MSGID: 1:317/3 64a79538   
   PID: hpt/lnx 1.9.0-cur 2019-01-08   
   TID: hpt/lnx 1.9.0-cur 2019-01-08   
    Number cruncher calculates whether whales are acting weirdly    
      
     Date:   
         July 6, 2023   
     Source:   
         University of Copenhagen - Faculty of Science   
     Summary:   
         We humans can be a scary acquaintance for whales in the wild. This   
         includes marine biologists tagging them with measuring devices to   
         understand them better. These experiences can make whales behave   
         erratically for a while. Such behaviour can affect research quality   
         and highlights an animal ethics dilemma. Now, researchers have   
         figured out how to solve the problems with math.   
      
      
         Facebook Twitter Pinterest LinkedIN Email   
      
   ==========================================================================   
   FULL STORY   
   ==========================================================================   
   We humans can be a scary acquaintance for whales in the wild. This   
   includes marine biologists tagging them with measuring devices to   
   understand them better. These experiences can make whales behave   
   erratically for a while. Such behaviour can affect research quality and   
   highlights an animal ethics dilemma.   
      
   Now, University of Copenhagen researchers have figured out how to solve   
   the problems with math.   
      
   Maybe you have tried taking a howling pooch or cranky cat to the vet.   
      
   Regardless of your noblest intentions, your pet's experience may have   
   been equally unpleasant. Animals react to the unknown in their own   
   way. The case is no different for cetaceans like narwhal and bowhead   
   whales when they encounter human generated noises such as ship noise   
   or mining blasts in the North Atlantic -- or when they are caught by   
   well-meaning marine biologists who just want to get to know them better.   
      
   When biologists 'tag' whales with measuring devices, the animals react   
   by behaving unusually -- abnormally. For example, for a while after being   
   tagged, they may perform many atypical shallow dives and quick jerks. Such   
   behaviour is misleading when the goal is to study the animal's normal   
   and natural behaviour.   
      
   The problem is getting help from an unusual corner.   
      
   "Biologists seek to understand animals as natural beings, but their   
   reactions turn into unnatural behaviour that creates noise in the   
   dataset. Because of this, a lot of data from just after whales are   
   tagged ends up getting discarded. In this study, we have proposed a   
   mathematical approach using statistical methods that can determine   
   exactly how much data to keep," says PhD student Lars Reiter from the   
   Department of Mathematics.   
      
   Valuable for humans and animals alike With two statistical calculations,   
   the researcher has found a way to estimate when whales like narwhals   
   and bowhead whales will return to their natural behaviour after being   
   tagged. It is a method that can also be used to study how animals respond   
   to other types of disturbances.   
      
   "This research is extremely valuable to us as marine biologists who   
   are interested in the behaviour and well-being of whales. It provides   
   us with a standardised approach by which to distinguish between   
   natural behaviour and affected behaviour in whales. Thus far, we've   
   made individual estimates that are more or less spot on," says marine   
   biologist Outi Tervo from the Greenland Institute of Natural Resources,   
   who collaborated with the mathematicians on the study.   
      
   The statistical method allows researchers to avoid discarding too much   
   or too little data. If too much data is kept, it can interfere with the   
   research results, and if too much is lost, it comes at cost to both the   
   animals and humans.   
      
   "It really matters in terms of research, but also financially. And   
   not least, it means something for animal welfare. If we throw away   
   data unnecessarily, more whales will eventually have to go through the   
   experience for us to conduct this research, which is ultimately meant   
   to benefit the animals," says Outi Tervo.   
      
   Idea came from a parliamentary election Whale behaviour does not go from   
   abnormal to normal with a flick of its tail.   
      
   Their behaviour normalizes gradually, typically over a day -- and in   
   a few cases over a longer period of time. During this transition, a   
   whale's behaviour manifests itself on both sides of an area designated   
   as normal whale behaviour.   
      
   So how do scientists figure out where to make the cut?  "The idea came   
   to me while I was standing in the voting booth during parliamentary   
   elections. Borrowing from the logic of the electoral system, you can   
   consider it as if the whales -- or these data points which show the   
   whale's behaviour -- vote on whether they are in or out of their normal   
   range," explains Lars Reiter.   
      
   By recording 1 positive "vote" when the behaviour is within the normal   
   range, and 1 negative "vote" when outside, the scientists can add up   
   all the votes and find the moment at which the number of votes goes from   
   predominantly negative to positive.   
      
