| 1. |
- Andersson, Mathias H., et al.
(författare)
-
Displacement effects of ship noise on fish population : FP7 - Collaborative Project n° 314227 WP 4: Sensitivity of marine life to shipping noise Task 4.2.1
- 2015
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Ship induced noise is one of the major contributors to the elevated noise levels in the world’s oceans today. However, the knowledge about the impact on marine organisms is still scarce. Especially the effects on fish behaviour needs to be studied as fish are a fundamental part of the oceans ecosystem. Direct measurement of fish behaviour in the open sea area is technically difficult but needs to be done in order to estimate reaction thresholds and scales of any reaction. This experiment studies the long term behavioural reaction by wild cod (Gadus morhua) to ship noise and describes the character and scale of the reaction. This study took place on the Swedish west coast with a small local cod population and the area is normally without any large vessel traffic. For the ship disturbance, the Swedish Coast Guard ship KBV 032 was hired and passed thru the area nine times during three days. During the three days of ship noise exposure, the noise levels increased well above the ambient noise. The ship signature was what could be expected in terms of spectral level with most radiated noise energy between 100 - 500 Hz. The ship had a higher source level than expected (232 dB re 1μPa at 1 m, 10 - 300 Hz) but this was deliberate as the crew was asked to use the propellers in a non-optimal way to generate as much noise as possible. The result was a lot of broadband cavitation pulses generated by the ship. Then a noise footprint model was created and used in the estimates of received levels (exposure level) by the individual fish in the area based on the most probable location. It was clear in the transmission loss varied between the two sites where at the shallow site, the noise was attenuated more compared to the deep site. This is probably caused by the quite complicated propagation pattern. Also, the acoustically different bottom properties will affect the transmission loss in the area. In total, 39 cod (Gadus morhua) were caught by hand jigging and were fitted with internal acoustical tags. Bottom mounted receivers were deployed covering the area where the cod were known to inhabit. This study was designed to capture more large scale movements of hundreds of meters and not startle responses to the ship noise. Out of the 39 tagged fish, 17 and 18 fish met the set quality criterion for the short time behaviour analysis and 23 fish for long time behaviour to be included in the analysis. Some fish met the quality criteria for both the short and long term analysis. The other fish were either eaten by seals, caught by fishermen, left the area or had a malfunctioning tag. In general, the noticed reaction in terms of horizontal swimming were much smaller than expected and what the study was designed for. This results was surprising as the sound pressure levels the fish were exposed to would, based on the literature, cause a strong behaviour response in the fish. The movement was not in any large scale that would affect their energy consumption and affect their long term survival. This study was able to track fish with an accuracy of less than 10 m and estimates an interval of received noise level. This is one of the first studies of its kind that is tracking free swimming fish over a long period of time during an acoustic disturbance.
|
|
| 2. |
- Andersson, Marica, et al.
(författare)
-
Increased noise levels cause behavioural and distributional changes in Atlantic cod and saithe in a large public aquarium—A case study
- 2023
-
Ingår i: Aquaculture, Fish and Fisheries. - : John Wiley & Sons. - 2693-8847.
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract Investigating the effects of underwater noise on aquatic animals is a research field that is receiving rapidly increasing attention. Despite this, surprisingly few studies have addressed the potential impacts of noise in a marine animal husbandry setting. In this regard, the behaviour of fish in public aquariums can be used as an indicator of well-being, and noise is known to cause behavioural changes. This case study investigates the behaviour of cod (Gadus morhua) and saithe (Pollachius virens) in a large public aquarium when exposed to increased noise levels originating from an aquarium renovation carried out by construction divers. Swimming behaviour, group formation and vertical distribution, along with yawning and scratching frequencies of the fish, were analysed from video recordings made before, during and after the exposure to increased noise levels. The same parameters were also analysed to evaluate potential effects of the presence of divers when not making renovation noise, compared to fish behaviour prior to the renovation. There was a slight change in the depth distribution of both species and a decrease in the number of scratches in cod due to the presence of divers that were not making renovation noise. In the presence of construction noises in the tank, however, both cod and saithe showed a wider array of behavioural changes, including increased swimming speed, changes in depth distribution and increased yawning frequencies. The results from this case study demonstrate that an underwater renovation with increased noise levels impacts fish behaviour and suggests that underwater noise should be considered during the management of aquatic environments, including public aquaria.
|
|
| 3. |
- Blom, Eva-Lotta, 1973, et al.
