BIOL 2050 Data Set 2 Pan Traps

Meta Data
Colour: The
colour of the plastic bowl used for one single pan trap set on the ground in a
line one meter away from the other colour bowls. The pan traps were set in an
alternating pattern: yellow, light blue, dark blue, white. The colour of the
pan trap was judged by the naked eye in comparison to one another.

 Site: The
specific habitat type to which the pan traps were placed. The pan traps were
set either deep in Danby Woodlot represented by “woodlot” or in a grassland
area beside the woodlot represented by “grassland”.  Locations were determined by sight of trees;
wooded area with many trees, leaves and twigs was considered woodlot whereas the
more open field with tall plants was considered grassland.

Abundance: The
total number of individual insects visible in the soapy water of one single pan
trap one hour after it had been set. Insects were counted by sight. Any species
with recognizable morphology of insects were considered. Any individuals not in
the soapy water were excluded from the count. Pan traps used were of identical
size and contained relatively equal volumes of soapy water.

Different
RTU’s: The number of different recognizable taxonomic units per pan trap. Any
insect with clear morphological characteristics unique to other insects in the
pan trap were considered an individual taxonomic unit. The taxonomic units were
counted by sight. Any insects not in the soapy water were excluded from the
count. Pan traps used were of identical size and contained relatively equal volumes
of soapy water.

 Data was collected
in the Danby Woodlot and Danby Grassland found outside of York University
campus on a Wednesday of September around 4:15pm. Skies were moderately clear
with temperate winds and a temperature of 18oC. The woodlot
consisted of a very shaded area containing many trees and vegetation. Twigs,
leaves, branches and human litter covered the ground. The grassland consisted
of an open area with many tall plants and flowers reaching heights of approximately
1m. A dispersed crowd of 18 York University students and one TA were walking
within both habitat types collecting different samples.  

 Hypothesis
It is
hypothesized that both colour and location of the pan trap will affect the
number and variety of insects found in a given area since different types of
insects may prefer a specific habitat or colour over another.
Prediction
It is
predicted that the yellow and white pan traps will contain a higher abundance
and variety of insects than the other colours because they resemble common
flower colours which will attract more insects of different taxonomic units.

It is
predicted that the woodlot will have a higher abundance of insects with a
variety of taxonomic units because the numerous trees in the area provide both
nutrients and shelter to many insects of different types. 
Material and Methods
A 10m strip of land was randomly chosen for testing in both the Danby Woodlot and Danby Grassland at York University. A transect was randomly placed at both habitat types and pulled in a straight line until the transect read 10m. Nine coloured plastic solo bowls were positioned at every meter of the transect.  The pan traps laid 1m a part in a line of nine in each testing site; making 18 pan traps in total. The bowls were strategically placed in both the woodlot and grassland with an alternating pattern of yellow, light blue, dark blue, and white. Each bowl was filled approximately half way with soapy water and left untouched for 1.5 hours. 
After 1.5 hours each pan trap was individually observed. The total number of insects found in the soapy water of each bowl was counted by sight and recorded. The same abundance of insects was then examined for recognizable taxonomic units. Any insect with morphological characteristics unique to the other insects in the bowl was considered its own taxonomic unit. The number of different taxonomic units was recorded for each pan trap. After each trap was examined the soapy water was discarded onto the ground and the living insects were released back into the environment.