Architectural Considerations for Single Operator Management of Multiple Unmanned Aerial Vehicles

Recently, small Unmanned Aircraft Systems (UAS) have become ubiquitous in military battlefield operations due to their intelligence collection capabilities. However, these unmanned systems consistently demonstrate limitations and shortfalls with respect to size, weight, range, line of sight and information management. The United States Air Force Unmanned Aircraft Systems Flight Plan 2009-2047 describes an action plan for improved UAS employment which calls out single operator, multi-vehicle mission configurations. This thesis analyzes the information architecture using future concepts of operations, such as biologically-inspired flocking mechanisms. The analysis and empirical results present insight into the engineering of single-operator multiple-vehicle architectures

Refining self-propelled particle models for collective behaviour

Swarming, schooling, flocking and herding are all names given to the wide variety of collective behaviours exhibited by groups of animals, bacteria and even individual cells. More generally, the term swarming describes the behaviour of an aggregate of agents (not necessarily biological) of similar size and shape which exhibit some emergent property such as directed migration or group cohesion. In this paper we review various individual-based models of collective behaviour and discuss their merits and drawbacks. We further analyse some one-dimensional models in the context of locust swarming. In specific models, in both one and two dimensions, we demonstrate how varying the parameters relating to how much attention individuals pay to their neighbours can dramatically change the behaviour of the group. We also introduce leader individuals to these models with the ability to guide the swarm to a greater or lesser degree as we vary the parameters of the model. We consider evolutionary scenarios for models with leaders in which individuals are allowed to evolve the degree of influence neighbouring individuals have on their subsequent motion

Mixed-species Flock Members’ Reactions to Novel and Predator Stimuli

Novel stimuli are ubiquitous. Few studies have examined mixed-species group reactions to novelty, although the complex social relationships that exist can affect species’ behavior. Additionally, studies rarely consider possible changes in communication. However, for social species, changes in communication, including rates, latencies, or note-types within a call, could potentially be correlated with behavioral traits. As such, this research aimed to address whether vocal behavior is correlated with mixed-species’ reactions to novel objects. I first tested the effect of various novel stimuli on the foraging and calling behavior of Carolina chickadees, Poecile carolinensis, and tufted titmice, Baeolophus bicolor. Chickadees and titmice both had longer latencies to forage in the presence of novel stimuli. Chickadees also modified their vocal behavior, having shorter latencies to call and using more ‘D’ notes in their calls in the presence of novel stimuli compared to titmice. Chickadees and titmice reacted to the novel stimuli similarly to how I would expect them to react to a predator. Therefore, a second experiment was conducted directly comparing chickadee and titmouse reactions to a novel (Mega Bloks®) stimulus and a predator (Cooper’s hawk) stimulus. Chickadees and titmice had an intermediate latency to forage in the presence of a novel stimulus compared to control and predator contexts. Again, chickadees had shorter calling latencies across contexts compared to titmice. As a final experiment, using semi-naturalistic aviaries, I tested whether chickadee flock size and the presence or absence of titmice influenced reactions to novel and predator stimuli. Chickadees called more in smaller chickadee flocks compared to larger chickadee flocks, and also when titmice were absent compared to when they were present. These results were stronger in predator contexts compared to novel contexts. This suggests that conspecific flock size influences calling behavior, such that smaller flocks, which may experience higher stress levels and may be required to exhibit more anti-predatory behavior, call more than larger flocks. Taken together, this work has important implications for the complexity of social relationships in mixed-species groups, the social roles species play within the group, and how group size influences vocal behavior and reactions to various degrees of threat

Seasonal grouping dynamics in a territorial vulture: ecological drivers and social consequences