   The researchers use two approaches to determine normal whale behaviour. In   
   part, they look at the whale's diving pattern, as well as its acceleration   
   and fine motor skills.   
      
   How to calculate the behaviour of animals statistically Sometimes it hunts   
   in the deep, while at others times, it cruises quietly at the surface. The   
   activity that a whale is engaged in is crucial for understanding its   
   normal energy level. Lars Reiter's method takes this into account as   
   something new: "Where previous research focused on the mean behavior,   
   we instead situate a whale in an activity based on its movements --   
   where it is assessed based on a normal value for acceleration that   
   matches the speci?c activity being engaged in. We do this by using what   
   are known as quantiles, instead of averages, because they allow us to   
   focus on behavioural extremes. For example, hunting and resting are   
   opposing extremes in terms of energy levels," explains Lars Reiter.   
      
   When the focus is on the whale's diving profile, on the other hand,   
   you look at the pattern formed by the whale's overall activities. By   
   combining depth and time, one can assess whether the distribution of   
   different dive types is natural.   
      
   Wiser about the animals' hardships and better at avoiding them According   
   to the marine biologist, the data-based approach represented by the   
   statistical method also means that researchers can now develop better,   
   more gentle ways of tagging.   
      
   "Based on this study, we already know that the amount of time we spend   
   putting the equipment on is an important factor for how much the animals   
   are affected afterwards. Therefore, we can set up some time limits --   
   where we stop and set the whale free if it takes more than X number of   
   minutes allowed," says Outi Tervo.   
      
   A shift away from individual estimates to a mathematical standard could   
   also mean better assessments from the veterinary oversight that tag-using   
   research projects are required to go through.   
      
   "The method will make it so that ethical approval from a veterinary   
   inspection is more data-based and precise. So, there is no doubt that this   
   research is a step forward for animal welfare," says the marine biologist.   
      
   * Extra info: An important instrument for a future with less ice and   
   more people The natural Arctic habitat of narwhals and bowhead whales   
   is changing due to climate change. Annual ice shrinkage and increasing   
   human activity is taking place in areas that whales once had all to   
   themselves. The researchers' method can become an important instrument   
   and contribute to a greater understanding of the consequences.   
      
   "It allows us to study how whales are impacted by various human   
   activities.   
      
   They can be external sources of noise that we can situate in time and   
   location, such as a blast or a ship passing by. Or sounds and activities   
   that we emit ourselves. Lars' algorithm lets us get a clear picture of   
   how it all affects the animals," says Outi Tervo.   
      
   Increased activity will lead to more ocean noise, which is of concern   
   to marine biologists with regards to how it will affect large marine   
   animals like narwhal, which are incredibly sensitive to sound. Co-author   
   and supervisor Professor Susanne Ditlevsen believes that the studies   
   and new method will become more important in the years ahead.   
      
   "Climate change is leading to increased anthropogenic activity in Arctic   
   whale habitats. Melting ice means that areas which were once impassable   
   can now be reached by humans. We would like to assess whether it scares   
   and disturbs the animals, but it is not clear how. The new methods can   
   be used to assess at what distance from the animal habitat should various   
   activities take place," says Susanne Ditlevsen.   
      
   Facts: Statistical method with two mathematical calculations and one   
   intersection.   
      
   The statistical method can generally be understood as calculations with   
   two types of tagging data -- acceleration and depth, and a way of adding   
   it up that finds the optimal intersection.   
      
   1. Acceleration tells about the energy level and whale movements   
   ("jerks"). The indicators for natural behaviour are divided according   
   to whale activity, so that, for example, a high energy level is recorded   
   as natural in connection with hunting, but not in connection with rest.   
      
   2. The whale's diving profile is measured in depth and time spent on   
   a dive.   
      
   Temporal impacts over a 40-hour period show a pattern of different types   
   of dives -- e.g., U-dives, where the whale stay at depth for some time,   
   or V- dives, where the whale resurfaces quickly. The pattern is compared   
   with normal values measured after the 40 hours.   
      
   3. The cut-off point for when the whale is back in normal behaviour is   
   found by counting the individual measurements as "voting for or against"   
   normal behaviour. As such, the researchers find the optimal place to   
   divide the research data into natural and influenced behaviour.   
      
   About the study The study is part of a larger research collaboration   
   between the Greenland Institute of Natural Resources and the University   
   of Copenhagen's Department of Mathematics, that focuses on the Arctic's   
   large marine mammals.   
      
