Gray Seal Behavior in a Fish Weir Observed Using Dual-Frequency Identification Sonar

2014 ◽  
Vol 48 (4) ◽  
pp. 72-78 ◽  
Author(s):  
Owen C. Nichols ◽  
Ernie Eldredge ◽  
Steven X. Cadrin
Keyword(s):  
Halichoerus Grypus ◽  
Fishing Gear ◽  
Dual Frequency ◽  
Pomatomus Saltatrix ◽  
Negative Effects ◽  
Behavioral Observations ◽  
Frequency Identification ◽  
And Behavior ◽  
Fish Weir ◽  
Gray Seals

AbstractMarine mammal depredation can have significant negative effects on the performance of fixed fishing gears. Gray seals (Halichoerus grypus grypus) have been observed feeding on fish weir catches in Nantucket Sound, and remnants of longfin inshore squid (Doryteuthis pealeii) and finfish in the nets are attributable to seal depredation. A dual-frequency identification sonar (DIDSON) deployed in a weir to monitor squid and fish occurrence captured observations of seal presence and behavior. Continuous recordings of 24+ h were subsampled at multiple intervals to optimize the likelihood of seal detection while minimizing processing time. Targets detected and identified to species included squid, bluefish (Pomatomus saltatrix), and gray seals. Seal occurrence in the weir was observed primarily at night. The presence and behavior of seals may negatively affect the efficiency of the weir due to disruption of the passage of schooling squid and finfish into the catch chamber. Behavioral observations collected using DIDSON can aid in the design of fishing gear modifications to reduce seal depredation.

scholarly journals Daily and seasonal movements of Cape Cod gray seals vary with predation risk

2020 ◽  
Vol 644 ◽  
pp. 215-228 ◽  
Author(s):  
JH Moxley ◽  
G Skomal ◽  
J Chisholm ◽  
P Halpin ◽  
DW Johnston
Keyword(s):  
Predation Risk ◽  
White Shark ◽  
Halichoerus Grypus ◽  
Cape Cod ◽  
Gray Seal ◽  
Predator Prey ◽  
Seasonal Movements ◽  
Nocturnal Foraging ◽  
And Behavior ◽  
Gray Seals

White sharks Carcharodon carcharias and gray seals Halichoerus grypus are re-establishing their ecological roles within the Northwestern Atlantic Ocean, presenting an opportunity to understand gray seal movement and at-sea behavior under predation risk. As with other shark-seal hotspots, movements to and from terrestrial haul outs can be risky for gray seals, thereby eliciting antipredator strategies. We investigated the movement and coastal behavior of gray seals on Cape Cod (USA) in relation to seasonal and diel changes in white shark activity. Analyzing 412 trips to sea by 8 seals and more than 25000 acoustic detections from 23 individual white sharks, we observed seasonally homogeneous movements in seal behavior during months with greater shark presence. During riskier months, seal behavior manifested in near-exclusive nocturnal foraging, reduced offshore ranging, and limited at-sea activity. On these nocturnal trips to sea, seals returning to haul outs tended to avoid daybreak and traversed during diel minima in shark activity. However, seals tended to depart haul outs at dusk when shark presence was maximal. As conservation efforts succeed in rebuilding depleted populations of coastal predators, studying re-emerging predator-prey interactions can enhance our understanding about the drivers of movement and behavior.

If I Had Something to Add, I Would

2020 ◽  
Vol 19 (2) ◽  
pp. 86-96
Author(s):  
Isaac A. Lindquist ◽  
Emily E. Adams ◽  
Joseph A. Allen
Keyword(s):  
Job Attitudes ◽  
Negative Effects ◽  
Meeting Effectiveness ◽  
And Behavior ◽  
Attitudes And Behavior

Abstract. Most employees participate in workplace meetings, and their experiences in meetings can vary greatly, which can lead to positive or negative effects on both job attitudes and behavior. In this study, we examined the effect that a meeting attendee’s competence in the meeting topic had on their participation in the meeting and their perception of meeting effectiveness. Results indicated those with higher levels of competence in the meeting topic were more likely to participate and through participation found their meeting more effective; this relationship was stronger when employee dissent in the meetings was high. Leaders should ensure that those who are present in a meeting are competent in the topic of the meeting and encourage them to participate.

