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| Tracking system | Basic principle | Main examples of usage | Main advantages | Main constraints | Usage in marine animals |
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| Capture-recapture | Tagging an animal and waiting for its recovery somewhere | Bird migration overland; fish migration | Easy to apply | Recapture rate often very low. Only general movement information provided | Only in special cases (fishery-targeted species) |
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| Acoustic- or radio-tracking | Localizations obtained by collecting signals produced by radio transmitters (VHF range) or by sound-emitting devices | Tracking of large mammals or of birds (VHF); fish tracking (acoustic) | Applicable to small animals; relatively inexpensive | Requires short-range contact with tracked animal; useful only for short distance movements | Short-range tracking of non-air breathing animals (e.g., fish or large invertebrates) |
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Light level loggers
(geolocators) | Localizations obtained by processing light level information recorded at various times of the day. The information can be stored in an on-board memory (loggers) or retransmitted to satellites (pop-up tags) | Loggers: tracking of bird movements; pop-up tags: fish tracking. | Loggers: small and simple instruments; allow localizations even of animals that do not surface | Coarse localization precision (around 100 km); not applicable in some periods (equinoxes) and areas (arctic regions, equator). Need to recovery the loggers | Tracking of long-range movements in non-air breathing animals (especially fishes) |
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| GPS loggers | Localizations obtained through signals received from geostationary GPS satellites and stored in an internal memory | Birds during short scale movements (e.g., foraging trips) | Great temporal and spatial precision | Need to recovery the instrument to get the data. Do not work underwater; difficult to use in surfacing animals | Tracking of foraging trips in seabirds and of internesting movements in turtles |
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| Satellite telemetry (Argos) | Localizations obtained by UHF signals sent by special transmitters to low-orbit satellites of the Argos system | Migratory movements in medium-to large-size species | Easiness of usage and efficiency in data collection | High costs for transmitters and satellite system. Do not work underwater | Wealth of examples in turtles, seabirds and pinnipeds. Increasingly used in cetaceans and surfacing fish |
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