Assessing the Attractiveness of Three Baits for Roof Rats in California Citrus Orchards

Roof rats (Rattus rattus) are common pests of tree fruit and nut orchards in California. Tracking tunnels are an effective and practical tool for monitoring changes in roof rat numbers in orchard systems, but they rely on the use of attractive baits to draw in rats to the tracking surface. The identification of baits that are both attractive and readily available would be of great assistance for monitoring changes in roof rat numbers within agricultural fields. Therefore, we tested the attractiveness of a soft bait (Liphatech Rat and Mouse AttractantTM), a wax block (Liphatech NoToxTM), peanut butter, and a control (i.e., no bait applied) to roof rats when applied within tracking tunnels. We did not observe a difference in visitation to any of the tested attractants, although all attractants yielded greater visitation rates than control tunnels. However, tracking tunnels without any attractant were still visited at a relatively high rate, indicating the tracking tunnel is attractive to roof rats. As such, monitoring tools that provide shelter may increase detectability, although this would need to be verified. Regardless, all three food-based lures we tested increased the attractiveness of tracking tunnels and could be used to increase visitation to these monitoring devices.

TRACKING DINOSAURS IN COARSE-GRAINED SEDIMENTS FROM THE UPPER TRIASSIC OF ARDÈCHE (SOUTHEASTERN FRANCE)

ABSTRACT Coarse-grained sediments deposited in high-energy environments are usually considered unfavorable to the preservation of fossil tracks. Here we report dinosaur footprints showing good physical preservation, despite being found in coarse-grained sandstones of alluvial origin from the Upper Triassic of Ardèche, southeastern France. The ichnoassemblage, dominated by Grallator isp., raises questions about the processes leading to the formation and preservation of tracks in coarse-grained sediments. The track-bearing surface is a medium- to coarse-grained quartz arenite that is microconglomeratic locally. The tracking surface grain size ranges from 0.2 to 2 mm and numerous pebbles are present. It is overlain by a succession of thin, intercalated layers of claystones and siltstones, themselves covered by a mix of siltstones and coarse-grained sandstones. We interpret this succession as a progressive decrease in energy due to channel migration culminating in channel abandonment, and the establishment of a lower energy setting where the tracking surface formed. Sedimentological and taphonomic observations indicate that the trackmakers walked on fine-grained layers (clay, silt) in which true tracks formed. The passage of the animals along the tracking surface deformed the older coarse-grained sand layers and resulted in the formation of the transmitted undertracks. The fine-grained layer helped record the pedal anatomy of the trackmakers and contributed to protecting the transmitted undertracks from destruction. Overall, we suggest that the fossil footprints were preserved by abiotic processes only, the main factor being the lithological contrast between successive sedimentary layers. The exceptional preservation of those relatively high quality undertracks in coarse-grained deposits contrasts sharply with the prevailing models of true track formation involving fine-grained sediments and microbial mats present in low-energy environments. This mode of undertrack formation may have been relatively frequent elsewhere but potentially overlooked in previous studies.

A Multi-Module Fixed Inclinometer for Continuous Monitoring of Landslides: Design, Development, and Laboratory Testing

Continuous monitoring of landslides is of basic importance for understanding their behavior, defining their 3D geometry, and providing a basis for early warning purposes. While a number of instrumentations can be used for tracking surface displacement, only automatic or fixed multi-module inclinometers can be used for continuous monitoring of displacement at depth, providing valuable information for landslide geometry reconstruction. Since these instruments are very expensive, thus rarely used, a low-cost and multi-module fixed inclinometer for continuous landslide monitoring has been developed. In this paper, the electronics of the system, including sensor characteristics and optimization, controlling software, and structure are presented. For system development, a single module prototype was first developed and tested in the field to ensure sufficient measuring performance. Subsequently, the multi-module system was designed, assembled, and tested in controlled conditions. Test results indicate the good performance of the system with a displacement measuring accuracy of 0.37% of the length of the inclinometer chain. The linearity test indicates the high linearity of the measures, especially in the range ±20°, which is the typical operating range of such kinds of instrumentations. The thermal efficiency test indicates the high efficiency of the system in preventing measuring errors caused by thermal drifting.

Extended Target Tracking and Feature Estimation for Optical Sensors Based on the Gaussian Process

A problem of tracking surface shape-shifting extended target by using gray scale pixels on optical image is considered. The measurement with amplitude information (AI) is available to the proposed method. The target is regarded as a convex hemispheric object, and the amplitude distribution of the extended target is represented by a solid radial function. The Gaussian process (GP) is applied and the covariance function of GP is modified to fit the convex hemispheric shape. The points to be estimated on the target surface are selected reasonably in the hemispheric space at the azimuth and pitch directions. Analytical representation of the estimated target extent is provided and the recursive process is implemented by the extended Kalman filter (EKF). In order to demonstrate the algorithm’s ability of tracking complex shaped targets, a trailing target characterized by two feature parameters is simulated and the two feature parameters are extracted with the estimated points. The simulations verify the validity of the proposed method with compared to classical algorithms.

India’s Evolving Maritime Domain Awareness Strategy in the Indian Ocean

Darshana Baruah, an emerging Indian maritime security analyst, examines India’s heightened focus on improving maritime domain awareness in the coastal domain, EEZ and far seas. This is increasingly being driven by growing naval presence in the Indian Ocean. Of particular concern is India’s ability to monitor the passage of PLA Navy submarine passages to Pakistan and elsewhere in the Indian Ocean. Despite improved maritime situational awareness in coastal waters, India still has difficulty in tracking surface and subsurface vessels transiting its EEZ or neighbouring waters. This will likely require coordination and collaboration with friendly states. Baruah concludes that despite India’s traditional attachment to strategic autonomy, the difficulties in any one country developing maritime domain awareness across the Indian Ocean will be a key driver in greater defence cooperation with the United States and its allies.