Recreational use in dispersed public lands measured using social media data and on-site counts.

Outdoor recreation is one of many important benefits provided by public lands. Data on recreational use are critical for informing management of recreation resources, however, managers often lack actionable information on visitor use for large protected areas that lack controlled access points. The purpose of this study is to explore the potential for social media data (e.g., geotagged images shared on Flickr and trip reports shared on a hiking forum) to provide land managers with useful measures of recreational use to dispersed areas, and to provide lessons learned from comparing several more traditional counting methods. First, we measure daily and monthly visitation rates to individual trails within the Mount Baker-Snoqualmie National Forest (MBSNF) in western Washington. At 15 trailheads, we compare counts of hikers from infrared sensors, timelapse cameras, and manual on-site counts, to counts based on the number of shared geotagged images and trip reports from those locations. Second, we measure visitation rates to each National Forest System (NFS) unit across the US and compare annual measurements derived from the number of geotagged images to estimates from the US Forest Service National Visitor Use Monitoring Program. At both the NFS unit and the individual-trail scales, we found strong correlations between traditional measures of recreational use and measures based on user-generated content shared on the internet. For national forests in every region of the country, correlations between official Forest Service statistics and geotagged images ranged between 55% and 95%. For individual trails within the MBSNF, monthly visitor counts from on-site measurements were strongly correlated with counts from geotagged images (79%) and trip reports (91%). The convenient, cost-efficient and timely nature of collecting and analyzing user-generated data could allow land managers to monitor use over different seasons of the year and at sites and scales never previously monitored, contributing to a more comprehensive understanding of recreational use patterns and values.

Prior sexual experience increases hippocampal cell proliferation and decreases risk assessment behavior in response to acute predator odor stress in the male rat.

Acute exposure to the predator odor trimethylthiazoline (TMT) induces defensive behavior in the male rat, and this response is associated with a decrease in cell proliferation within the dentate gyrus of the hippocampus. Sexual experience appears to be protective, as it exerts anxiolytic-like effects and sustains gonadal function in the face of stress. To examine the influence of sexual experience on subsequent stress-induced defensive behavior and cell proliferation in the hippocampus we exposed adult male rats to TMT odor with or without prior exposure to sexually receptive female rats. A subset of rats was injected with the DNA-synthesis marker bromodeoxyuridine (BrdU; 200 mg/kg) during TMT exposure and perfused 24 h later to provide an index of cell proliferation within the dentate gyrus. In response to TMT, sexual experience reduced the duration of stretched attend postures, but had no significant effect on defensive burying. Furthermore, TMT induced a significant increase in cell proliferation in the dentate gyrus, but only in males with sexual experience. The results demonstrate an influence of socio-sexual experience on the magnitude of the behavioral and neural responses to predator odor stress.

Castration differentially affects spatial working and reference memory in male rats.

A male advantage for spatial learning and memory tasks is well documented among humans and rodents. A possible physiological cause for this male advantage is activational effects of androgens among males. The spatial memory of eight castrated and eight sham-castrated adult male rats was compared using a working-reference memory version of the eight-arm radial arm maze followed by a reference memory version of the Morris water maze. After maze testing, blood was collected from each rat, and testosterone levels were determined using radioimmunoassay. In the radial arm maze, castrates committed significantly more working memory errors and significantly fewer reference memory errors than did shams. In the water maze, no statistically significant differences were found for acquisition or retention. There was a trend for shams with higher testosterone levels to have better retention in the water maze, but this seemed to be due to higher levels of perseverance rather than better reference memory. Castration may have affected performance in the radial arm maze and not in the water maze because the radial arm maze was a more difficult task or because the water maze was aversively motivated while the radial arm maze was appetitively motivated. Our results indicate that androgens improve working memory and may impair reference memory, but the effects of androgens on reference memory seem to be task dependent.