An Advanced, Low-Cost, GPS-Based Animal Tracking System

doi:10.2111/05-162R.1

Rangeland Ecology & Management

Volume 59, Issue 3, May 2006, Pages 334-340

https://doi.org/10.2111/05-162R.1 Get rights and content

Abstract

An improved global positioning system (GPS)–based animal tracking system is needed to meet quickly evolving demands of ecological research, range livestock production, and natural resource management. Commercially available tracking systems lack the data storage capacity needed to frequently collect animal location data (e.g., 15-minute intervals or less) over long-term deployment periods (e.g., 1 year or more). Some commercial systems have remote data–download capabilities, reducing the need to recapture tagged animals for data retrieval, but these systems download data via satellite (Argos), global system for mobile communications (GSM) cellular telephone, or telemetry radio frequencies. Satellite systems are excessively expensive, and GSM cellular coverage is extremely limited within the United States. Radio-based systems use narrow-band very-high– or ultra-high frequencies requiring the user to obtain frequency allocations. None of these existing systems were designed to provide continual, real-time data access. The Clark GPS Animal Tracking System (Clark ATS) was developed to meet the evolving demands of animal ethologists, ecologists, natural resource managers, and livestock producers. The Clark ATS uses memory-card technology for expandable data storage from 16 megabytes to 8 gigabytes. Remote data downloading and program uploading is accomplished using spread-spectrum radio transceivers, which do not require narrow-band radio frequency allocations. These radios also transmit, at a user-defined time interval, a real-time, GPS-location beacon to any Clark ATS base station within range (about 24 km or 15 miles line of sight). Advances incorporated into the Clark ATS make it possible to evaluate animal behavior at very fine spatial- and temporal-resolution over long periods of time. The real-time monitoring provided by this system enables researchers to accurately examine animal distribution and activity responses to acute, short-term disturbances relative to longer-term behavioral patterns. The Clark ATS also provides a huge time- and cost-savings to researchers and natural resource managers attempting to relocate a tagged animal in the field for direct observation or other operations.

Resumen

Se necesita un sistema mejorado de rastreo de animales basado en GPS para satisfacer las crecientes demandas de investigación ecológica, producción de ganado en pastizales y el manejo de los recursos naturales. Los sistemas de rastreo comerciales disponibles carecen de la capacidad de almacenaje de datos necesaria para colectar frecuentemente la localización del animal (por ejemplo, a intervalos de 15 minutos o menos) en un período largo de tiempo (un año o mas). Algunos sistemas comerciales tienen capacidad de descargar datos a larga distancia, reduciendo la necesidad de recapturar los animales marcados para recuperar los datos, pero estos sistemas descargan los datos vía satélite (Argos), a través de telefonía celular GSM o de radiofrecuencias de telemetría. Los sistemas de satélite son excesivamente caros y la cobertura de la telefonía celular GSM es extremadamente limitada dentro de Estados Unidos de América. Los sistemas basados en radio usan bandas estrechas de frecuencia VHF o UHF, requiriendo que el usuario obtenga asignaciones de frecuencia. Ninguno de los sistemas existentes fueron diseñados para proveer un acceso continuo en tiempo real. El Sistema de Rastreo de Animales Clark GPS (Clark ATS) fue desarrollado para satisfacer las demandas de los etólogos animal, ecólogos, manejadores de recursos naturales y productores de ganado. El Clark ATS utiliza tecnología de tarjeta de memoria para expandir la capacidad de almacenaje de datos de 16 megabytes a 8 gigabytes. La descarga remota de datos y la carga del programa se logra usando radio transcriptores de espectro amplio, que no requieren la asignación de frecuencias de radio de banda angosta. Estos radios también transmiten, a un intervalo de tiempo definido por el usuario, en tiempo real, la localización de la baliza de GPS a cualquier base de Clark ATS dentro del rango (aproximadamente 24 km o 15 millas en línea recta). Los avances incorporados al Clark ATS hacen posible evaluar el comportamiento animal a una resolución espacial y temporal muy fina por largos períodos de tiempo. El monitoreo en tiempo real suministrado por este sistema permite a los investigadores examinar acertadamente la distribución de los animales y las actividades en respuesta a disturbios severos a corto plazo en relación a los patrones de comportamiento a largo plazo. El Clark ATS también proporciona grandes ahorros de tiempo y costos a los investigadores y manejadores de recursos naturales que intentan relocalizar en el campo a los animales marcados para realizar observaciones directas u otras operaciones.