(författare)
-
Acoustic and visual courtship traits in two sympatric marine Gobiidae species – Pomatoschistus microps and Pomatoschistus minutus
- 2016
-
Ingår i: Environmental Biology of Fishes. - : Springer Science and Business Media LLC. - 0378-1909 .- 1573-5133. ; 99, s. 999-1007
-
Tidskriftsartikel (refereegranskat)abstract
- Divergence in courtship traits across species can evolve as adaptations to different environments, and also through avoidance of reproductive interference and character displacement. Differences may also be explained by phylogenetic relationships. We compared different courtship traits, including male courtship sounds, in two sympatric Pomatoschistus species. Both species are characterised by having male and female courtship, and paternal care of eggs in nests under mussel shells and rocks. In addition to presenting novel observations, we reviewed the literature on courtship traits for both species and complemented it with new observations. We found that courting males of the common goby P. microps sing louder and produce sounds of shorter duration than males of the sand goby P. minutus. Furthermore, males of P. microps swim faster towards females during courtship than males of P. minutus. The eyes of P. minutus females turn black during courtship attempts, whereas this is not the case for females of P. microps. Species-specific differences in courtship sounds and behavior may lead to different susceptibility of the two species to environmental change such as noise pollution and turbidity.
|
|
| 4. |
- Blom, Eva-Lotta, et al.
(författare)
-
Anthropogenic noise disrupts early-life development in a fish with paternal care
- 2024
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 935
-
Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic noise is a global pollutant but its potential impacts on early life-stages in fishes are largely unknown. Here, using controlled laboratory experiments, we tested for impacts of continuous or intermittent exposure to low-frequency broadband noise on early life-stages of the common goby (Pomatoschistus microps), a marine fish with exclusive paternal care. Neither continuous nor intermittent noise exposure had an effect on filial cannibalism, showing that males were capable and willing to care for their broods. However, broods reared in continuous noise covered a smaller area and contained fewer eggs than control broods. Moreover, although developmental rate was the same in all treatments, larvae reared by males in continuous noise had, on average, a smaller yolk sac at hatching than those reared in the intermittent noise and control treatments, while larvae body length did not differ. Thus, it appears that the increased consumption of the yolk sac reserve was not utilised for increased growth. This suggests that exposure to noise in early life-stages affects fitness-related traits of surviving offspring, given the crucial importance of the yolk sac reserve during the early life of pelagic larvae. More broadly, our findings highlight the wide-ranging impacts of anthropogenic noise on aquatic wildlife living in an increasingly noisy world.
|
|
| 5. |
- Blom, Eva-Lotta, et al.
(författare)
-
Continuous and intermittent noise has a negative impact on reproductive success and early life survival in marine fish
- 2022
-
Konferensbidrag (refereegranskat)abstract
- Anthropogenic underwater noise is a global pollutant of increasing concern and its effect on marine organisms is largely unknown. Importantly, direct assessments of fitness consequences are lacking especially in fish. The effect of noise pattern with continuous or intermittent noise are poorly understood and the few existing studies investigating the effect highlight contradictory responses in fish. Working in aquaria, we experimentally tested the impact of broadband noise exposure (similar frequency range as anthropogenic boat noise; added either continuously or intermittently) on the behaviour and reproductive success, assessed by the number of obtained eggs, of the common goby (Pomatoschistus microps), a vocal fish with exclusive paternal care. The continuous noise treatment had the most detrimental effect by reducing spawning probability and females took longer to spawn under continuous noise. Males exposed to continuous noise got significantly fewer egg clutches (4 compared to 11 and 15 in the intermittent noise and silence treatments). Clutch area did not differ among treatments but clutches in the intermittent and continuous noise treatment had significantly more eggs per cm2. In addition, eggs in the control tanks hatched earlier than in the intermittent and noisy treatments. Larvae reared in continuous noise treatment were larger and had a smaller yolk-sac at hatching than larvae in the intermittent noise treatment and the control. Taken together, we show that noise, particularly a continuous noise exposure, negatively affects reproductive success and early life survival in fish larvae.
