A light level geolocator, light-level logger or global location sensor (GLS) is a lightweight, electronic archival tracking device, usually used in bird migration research to map migration routes, identify important staging areas, and sometimes provide additional ecological information. A geolocator periodically records ambient light level (solar irradiance) to determine location.
Mathematical formulas for calculating global positions based on sunset and sunrise were first described by Gemma Frisius in 1530. Due to the lack of accurate clocks, his theoretical work could not be applied for two centuries before John Harrison produced a sufficiently accurate clock. Animal tracking using light level data appears to have been first carried out on elephant seals. [1] Although not described until 1992, the first device to be developed was reportedly in 1989 as an adaptation of a TDR (time-depth recorder) and called a geographic location, time-depth recorder (GLTDR) weighing 196g. [2] Also in 1992 was a publication by a different group with a similar design (weight 113g) who called it a global location sensor (GLS) though no field use was mentioned. [3]
The use of dedicated light level recorders for tracking birds was pioneered in the 1990s by engineer, Vsevolod Afanasyev, and scientists at the British Antarctic Survey (BAS) who first developed a device in an attempt to record the movements of juvenile wandering albatross during the many years between fledging and returning to their colony to breed. [4] [5] From albatrosses and other seabirds the use of geolocators has been extended to other migratory species, including waders, wildfowl, raptors and songbirds as designs have become gradually smaller and more energy efficient. [6] [7]
Light level geolocators primarily use an electronic light sensor to record light level and may also make other measurements to aid geolocation (e.g. temperature or water immersion). The smallest are archival types that do not use satellite or radio telemetry to offload data, and recapture of the bird is necessary to obtain the data. The disadvantage of having to recapture is offset by the miniature size to which archival loggers can be made. By using low power design techniques and data compression they can record data for long periods of time. [8]
Recording light levels over time produces data that can be used to calculate latitude and longitude readings of a bird's long-distance movements. The traditionally used 'threshold analysis method' requires only twilight data accurately time-stamped. Typically, daylight length (the time between dawn and dusk) is used to determine latitude, while the mid-time between a dawn and dusk is used to determine longitude. In this way, two position fixes can be obtained daily. Other analysis techniques can include analysis of the dawn and dusk curve (rate of change of light), or use the noon light level to attempt cloud compensation. The location data so derived is not as accurate as that from GPS or PTT (platform transmitter terminal) tracking involving satellites, but the devices can be made considerably lighter and cheaper. Other sensors, such as for recording temperature, or whether the logger is wet or dry, may be used in conjunction with the light-level logging in order to provide further ecological information. The devices may be attached to the bird being tracked by a harness, or to the band on the bird's leg. The weights of geolocators range from 0.3g upwards, with a battery life of 6 months to 5 years. [9]
The main accuracy limitation of light level geolocation is due to the uncertainty in the amount of attenuation of the ambient light level at any particular time. Light attenuation can have many causes e.g. cloud, feathers, foliage, topography. Because of this, the quality of the resulting location calculations varies with species, tag attachment technique, habitat and behaviour.
Instrumentation is a collective term for measuring instruments, used for indicating, measuring, and recording physical quantities. It is also a field of study about the art and science about making measurement instruments, involving the related areas of metrology, automation, and control theory. The term has its origins in the art and science of scientific instrument-making.
Automatic vehicle location is a means for automatically determining and transmitting the geographic location of a vehicle. This vehicle location data, from one or more vehicles, may then be collected by a vehicle tracking system to manage an overview of vehicle travel. As of 2017, GPS technology has reached the point of having the transmitting device be smaller than the size of a human thumb, able to run 6 months or more between battery charges, easy to communicate with smartphones — all for less than $20 USD.
A data logger is an electronic device that records data over time or about location either with a built-in instrument or sensor or via external instruments and sensors. Increasingly, but not entirely, they are based on a digital processor, and called digital data loggers (DDL). They generally are small, battery-powered, portable, and equipped with a microprocessor, internal memory for data storage, and sensors. Some data loggers interface with a personal computer and use software to activate the data logger and view and analyze the collected data, while others have a local interface device and can be used as a stand-alone device.
In computing, Internet geolocation is software capable of deducing the geographic position of a device connected to the Internet. For example, the device's IP address can be used to determine the country, city, or ZIP code, determining its geographical location. Other methods include examination of Wi-Fi hotspots, a MAC address, image metadata, or credit card information.
The grey-headed albatross also known as the gray-headed mollymawk, is a large seabird from the albatross family. It has a circumpolar distribution, nesting on isolated islands in the Southern Ocean and feeding at high latitudes, further south than any of the other mollymawks. Its name derives from its ashy-gray head, throat and upper neck.
In marketing, geomarketing is a discipline that uses geolocation in the process of planning and implementation of marketing activities. It can be used in any aspect of the marketing mix — the product, price, promotion, or place. Market segments can also correlate with location, and this can be useful in targeted marketing.
