for recording echolocation signals of bats. Periodically we picked up the signals as she pointed the radar towards the creek. There was still a tiny amount of light against the almost black sky, but we could not see any bats flying around (just the seismograph-looking readings on the computer program). During this time, someone went off to take a leak and heard something rustling around in one of the Sherman traps. After taking the trap back to the truck, we waited for our professor to return from attempting to set mist nests for bats. When he got back he got a bag to place around the mouth of the trap and emptied it out to find a deer mouse (Peromyscus maniculatus). He then cornered it in the bag and grabbed it by the nape before turning the back inside out so we could see the mouse (all of this done by headlamp). He then used a small twig to move aside its fur to determine sex and talked about ID points for this species before releasing it back where we had placed the trap. We also marked its belly with a sharpie to make sure we weren't catching the same one when we checked all the traps in the morning. Here are some views of the process:
We ended up going to the camping at the established campground at the north end of Watson Lake, where we ate dinner and studied rodent and carnivore species out of my mammal field guide with our headlamps. Sleep was hard to come by that night since the campground was just above Hwy 89, which was surprisingly busy late at night.
I woke up at 5:00am when I heard my professor and a few others getting up to go check some traps they had set just up the highway at a higher elevation chaparral site. They left before I could make it out of the tent, so I took my time eating breakfast and packing up my tent, all the while listening to the morning chorus of birds (started off by American Robins and Spotted Towhees). After everyone was up and the small group came back from checking the upland traps (all they had were three brush mice, Peromyscus boylii), we went down to Watson Woods to check all of our trap lines. We ended up having a high capture rate throughout the morning, with probably 60-70% of our traps having something in them! We caught four species total in the traps: 33 deer mouse, 3 western harvest mouse (Reithrodontomys megalotis), 5 white-throated woodrat (Neotoma albigula), and 1 Mexican vole (Microtus mexicanus). Here are some of them:
Deer mouse (the last photo is of a deer mouse missing part of its tail):
Western harvest mouse (below). Since it is a less common species there, the biologists there put an ear tag on one of them (shown below). This species basically looks like a tiny version of a deer mouse (same bicoloration of body and tail, and relative body-tail length ratio). One key difference though is that the harvest mouse has a groove on the upper incisors though, which our professor checked for when he was handling it:
White-throated woodrat (below). Most of the ones we caught were females in breeding condition, with swollen nipples. Many of them also were very feisty and defecated/urinated in the bag before our professor got a hold of their nape. These guys are also known as "packrats" and form large stick middens. The middens have been studied in the past because generations of these rodents will use them and plant parts and pollen will get trapped in the middens (and the packrat poop piles) over time. Biologists have found prehistoric pollen and other plant matter in old middens that have enabled them to determine what vegetation was present at that time. From some of these studies in the Sonoran Desert, it has been shown that the lowest deserts used to be covered with pinyon-juniper woodlands and the higher elevation mixed conifer forests used to be more expansive during that different climate. As climate changed during the ebb and flow of glaciation periods in North America, vegetation communities shifted upwards in elevation and various organisms became isolated on different mountain ranges, leading to further speciation. Here are some woodrats:
This woodrat has a botfly infection on its neck. Botflies will lay their eggs directly on a host mammal or another insect/arthropod that will eventually come in contact with a host mammal. The hatched larvae can detect thermal levels of a nearby mammal and burrow into its skin. They will then mature under the skin drawing nutrients from the host mammal, and drop out of the swollen lump they create in the mammal's flesh. It does not kill the host mammal, but something tells me it hurts pretty bad:
Mexican vole (below). This species has only been recently found here and it suggests that riparian restoration occurring at this preserve might be having the intended effect since voles can be an "indicator species". Most voles in the state occur in higher elevation meadow habitats. Voles can be differentiated from mice by the shorter tail, smaller-looking ears (the ears are concealed under the outer fur, so look smaller), and more uniform coloration. They are in a different subfamily (Subfamily Microtinae) than the one containing New World mice and rats (Subfamily Cricetinae). Here is the one we caught in a trap along a grassy meadow along the stream at the preserve:
During the trip, the only other sightings or sign of animals were some rock squirrels, bobcat and raccoon tracks, and some pronghorn along Hwy. 89 in Chino Valley. In between checking the mammal traps we also had to check the mist nets we set up for birds. In these nets we only caught three species: 11 Yellow-rumped Warblers, 7 Lesser Goldfinches, and 1 Anna's Hummingbird. We did not have banding equipment, so all we did was examine their bodies, take photos, and let them go. Here are some views of the birds we captured:
Later in the morning we checked some board "traps" for reptiles with the herpetologists. We mostly found plateau lizards (Sceloporus tristichus), but we also found a few more deer mice making nests under the boards. Here are a few of the lizards:
A few of the ornithology students captured a terrestrial gartersnake (Thamnophis elegans) too while checking the mist nets:
After checking all the traps and loading them back up in the trucks, we listened to the preserve manager talk about the history of the area. Apparently Granite Creek, which runs through the preserve, used to be mined for gravel for a long time and public dumping occurred in it. This with other human activities changed the hydrology of the place and the vegetation. The City of Prescott acquired the land eventually and have been trying to restore hydrological function and riparian vegetation to the ecosystem. There are already lots of young cottonwoods and willows coming in, along with the remnant large cottonwoods. The preserve also has a series of public trails with interpretive signs that lead up to trails along Watson Lake on the north edge of the preserve. The preserve is about to be designated an Important Bird Area (IBA) by the Audubon Society soon. While the manager talked to us, we briefly saw a Common Black-Hawk go by. Here are some views of the Watson Woods:
Around noon we went back to the campground to eat lunch and pack up the rest of our equipment before everyone made their way back to Flagstaff. I stayed a little longer to check the lake for birds with the ornithology students, which was difficult as the winds were gusting to ~30 mph at that time. While walking down to the lake we happened upon a dead Ruddy Duck on the slopes above the lake:
Altogether I observed 46 bird species during our time at Watson Woods and Watson Lake. Besides those already mentioned, highlights included returning Yellow and Lucy's Warblers, Broad-tailed and Black-chinned Hummingbirds, lots of Northern Rough-winged Swallows, one Cassin's Vireo, a flyover Wilson's Snipe, and several Double-crested Cormorants.
After everyone headed back, I went over to the nearby Willow Creek Reservoir to briefly check out the birds in the increasing winds. The main highlight was seeing the breeding colony of Double-crested Cormorants near the trail along the lake. Most of the cormorants were actively carrying sticks to make or reinforce nests, while a few females were already sitting on the nests. Besides the main nesting tree near the trail, I could also see several cormorants setting up nests next to a Great Blue Heron rookery in the grove at the western edge of the lake. Here are views of the cormorant colony:
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