   The researchers include Lars Reiter Nielsen and Susanne Ditlevsen from the   
   University of Copenhagen, Outi M. Tervo and Mads Peter Heide-Jo/rgensen   
   from the Greenland Institute of Natural Resources and Susanna B. Blackwell   
   from Greeneridge Sciences, Inc., Santa Barbara, USA   
       * RELATED_TOPICS   
             o Plants_&_Animals   
                   # Dolphins_and_Whales # Marine_Biology # Animals #   
                   Sea_Life   
             o Computers_&_Math   
                   # Artificial_Intelligence # Statistics #   
                   Information_Technology # Mathematics   
       * RELATED_TERMS   
             o Baleen_whale o Right_whale o Blue_Whale o Sperm_Whale o   
             Whale o Dog_intelligence o Bowhead_Whale o Whale_song   
      
   ==========================================================================   
      
    Print   
      
    Email   
      
    Share   
   ==========================================================================   
   ****** 1 ****** ***** 2 ***** **** 3 ****   
   *** 4 *** ** 5 ** Breaking this hour   
   ==========================================================================   
       * First_Snapshots_of_Fermion_Pairs *   
       Why_No_Kangaroos_in_Bali;_No_Tigers_in_Australia   
       * New_Route_for_Treating_Cancer:_Chromosomes *   
       Giant_Stone_Artefacts_Found:_Prehistoric_Tools   
       * Astonishing_Secrets_of_Tunicate_Origins *   
       Most_Distant_Active_Supermassive_Black_Hole *   
       Creative_People_Enjoy_Idle_Time_More_Than_Others   
       * Restoring_Fragile_X_Protein_Production *   
       Earth's_Solid_Metal_Sphere_Is_'Textured' *   
       Elephants_Vary_Their_Dinner_Menu_Day-To-Day   
      
   Trending Topics this week   
   ==========================================================================   
   PLANTS_&_ANIMALS Biochemistry_Research Insects_(including_Butterflies)   
   Wild_Animals EARTH_&_CLIMATE Air_Pollution Ice_Ages Pollution   
   FOSSILS_&_RUINS Ancient_Civilizations Cultures Early_Climate   
      
      
   ==========================================================================   
      
   Strange & Offbeat   
   ==========================================================================   
   PLANTS_&_ANIMALS   
   Why_There_Are_No_Kangaroos_in_Bali_(and_No_Tigers_in_Australia)   
   Number_Cruncher_Calculates_Whether_Whales_Are_Acting_Weirdly   
   Fossils_Reveal_How_Ancient_Birds_Molted_Their_Feathers_--_Which_Could_Help   
   Explain_Why_Ancestors_of_Modern_Birds_Survived_When_All_the_Other_Dinosaurs   
   Died EARTH_&_CLIMATE   
   Why_There_Are_No_Kangaroos_in_Bali_(and_No_Tigers_in_Australia)   
   Turning_Old_Maps_Into_3D_Digital_Models_of_Lost_Neighborhoods   
   Squash_Bugs_Are_Attracted_to_and_Eat_Each_Other's_Poop_to_Stock_Their   
   Microbiome FOSSILS_&_RUINS   
   Giant_Stone_Artefacts_Found_on_Rare_Ice_Age_Site_in_Kent,_UK   
   How_Urea_May_Have_Been_the_Gateway_to_Life   
   Newly_Discovered_Jurassic_Fossils_in_Texas Story Source: Materials   
   provided by University_of_Copenhagen_-_Faculty_of_Science. Note: Content   
   may be edited for style and length.   
      
      
   ==========================================================================   
   Journal Reference:   
      1. Lars Reiter Nielsen, Outi M. Tervo, Susanna B. Blackwell, Mads Peter   
         Heide‐Jo/rgensen, Susanne Ditlevsen. Using quantile regression   
         and relative entropy to assess the period of anomalous behavior   
         of marine mammals following tagging. Ecology and Evolution, 2023;   
         13 (4) DOI: 10.1002/ece3.9967   
   ==========================================================================   
      
   Link to news story:   
   https://www.sciencedaily.com/releases/2023/07/230706124603.htm   
      
   --- up 1 year, 18 weeks, 3 days, 10 hours, 50 minutes   
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)   
   SEEN-BY: 15/0 106/201 114/705 123/120 153/7715 218/700 226/30 227/114   
   SEEN-BY: 229/110 112 113 307 317 400 426 428 470 664 700 291/111 292/854   
   SEEN-BY: 298/25 305/3 317/3 320/219 396/45 5075/35   
   PATH: 317/3 229/426