|
|
| 6. |
- Blom, Eva-Lotta, 1973, et al.
(författare)
-
Continuous but not intermittent noise has a negative impact on mating success in a marine fish with paternal care
- 2019
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic underwater noise is a global pollutant of increasing concern but its impact on reproduction in fish is largely unknown. Hence, a better understanding of its consequences for this important link to fitness is crucial. Working in aquaria, we experimentally tested the impact of broadband noise exposure (added either continuously or intermittently), compared to a control, on the behaviour and reproductive success of the common goby (Pomatoschistus microps), a vocal fish with exclusive paternal care. Compared to the intermittent noise and control treatments, the continuous noise treatment increased latency to female nest inspection and spawning and decreased spawning probability. In contrast, many other female and male pre-spawning behaviours, and female ventilation rate (proxies for stress levels) did not differ among treatments. Therefore, it is likely that female spawning decisions were delayed by a reduced ability to assess male acoustic signals, rather than due to stress per se and that the silent periods in the intermittent noise treatment provided a respite where the females could assess the males. Taken together, we show that noise (of similar frequency range as anthropogenic boat noise) negatively affects reproductive success, particularly under a continuous noise exposure.
|
|
| 7. |
- Blom, Eva-Lotta, 1973, et al.
(författare)
-
Male acoustic display in the sand goby – Essential cue in female choice, but unaffected by supplemental feeding
- 2022
-
Ingår i: Journal of Experimental Marine Biology and Ecology. - : Elsevier. - 0022-0981 .- 1879-1697. ; 556
-
Tidskriftsartikel (refereegranskat)abstract
- Many teleost fishes use acoustic and visual signalling during courtship. Such displays may convey information about body condition. Here we experimentally altered body condition of sand goby (Pomatoschistus minutus) males to examine effects on acoustic and visual courtship and subsequent spawning decisions. Over two weeks, males fed in excess were fed daily, whereas food-deprived males were fed once a week. Females only spawned with males that produced courtship sound. However, there were no treatment effects on the occurrence of spawning and males fed in excess did not invest more in visual or acoustic courtship than food-deprived males. That said, males fed in excess built more well-covered nests, with more sand piled on top, compared to food-deprived males. Male condition measured as lipid content differed significantly between treatments. However, only males fed in excess differed in lipid content from wild caught males, indicating that in nature, males are of similar condition to males in the low condition treatment group. Apart from the importance of courtship sound, the only male or female behaviour predicting reproductive success was if male displayed in the nest opening. Males often produce courtship sounds together with a visual display in this position. A female dark-eye display did not associate with reproductive success which, together with previous results, suggest a non-ornamental function of this trait. We conclude that male courtship sounds appear to be crucial in female mate choice, but the information content of the courtship sounds and how it relates to male condition remains elusive.
|
|
| 8. |
|
|
| 9. |
- Darehed, David, et al.
