individuals/area sampledMost sophisticated population estimate
Number of individuals
UnitlessMust be comparede.g. fatty acid scent tab coyote tracking
Lease sophisticated population estimate
Catch effort: CE (%) = A * 100 / [T-(S/2)]
A= abundanceT= trap nightsS= sprungEvery time you check a trap, you have a __% chance of catching an animal
UTM: C = sqrt abs value (y1-y2) + (x1-x2)
Universal Transverse MercatorActual x1 y1Estimated x2 y2
How to improve telemetry accuracy
1. More points2. Get closer3. Work faster4. Better angles (90-120)
# plots with species / total # plots
# / # trees
What is the average volume of a log?
(length) (pi) [(diameter/2)^2]
How open is the canopy?
Group average / number of plots
Use out of proportion to availability
% plot covered
% twigs browsed
How do we know what an animal likes to eat?
Stomach analysisObservationProvide foodBrowse survey
Who cares what an animals likes to eat?
Hunters (candy food - e.g. corn --> waterfowl --> not nutritious)Health of population (eating selected vs avoided foods)Landscaping (e.g. airports, roadsides)HabitatWinter deer ecology (cover, insulation, snow build up)
Available < useCake
Available = usemeh salad
Available > usepickles
Add y values up to inflection point (+0)
Shannon-Wiener Diversity Index: H' = -sum [pi * ln pi]
H' = information indexpi = # individuals / totalCompare to diversity index
J = H' / ln R
J = evenness indexR= # of species1 = perfectly even
Population Estimate Assumptions
Population is closedEqual probability of captureMarks do not affect mortalityMarks are retained and recognized
Vegetation Sampling Techniques
Fixed areaLine interceptPoint centered
What is the difference between active and passive calling surveys?
Active: howl surveyPassive: songbird point counts
Does distance sampling underestimate or overestimate the population size?
Underestimate, because you don't hear every bird that calls, and some birds might not be calling if you're there
1 trap checked 1 time
How to fix a Sherman trap
If it goes off too easily, pull the notch closer to you and vise versa