Impact of 17α-Ethynylestradiol Increase on Post-Spawning Mortality in the Female Siamese Fighting Fish
Water Air and Soil Pollution, Jun 1, 2021
17α-Ethynylestradiol (EE2) is a synthetic hormone that has become a widespread problem in the aqu... more 17α-Ethynylestradiol (EE2) is a synthetic hormone that has become a widespread problem in the aquatic environments. The immunomodulatory effects of EE2 in fish have attracted much attention in recent years; however, little is known about its immunotoxicological impacts. This study was conducted to investigate the immune function of female Siamese fighting fish exposed to an environmental concentration of EE2, 10 ng/L. Aggressive reproductive behavior in this species often results in injuries to females after spawning, and thus they are a good candidate in immunotoxic actions of EE2. Fish were exposed to EE2 for 15 days and then distributed for breeding. Immune function, pathogen resistance, and survival rate were assessed after spawning. Immune responses including serum concentrations of IgM, lysozyme, complement, and bactericidal activity were lower in EE2-exposed females than the control fish. Also, EE2-exposed females showed higher mortality rate regardless of whether they were challenged with the bacterium. These results suggest that EE2 suppressed immune responses of spawned female fighting fish, thereby reducing its potential to resist against opportunistic pathogens.
Comparative Cognition . By Mary C. Olmstead and Valerie A. Kuhlmeier. Cambridge and New York: Cambridge University Press. $135.00 (hardcover); $64.99 (paper). xi + 471 p.; ill.; index. ISBN: 978-1-107-01116-8 (hc); 978-1-107-64831-9 (pb). 2015
Storms can have significant impacts on wildlife and many animals, including birds, can predict a ... more Storms can have significant impacts on wildlife and many animals, including birds, can predict a storm's arrival and change their behaviour accordingly. Storms are often associated with changes in environmental variables, particularly with a fall in barometric pressure. Social animals may collectively detect and advertise the potential onset of inclement weather to facilitate group responses. The present study tested the hypothesis that the sulphur-crested cockatoo uses environmental cues to predict the onset of storms and communicates this to conspecifics by emitting a specific 'rain call'. Field observations were made over a four-month period at four locations in greater Sydney. Cockatoo calls were recorded, along with multiple environmental variables: barometric pressure, relative humidity, rainfall and temperature. We also noted the time of day relative to sunrise and sunset. We found that rain calls occurred throughout the day but were most prominent at dawn and were far more common at two of the four study sites. Rain calls were more likely to occur at slightly lower temperatures, during periods of high humidity and if it was currently raining. We found no evidence that the calls were prompted by current atmospheric pressure, but the observation period did not contain many storms.
Animal Sentience: An Interdisciplinary Journal on Animal Feeling, 2022
Sentience" means the capacity to feel, and feelings are private affairs. Sentience is hence extre... more Sentience" means the capacity to feel, and feelings are private affairs. Sentience is hence extremely difficult to quantify in nonhuman animals. We have no direct means of determining whether an animal is sentient. Thus we rely on a series of indirect measures or criteria which collectively provide some level of confidence about the probability that an animal is sentient. Crump et al. propose a modified framework based on 8 criteria for estimating the likelihood of sentience in a target taxon. Whereas I very much like their proposed framework, I would suggest a couple of amendments that may improve it further: a weighting for each criterion and the addition of a "data insufficient" category (to differentiate lack of evidence from evidence of lack).
Urban river catchments are often severely affected by human activities but may still retain signi... more Urban river catchments are often severely affected by human activities but may still retain significant biodiversity. Surprisingly little is known about the behaviour of urban fishes, even those popular with anglers. Key environmental variables that trigger fish behaviour, such as river flow, are highly affected by instream structures including weirs and changes in the natural flow regime. Here, we used acoustic telemetry to examine the movements of Australian bass in a river located in suburban Sydney, Australia. We found that fish tended to be nocturnally active, however, small-scale movements were highly idiosyncratic and less associated with river flow than other factors. Larger-scale movements associated with spawning migrations were strongly correlated with winter floods. Half of the tagged fish migrated to the confluence of the river with Sydney Harbour to breed. Their return migration was hampered by a weir, but the provision of a new fish way facilitated successful return to freshwater at high tide. Despite occupying a highly affected, urban catchment fish behaviour showed similarity to those occupying more natural drainages. Our results highlight the importance of maintaining natural river flows in urban catchments and sustaining fish movement and migration capabilities through the installation of appropriate fish passage devices.