(författare)
-
Diurnal variations in the quality of stroke care in Sweden
- 2019
-
Ingår i: Acta Neurologica Scandinavica. - : Hindawi Limited. - 0001-6314 .- 1600-0404. ; 140:2, s. 123-130
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: A recent study of acute stroke patients in England and Wales revealed several patterns of temporal variation in quality of care. We hypothesized that similar patterns would be present in Sweden and aimed to describe these patterns. Additionally, we aimed to investigate whether hospital type conferred resilience against temporal variation. Materials and Methods: We conducted this nationwide registry-based study using data from the Swedish Stroke Register (Riksstroke) including all adult patients registered with acute stroke between 2011 and 2015. Outcomes included process measures and survival. We modeled time of presentation as on/off-hours, shifts, day of week, 4-hour, and 12-hour time blocks. We studied hospital resilience by comparing outcomes across hospital types. Results: A total of 113 862 stroke events in 72 hospitals were included. The process indicators and survival all showed significant temporal variation. Door-to-needle (DTN) time within 30 minutes was less likely during nighttime than daytime (OR 0.50; 95% CI 0.41-0.60). Patients admitted during off-hours had lower odds of direct stroke unit (SU) admission (OR 0.72; 95% CI 0.70-0.75). 30-day survival was lower in nighttime vs daytime presentations (OR 0.90, 95% CI 0.84-0.96). The effects of temporal variation differed significantly between hospital types for DTN time within 30 minutes and direct SU admission where university hospitals were more resilient than specialized non-university hospitals. Conclusions: Our study shows that variation in quality of care and survival is present throughout the whole week. We also found that university hospitals were more resilient to temporal variation than specialized non-university hospitals.
|
|
| 10. |
- Darehed, David, 1986-, et al.
(författare)
-
In-hospital delays in stroke thrombolysis : every minute counts
- 2020
-
Ingår i: Stroke. - : American Heart Association. - 0039-2499 .- 1524-4628. ; 51:8, s. 2536-2539
-
Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose: Intravenous thrombolysis is a well-established treatment for acute ischemic stroke. Our aim was to quantify the effect of each minute delay in door-to-needle time (DNT) on 90-day survival, intracerebral hemorrhagic complication <36 hours, and functional outcomes at 3 months, in routine clinical practice.Methods: Our nationwide registry-based study included 14 132 adult patient admissions with ischemic stroke receiving intravenous thrombolysis from 2010 to 2017. Outcomes were analyzed using multivariable logistic regression, adjusting for potential confounders.Results: Median DNT was 47 minutes, with an improvement from 65 to 38 minutes during the study. Median age was 74 years, and median National Institutes of Health Stroke Scale 8 points. We found a significant impact of each minute delay in DNT with reduced odds of survival by 0.6%, increased odds of intracerebral hemorrhagic and worse activities of daily living by 0.3%, and worse living conditions and mobility by 0.4%.Conclusions: Improving DNT is a key factor in achieving good outcomes after stroke. We estimate that in Sweden alone in 2017, compared with 2010, the shorter DNT achieved have saved 38 lives, avoided 8 intracerebral hemorrhagic transformations, and spared, respectively, 36, 51, and 52 patients from a worsening in activities of daily living, living conditions, and mobility. DNT is sensitive for interventions and should be targeted in quality improvement efforts.
