Occupancy

About: Occupancy is a research topic. Over the lifetime, 2757 publications have been published within this topic receiving 68288 citations.

BOES: Building Occupancy Estimation System using sparse ambient vibration monitoring

Abstract: In this paper, we present a room-level building occupancy estimation system (BOES) utilizing low-resolution vibration sensors that are sparsely distributed. Many ubiquitous computing and building maintenance systems require fine-grained occupancy knowledge to enable occupant centric services and optimize space and energy utilization. The sensing infrastructure support for current occupancy estimation systems often requires multiple intrusive sensors per room, resulting in systems that are both costly to deploy and difficult to maintain. To address these shortcomings, we developed BOES. BOES utilizes sparse vibration sensors to track occupancy levels and activities. Our system has three major components. 1) It extracts features that distinguish occupant activities from noise prone ambient vibrations and detects human footsteps. 2) Using a sequence of footsteps, the system localizes and tracks individuals by observing changes in the sequences. It uses this tracking information to identify when an occupant leaves or enters a room. 3) The entering and leaving room information are combined with detected individual location information to update the room-level occupancy state of the building. Through validation experiments in two different buildings, our system was able to achieve 99.55% accuracy for event detection, less than three feet average error for localization, and 85% accuracy in occupancy counting.

Assessing global patterns in mammalian carnivore occupancy and richness by integrating local camera trap surveys

Abstract: Aim Biodiversity loss is a major driver of ecosystem change, yet the ecological data required to detect and mitigate losses are often lacking. Recently, camera trap surveys have been suggested as a method for sampling local wildlife communities, because these observations can be collated into a global monitoring network. To demonstrate the potential of camera traps for global monitoring, we assembled data from multiple local camera trap surveys to evaluate the interchange between fine- and broad-scale processes impacting mammalian carnivore communities. Location Argentina, Belize, Botswana, Canada, Indonesia, Iran, Madagascar, Nepal, Norway, Senegal, South Africa, and the U.S.A. Methods We gathered camera trap data, totalling > 100,000 trap nights, from across five continents. To analyse local and species-specific responses to anthropogenic and environmental variables, we fitted multispecies occurrence models to each study area. To analyse global-level responses, we then fitted a multispecies, multi-area occurrence model. Results We recorded 4,805 detections of 96 mammalian carnivore species photographed across 1,714 camera stations located in 12 countries. At the global level, our models revealed that carnivore richness and occupancy within study areas was positively associated with prey availability. Occupancy within study areas also tended to increase with greater protection and greater distances to roads. The strength of these relationships, however, differed among countries. Main conclusions We developed a research framework for leveraging global camera trap data to evaluate patterns of mammalian carnivore occurrence and richness across multiple spatial scales. Our research highlights the importance of intact prey populations and protected areas in conserving carnivore communities. Our research also highlights the potential of camera traps for monitoring wildlife communities and provides a case study for how this can be achieved on a global scale. We encourage greater integration and standardization among camera trap studies worldwide, which would help inform effective conservation planning for wildlife populations both locally and globally.

Habitat patch occupancy by toads (bufo punctatus) in a naturally fragmented desert landscape

Abstract: Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo punctatus )i n the southwestern United States and Mexico commonly inhabits wetlands that have become much smaller and fewer since the late Pleistocene. This study tests two predictions based on metapopulation theory, that the incidence of habitat patch occupancy is directly related to patch size and that it is inversely related to patch isolation, and a third, potentially competing hypothesis, that patch occupancy is influenced by local environmental conditions. In a 20 000 km 2 area of the eastern Mojave Desert, 128 potential habitat patches (primarily springs) were identified and surveyed for local environmental characteristics and presence/ absence of B. punctatus. Patch size metrics reflected extent of water and riparian vegetation of several types. Patch isolation metrics were based on nearest-neighbor distances, cal- culated both as Euclidian distance and distance via connecting drainage channels. B. punc- tatus was found at 73% of the sites, including all of the 16 historic (pre-1970) sites. Patches were generally quite small, with water extending a median distance of only 200 m and median area of 72 m 2 . Median nearest-neighbor distances among patches were 1.8 km Euclidian distance (range: 0.4-22.0 km) and 6.8 km via drainage channels (range: 0.5- 64.9 km). Based on stepwise multiple logistic regression, the incidence of patch occupancy increased significantly with patch size and was also significantly related to elevation, lat- itude, and four metrics that were associated with rocky terrain, periodic scouring water flows, and ephemeral water. In contrast, incidence of patch occupancy was not significantly related to patch isolation. These findings are consistent with a ''patchy population'' model, rather than the classical equilibrium metapopulation model, implying frequent dispersal among patches and virtually no local extinctions. We speculate that B. punctatus in the Mojave Desert today occurs primarily in a patchy population or populations within mountain ranges that are isolated from patchy populations in other ranges. The influence of local environmental characteristics on patch occupancy demonstrates the importance of including patch quality metrics in tests of predictions for patch occupancy based on metapopulation theory.