The dawn of migration science
It is October in Europe and the signs of change are in the air. The season of autumn is starting to set in and the leaves have changed their colors from green to yellow and red. It is a sign that the days will become shorter and winter is about to arrive soon. The change of seasons also announces the arrival of new guests at the lake of Konstanz located at the southern border of Germany and Switzerland. These guests are migrating birds that come from different corners of Eastern Europe and the Arctic region. Lake Konstanz is a large fresh water reservoir which is one of the many important locations that serve as a vital point for resting or feeding millions of birds during the migration season. The annual seasonal changes trigger the migration as the food resources in their breeding grounds become scarce during winter and the birds move towards the warmer climates. Every day hundreds of waterbirds are arriving at the lake e.g. Pochards, Tufted ducks and Shovelers etc. Waterbirds are not the only ones that migrate, there are also warblers and cuckoos, thrushes and swallows, storks and eagles.
Migration is a global phenomenon. Some of the birds coming to the lake of Konstanz stay throughout the winter or move forward towards the African continent. The migration route between Europe and Africa is known as the African-Eurasian Flyway. It is one of the many known migration routes used by millions of birds. The journey is long, there are many challenges and unknown dangers. Humans have observed the presence of animals for a long time. Many civilizations have recorded migration movement of animals and associated them with the changes in the seasons. In modern science, migration is pursued as a scientific subject to learn about different aspects of migration e.g. the origin of the behavior, it’s evolution and the mechanisms. Birds are not the only animals that migrate. In the oceans, marine animals such as whales and seals travel great distances much like turtles and eels. On land larger mammals like elephants and wildebeests take on to migration. Even insects move vast distances often crossing continents e.g. Dragonflies migrate from India to Africa and Monarch butterflies from the US to Mexico. Each migration has a story of it’s own.
Developing methods to track movement of animals across the globe is crucial. Their movements are closely connected to our lives and the environmental conditions. A rich bio-diverse environment is necessary for the survival of the flora and fauna on the planet. For example, insects provide a free service to us by pollinating flowers of many different trees. Similarly, bats and birds help the regeneration of forests by dispersal of seeds. These forests absorb the carbon dioxide from the environment and help to maintain a balanced temperature on our planet which allows all species to thrive. Slight shifts in the temperature can lead to melting of snow in polar regions causing variation in food supply for many birds. Consistent rise in global temperatures increase frequency of events such as wildfires or coral bleaching and result in catastrophic loss of wildlife. Animals respond to changes in climatic conditions and therefore keeping track of their movement patterns provide a deeper insight into the complex cycle of life on the planet.
Record Holders:
Insects:
Dragon Flies (Pantala flavescens) : 14,000–18,000 kilometers (Longest insect migration)
Birds:
Arctic Tern (Sterna paradisaea) : 70–95,000 kilometers, Arctic circle to Antarctic region (longest bird migration).
Amur Falcons (Falco amurensis) : 22,000 kilometers, Siberia to South Africa (Longest sea crossing raptor).
Bar tailed godwit (Limosa lapponica) : 24–25,000 kilometers, Alaska to New Zealand (Longest non-stop flight)
Mammals
Humpback Whales (Megaptera novaeangliae) : avg 8000 kilometers various parts of world (Record — 9800 kilometers Brazil to Madagascar)
The past
Scientists have used bio-logging to measure movement of animals. Bio-logging involves tagging animals with small sensors that can measure location (e.g. GPS), sample the environmental conditions such as temperature and pressure, and record physiological parameters such as heartbeat, wing beat frequency etc. Migration research using bio-logging has revealed fascinating stories about the amazing adaptations, survival strategies and the sense of orientation while travelling across wide landscapes. For example, bio-logging (GPS and acceleration) studies with white storks have revealed that social relationships are important for their survival: Juvenile storks follow the adults during their first migration and learn the technique of using wind thermals for long soaring flights. Monarch butterflies navigate hundreds of kms to reach the same patch of forest every year. Bio-loggers also tell us about the incredible endurance of the animals. Amur falcons make a 5 day long non-stop flight from India to the horn of Africa during its migration from Siberia to South Africa (approx 22000 kms return journey, including 5 day non-stop sea journey).
Bio-logging studies started with radio telemetry, where a small radio emitter is fixed on the animal and the proximity of the animals from the receiver is indicated with a sound. The receivers only locate the animals within the range of the tracking area. It is often difficult to keep up with animals, especially if they can fly. Latest bio-loggers have multiple smaller sensors such as GPS, acceleration, magnetometer, gyroscope, microphone etc. are available to record data with solar panels and battery. Nowadays, cell phone networks (GSM) are used to provide a larger communication range but they are limited in terms of geographical locations and data transmission rates. The sensors are deployed as per the need of the experiment. It is ideal to have sensors that are able to capture and transmit a wide range of data, consume less power and weigh less than 5% of the animal’s weight.
However, the existing technology for animal tracking is not sufficient for tracking global movement of many animals e.g. songs birds, insects and marine animals. There are two major challenges: sensor design ( data collection) and telecommunication (data transmission). This includes several technological challenges, such as developing smaller sensors and producing them at lower costs for widespread deployment.