|
|
| 11. |
- Darehed, David, 1986-
(författare)
-
The impact of organizational and temporal factors on acute stroke care in Sweden
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Acute stroke carries a high risk of morbidity and death, but early treatment can improve outcomes. Intravenous stroke thrombolysis (IVT) is one such treatment, it is however time-sensitive and show better outcomes the sooner it is given. Most studies on time to IVT so far have looked at fixed time-intervals, and studies of short delays in clinical practice are relatively scarce. Another well-established treatment is managing acute stroke patients in stroke units (SU). Admission rates to a SU as first destination of hospital care have improved over time in Sweden. In the past decade however, the rates have leveled out at around 75-80% without further improvement. A hypothesis is that in-hospital overcrowding contributes. Previous studies have shown that outcomes after stroke differ between hospital types, and also vary depending on time of admission, with higher mortality seen for off-hours, weekend and winter admissions. The reasons behind temporal variations are not fully understood, but it has been proposed that environmental, patient-related and organizational factors contribute. The overall aim of this thesis was to study the effect of organizational factors on quality of care and outcomes after stroke, primarily focusing on the role of in-hospital overcrowding, in-hospital time to IVT and time of admission, while also studying differences between hospitals.Methods: All papers in this thesis were based on data from the Swedish stroke register (Riksstroke), a national quality register that holds data on patient related factors, acute care and outcomes. Paper I included 13,955 patient admissions from 14 hospitals in Region Norrbotten and Region Skåne from 2011-2014, enriched with data on in-hospital bed occupancy. Papers II-IV included all 72 Swedish hospitals caring for patients with acute stroke. Paper II included data from 2011-2015 (N=113,862), paper III from 2011-2016 (N=132,744) and paper IV from 2010-2017 (N=14,132). Analyses included descriptive statistics, unadjusted analyses and multivariable adjusted analyses.Results: We found that each percent increase in in-hospital bed occupancy above 85% decreased admission rates to a SU as first destination of hospital care by 1.5% (odds ratio (OR) 0.985, 95% confidence interval (CI) 0.978-0.992), with significant differences between hospitals. Admission rates were also lower off-hours, compared to on-hours (OR 0.73, 95% CI 0.70-0.75). Over time, admission rates to a SU as first destination of hospital care decreased in university hospitals, while they increased in specialized non-university hospitals and community hospitals. Each minute delay in door-to-needle time (DNT) decreased the odds of 90-day survival by 0.6% (OR 0.994, 95% CI 0.992-0.996), increased the odds of ICH within 36 hours by 0.3% (OR 1.003, 95% CI 1.000-1.006), and led to significantly higher odds of a worsening in functional outcomes at 3 months by 0.3-0.4%. DNT within 30 minutes was most likely daytime, and varied between hospital types. 90-day survival was lowest for patients admitted in January (81.5%), and highest for those admitted in May (84.1%) (OR 1.28, 95% CI 1.17-1.40).Conclusion: We found that in-hospital overcrowding decrease admission rates to a SU as first destination of hospital care, and that even short delays in DNT decreases survival, increases ICH complications and leads to a worsening in functional outcomes in routine clinical practice. We also found that quality of care varied depending on time of admission and between hospitals, indicating unequal care. Organizational differences should be accessible through quality improvement efforts aiming to implement robust local guidelines for in-hospital stroke treatment.
|
|
| 12. |
- Darehed, David, et al.
(författare)
-
Time Trends and Monthly Variation in Swedish Acute Stroke Care
- 2019
-
Ingår i: Frontiers in Neurology. - : Frontiers Media SA. - 1664-2295. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose: Studies of monthly variation in acute stroke care have led to conflicting results. Our objective was to study monthly variation and longitudinal trends in quality of care and patient survival following acute stroke.Methods: Our nationwide study included all adult patients (≥18 years) with acute stroke (ischemic or hemorrhagic), admitted to Swedish hospitals from 2011 to 2016, and that were registered in The Swedish Stroke Register (Riksstroke). We studied how month of admission and longitudinal trends affected acute stroke care and survival. We also studied resilience to this variation among hospitals with different levels of specialization. Results: We included 132,744 stroke admissions. The 90-day survival was highest in May and lowest in January (84.1 vs. 81.5%). Thrombolysis rates and door-to-needle time within 30 min increased from 2011 to 2016 (respectively, 7.3 vs. 12.8% and 7.7 vs. 28.7%). Admission to a stroke unit as first destination of hospital care was lowest in January and highest in June (78.3 vs. 80.5%). Stroke unit admission rates decreased in university hospitals from 2011 to 2016 (83.4 vs. 73.9%), while no such trend were observed in less specialized hospitals. All the differences above remained significant (p < 0.05) after adjustment for possible confounding factors. Conclusion: We found that month of admission and longitudinal trends both affect quality of care and survival of stroke patients in Sweden, and that the effects differ between hospital types. The observed variation suggests an opportunity to improve stroke care in Sweden. Future studies ought to focus on identifying the specific factors driving this variation, for subsequent targeting by quality improvement efforts.
|
|
| 13. |
- Olsson, Karin H., 1979, et al.
