CAPITAL INVESTMENT

ERDC TN-DOER-E18

February 2005

CAPITAL INVESTMENT:

Research goals can best be achieved only after careful

consideration is given to study design. However, the initial investment in equipment is

frequently cited as a limiting factor when designing a study. Manual tracking may have the least

capital cost when compared to a fully automated tracking system; however, when factoring in the

cost of manpower for manual tracking, fully automated systems may actually be the better value.

The duration of the study is often a key factor in the optimal type of system deployed.

The minimal equipment necessary for manual tracking would be tags, a hydrophone, and a

receiver. Scanning receivers averaged $2000 to $3000 for those models reviewed. Omni-

directional and directional hydrophones typically average $350 and $600 per unit, respectively.

Major expenses are incurred in the purchase of radio and acoustic transmitters, whose cost

ranged from $150 to $300 each. Some manufacturers have combined radio and sonic transmitters

for as much as $450 per unit. These transmitters are typically not recovered and are considered

expendable.

For fully automated systems, scanning receivers with datalogging functions and the capability of

monitoring both acoustic and radio frequencies typically costs $8,000 each. Wireless hydro-

phones average from $4,500 to $5,000 per unit. Wired hydrophones generally cost less (<$750)

but will typically require more deployment time, especially if bottommoored. The decreased

cost of field personnel may offset the higher costs associated with the initial purchase of wireless

hydrophones. Transmitter prices varied based on operational life and other features. One

example is a coded acoustic transmitter (76.8 kHz) with an operational life of 92 days at a 5-second

burst rate that costs $275 per transmitter. Therefore based on tagging 100 fishes during an

andromous fish migration study, at $300 per tag, the transmitter investment alone would be

$30,000. Depending on the system (wired vs. wireless monitoring) costs associated with

additional hardware requirements can be substantial including wireless hydrophone antennas

($400 per unit); remote terminal control options ($921 each); ultrasonic up-converters ($902

each); directional baffles ($55 each); mounting brackets ($220 each); float assembly ($110 each);

marine batteries to power shore-based stations; and anchors, chain, stainless steel cable, and

other expendables.

CONCLUSION: As discussed above, there are obvious financial, design and logistical

considerations in telemetry research. A variety of instruments and techniques are available for

monitoring freshwater and marine fishes. Selecting the proper equipment and establishing clear

and concise research objectives are critical to the success of any monitoring effort. Consideration

must be given to the species to be studied, its environment, and the type of data needed to meet

research goals. This in turn will factor prominently in the type and size of transmitter selected

and subsequently in the type of receivers and hydrophones necessary, as well as the appropriate

deployment strategy. Flexibility of the system along with a capability to upgrade components to

accommodate multiple projects over a span of years should also be considered.

TELEMETRY EQUIPMENT SUPPLIERS: As an aid to the reader, web site addresses of

telemetry gear manufacturers mentioned in this technical note are given below. Although the list

is not exhaustive, it does reflect some of the leading companies in telemetry equipment

manufacturing including Advanced Telemetry Systems (www.atstrack.com); AVM Instrument