Washington: Social hunting strategies are already well documented in many animal species when prey is distributed in an unpredictable way across the landscape. Researchers have now demonstrated for the first time that animals in this case the common noctule bat join together and form a mobile sensory network in order to increase their chances of finding their prey. The analyses show that predators can adjust to variable environmental conditions through flexible foraging strategies by networking with conspecifics.
Many predators need to find food on a daily basis. If the prey is irregularly distributed across the landscape and only available for a short time, this task seems like searching for the needle in a haystack. Animals that depend on such unpredictable prey have therefore often developed social strategies for foraging: During the search for prey, individuals are in contact with each other and exchange information about their environment. An international research team led by the University of Potsdam and Leibniz-IZW has now observed for the first time that common noctule bats (Nyctalus noctula) temporarily join together to form mobile, sensory networks while foraging. "The common noctule is particularly well suited for such investigations because its prey -- swarms of insects -- disperse completely unpredictably in open airspace," explains the paper's lead author, Manuel Roeleke. "Moreover, the distance over which the bats can locate the insects via ultrasound is relatively small, about 10 to 15 metres. This makes it difficult for them to track their prey. On the other hand, the bats can perceive their own conspecifics over much greater distances, under ideal conditions up to 160 metres. Searching in a group should therefore be more successful."
In total, the scientists analysed the flight patterns of 81 common noctule bats. This was made possible by small radio transmitters that send signals to an array of antennas. Florian Jeltsch from the University of Potsdam explains: "With the state-of-the-art 'ATLAS' system, we can simultaneously record the movement of dozens of individual animals. Thanks to the great support of local farmers and private landowners, we have been able to operate the tracking technology in the Uckermark district in Eastern Germany since 2018 -- a unique opportunity to study animal movements and biodiversity in the European agricultural landscape." His colleague Christian Voigt from Leibniz-IZW adds: "With the 'ATLAS' system, it is now possible to record the interactions of bats in flight. Our data confirm the theory of mobile sensory networks: During the search for insects, the bats fan out but remain in acoustic contact and, if necessary, adjust their flight paths to one another in order to search as large an area as possible." If an individual bat in the network finds a swarm of prey insects, its neighbours are informed of this via changes in flight movements and via ultrasonic calls specifically used for insect hunting. This gradually makes all animals in the sensory network aware of the rewarding hunting area.
The scientific team compared the foraging efficiency of "networked" bats and of individual hunters as a function of group size and food distribution. In order to achieve this, they used a computer model developed by co-author Cara Gallagher using the empirically determined movement patterns. "Networking and exchanging information proved particularly useful for the bats when food sources were widely distributed in space," Roeleke explains. "Thus, our model showed that 'networked' animals needed 40 percent less time to track down prey than bats that ignored their conspecifics while foraging." By foraging in groups, bats can find prey even in large-scale cultivated landscapes and thereby also effectively contribute to the control of agricultural insect "pests." If this is to continue in the future, the bats require consistent protection, particularly their system of roosts. When local populations become too small in numbers, the bats can no longer form efficient networks. As solitary animals, it is then difficult for them to find food quickly and reliably. —ANI

Social hunting strategies are already well documented in many animal species when prey is distributed in an unpredictable way across the landscape.

Bats Communicate And Work Together For More Efficient Foraging

The Birds

Chennai : PETA India had earlier awarded the forest department with a Hero to Animals Award in April in a gesture to thank them for rescuing four parrots that were being illegally sold online for astrology scams as well as for and for aiding in the arrest of two men who were allegedly involved, reported&nbsp;IANS."PETA India commends the Chengalpattu Forest Department for saving these beautiful parakeets, who should never have been caught and who deserve to fly free again. Buying, selling, or caging parakeets is illegal and can result in a jail term of up to three years or a fine of up to Rs 25,000 or both," said&nbsp;<a href="https://www.timesnownews.com/topic/meet-ashar" rel="noopener noreferrer" target="_blank" style="color: var(--hrefTextColor-1);">Meet Ashar</a>, PETA India's manager of cruelty response projects."Caged birds have nothing to sing about. Birds belong in the sky, never in cages, and we urge anyone who is keeping a bird in this way to turn them into a local forest department or an animal protection group for rehabilitation and to be reunited with a flock. In the illegal bird trade, countless birds are torn away from their families and denied everything that is natural and important to them so that they can be sold as ‘pets or bogus "fortune-tellers’.Fledglings are often snatched from their nests, while other birds panic as they're caught in traps or nets that can seriously injure or kill them as they struggle to break free.Captured birds are packed into small boxes, and an estimated 60 percent of them die in transit from broken wings and legs, thirst, or sheer panic. Those who survive face a bleak, lonely life in captivity, suffering from malnutrition, loneliness, depression, and stress”, PETA India noted. --- IANS

PETA India had earlier awarded the forest department with a Hero to Animals Award in April in a gesture to thank them for rescuing four parrots that were being illegally sold online for astrology scams as well as for and for aiding in the arrest of two men who were allegedly involved.

