Biotelemetry and Biologging Flashcards
Active Transmitters
Electronic tags that have their own energy source.
(Adams et al, 2012)
What are the similarities and differences between biotelemetry and biologging?
Both techniques involve remotely monitoring behavioural, physical, or environmental information, but in biotelemetry a signal from a transmitter carried by the animal sends the information to a receiver whereas in biologging the information is recorded and stored in an animal-borne device and the information is downloaded after the logger is recovered.
(Cooke et al, 2012)
What are the disadvantages of biotelemetry and biologging?
Costly
Obtaining an adequate sample size of independent data for strong statistical power and to make population level inferences can be difficult on a limited budget.
Large dataset can be difficult and take a long time to interpret.
Special skills needed.
(Cooke et al, 2012)
What is biotelemetry data used for?
This location information provides insight into migration, habitat use, behaviour, productivity, and survival.
(Adams et al, 2012)
What are two basic categories of biotelemetry?
Acoustic or radio.
(Adams et al, 2012)
What are the advantages of biotelemetry and biologging?
- The ability to ID individual animals.
- The ability to locate individual animals without having to observe or recapture them.
- A variety of detailed information can be collected over time (e.g., location, depth, activity, environmental parameters) without the need to recapture or directly observe the animal.
- Allows the collection of data in harsh/inaccessible conditions.
- Good for studying endangered animals because they are relatively noninvasive, are data rich for small sample sizes, and do not require the permanent removal of animal from their natural environment.
- Allows us to couple behaviour with other variables such as physiology.
- Provides realism not possible in lab.
(Adams et al, 2012; Cooke et al, 2012)
What types of studies can be performed using telemetry? Provide an example and benefit of each.
Descriptive
- Determine unknown life history aspects.
- e.g., movements or spawning times and locations.
Correlative
- Relationships between measured variables.
- e.g., temperature and residency
Manipulative
- Can provide evidence to support or reject a hypothesis.
- e.g., controlling temperature to see impacts on animal.
(Adams et al, 2012)
Compare and contrast the benefits of using acoustic/radio telemetry to the other.
Radio usually used in FW because of advantages in antenna size and reception.
Acoustic used in SW because of higher water conductivity.
Radio tags can be tracked from greater distances by a range of methods (e.g., land, boat, air) whereas submerged hydrophones are needed for acoustic tags which limit reception range when tracking by boat or fixed data logger stations.
Acoustic is excellent for deep water and radio isn’t.
Radio is better for turbid water as well as water that is heavily vegetated, has algae, or is turbulent.
Acoustic you can get actual positions, radio is just general.
(Adams et al, 2012)
Location Error
The linear distance between the actual and estimated location.
(Adams et al, 2012)
What are common errors with telemetry?
Location error, false positives, and false negatives.
(Adams et al, 2012)
What trade-offs (advantages/disadvantages) need to be considered when selecting radio and acoustic transmitters (tags)?
Longer operating life of tag:
A - can have a longer-term study
D - tag will be bigger and heavier
Higher range of tag:
A - bigger signal range and study scale as well as higher likelihood of detecting the animal
D - tag will be bigger and heavier
Smaller tag size:
A - can study smaller fish as well as those at earlier life stages
D - tag won’t last as long or have as far a range
Tag with internal antenna (radio):
A - less impact from tag on fish and easier operation
D - reduced range and tag will be bigger and heavier
Tags that have sensors to take different measurements (e.g., temperature):
A - will gather more information including both positioning and environmental data
D - tag will be bigger and heavier
Tags with activity/mortality circuit:
A - useful for monitoring life of fish
D - tag will be bigger and heavier
(Adams et al, 2012)
What is an assumption of almost all telemetry studies?
Aka what is the fundamental principle of all telemetry studies.
The tagged animals are representative of the untagged population, i.e., that the processes by which study animals are captured, handled, and tagged, as well as the act of carrying a transmitter, will have minimal effect on their behaviour and performance.
(Adams et al, 2012)
How can tagging fish impact them?
Direct physical impacts: elevated stress levels, injury, death.
Interrupted integrity of scales, mucus, or skin can increase infection risk.
Altered buoyancy compensation ability.
Reduced swimming performance.
Reduced feeding.
Changes in dominance status.
Changes in above behaviours can impact growth, rate of maturation or migration, or increase vulnerability to predation.
(Adams et al, 2012)
Tag Burden
Transmitter to body-weight ratio.
(Adams et al, 2012)
What tag burden is most commonly accepted?
The transmitter in air should not exceed 2% of fish body weight in air.
(Adams et al, 2012)
Tagger Effects
Different outcomes that are the result of different taggers being used in a study.
(Adams et al, 2012)
What are the 3 most common methods for transmitter attachment?
External attachment, gastric implantation, and surgical implantation.
(Adams et al, 2012)
What are the advantages and disadvantages of external transmitter attachment?
A’s
Executed quickly, light or no anesthesia, no attenuation of signal by fish body wall or internal organs, can be retrieved without recapture (e.g., pop-up tags), and external sensors accommodated.
D’s
Risk of fouling, entanglement or transmitter loss, source of drag/swimming affected, irritation/infection at attachment site, balance affected if asymmetric, not ok for growing fish.
(Adams et al, 2012)
What are the advantages and disadvantages of gastric implantation of transmitters?
A’s
Executed quickly, light or no anesthesia, position at centre of balance, low risk of entanglement/drag, low risk of infection, some sensors accommodated.
D’s
Interference with cessation of feeding, cough response, rupture of stomach, regurgitation or egestion of transmitter, irritation at attachment/exit site.
(Adams et al, 2012)
What are the advantages and disadvantages of surgical implantation of transmitters?
A’s
Position at centre of balance, no entanglement or drag, internal sensors accommodated, allows long-term monitoring.
D’s
Relatively slower procedure, biologically invasive, deep anesthesia, required a skilled surgeon/tagger, risk of active/passive expulsion, risk of infection, irritation at radio antenna exit site (when used).
(Adams et al, 2012)