Albatrosses, of the biological family Diomedeidae, are large seabirds related to the procellariids, storm petrels, and diving petrels in the order Procellariiformes. They range widely in the Southern Ocean and the North Pacific. They are absent from the North Atlantic, although fossil remains show they once occurred there and occasional vagrants are found. Albatrosses are among the largest of flying birds, and species of the genus Diomedea have the longest wingspans of any extant birds, reaching up to 3.7 m (12 ft). The albatrosses are usually regarded as falling into four genera, but disagreement exists over the number of species.
A positioning system is a system for determining the position of an object in space. One of the most well-known and commonly used positioning systems is the Global Positioning System (GPS).
Animal migration tracking is used in wildlife biology, conservation biology, ecology, and wildlife management to study animals' behavior in the wild. One of the first techniques was bird banding, placing passive ID tags on birds legs, to identify the bird in a future catch-and-release. Radio tracking involves attaching a small radio transmitter to the animal and following the signal with a RDF receiver. Sophisticated modern techniques use satellites to track tagged animals, and GPS tags which keep a log of the animal's location. With the Emergence of IoT the ability to make devices specific to the species or what is to be tracked is possible. One of the many goals of animal migration research has been to determine where the animals are going; however, researchers also want to know why they are going "there". Researchers not only look at the animals' migration but also what is between the migration endpoints to determine if a species is moving to new locations based on food density, a change in water temperature, or other stimulus, and the animal's ability to adapt to these changes. Migration tracking is a vital tool in efforts to control the impact of human civilization on populations of wild animals, and prevent or mitigate the ongoing extinction of endangered species.
Animal migration is the relatively long-distance movement of individual animals, usually on a seasonal basis. It is the most common form of migration in ecology. It is found in all major animal groups, including birds, mammals, fish, reptiles, amphibians, insects, and crustaceans. The cause of migration may be local climate, local availability of food, the season of the year or for mating.
GPS animal tracking is a process whereby biologists, scientific researchers, or conservation agencies can remotely observe relatively fine-scale movement or migratory patterns in a free-ranging wild animal using the Global Positioning System (GPS) and optional environmental sensors or automated data-retrieval technologies such as Argos satellite uplink, mobile data telephony or GPRS and a range of analytical software tools.
An indoor positioning system (IPS) is a network of devices used to locate people or objects where GPS and other satellite technologies lack precision or fail entirely, such as inside multistory buildings, airports, alleys, parking garages, and underground locations.
Wi-Fi positioning system is a geolocation system that uses the characteristics of nearby Wi‑Fi access point to discover where a device is located.
Pop-up satellite archival tags (PSATs) are used to track movements of marine animals. A PSAT is an archival tag that is equipped with a means to transmit the collected data via the Argos satellite system. Though the data are physically stored on the tag, its major advantage is that it does not have to be physically retrieved like an archival tag for the data to be available making it a viable, fishery independent tool for animal behavior and migration studies. They have been used to track movements of ocean sunfish, marlin, blue sharks, bluefin tuna, swordfish and sea turtles to name a few species. Location, depth, temperature, oxygen levels, and body movement data are used to answer questions about migratory patterns, seasonal feeding movements, daily habits, and survival after catch and release, for examples.
A data storage tag (DST), also sometimes known as an archival tag, is a combination of a data logger and multiple sensors that record data at predetermined intervals. DSTs usually have a large memory size and a long lifetime: most are supported by batteries that allow the tag to record positions for several years. Alternatively some tags are solar powered and allow the scientist to set their own interval; this then allows data to be recorded for significantly longer than battery-only powered tags.
A shock data logger or vibration data logger is a measurement instrument that is capable of autonomously recording shocks or vibrations over a defined period of time. Digital data is usually in the form of acceleration and time. The shock and vibration data can be retrieved, viewed and evaluated after it has been recorded.
A temperature data logger, also called temperature monitor, is a portable measurement instrument that is capable of autonomously recording temperature over a defined period of time. The digital data can be retrieved, viewed and evaluated after it has been recorded. A data logger is commonly used to monitor shipments in a cold chain and to gather temperature data from diverse field conditions.
The history of wildlife tracking technology involves the evolution of technologies that have been used to monitor, track, and locate many different types of wildlife. Many individuals have an interest in tracking wildlife, including biologists, scientific researchers, and conservationists. Biotelemetry is "the instrumental technique for gaining and transmitting information from a living organism and its environment to a remote observer".
Geolocator may refer to:
Photovoltaic system performance is a function of the climatic conditions, the equipment used and the system configuration. PV performance can be measured as the ratio of actual solar PV system output vs expected values, the measurement being essential for proper solar PV facility's operation and maintenance. The primary energy input is the global light irradiance in the plane of the solar arrays, and this in turn is a combination of the direct and the diffuse radiation.