scholarly journals Negative effects of gardening damselfish Stegastes planifrons on coral health depend on predator abundance

2015 ◽  
Vol 528 ◽  
pp. 289-296 ◽  
Author(s):  
MJA Vermeij ◽  
H DeBey ◽  
G Grimsditch ◽  
J Brown ◽  
D Obura ◽  
...  
Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Denise P. Silva ◽  
Helena D. M. Villela ◽  
Henrique F. Santos ◽  
Gustavo A. S. Duarte ◽  
José Roberto Ribeiro ◽  
...  

Abstract Background Beginning in the last century, coral reefs have suffered the consequences of anthropogenic activities, including oil contamination. Chemical remediation methods, such as dispersants, can cause substantial harm to corals and reduce their resilience to stressors. To evaluate the impacts of oil contamination and find potential alternative solutions to chemical dispersants, we conducted a mesocosm experiment with the fire coral Millepora alcicornis, which is sensitive to environmental changes. We exposed M. alcicornis to a realistic oil-spill scenario in which we applied an innovative multi-domain bioremediator consortium (bacteria, filamentous fungi, and yeast) and a chemical dispersant (Corexit® 9500, one of the most widely used dispersants), to assess the effects on host health and host-associated microbial communities. Results The selected multi-domain microbial consortium helped to mitigate the impacts of the oil, substantially degrading the polycyclic aromatic and n-alkane fractions and maintaining the physiological integrity of the corals. Exposure to Corexit 9500 negatively impacted the host physiology and altered the coral-associated microbial community. After exposure, the abundances of certain bacterial genera such as Rugeria and Roseovarius increased, as previously reported in stressed or diseased corals. We also identified several bioindicators of Corexit 9500 in the microbiome. The impact of Corexit 9500 on the coral health and microbial community was far greater than oil alone, killing corals after only 4 days of exposure in the flow-through system. In the treatments with Corexit 9500, the action of the bioremediator consortium could not be observed directly because of the extreme toxicity of the dispersant to M. alcicornis and its associated microbiome. Conclusions Our results emphasize the importance of investigating the host-associated microbiome in order to detect and mitigate the effects of oil contamination on corals and the potential role of microbial mitigation and bioindicators as conservation tools. Chemical dispersants were far more damaging to corals and their associated microbiome than oil, and should not be used close to coral reefs. This study can aid in decision-making to minimize the negative effects of oil and dispersants on coral reefs.


2016 ◽  
Vol 64 (3) ◽  
Author(s):  
Marco Agustín Liñán-Cabello ◽  
Aramis Olivos-Ortiz ◽  
Sonia Quijano-Scheggia ◽  
Daniela Muñiz Anguiano ◽  
María Luisa Reséndiz-Flores ◽  
...  

Coral reef ecosystems are under stress of different origins, from factors including sedimentation, fragmentation, overfishing, and tourism, depending on their geographical location, depth, and proximity to recreation areas. In this study of Juluapan Lagoon, we examined the relationship between various water-quality attributes and the status indicators of the coral community at La Boquita reef. During 2011 (12 months of sampling), six monitoring stations in the Juluapan lagoon were established in order to observe the gradient of the distribution of the physicochemical parameters: three stations on the upper part, or BI, (S4 to S6) and three more in the lower part, or BII, (S1 to S3). A control station (CS) was located in the coral reef close to the lagoon channel, and where dissolved inorganic nutrients and cellular carbon content were determined. Additionally, we considered the monitoring of three of the eight largest coral structures/headlands of this community: the first was the station closest to the channel communicating with Juluapan lagoon (C1), the second was in the intermediate region with respect to that lagoon (C2), and the third was farthest from the channel (C3). Three line intercept transects (LIT) 30 m in length and perpendicular to the coast provenance were established in each station, and the parameters indicative of the status of corals were evaluated in an area of 60 m2 on each transect (180 m2 by the station). Turbidity, evidence of fishing, signs of settling, algal coverage, abundance of fish, rate of sediment, and coral health records (as for CoralWach chart) were determined in situ and from digital photographs and videos. Considering various community status indicators used in the reef area, we could recognize a state of general deterioration, which was reflected in the loss of 17 % of coral coverage. The main anthropogenic disturbances in adjacent areas to La Boquita reef included wastewater discharges into the lagoon, tourist developments in the coastal zone, deforestation and erosion resulting from inappropriate development, and the runoff of nutrients from agricultural lands nearby the lagoon. All these significantly contributed to the nutrient-enriched waters of the lagoon, especially in summer, with negative effects on the coral community. Continued exposure to these factors, coupled with the lack of control over other anthropogenic components, has promoted the maintenance of a chronic stress state in the studied coral community. Our findings highlight the need for the development of appropriate coastal management and conservation policies for the coral reefs of the Mexican Pacific Coast.