Tony Trewavas of Edinburgh University claims that plants have the power to compute, show foresigh... more Tony Trewavas of Edinburgh University claims that plants have the power to compute, show foresight and remember what happens to them, to such a degree that it may be regarded as underpinning a novel form of intelligence. The only real difference between plants and animals is the ...
For full list of author affiliations and declarations see end of paper Context. Gamay is a coasta... more For full list of author affiliations and declarations see end of paper Context. Gamay is a coastal waterway of immense social, cultural and ecological value. Since European settlement, it has become a hub for industrialisation and human modification. There is *Correspondence to: growing desire for ecosystem-level management of urban waterways, but such efforts are often T. P. Stelling-Wood School of Life and Environmental Sciences, challenged by a lack of integrated knowledge. Aim and methods. We systematically reviewed
bioRxiv (Cold Spring Harbor Laboratory), Aug 1, 2022
Detailed observational research on free-ranging species of marine megafauna is required to unders... more Detailed observational research on free-ranging species of marine megafauna is required to understand their behavioural ecology, including how groups respond to environmental and anthropogenic pressures. New technologies are opening up potential for research on these species in the wild, especially on group-based and collective behaviours. Reef manta rays (Mobula alfredi) are socially interactive elasmobranchs that form groups in coastal reef habitats. Collective behaviours are likely important to their fitness, but may be disturbed by humans. Using small, remotely-piloted drones, we performed aerial observations of manta ray groups in Raja Ampat, West Papua. We empirically quantified patterns of collective movement including relative spatial positions, alignment, speed and leadership positions of conspecifics. We found unique patterns of spatial positioning, alignment and leadership, including differences between sexes, and high levels of local attraction, which were suggestive of distinct collective behaviour states. We suggest that 'rules of interaction' in manta rays vary at the individual level and can shift depending on local environmental and social conditions. Leader-follower behaviour likely has broad importance to cohesive movement and social behaviour in M. alfredi. We suggest that further studies on manta ray movement should consider utilising models of collective motion that capture group-level behavioural processes.
Impact of 17α-Ethynylestradiol Increase on Post-Spawning Mortality in the Female Siamese Fighting Fish
Water Air and Soil Pollution, Jun 1, 2021
17α-Ethynylestradiol (EE2) is a synthetic hormone that has become a widespread problem in the aqu... more 17α-Ethynylestradiol (EE2) is a synthetic hormone that has become a widespread problem in the aquatic environments. The immunomodulatory effects of EE2 in fish have attracted much attention in recent years; however, little is known about its immunotoxicological impacts. This study was conducted to investigate the immune function of female Siamese fighting fish exposed to an environmental concentration of EE2, 10 ng/L. Aggressive reproductive behavior in this species often results in injuries to females after spawning, and thus they are a good candidate in immunotoxic actions of EE2. Fish were exposed to EE2 for 15 days and then distributed for breeding. Immune function, pathogen resistance, and survival rate were assessed after spawning. Immune responses including serum concentrations of IgM, lysozyme, complement, and bactericidal activity were lower in EE2-exposed females than the control fish. Also, EE2-exposed females showed higher mortality rate regardless of whether they were challenged with the bacterium. These results suggest that EE2 suppressed immune responses of spawned female fighting fish, thereby reducing its potential to resist against opportunistic pathogens.
Comparative Cognition . By Mary C. Olmstead and Valerie A. Kuhlmeier. Cambridge and New York: Cambridge University Press. $135.00 (hardcover); $64.99 (paper). xi + 471 p.; ill.; index. ISBN: 978-1-107-01116-8 (hc); 978-1-107-64831-9 (pb). 2015
Storms can have significant impacts on wildlife and many animals, including birds, can predict a ... more Storms can have significant impacts on wildlife and many animals, including birds, can predict a storm's arrival and change their behaviour accordingly. Storms are often associated with changes in environmental variables, particularly with a fall in barometric pressure. Social animals may collectively detect and advertise the potential onset of inclement weather to facilitate group responses. The present study tested the hypothesis that the sulphur-crested cockatoo uses environmental cues to predict the onset of storms and communicates this to conspecifics by emitting a specific 'rain call'. Field observations were made over a four-month period at four locations in greater Sydney. Cockatoo calls were recorded, along with multiple environmental variables: barometric pressure, relative humidity, rainfall and temperature. We also noted the time of day relative to sunrise and sunset. We found that rain calls occurred throughout the day but were most prominent at dawn and were far more common at two of the four study sites. Rain calls were more likely to occur at slightly lower temperatures, during periods of high humidity and if it was currently raining. We found no evidence that the calls were prompted by current atmospheric pressure, but the observation period did not contain many storms.