(författare)
-
Dark eyes in female sand gobies indicate readiness to spawn
- 2017
-
Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 12:6
-
Tidskriftsartikel (refereegranskat)abstract
- In animals, colorful and conspicuous ornaments enhance individual attractiveness to potential mates, but are typically tempered by natural selection for crypsis and predator protection. In species where males compete for females, this can lead to highly ornamented males competing for mating opportunities with choosy females, and vice versa. However, even where males compete for mating opportunities, females may exhibit conspicuous displays. These female displays are often poorly understood and it may be unclear whether they declare mating intent, signal intrasexual aggression or form a target for male mate preference. We examined the function of the conspicuous dark eyes that female sand gobies temporarily display during courtship by experimentally testing if males preferred to associate with females with artificially darkened eyes and if dark eyes are displayed during female aggression. By observing interactions between a male and two females freely associating in an aquarium we also investigated in which context females naturally displayed dark eyes. We found that dark eyes were more likely to be displayed by more gravid females than less gravid females and possibly ahead of spawning, but that males did not respond behaviorally to dark eyes or prefer dark-eyed females. Females behaving aggressively did not display dark eyes. We suggest that dark eyes are not a signal per se but may be an aspect of female mate choice, possibly related to vision.
|
|
| 14. |
- Sallnäs Pysander, Eva-Lotta, et al.
(författare)
-
Navigation and control in haptic applications shared by blind and sighted users
- 2006
-
Ingår i: Haptic And Audio Interaction Design, Proceedings. - Glasgow : Springer. - 3540375953 ; , s. 68-80
-
Konferensbidrag (refereegranskat)abstract
- Haptic feedback in shared virtual environments can potentially make it easier for a visit ally impaired person to take part in and contribute to the process of group work. In this paper a task driven explorative evaluation is presented. of collaboration between visually impaired and sighted persons in three applications that provide haptic and visual feedback. The results show that all pairs could perform all the tasks in these applications even though a number of difficulties were identified. The conclusions made can inform design of applications for cooperation between visually impaired and sighted users.
|
|
| 15. |
- Svensson, Ola, 1971-, et al.
(författare)
-
Sand goby females do not spawn with silent males - but do males sing out their condition and can female hear the song in a noisy environment?
- 2022
-
Konferensbidrag (refereegranskat)abstract
- Males of sand gobies (Pomatoschistus spp.) spawn in shallow water and produce a courtship sound to entice females to spawn. Previous work on field-caught males shows that courtship sounds differ between males of different body condition and between species suggesting that females use acoustic information in mate choice. Here, we manipulated male body condition via feeding regimes and measured courtship and subsequent spawning decisions. Although male condition measured as lipid content differed significantly between feeding regimes, neither male visual courtship, acoustic courtship nor spawning success were affected. However, comparing the lipid content of the experimental males to field-caught males show that in nature, males are of similar condition to males in the low condition treatment group. Acoustic signals might be masked by anthropogenic noise. Thus, to test if noise may affect spawning success we exposed courting males to experimental noise, resembling boat noise. We found that females only spawned with males that produced courtship sounds and significantly less often when exposed to noise. We conclude that the information content of male courtship sound and how it relates to male condition remains elusive, but that acoustic courtship is essential for mating success, making sand gobies potentially vulnerable to noise pollution. These results will be discussed in the light of preliminary data from a field experiment using the same noise set-up where male mating success was unaffected by treatment, and a pond experiment where variation in male mating success was affected by low levels of playback noise.
|
|
| 16. |
|
|