The present
Prof. Martin Wikeslki is one of the leading experts on the topic of animal migration. He is one of the directors at the Max Planck Institute of Animal Behavior in Konstanz, Germany, and leads the migration department. He is project leader of the ICARUS initiative — International Cooperation for Animal Research Using Space. 17 years ago, Prof. Dr. Martin Wikelski and his colleagues proposed a unique concept to track the movement of animals across the globe using very small sensors that communicate directly using a satellite. The team realized the importance of having satellite tracking for studying migration at global scale but the idea was considered impossible at the time, hence the project was named ICARUS. The name comes from an ancient Greek fable about a boy, called Icarus, who attempted to fly using wings made of wax and feathers, but he flew too close to the sun which melted the wings and he ended up dropping into the ocean.
The story of the ICARUS project is turning out to be a positive one. Finally, the ICARUS team has managed to bring together technology developers, politicians, scientists, policy makers, space organizations and leaders of several nations to embark on this journey.
Currently, the International Space Station (ISS) is traveling at 350 km distance from the surface of the earth and at the speed of 27,724 kms/sec, carrying an antenna that is able to communicate with hundreds of sensors placed on small songbirds (Blackbirds) that are preparing to migrate across Europe. Scientists have recently completed pilot tests with the new ICARUS sensors and started the project after rigorous testing of the communication module between satellite antenna and the sensor. The Blackbird project is one of the first projects that will use the new tracking technology.
As part of the project, the ICARUS team has designed a completely new sensor that is lightweight (< 5gms) and solar operated. The sensor communicates directly with the antenna placed on the ISS in an energy efficient manner. The data from ISS is sent directly to the data center on earth and available for researchers through a website, called Movebank. Movebank, is one of the largest repositories specially made to store bio-logging data from all types of sensors. Generally, satellite communication requires a lot of power and a large antenna, for example, cell phone communication. A large device is not suitable for wildlife and to avoid this the ICARUS team developed a novel communication protocol and a special antenna to be placed on the ISS. The space agencies of Germany (DLR) and Russia (ROSCOSMOS) worked together to deploy the antenna on the ISS. The antenna and the computer were sent to the ISS in 2018 and various tests were performed in 2019.
The ICARUS project aims to reveal many hidden mysteries about the animal kingdom. The plan is to develop different versions of the ICARUS sensors that can be attached to mammals, marine animals, birds and insects of different sizes and shapes. The eventual vision of the project is to use the information obtained through the global movement of the animals and use this network as the internet of animals.
Why is this idea important? Firstly, such a network will help us answer fundamental questions like where do these animals go and what kind of environment they face during their migration. The information about the location of the animals and their preferred habitats is valuable for designing better protective measures. This includes policy making decisions and preventing illegal exploitation of wildlife via poaching and wildlife trading. For example, migratory studies are used to provide legal protection at international scale through the Convention on the conservation of Migratory Species (CMS) which is an environmental treaty of the United Nations with 131 signed members.
The internet of animals will allow us to look at several global problems in a different manner. Wild animals are losing their natural habitats to humans and hence coming more in contact with humans and their domestic animals. Increasing contact between the wild animals leads to new challenges such as human-wildlife conflicts, disease transmission and food safety. Predators like tigers, leopards or wolves are persecuted and poisoned because they hunt domestic animals. It is important to identify and mitigate such instances. Similarly, intercontinental movement of animals is closely linked to transmission of zoonotic diseases that transfer from wild animals to humans. It is important to have information about the origin of such diseases and trace the path of their transmission e.g. Nipah. Insects such as locust swarms destroy agricultural produce in some of the most underdeveloped regions of the world triggering massive food shortage and regional instability.
Prof. Wikelski wants to use the movement patterns of the animals as an early warning system to predict natural disasters. The central idea is to learn how animals have evolved to sense and avoid natural disasters. Recently, his team has demonstrated that domestic cattle with bio-loggers repeatedly show unusual movements up to 1–20 hrs before the earthquakes depending on their distance from the epicenter. In future, such methods may become commonplace for prediction of natural disasters. Furthermore, animals travel long distances and go to remote corners of the world from the north to the south pole and from east to west. The sensors carried by the animals will provide important measurements about the changing climatic conditions which are otherwise hard to obtain. It would allow us to determine whether our attempts at combating climate change are working or not. The Internet of animals will provide a new way of measuring the health of our environment and working on the environmental issues.
The future
There is still a long way to go for the ICARUS team. The existing deployment of ICARUS tags is limited to birds. The team is coming up with new designs for tagging big mammals and marine animals. The final challenge is to create very small tags (< 1 gms) to track insects such as locusts or dragonflies. At the same time, other collaborations are being developed to handle the large amount of data with machine learning and artificial intelligence as well as to monitor activity of multiple species simultaneously.
One of the broader objectives is to make the bio-logging technology and the data accessible to researchers across the globe. The cost of using ICARUS tags is expected to be less than existing methods. The data generated by the system will be open for scientists across the globe. This will facilitate many new collaborations and fuel an effort to work together to solve the global problems. The data will be accessible to citizens via a smartphone app called the Animal Tracker App. The app is already available and displays real-time movement of animals using the data from Movebank. In the future, it may be combined with citizen science projects and used for spreading awareness in the public domain.
In summary, we can say that we are indeed at the dawn of migration sciences. The new tools and technology will enhance our ability to make informed decisions and save many species from the brink of extinction. These actions will be decisive in our battle against climate change. Perhaps, It will also provide means for improving the quality of life for millions of people without causing substantial damage to the environment.