Detecting Feeding and Estimating the Energetic Costs of Diving in California Sea Lions (Zalophus californianus) Using 3-Axis Accelerometers

Knowledge of when animals feed and the energetic costs of foraging is key to understanding their foraging ecology and energetic trade-offs. Despite this importance, our ability to collect these data in marine mammals remains limited. In this thesis, I address knowledge gaps in both feeding detection and fine-scale diving energetic costs in a model species, the California sea lion (Zalophus californianus). I first developed and tested an analysis method to accurately detect prey capture using 3-axis accelerometers mounted on the head and back of two trained sea lions. An acceleration signal pattern isolated from a ‘training’ subset of synced video and acceleration data was used to build a feeding detector. In blind trials on the remaining data, this detector accurately parsed true feeding from other motions (91-100% true positive rate, 0-4.8% false positive rate), improving upon similar published methods. In a second study, I used depth and acceleration data to estimate the changing body density of 8 wild sea lions throughout dives, and used those data to calculate each sea lion’s energetic expenditure during descent and ascent at fine temporal scales. Energy expenditure patterns closely followed the influence of buoyancy changes with depth. Importantly, sea lions used more energy per second but less energy per meter as dive depth increased, revealing high costs of deep diving. Combined, these studies further our understanding of California sea lion foraging ecology and provide new methods to aid similar future studies

INFLUENCE OF TASTE AND COLOR CUES ON BATHING BY STARLINGS IN APPETITIVE AND ADVERSIVE CONTEXTS: IMPLICATIONS FOR ANIMAL DAMAGE CONTROL

The importance of color and taste in feeding and drinking by omnivorous birds is context·dependent and influenced by learning. Here, we report three experiments designed to assess the influence of such characteristics on starlings. In Experiment 1, eight starlings were given a choice between bathing in red or plain water and 0.15 M NaCI solution or plain water. The frequencies of bathing, drinking, and preening were recorded. Red water was avoided (p \u3c 0.05), but no preferences were observed between NaCI solution and plain water (p \u3e 0.25). That 0.15 M NaCI was not avoided is surprising, because it is rejected by starlings when drinking. Perhaps starlings do not taste substances while bathing but continue to ingest substances that they would otherwise reject. In Experiment 2, we assessed these alternative explanations and also tested (a) whether starlings would bathe in colored water if plain water was unavailable, (b) whether starlings would show preferences among such colors, and (c) whether preferences courd be altered by learning. Twenty-four starlings were assigned to three conditions. Birds in the first condition were presented with red and blue baths and relative preferences for bathing in these colors were assessed. Birds in the second condition were presented with a blue bath and intubated with methiocarb or propylene glycol. Birds in the third condition were presented with a saccharin bath and intubated with methiocarb or propylene glycol. On the four days following treatment, birds in the second condition were given two-choice tests between red and blue baths. Those in the third condition were given two-choice tests between bathing in saccharin solution and plain water. Birds readily bathed in red and blue water when plain water was unavailable. After treatment, however, birds avoided blue water (p \u3c 0.05), but aversions dissipated rapidly. Learned aversions for saccharin were also obtained (p \u3c 0.05); these remained strong over all tests. Experiment 3 was designed to assess the differential importance of taste and color. Sixteen starlings were aSSigned to four groups. Two groups were food-deprived and then given dogfood in a red cup followed by a bath of 0.15 M NaCI or LiCI. The other two groups were presented with a bath of 0.15 M NaCI or LiCI only, as a control. On the four days immediately following treatment, all groups were given two-choice feeding (red vs. blue food cups) and bathing (NaCI vs. plain water) tests. Aversions were expressed towards color in the feeding context (p \u3c 0.05) but not taste in the bathing context (p \u3e 0.25). We inferred that color cues in the feeding context overshadowed taste cues in the bathing context. The present results may have implications for control. Starlings will bathe even under harsh environmental conditions, and one control strategy might be to pair livestock feed with distinctive colors and provide lithium·adulterated bathing stations nearby. Starlings eating feed and bathing in the solution might form color aversions and subsequently avoid the food. Also, the use of such techniques might enhance already existing control, such as the use of starlicide baits. Depredating starlings would be directed toward such baits as birds feeding in the laboratory are directed towards food color combinations not explicitly paired with lithium-induced malaise

