Restoring Aspen Riparian Stands With Beaver on the Northern Yellowstone Winter Range

Aspen (Populus tremuloides) on the Gardiner Ranger District, Gallatin National Forest, have declined over the last half-century. In an attempt to reverse this trend, beaver (Castor canadensis) were reintroduced in Eagle Creek in 1991. In 2005, we assessed the long-term effects of beaver on aspen stands and the associated riparian area in the Eagle Creek drainage. Aspen recovery was estimated by comparing vegetative changes among control sites with \u3c10 percent beaver use\u3e(n = 5), active beaver sites (n = 6), sites abandoned for 1 to 3 years (n = 7), sites abandoned for 4 to 6 years (n = 4), and sites abandoned for 7 to 11 years (n = 5). Aspen stem densities in active sites and sites abandoned by beaver for 1 to 3 years were similar (2.6/m2) and greater (P = 0.01) than the remaining sites. Sprout and sapling densities were greater (P = 0.01) on active and sites abandoned for 1 to 3 years compared to the other sites. Aspen suckers were not able to grow taller than 2m on sites without beaver activity for 4 to 1 years, which prevented aspen recovery. Beaver activity stimulated the growth of aspen sprouts and saplings, but ungulate herbivory prevented successful aspen recovery in Eagle Creek

Grizzly Bears and Humans at Alpine Moth Sites in Wyoming, USA

Army cutworm moths (Euxoa auxiliaris; moths) are an important seasonal higher elevational food source for grizzly bears (Ursus arctos horribilis; bears) in the Greater Yellowstone Ecosystem (Wyoming, Montana, and Idaho, USA). Increased human interaction with bears at moth sites is an important management issue because of the potential for displacing bears and the concern for human safety. Managers will need better information regarding human–bear interactions at high-density moth sites that are also accessible to humans to mitigate potential conflicts. In the summers of 2017 and 2018, we studied human–bear interactions at 2 of the most human accessible moth sites in the Shoshone National Forest, Wyoming. We completed 293 bear surveys and documented 266 bear observations. We also recorded human-use levels at the 2 study sites (north site: 3 groups/year; south site: 35 groups/year). We documented 43 interactions (at the south site only) and obtained location data for 29 interactions. During human–bear interactions, bears strongly avoided humans 80% of the time and had no apparent reaction 20% of the time. Our results indicated that human safety and bear displacement are valid management concerns at the south site. Human safety concerns were most apparent in mountain climbing groups with small group sizes (people, n = 64/70) that were unprepared for encounters with bears. Management concerns for human safety and bear displacement are much lower at the north site. We recommend placing information kiosks at trailheads to inform hikers of dangers associated with grizzly bear concentrations on moth sites

Serologic Survey of Snowshoe Hares (\u3ci\u3eLepus americanus\u3c/i\u3e) in the Greater Yellowstone Area for Brucellosis, Tularemia, and Snowshoe Hare Virus

We examined sera from snowshoe hares (Lepus americanus) livetrapped in the northern Greater Yellowstone Area (GYA), US, for antibodies to Brucella abortus, Francisella tularensis, and snowshoe hare virus (SSHV). Zero of 90, 0 of 67, and 40 of 100 samples were antibody positive for B. abortus, F. tularensis, and SSHV, respectively. Hares were trapped from 2009 to 2012, and of the six animals that were captured twice with at least 1 yr between captures, four developed antibody to SSHV, indicating active exposure to the agent, These findings suggest snowshoe hares in the GYA do not play a significant role as a reservoir of B. abortus, but do maintain the zoonotic, encephalitic SSHV in the population

Specialized visual learning of facial signals of quality in the paper wasp, Polistes dominula

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109618/1/bij12394.pd

GNU Radio

GNU Radio is a free & open-source software development toolkit that provides signal processing blocks to implement software radios. It can be used with readily-available, low-cost external RF hardware to create software-defined radios, or without hardware in a simulation-like environment. It is widely used in hobbyist, academic, and commercial environments to support both wireless communications research and real-world radio systems