Despite widespread occurrence of seasonal sociality among animals, little is still known about the social drivers and populationlevel social implications of seasonal grouping behaviours, especially in birds. Here, we studied the combined effects of ecological and social factors on seasonal grouping patterns in a sedentary population of Egyptian vultures living on the Eastern Canary Islands. We focussed on the social significance of large-scale gatherings taking place outside the breeding season at a highly preferred feeding station and a nearby temporary roost. Group sizes at this feeding patch followed a strong seasonal pattern characterized by distinct monthly changes in group composition, according to sex, age and territorial status. In between reproductive periods, vulture numbers at the feeding station may reach up 50% of the total population on a single day. GPS-tracking showed that this increase in vulture numbers was in part due to a shift in foraging range towards the centre of Fuerteventura by low-ranked territorial birds breeding in remote areas. During this period, vultures may spend on average 30% of their monthly time in a social gatherings context, depending on social status. We show that seasonal grouping patterns are shaped by the complex interplay between ecological factors (reproductive constraints, resource seasonality, food predictability), age-specific traits and social competitive processes, while social attraction may be an important additional component. We propose that for facultative social foragers living in highly despotic territorial systems, collective foraging may be of particular relevance regarding the development of hierarchical social relations and maintenance of population-level social cohesionTvO received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. “SocForVul 659008During writing, LG was supported by a Marie Sklodowska-Curie Fellowship of the European Commission (grant number: 747729 “EcoEvoClim”)MG-A was supported by a contract from “Programa de FPU del Ministerio de Educación, Cultura y Deporte” (FPU13/05429)The long-term monitoring of the vulture population has been funded by the projects REN 2000–1556 GLO, CGL2004-00270/BOS, CGL2009-12753-C02-02, CGL2012-40013-C02-01 and CGL2015-66966-C2-1-2-R (Spanish Ministry of Economy and Competitiveness and EU/FEDER)Further support was provided by the Cabildo Insular de Fuerteventura and the Dirección General de Protección de la Naturaleza (Viceconsejería de Medio Ambiente, Canarian Government)

Effects of Traffic Noise on the Social Behavior of Tufted Titmice (Baeolophus bicolor).

The presence of traffic noise and its potential effects on wildlife is a burgeoning topic of research within the fields of conservation behavior, animal behavior, ecology and wildlife management. Accumulated data from these efforts, mostly correlative and rarely-experimental, suggest that traffic noise induces a myriad of species-specific changes to population dynamics, breeding behavior and acoustic structure of avian song. However, the degree of generalizability of these findings is confounded by the limited variety of behaviors studied within a relatively small sample of species. This original research provides experimental evidence of the effects of simulated and real traffic noise on previously unstudied social and vocal behavior in tufted titmice (Baeolophus bicolor). First, titmice were exposed to simulated traffic noise for 8 hours per day to determine whether traffic noise caused changes in social and vocal behavior as had been suggested by previous research. This stimulus, background noise mimicking the duration of exposure, amplitude and frequency parameters of traffic noise, significantly affected several aspects of social behavior. Analyses on the vocal behavior of these subjects suggests that noise only affects call use of the most vocally-productive bird, who also happens to be the most dominant group member. A second study broadcasted recordings of traffic noise to titmice for 2.5 hours per day to test for the effects of the temporary rise in background noise levels resulting from \u27rush hour\u27 on the same social behavior found to be effected in study one. Results of Study 2 corroborated those of Study 1 and indicated that characteristics of traffic noise itself influence its effects. Among the first of its kind, this research demonstrates a direct link between traffic noise and survival-relevant social and vocal behavior

Reactions of Sandhill Cranes Approaching a Marked Transmission Power Line

Sandhill cranes Antigone canadensis, formerly Grus canadensis, are of widespread management focus, particularly where collisions with power lines are an important cause of mortality. Collision mitigation focuses on marking power lines to increase visibility, but collisions persist, perhaps because power line markers are not sufficiently visible in all conditions. Our objective was to compare reaction distances and reaction behaviors during daylight when power lines are presumably more visible, and during darkness when power lines are less visible. The power line we studied was fitted with glow-in-the-dark power line markers intended to increase nocturnal visibility. We found that during daylight, flocks generally avoided the power line by climbing gradually and passed above without making sudden evasive maneuvers. During darkness, flocks, particularly small flocks, were almost equally likely to make sudden evasive maneuvers as to climb gradually. Collision monitoring on the power line we studied conducted concurrent to our study indicated that 94% of collisions occurred during darkness, linking the behaviors we observed to actual mortality. Sandhill cranes also reacted at greater distances and with fewer sudden evasive maneuvers to the glow-in-the-darkmarked power line we studied than to nearby power lines without glowing markers evaluated in a prior study, suggesting that either glowing markers, smaller gaps between markers, or both, improved sandhill cranes’ ability to perceive and react to the power line we studied. By correlating behavioral observations with mortality, our study indicates that proactive low-intensity behavioral observations might be useful surrogates to reactive high-intensity carcass searches in identifying high-risk spans. This approach may also be effective for other species