Junior Recital, Mason Klein, trumpet

Junior RecitalMason Klein, trumpetRussell Wilson, pianoTuesday, December 3, 2019 at 7pmRecital HallJames W. Black Music Center1015 Grove AvenueRichmond, Va.The presentation of this junior recital will fulfill in part the requirements for the Bachelor of Music Degree in Music Education. Mason Klein studies trumpet with Rex Richardso

Creating Object-Based Stimuli to Explore Media Device Orchestration Reproduction Techniques

Media Device Orchestration (MDO) makes use of interconnected devices to augment a reproduction system, and could be used to deliver more immersive audio experiences to domestic audiences. To investigate optimal rendering on an MDO-based system, stimuli were created via: 1) object-based audio (OBA) mixes undertaken in a reference listening room; and 2) up to 13 rendered versions of these employing a range of installed and ad-hoc loudspeakers with varying cost, quality and position. The programme items include audio-visual material (short film trailer and big band performance) and audio-only material (radio panel show, pop track, football match, and orchestral performance). The object-based programme items and alternate MDO configurations are made available for testing and demonstrating OBA systems

PRELIMINARY EVALUATION OF A GRANULAR TRIMETHACARB FORMULATION FOR DETERRING GRAZING BY AMERICAN COOTS

In a 0.2 ha flight pen, groups of 4 American coots were tested to determine if their grazing activity could be affected by application of a registered granular-trimethacarb insecticide. In the 3 days following treatment (3 kg/ha, a.i.), grazing activity in the treated portions of the 200 m2 experimental plots was reduced an average of 47X. Overall use of the treated areas followed a similar pattern but was less consistent among groups. The addition of methylpyrazine, a strong odorant, produced a strong initial suppression of grazing activity in the treated halves of the plots. However, subsequent rain and a change in the coots\u27 grazing behavior prevented a definitive evaluation of the methylpyrazine treatment. Two birds that died during the trimethacarb-only portion of the study did not have abnormally low levels of brain cholinesterase. However, this finding does not preclude the possibility that they were unable to distinguish treated from untreated grass and consumed lethal amounts of trimethacarb. Additional investigation of methylpyrazine appears warranted; such materials may act to decrease the likelihood that birds will ingest lethal quantities of repellent

Cellular localization and associations of the major lipolytic proteins in human skeletal muscle at rest and during exercise

Lipolysis involves the sequential breakdown of fatty acids from triacylglycerol and is increased during energy stress such as exercise. Adipose triglyceride lipase (ATGL) is a key regulator of skeletal muscle lipolysis and perilipin (PLIN) 5 is postulated to be an important regulator of ATGL action of muscle lipolysis. Hence, we hypothesized that non-genomic regulation such as cellular localization and the interaction of these key proteins modulate muscle lipolysis during exercise. PLIN5, ATGL and CGI-58 were highly (>60%) colocated with Oil Red O (ORO) stained lipid droplets. PLIN5 was significantly colocated with ATGL, mitochondria and CGI-58, indicating a close association between the key lipolytic effectors in resting skeletal muscle. The colocation of the lipolytic proteins, their independent association with ORO and the PLIN5/ORO colocation were not altered after 60 min of moderate intensity exercise. Further experiments in cultured human myocytes showed that PLIN5 colocation with ORO or mitochondria is unaffected by pharmacological activation of lipolytic pathways. Together, these data suggest that the major lipolytic proteins are highly expressed at the lipid droplet and colocate in resting skeletal muscle, that their localization and interactions appear to remain unchanged during prolonged exercise, and, accordingly, that other post-translational mechanisms are likely regulators of skeletal muscle lipolysis

The role of a disulfide bridge in the stability and folding kinetics of Arabidopsis thaliana cytochrome c6A