Section snippets

INTRODUCTION

Study of animal ecology using telemetry tracking systems began in the late 1950s and early 1960s (Le Munyan et al. 1959; Eliassen 1960; Marshall et al. 1962; Cochran and Lord 1963; Mech et al. 1965) using collars or tags emitting very-high frequency (VHF) radio-signal pulses. Intensive monitoring of widely roaming animals with VHF systems, however, was costly, time-consuming, and often posed risks to personnel safety. With the launch of the Nimbus 3 satellite (Kenward 1987) and, later, the

Clark GPS Animal Tracking System

The Clark ATS consists of a GPS tracking collar (Fig. 1) and a hand-held, mobile base station (Fig. 2). The tracking collar collects and stores GPS-fix information including collar location (latitude and longitude), date and time (Greenwich mean), and parameters indicating fix quality (e.g., dilution of precision and number satellites used) on a removable memory card (CompactFlash) contained within the collar. Raw satellite data (e.g., carrier phase, pseudorange, and Doppler measurements)

RESULTS AND DISCUSSION

The Clark GPS Animal Tracking System includes GPS-based tracking collars and a hand-held, mobile base station. Major components of the tracking collars include a single-board computer with a memory-card slot (CompactFlash), a 16-channel GPS receiver, and a spread-spectrum radio transceiver. All these components are mounted and electrically connected on a single PCB. These collar electronics are then contained within a watertight housing, which is mounted on a collar that can be sized for

MANAGEMENT IMPLICATIONS

The objective of this research to develop a GPS-based animal tracking system (Clark ATS), costing less than $1 000 per unit, with spread-spectrum radio frequency communication between collar and base station, real-time collar tracking capabilities, large (up to 8 GB) user-expandable on-board data storage, and very low power demand (mean consumption < 100 mW) and with very high battery capacity (19 AH D-cells) was successfully met. These attributes and capabilities of the Clark ATS should allow

ACKNOWLEDGMENTS

The authors wish to thank S. Hardegree and several anonymous reviewers for their critical review and comments on drafts of this manuscript.

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This research was funded by the US Department of Agriculture–Agricultural Research Service.

Mention of manufacturer, trademark name, or proprietary product does not constitute endorsement by the US Department of Agriculture, Oregon State University, or Boise State University and does not imply their approval to the exclusion of other products that may also be suitable.

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Technical NoteAn Advanced, Low-Cost, GPS-Based Animal Tracking System

Abstract

Resumen

Section snippets

INTRODUCTION

Clark GPS Animal Tracking System

RESULTS AND DISCUSSION

MANAGEMENT IMPLICATIONS

ACKNOWLEDGMENTS

Performance and accuracy evaluation of small satellite transmitters

Journal of Wildlife Management

A radio-tracking system for wild animals

Journal of Wildlife Management

A method for measuring the heart rate and stroke/pulse pressures of birds in normal flight. Arbok Universitet Bergen,

Matematisk Naturvitenskapelig

Satellite telemetry: a new tool for wildlife research and management

Wildlife radio tagging: Equipment, field technique and data analysis

Design of a miniature radio transmitter for use in animal studies

Journal of Wildlife Management

Early summer activities of porcupines as determined by radio-positioning techniques

Journal of Wildlife Management

Technical Note
An Advanced, Low-Cost, GPS-Based Animal Tracking System