Tamil Nadu: Forest Department rescue illegally held parakeets following PETA complaint

Washington: According to a recent on how heat impacts the behaviour and physiology of Zebra finches revealed that heat altered the activity of hundreds of genes in the testis, but fewer in the brain, also suggesting that the brain may be less responsive to extreme temperatures. The research helps to provide some insights into birds and their ability to handle the threat of climate change."Most of what we know about the behavioural and physiological effects of heat comes from aquatic organisms or terrestrial cold-blooded animals, but heat waves could be a real problem for terrestrial birds and mammals too, especially if heat interferes with critical components of their reproductive behaviour and physiology," said Sara Lipshutz, assistant professor at Loyola University Chicago, former graduate student at UT, and first author on the publication. "We wanted to understand how that happens as a first step towards understanding how to manage these problems. "Heat waves can be lethal for warm-blooded animals, but behavioural and physiological effects are missing from recent high-profile studies on climate change. The researchers wanted to know about sub-lethal effects of heat that do not kill animals but still might impact their ability to adapt and thrive as the climate changes.Lipshutz and colleagues exposed zebra finches to a four-hour heat challenge, similar to what wild birds might experience during the afternoon heat on a summer day. Zebra finches were selected for the study because these songbirds experience extreme temperature fluctuations in their native Australia.The team measured heat effects on thermoregulatory behavior and looked specifically at how heat changed gene activity in tissues that are critical to reproduction -- the testis that control fertility and a part of the brain that regulates singing, which is an essential mate-attraction behavior in birds. They discovered that heat altered the activity of hundreds of genes in the testis, but fewer in the brain, suggesting that the brain may be less responsive to extreme temperatures.&nbsp;"At the same time, we found evidence that dopamine-related signalling was affected in the brain, meaning that even sub-lethal heat may change a bird's ability to reproduce, via changes in motivational circuits for song production," Lipshutz said. "If they can't sing, or sing well, they aren't going to breed." Bird populations have been dramatically declining over the past few decades, and male songbirds need to sing to attract a mate. Coupled with previous studies showing that birds sing less during heat, this project reveals potential underlying mechanisms by which heat may contribute to avian population declines."It's really a triple-whammy," said Derryberry, corresponding author on the publication. "Heat's not only affecting their brains, but it also appears to affect testicular gene networks related to self-maintenance and sperm production. So, there's potentially less motivation to sing, reduced gonadal function, and greater investment in self-maintenance, all of which can detract from successful reproduction."The study also provided some hopeful insights for birds and their ability to handle the threat of climate change. Males that panted more often during the heat challenge exhibited more limited effects on gene activity in the brain and testis."For a long time, researchers have reasoned that behavioral flexibility might be key for animals' ability to handle novel environmental challenges," said Kimberly Rosvall, associate professor of biology at IU Bloomington, whose lab oversaw that genomic side of this project. "We saw that some individuals better used behavioral thermoregulation to dissipate the physiological effects of heat. If animals are able to adjust their behavior. or if behavior can evolve to keep pace with climate change, birds may be able to adapt."&nbsp;According to Lipshutz, the results have important implications for sexual selection in a warming world as well."Some individuals, or even some species, may perform well under extreme temperatures," she said. "That could influence both how thermal tolerance evolves and how behavior evolves too."&nbsp;—ANI

 According to a recent on how heat impacts the behaviour and physiology of Zebra finches revealed that heat altered the activity of hundreds of genes in the testis, but fewer in the brain, also suggesting that the brain may be less responsive to extreme temperatures. The research helps to provide some insights into birds and their ability to handle the threat of climate change.

Study Reveals How Heat Waves Could Lead To Avian Population Decline

Washington: A new research from the Oxford Flight Group using computer simulations and Hollywood-style motion capture shows how birds optimise their landing manoeuvres for an accurate descent.Researchers at the University of Oxford have found that hawks control their flight to ensure the safest landing conditions when perching, even if it takes longer and more energy to do so. Understanding how birds optimise their landing manoeuvres through learning may help in developing small aircraft capable of perching like birds.In new research published in Nature, four Harris' hawks wearing tiny retroreflective markers were tracked flying back and forth between two perches. Their precise movements were recorded by 20 motion capture cameras positioned around the room, allowing the research team to reconstruct their flight paths on over 1,500 flights. The research team then used computer simulations to understand why the birds chose their particular path to the perch.Aircraft have the luxury of using a runway for braking after landing to reduce speed. In contrast, birds must brake before they arrive at the perch -- however slowing down to a safe speed while in flight risks stall, leading to a sudden loss of flight control. The researchers discovered that the hawks follow a flight path that slows them down to a safe speed but minimises the distance from the perch at which they stall.To minimise stall, the hawks dived downwards while flapping, before spreading their wings into a gliding posture as they swooped up to the perch. By selecting just the right speed and position from which to swoop up to the perch, the birds were already within grabbing distance of the perch when they stalled, keeping their landings as safe and controllable as possible.Co-lead author Dr Lydia France, Department of Biology, University of Oxford said: 'We found that our birds weren't optimising either the time or energy spent, so their swooping trajectories were neither the shortest nor cheapest options for getting from A to B. Instead, our birds were reducing the distance from the perch at which they stalled and were even better at limiting stall than our simplified computer model.''The three juvenile birds flew directly between the perches by flapping for the first few flights of their familiarisation period but soon adopted the indirect swooping behaviour characteristic of experienced birds,' explained co-lead author Dr Marco KleinHeerenbrink, Department of Biology, University of Oxford.Landing is a critical manoeuvre, and stalling has been the cause of many aircraft accidents. Looking at birds and asking how they solve the problem of safe landing might help us find new bioinspired design solutions for our own technologies, including small aircraft capable of perching like birds.Understanding how birds learn complex motor tasks like landing might also help improve artificial intelligence (AI). When aircraft engineers use computers to solve the problem of perching using a trial-and-error approach to refine the data, it can take tens of hundreds of hours to find an answer. Yet, hawks find an optimised solution over a handful of flights, showing the gap that still exists between natural and artificial intelligence.'Motion capture technology has allowed us to analyse thousands of flights at a time, tackling questions that we never could have done before. Looking forward, this opens the tantalising possibility of understanding how animals learn complex motor tasks, like learning to fly, and of revolutionising how robotic systems can do the same,' said senior author Professor Graham Taylor.&nbsp;&nbsp;—ANI

