FOCUS• FOCUS

• FoCuS

• focus

Wildlife Radiotelemetry• Read Chapter 14 in your Book• Read the online report by Mech and Barber

(2002) as linked on the course web page

Wildlife Radiotelemetry

• We will discuss:– What is it?– Why is it used?– How is it done?– What are the problems?– How are these problems overcome?– What are the alternatives?– What are the advantages of each?– When is it a “good” technique?

• Read Chapter 14 in your Book• Read the online report by Mech and Barber

(2002) as linked on the course web page

Hands on!• We will gain experience with

– How the equipment works– Homing to a transmitter “contest #1”– Estimation of system error and bias

• Use of compass• Field experiment• Analysis

– Triangulation “contest 2”• Use of GPS• UTM coordinates• Use of maps• Plotting locations

• Demonstration of computer resources for plotting and analysis as time permits

What is radiotelemetry• Involves the attachment of a radio

device to a wild animal for the purpose of monitoring its location– May be attached externally or internally

• When is internal/external more appropriate?

– May be one of several types of devices:• Conventional VHF radio transmitter

– May have various optional features» Motion sensor» Mortality sensor» Heart rate monitor, temperature sensor,…» Remotely triggered syringe

Types of devices, continued

• Conventional Satellite Transmitters– Must pay for satellite use

• GPS receivers– On board data retrieval– Remote data retrieval

• Conventional radio• Satellite download

– Must pay for satellite use

• Acoustic and combo transmitters

• More details on each in readings–Will discuss as time permits

What questions are answered or hypotheses tested through wildlife

radiotelemetry?1 – 2 -3 -4 –

Questions and hypotheses• Dispersal: when, which individuals, how far• Migration: as above, and pathways• Other movements: as above, and rate• Location: dens, nests, habitat type• Behavior: avoid or attracted to others …• Space use: home range, territory, core area• Survival rate: requires lots of transmitters• Breeding: to locate nest, den, brood …• Impacts: of land use, management, …

Is radiotelemetry a “good” technique?

Is radiotelemetry a “good” technique?

• Be thinking about this as we go along over the next few weeks

• It is often the ONLY way to collect certain data– Are those data really needed?– Are there other ways to achieve the same

objective(s) that are “better?”

• What are the alternatives?– Other thechniques– Do not achieve the objective

Does the marked animal typify population?

• Minimizing the effects of radiomarking (13 ways)– Assume there IS an effect(s)– Literature review for proper attachment/effects– Consult the experts about similar species/studies– Use smallest radio possible– Use most inconspicuous package/attachment– Test the attachment method– Pilot study for first-time method or species– Practice attachment on animal or surrogate– Ensure fit of package on each individual– Consider periods of stress (weather, breeding,…)– Observe post-attachment behavior– Allow for post-attachment acclimation– Publish positive AND negative aspects of your

experience

Costs• Receivers cost between $500 and

$5000+– Vary from limited-frequency, “channel”

type to full frequency, digital type– May be radio, acoustic, or combo– May be able to transmit an injection or

download signal– May be able to receive other data

• GPS coordinated• Body temperature• Others

– Scanners or manual tuning

Cost, continued• Transmitters cost from $125 to $5000+

– Small VHF with no options are cheapest– Subminiature and Large units are more– Options cost!

• GPS is more

• Satellite rental– $100+ /mo/transmitter

• Depends on agency

• DYI is fun and cheap in the short run– More costly in the long run

• Time and reliability are the main concerns

Obtaining Equipment• Dozens of companies that specialize in

providing transmitters, receivers, and accessories– TWS working group maintains a web site

with info• See course page links

– Selection may be based on agency contract, country, familiarity, or track record

• Prices are similar– You don’t always get what you pay for

• See expert advice from multiple experts

Conventional Radiotelemetry

• VHF – UHF frequency is assigned by the FCC– EKU uses 150-152 MHz receivers

• Each transmitter (animal) usually has a unique frequency• Transmitters should be separated by 10 KHz or more to

distinguish between individulas– E.g., 150.500, 150.510, 150.520– Limited to about 200 animals in a study area– Need to avoid frequencies of other studies in your area!

• Transmitter sends out pulses or beeps– Slow pulse uses less battery but takes

longer to radiolocate– Manufacturer may alter pulse rate and

signal strength to reduce battery drainor increase performance

• Depends on your objectives

Directional Antenna• A directional antenna is used, much like

the old rooftop TV antennas on a rotor– You get the strongest signal when the

antenna points at the transmitter• I.e., the loudest beep• The animal is that way, but how far?• You must “home” or triangulate• to find a location

• Directional antennas may be Yagi, dual yagi, or loop antennas– We will use 2-element (H-antenna) or 3-

element yagi-type