The influence of media on upbringing and behavior of children

GIS Business ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. 656-666
Author(s):  
Dr. Entisar Al-Obaidi
Keyword(s):  
New Technologies ◽  
The Internet ◽  
Negative Effects ◽  
Online Newspapers ◽  
Media Messages ◽  
Other Information ◽  
Family Home ◽  
Effects Of Media ◽  
And Behavior ◽  
Harmful Effects

Media refers to the channels of communication through which we distribute news, education, movies, music, advertising messages and other information. It includes physical and online newspapers and magazines, television, radio, telephone, the Internet, fax and billboards, are a dominant force in lives of children. Although television is remaining the predominant medium for children and adolescents, the new technologies are become more popular. We have to concern about the potential harmful effects of media "messages and images"; however, the positive and negative effects of media should be recognized. Parents have to establish the plan for all media in family home. Media that are influences on children should be recognized by "schools, policymakers, product advertisers, and entertainment producers".

scholarly journals Dynamics of the formation of a differentiation track conditioned reflex to sound stimuli of a certain duration in the gray seal Halichoerus grypus Fabricius, 1791 by the methods of operant conditioning.

2021 ◽  
Vol 12 (3-2021) ◽  
pp. 7-13
Author(s):  
A.F. Berdnik ◽  
Keyword(s):  
Reaction Time ◽  
Operant Conditioning ◽  
Conditioned Reflex ◽  
Audio Signal ◽  
Halichoerus Grypus ◽  
Audio Signals ◽  
Gray Seal ◽  
And Behavior ◽  
Sound Duration

In the course of the study, a 15-year-old female gray seal was trained to press a button after displaying an audio signal for 5 seconds and ignore similar audio signals of longer or shorter duration. The conducted research has demonstrated the ability of the experimental seal to reliably differentiate sound signals with a difference in sound duration of 3 seconds. Changes in the reaction time and behavior of the seal during the demonstration of sound stimuli with distinguishable and indistinguishable time ranges are described.

scholarly journals Acute social isolation alters neurogenomic state in songbird forebrain

2019 ◽  
Vol 117 (38) ◽  
pp. 23311-23316 ◽  
Author(s):  
Julia M. George ◽  
Zachary W. Bell ◽  
Daniel Condliffe ◽  
Kirstin Dohrer ◽  
Teresa Abaurrea ◽  
...  
Keyword(s):  
Gene Expression ◽  
Social Isolation ◽  
Axonal Guidance ◽  
Sequencing Analysis ◽  
Negative Effects ◽  
Auditory Forebrain ◽  
Gene Sets ◽  
Brain And Behavior ◽  
And Behavior ◽  
The Brain

Prolonged social isolation has negative effects on brain and behavior in humans and other social organisms, but neural mechanisms leading to these effects are not understood. Here we tested the hypothesis that even brief periods of social isolation can alter gene expression and DNA methylation in higher cognitive centers of the brain, focusing on the auditory/associative forebrain of the highly social zebra finch. Using RNA sequencing, we first identified genes that individually increase or decrease expression after isolation and observed general repression of gene sets annotated for neurotrophin pathways and axonal guidance functions. We then pursued 4 genes of large effect size: EGR1 and BDNF (decreased by isolation) and FKBP5 and UTS2B (increased). By in situ hybridization, each gene responded in different cell subsets, arguing against a single cellular mechanism. To test whether effects were specific to the social component of the isolation experience, we compared gene expression in birds isolated either alone or with a single familiar partner. Partner inclusion ameliorated the effect of solo isolation on EGR1 and BDNF, but not on FKBP5 and UTS2B nor on circulating corticosterone. By bisulfite sequencing analysis of auditory forebrain DNA, isolation caused changes in methylation of a subset of differentially expressed genes, including BDNF. Thus, social isolation has rapid consequences on gene activity in a higher integrative center of the brain, triggering epigenetic mechanisms that may influence processing of ongoing experience.