Cytochrome c 6A is a eukaryotic member of the Class I cytochrome c family possessing a high structural homology with photosynthetic cytochrome c 6 from cyanobacteria, but structurally and functionally distinct through the presence of a disulfide bond and a heme mid-point redox potential of + 71 mV (vs normal hydrogen electrode). The disulfide bond is part of a loop insertion peptide that forms a cap-like structure on top of the core α-helical fold. We have investigated the contribution of the disulfide bond to thermodynamic stability and (un)folding kinetics in cytochrome c 6A from Arabidopsis thaliana by making comparison with a photosynthetic cytochrome c 6 from Phormidium laminosum and through a mutant in which the Cys residues have been replaced with Ser residues (C67/73S). We find that the disulfide bond makes a significant contribution to overall stability in both the ferric and ferrous heme states. Both cytochromes c 6A and c 6 fold rapidly at neutral pH through an on-pathway intermediate. The unfolding rate for the C67/73S variant is significantly increased indicating that the formation of this region occurs late in the folding pathway. We conclude that the disulfide bridge in cytochrome c 6A acts as a conformational restraint in both the folding intermediate and native state of the protein and that it likely serves a structural rather than a previously proposed catalytic role. © 2011 Elsevier B.V. All rights reserved

Bestial boredom: a biological perspective on animal boredom and suggestions for its scientific investigation

Boredom is likely to have adaptive value in motivating exploration and learning, and many animals may possess the basic neurological mechanisms to support it. Chronic inescapable boredom can be extremely aversive, and understimulation can harm neural, cognitive and behavioural flexibility. Wild and domesticated animals are at particular risk in captivity, which is often spatially and temporally monotonous. Yet biological research into boredom has barely begun, despite having important implications for animal welfare, the evolution of motivation and cognition, and for human dysfunction at individual and societal levels. Here I aim to facilitate hypotheses about how monotony affects behaviour and physiology, so that boredom can be objectively studied by ethologists and other scientists. I cover valence (pleasantness) and arousal (wakefulness) qualities of boredom, because both can be measured, and I suggest boredom includes suboptimal arousal and aversion to monotony. Because the suboptimal arousal during boredom is aversive, individuals will resist low arousal. Thus, behavioural indicators of boredom will, seemingly paradoxically, include signs of increasing drowsiness, alongside bouts of restlessness, avoidance and sensation-seeking behaviour. Valence and arousal are not, however, sufficient to fully describe boredom. For example, human boredom is further characterized by a perception that time ‘drags’, and this effect of monotony on time perception can too be behaviourally assayed in animals. Sleep disruption and some abnormal behaviour may also be caused by boredom. Ethological research into this emotional phenomenon will deepen understanding of its causes, development, function and evolution, and will enable evidence-based interventions to mitigate human and animal boredom

HST Grism Observations of a Gravitationally Lensed Redshift 10 Galaxy

We present deep spectroscopic observations of a Lyman-break galaxy candidate (hereafter MACS1149-JD) at $z\sim9.5$ with the $\textit{Hubble}$ Space Telescope ($\textit{HST}$) WFC3/IR grisms. The grism observations were taken at 4 distinct position angles, totaling 34 orbits with the G141 grism, although only 19 of the orbits are relatively uncontaminated along the trace of MACS1149-JD. We fit a 3-parameter ($z$, F160W mag, and Ly$\alpha$ equivalent width) Lyman-break galaxy template to the three least contaminated grism position angles using an MCMC approach. The grism data alone are best fit with a redshift of $z_{\mathrm{grism}}=9.53^{+0.39}_{-0.60}$ ($68\%$ confidence), in good agreement with our photometric estimate of $z_{\mathrm{phot}}=9.51^{+0.06}_{-0.12}$ ($68\%$ confidence). Our analysis rules out Lyman-alpha emission from MACS1149-JD above a $3\sigma$ equivalent width of 21 \AA{}, consistent with a highly neutral IGM. We explore a scenario where the red $\textit{Spitzer}$/IRAC $[3.6] - [4.5]$ color of the galaxy previously pointed out in the literature is due to strong rest-frame optical emission lines from a very young stellar population rather than a 4000 \AA{} break. We find that while this can provide an explanation for the observed IRAC color, it requires a lower redshift ($z\lesssim9.1$), which is less preferred by the $\textit{HST}$ imaging data. The grism data are consistent with both scenarios, indicating that the red IRAC color can still be explained by a 4000 \AA{} break, characteristic of a relatively evolved stellar population. In this interpretation, the photometry indicate that a $340^{+29}_{-35}$ Myr stellar population is already present in this galaxy only $\sim500~\mathrm{Myr}$ after the Big Bang.Comment: Accepted to ApJ. This is the accepted versio