2007 ◽  
Vol 2007 ◽  
pp. 1-5 ◽  
Author(s):  
Mark H. Olson ◽  
Robert P. Jacobs ◽  
Eileen B. O'Donnell

Predators can be important top-down regulators of community structure and are known to have both positive and negative effects on species diversity. However, little is known about the reciprocal effects of species diversity on predators. Across a set of 80 lakes in Connecticut, USA, we found a strong positive correlation between prey species diversity (using the Shannon-Weiner Diversity Index) and growth rates of largemouth bass (Micropterus salmoides). This correlation was strongest for small predators and decreased with body size. Although the underlying mechanisms are not known, the correlation is not driven by total fish abundance, predator abundance, or productivity.


2004 ◽  
Vol 82 (4) ◽  
pp. 533-540 ◽  
Author(s):  
Shawn Morrison ◽  
Luc Barton ◽  
Peter Caputa ◽  
David S Hik

The effects of predation risk on foraging behavior often result in a trade-off between obtaining food and seeking shelter and may alter the selectivity of herbivores for individual plant species. We experimentally measured forage selection by a small alpine herbivore, the collared pika (Ochotona collaris (Nelson, 1893)), using a cafeteria-style arrangement of six potential forage species at five levels of predation risk. Contrary to our prediction, haying pikas did not switch preferences for forage species of different nutritional quality as predation risk increased. However, the total amount of forage removed was inversely related to risk, and the addition of cover at treatments of greatest potential risk ameliorated the negative effects of higher predation risk. The reasons for increased preference for poorer quality forage species in 2002 relative to 2000 are currently unknown but may reflect changes in predator abundance, forage quality, or increased competition for limited forage resources.


2017 ◽  
Vol 2 (2) ◽  
pp. 39
Author(s):  
I Wayan Winasa ◽  
Aunu Rauf

Side Effects of Deltamethrin Application to The Ground Surface Dwelling Predatory Arthropods on Soybean Field. Side effects of deltamethrin to the ground surface dwelling predatory arthropods were studied on soybean field in Cianjur during July to October 1998. Insecticide was applied 1-4 times. Predator abundance was observed by setting pitfall traps. The results showed that application of deltamethrin reduced the abundance of ground-surface predatory arthropods, especially lycosid and linyphiid spiders, carabid beetle and formicid. Reductions of predator abundance on the plots treated with deltamethrin were around 35% to 41%. There was no significant difference on the predator abundance among the plots treated with the insecticide at difference frequencies. Observations after application showed that predator abundance on the treated plots recovered one week after application. Deltamethrin application to the soybean with dense crown (38 and 52 days after planting) did not reduce predator abundance, especially within three day range after application. However, negative effects of deltamethrin application at early vegetative growth stage (10 days after planting) on the reduction of predator abundance continued by harvesting. The abundance of detritivorous arthropods was not affected by deltamethrin application.