Nasal heat and water exchange in gray seals

1987 ◽  
Vol 253 (6) ◽  
pp. R883-R889 ◽  
Author(s):  
L. P. Folkow ◽  
A. S. Blix
Keyword(s):  
Water Exchange ◽  
Ambient Air ◽  
Minute Volume ◽  
Halichoerus Grypus ◽  
Evaporative Water ◽  
Air Temperatures ◽  
Respiratory Heat Loss ◽  
Average Maximum ◽  
Lower Critical Temperature ◽  
Gray Seals

Metabolic rate (MR), expired air temperature (Tex), respiratory frequency (f), respiratory minute volume (V), and skin (Ts) and body (Tb) temperatures were recorded in three gray seals (Halichoerus grypus) at ambient air temperatures (Ta) between -40 and +20 degrees C. At Ta within the thermoneutral zone, MR averaged 3.7 W.kg-0.75, while mean V was 0.26 1.min-1.kg-0.75. At Ta below -11 degrees C [apparent lower critical temperature (Tlc)], both MR and V increased linearly with decreasing Ta. Average maximum MR (9.6 W.kg-0.75) and V (0.57 1.min-1.kg-0.75) were both recorded at Ta of -40 degrees C. Tex decreased with decreasing Ta to an average minimum value of 8 degrees C at Ta of -30 degrees C. The highest Tex recorded was 32 degrees C at Ta of +20 degrees C. At Ta of -20 degrees C, both total respiratory heat loss, with one exception, and respiratory evaporative water loss reached their lowest values. At this Ta, 66% of the heat and 80% of the water added to the inspired air were regained on expiration. We suggest that nasal heat exchange may be of considerable importance for thermal and water balance in many pinnipeds.

Helping That Hurts Intended Beneficiaries: A New Perspective on the Dark Side of Helping Organizational Citizenship Behavior

2017 ◽  
Author(s):  
Anna Lennard ◽  
Linn Van Dyne
Keyword(s):  
Organizational Citizenship ◽  
Organizational Citizenship Behavior ◽  
Performance Outcomes ◽  
Dark Side ◽  
Citizenship Behavior ◽  
Affective States ◽  
Negative Consequences ◽  
Negative Effects ◽  
New Perspective ◽  
And Behavior

Organizational citizenship behavior (OCB) is essential for organizations to gain and maintain competitive advantage in environments with constantly evolving demands. Although most of the literature implicitly assumes that OCB predicts positive work attitudes, affective states, cognitions, and behavior for employees and organizations, some work raises the question of when OCB fails to produce positive consequences, and scholars have called for a more balanced perspective that acknowledges possible negative consequences of OCB. In this chapter, we focus on the unintended negative outcomes of helping OCB to recipients. More specifically, we consider factors that paradoxically cause positively intended helping to backfire and have negative effects on recipients. To date, most research on outcomes of OCB has focused on performance outcomes. In contrast, we focus on nonperformance outcomes for recipients of helping because nonperformance outcomes are more proximal and can shed light on processes that influence more distal outcomes, such as performance.

Seasonal variability and individual consistency in gray seal (Halichoerus grypus) isotopic niches

2019 ◽  
Vol 97 (11) ◽  
pp. 1071-1077
Author(s):  
K.M. Hernandez ◽  
A.L. Bogomolni ◽  
J.H. Moxley ◽  
G.T. Waring ◽  
R.A. DiGiovanni ◽  
...  
Keyword(s):  
United States ◽  
Seasonal Variability ◽  
Foraging Ecology ◽  
Population Level ◽  
The United States ◽  
Halichoerus Grypus ◽  
Dietary Specialization ◽  
Gray Seal ◽  
Individual Consistency ◽  
Gray Seals

Although it is often assumed that individuals in generalist populations are equivalent, recent research indicates that individual dietary specialization can be common in marine predators. Gray seals (Halichoerus grypus (Fabricius, 1791)) were considered locally extinct in United States waters by 1958 but have since recolonized the region. Although considered generalists, less is known about gray seal foraging ecology in the United States. To address this, we used carbon and nitrogen stable isotope analyses to investigate the foraging niches of adult gray seals in Massachusetts, USA. We examined skin, fur, and blood components to investigate seasonal variability and individual consistency in foraging niches, and serially sampled vibrissae to quantify the degree of individual foraging specialization in this population. Our results suggest that seals shift from coastal foraging habitats before molt to offshore habitats after molt, with a coincident shift from higher to lower trophic-level prey. Adult gray seals also exhibited individual consistency in foraging niches independent of population-level shifts and reflect a generalist population composed of individual foraging specialists. These findings serve as a baseline for subsequent research on gray seals in United States waters that could help to determine the mechanisms which promote individual specialization in this population.

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