Animal Sentience: An Interdisciplinary Journal on Animal Feeling, 2022
Sentience" means the capacity to feel, and feelings are private affairs. Sentience is hence extre... more Sentience" means the capacity to feel, and feelings are private affairs. Sentience is hence extremely difficult to quantify in nonhuman animals. We have no direct means of determining whether an animal is sentient. Thus we rely on a series of indirect measures or criteria which collectively provide some level of confidence about the probability that an animal is sentient. Crump et al. propose a modified framework based on 8 criteria for estimating the likelihood of sentience in a target taxon. Whereas I very much like their proposed framework, I would suggest a couple of amendments that may improve it further: a weighting for each criterion and the addition of a "data insufficient" category (to differentiate lack of evidence from evidence of lack).
Urban river catchments are often severely affected by human activities but may still retain signi... more Urban river catchments are often severely affected by human activities but may still retain significant biodiversity. Surprisingly little is known about the behaviour of urban fishes, even those popular with anglers. Key environmental variables that trigger fish behaviour, such as river flow, are highly affected by instream structures including weirs and changes in the natural flow regime. Here, we used acoustic telemetry to examine the movements of Australian bass in a river located in suburban Sydney, Australia. We found that fish tended to be nocturnally active, however, small-scale movements were highly idiosyncratic and less associated with river flow than other factors. Larger-scale movements associated with spawning migrations were strongly correlated with winter floods. Half of the tagged fish migrated to the confluence of the river with Sydney Harbour to breed. Their return migration was hampered by a weir, but the provision of a new fish way facilitated successful return to freshwater at high tide. Despite occupying a highly affected, urban catchment fish behaviour showed similarity to those occupying more natural drainages. Our results highlight the importance of maintaining natural river flows in urban catchments and sustaining fish movement and migration capabilities through the installation of appropriate fish passage devices.
Tony Trewavas of Edinburgh University claims that plants have the power to compute, show foresigh... more Tony Trewavas of Edinburgh University claims that plants have the power to compute, show foresight and remember what happens to them, to such a degree that it may be regarded as underpinning a novel form of intelligence. The only real difference between plants and animals is the ...
For full list of author affiliations and declarations see end of paper Context. Gamay is a coasta... more For full list of author affiliations and declarations see end of paper Context. Gamay is a coastal waterway of immense social, cultural and ecological value. Since European settlement, it has become a hub for industrialisation and human modification. There is *Correspondence to: growing desire for ecosystem-level management of urban waterways, but such efforts are often T. P. Stelling-Wood School of Life and Environmental Sciences, challenged by a lack of integrated knowledge. Aim and methods. We systematically reviewed
bioRxiv (Cold Spring Harbor Laboratory), Aug 1, 2022
Detailed observational research on free-ranging species of marine megafauna is required to unders... more Detailed observational research on free-ranging species of marine megafauna is required to understand their behavioural ecology, including how groups respond to environmental and anthropogenic pressures. New technologies are opening up potential for research on these species in the wild, especially on group-based and collective behaviours. Reef manta rays (Mobula alfredi) are socially interactive elasmobranchs that form groups in coastal reef habitats. Collective behaviours are likely important to their fitness, but may be disturbed by humans. Using small, remotely-piloted drones, we performed aerial observations of manta ray groups in Raja Ampat, West Papua. We empirically quantified patterns of collective movement including relative spatial positions, alignment, speed and leadership positions of conspecifics. We found unique patterns of spatial positioning, alignment and leadership, including differences between sexes, and high levels of local attraction, which were suggestive of distinct collective behaviour states. We suggest that 'rules of interaction' in manta rays vary at the individual level and can shift depending on local environmental and social conditions. Leader-follower behaviour likely has broad importance to cohesive movement and social behaviour in M. alfredi. We suggest that further studies on manta ray movement should consider utilising models of collective motion that capture group-level behavioural processes.
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