 A new research from the Oxford Flight Group using computer simulations and Hollywood-style motion capture shows how birds optimise their landing manoeuvres for an accurate descent.

Birds Optimize Their Landing Maneuvers For Accurate Descent: Research

Birds Optimize Their Landing Maneuvers For Accurate Descent : Research

Washington: A new study that examines how heat impacts the behaviour and physiology of Zebra finches found that heat altered the activity of hundreds of genes in the testis, but fewer in the brain, suggesting that the brain may be less responsive to extreme temperatures. The study also provided some hopeful insights into birds and their ability to handle the threat of climate change."Most of what we know about the behavioural and physiological effects of heat comes from aquatic organisms or terrestrial cold-blooded animals, but heat waves could be a real problem for terrestrial birds and mammals too, especially if heat interferes with critical components of their reproductive behaviour and physiology," said Sara Lipshutz, assistant professor at Loyola University Chicago, former graduate student at UT, and first author on the publication. "We wanted to understand how that happens as a first step towards understanding how to manage these problems."Heat waves can be lethal for warm-blooded animals, but behavioural and physiological effects are missing from recent high-profile studies on climate change. The researchers wanted to know about sub-lethal effects of heat that do not kill animals but still might impact their ability to adapt and thrive as the climate changes.Lipshutz and colleagues exposed zebra finches to a four-hour heat challenge, similar to what wild birds might experience during the afternoon heat on a summer day. Zebra finches were selected for the study because these songbirds experience extreme temperature fluctuations in their native Australia. The team measured heat effects on thermoregulatory behavior and looked specifically at how heat changed gene activity in tissues that are critical to reproduction -- the testis that control fertility and a part of the brain that regulates singing, which is an essential mate-attraction behavior in birds. They discovered that heat altered the activity of hundreds of genes in the testis, but fewer in the brain, suggesting that the brain may be less responsive to extreme temperatures. "At the same time, we found evidence that dopamine-related signalling was affected in the brain, meaning that even sub-lethal heat may change a bird's ability to reproduce, via changes in motivational circuits for song production," Lipshutz said. "If they can't sing, or sing well, they aren't going to breed." Bird populations have been dramatically declining over the past few decades, and male songbirds need to sing to attract a mate. Coupled with previous studies showing that birds sing less during heat, this project reveals potential underlying mechanisms by which heat may contribute to avian population declines."It's really a triple-whammy," said Derryberry, corresponding author on the publication. "Heat's not only affecting their brains, but it also appears to affect testicular gene networks related to self-maintenance and sperm production. So, there's potentially less motivation to sing, reduced gonadal function, and greater investment in self-maintenance, all of which can detract from successful reproduction."The study also provided some hopeful insights for birds and their ability to handle the threat of climate change. Males that panted more often during the heat challenge exhibited more limited effects on gene activity in the brain and testis."For a long time, researchers have reasoned that behavioral flexibility might be key for animals' ability to handle novel environmental challenges," said Kimberly Rosvall, associate professor of biology at IU Bloomington, whose lab oversaw that genomic side of this project. "We saw that some individuals better used behavioral thermoregulation to dissipate the physiological effects of heat. If animals are able to adjust their behavior. or if behavior can evolve to keep pace with climate change, birds may be able to adapt." According to Lipshutz, the results have important implications for sexual selection in a warming world as well. "Some individuals, or even some species, may perform well under extreme temperatures," she said. "That could influence both how thermal tolerance evolves and how behavior evolves too."&nbsp;—ANI

 A new study that examines how heat impacts the behaviour and physiology of Zebra finches found that heat altered the activity of hundreds of genes in the testis, but fewer in the brain, suggesting that the brain may be less responsive to extreme temperatures. 