2018 ◽  
Vol 62 (2) ◽  
pp. 97-107 ◽  
Author(s):  
Nina Keith

Abstract. The positive effects of goal setting on motivation and performance are among the most established findings of industrial–organizational psychology. Accordingly, goal setting is a common management technique. Lately, however, potential negative effects of goal-setting, for example, on unethical behavior, are increasingly being discussed. This research replicates and extends a laboratory experiment conducted in the United States. In one of three goal conditions (do-your-best goals, consistently high goals, increasingly high goals), 101 participants worked on a search task in five rounds. Half of them (transparency yes/no) were informed at the outset about goal development. We did not find the expected effects on unethical behavior but medium-to-large effects on subjective variables: Perceived fairness of goals and goal commitment were least favorable in the increasing-goal condition, particularly in later goal rounds. Results indicate that when designing goal-setting interventions, organizations may consider potential undesirable long-term effects.


Crisis ◽  
2013 ◽  
Vol 34 (5) ◽  
pp. 348-353 ◽  
Author(s):  
Hajime Sueki

Background: Previous studies have shown that suicide-related Internet use can have both negative and positive psychological effects. Aims: This study examined the effect of suicide-related Internet use on users’ suicidal ideation, depression/anxiety tendency, and loneliness. Method: A two-wave panel study of 850 Internet users was conducted via the Internet. Results: Suicide-related Internet use (e.g., browsing websites about suicide methods) had negative effects on suicidal ideation and depression/anxiety tendency. No forms of suicide-related Internet use, even those that would generally be considered positive, were found to decrease users’ suicidal ideation. In addition, our results suggest that the greater the suicidal ideation and feelings of depression and loneliness of Internet users, the more they used the Internet. Conclusion: Since suicide-related Internet use can adversely influence the mental health of young adults, it is necessary to take measures to reduce their exposure to such information.


Crisis ◽  
2020 ◽  
pp. 1-8
Author(s):  
Christian Ulrich Eriksen ◽  
Flemming Konradsen ◽  
Thilde Vildekilde

Abstract. Background: Information on methods of suicide is available online, and access to information on methods of suicide appears to contribute to a small but significant proportion of suicides. There is limited documentation of how methods of suicide are being profiled, as well as what content exists in other languages than English. Aim: We aimed to analyze and compare how methods of suicide are profiled on Danish and English-language websites. Method: We applied a categorization and content analysis of websites describing methods of suicide. Sites were retrieved by applying widely used Danish and English-language search terms. Results: A total of 136 English-language websites and 106 Danish-language websites were included for analysis. Websites were more often categorized as prevention or support sites, academic or policy sites, and against suicide sites than dedicated suicide sites (i.e., pro-suicide sites), or information sites. However, information on methods of suicide was available, and 20.1% and 8.9% of the English and Danish-language sites, respectively, suggested that a particular method of suicide was quick, easy, painless, or certain to result in death. Limitations: Only one author coded and analyzed all websites. A further operationalization of the content analysis checklist is warranted to increase reliability. Conclusion: The websites primarily had a prevention or anti-suicide focus, but information on methods of suicide was available, requiring an increased focus on how to diminish the negative effects of harmful online content.


2020 ◽  
Vol 25 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Amaia Del Campo ◽  
Marisalva Fávero

Abstract. During the last decades, several studies have been conducted on the effectiveness of sexual abuse prevention programs implemented in different countries. In this article, we present a review of 70 studies (1981–2017) evaluating prevention programs, conducted mostly in the United States and Canada, although with a considerable presence also in other countries, such as New Zealand and the United Kingdom. The results of these studies, in general, are very promising and encourage us to continue this type of intervention, almost unanimously confirming its effectiveness. Prevention programs encourage children and adolescents to report the abuse experienced and they may help to reduce the trauma of sexual abuse if there are victims among the participants. We also found that some evaluations have not considered the possible negative effects of this type of programs in the event that they are applied inappropriately. Finally, we present some methodological considerations as critical analysis to this type of evaluations.


2020 ◽  
Vol 19 (2) ◽  
pp. 86-96
Author(s):  
Isaac A. Lindquist ◽  
Emily E. Adams ◽  
Joseph A. Allen

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.


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