Wildlife Management Exam 3 - Labs

Radio telemetry + fisher HSI

What are the names of two radio telemetry techniques that we used?

• Traingulation: taking bearing from 3 locations, finding the intersects. The middle triangle is where the individuals should be located.

• Homing: following the signal to the source of it.

What are the three primary pieces of equipment that are required for conducting radio telemetry?

• transmitter (attached to the animal)

• receiver (to detect the signal)

• antenna (connects to the receiver to pick up the signal)

What is a null point?

direction where the antenna is not able to detect the signal on the transmitter

What setting on radio telemetry equipment can be adjusted to narrow the distance between null points? Why is lowering the null points beneficial?

Lower gain sound. This allows you to be more accurate in locating the animal.

What is the process for orienting a map and projecting compass bearings?

Line the arrow on the compass with north, put it on a north line on the map, rotate the map until the red north is in the shed. Now you can remove the compass from the map.

What is the name of the area that you create after projecting your 3 compass bearings for the direction of a tagged pheasant onto the map during lab?

triangle of uncertainty

What model did we use to determine fisher presence?

Fisher Habitat Suitability Index (HSI), developed by Allen (1983)

What are the 4 variables we measured on the Fisher Habitat Suitability Index?

• % tree canopy closure

• average DBH of overstory trees

• tree canopy diversity (levels of canopy)

• % overstory comprised of deciduous trees

How to calculate percent canopy closure?

(average x 1.04) - 100

How to calculate percent canopy that is deciduous?

(deciduous % / total %) x 100

What is the calculation for Fisher Habitat Suitability Index?

HSI = (V1 x V2 x V3)^1/3 x v4

What is the tool that we used to calculate tree canopy closure?

spherical densimeter

What versions of central tendency did we calculate for each variable of the HSI index?

• % canopy closures (both) = mean

• DBH (in) = mean

• canopy diversity (levels) = mode **most commonly occurring #

What was our fisher habitat suitability index findings?

Not suitable habitat as there was too much overstory canopy comprised of deciduous trees.

What type of habitat do fishers prefer?

• 10-50% deciduous overstory canopy (dont love too mcuh deciduous overstory)

• 75-100% tree canopy closure (like canopy closure, just not deciduous)

• 15-20in DBH (bigger trees)

• 3 canopy diversity (lik levels)

What are two other variables that we need to consider when analyzing if habitat is suitable for fishers?

• availability of reproductive sites (den in high hollows within trees)

• prey presense (snowshoe hare, mice, voles, shrews, etc.

What is a short coming of Allen (1983) and similar habitat suitability index models from that era? Describe why you think this could be problematic.

our environment has shifted since this model was made. Fishers may now be more open to living in areas with higher deciduos canopy cover or less canopy diversity due to recent urbanization causing them to settle in other previous less suitable habitats.