Utilizing Different Coloured Pan Traps to Sample Insect Abundance and Number of Different RTUs in Grassland and Woodlot Areas near/in Danby’s Woodlot at York University

The purpose of this observational study was to test whether certain pan colour(s) attract more insects, i.e., based on the abundance of insects that land per coloured pan (white, blue, or yellow), or attract more of a certain species of insects, i.e., based on the number of different recognizable taxonomic units (RTUs) observed per coloured pan, than other coloured pan(s) in respective areas of grassland or woodlot. The pans were filled with ~10-15 mL soapy water ¼ of the bowl, which attracted and killed the insects that landed in it. The study was conducted in both the grassland and woodlot areas near/in Danby’s Woodlot at York University on October 1, 2015 beginning at 3:00 pm and ultimately ending at 4:20 pm by group members Gajamugan Rajavarothayan, Gopaul Parbatie, Albert Lin, and Hannan Fayyaz. Using a transect tape laid down on the ground, each coloured pan was placed in a straight line with a 1 meter separation between them in a random area in either the grassland area (covering a span of ~9 m in length in the straight line by using 9 pans here) or woodlot area (covering a span of ~8 m in length in the straight line by using 8 pans here, due to the T.A. miscalculating the number of pans). Each pan was placed in alternating colours in both locations so as to keep the colour of the pan's effect in attracting insects balanced and in the event a certain colour attracts a particular species or amount of insects more so than others, this arrangement of pans will reveal that effect, should there be one. Sample size, n = 9 pans sampled for the grassland location and n = 8 pans sampled for the woodlot location. The abundance of insects within each pan was observed visually and counted while the insects were dead in the soapy water solution in the pan to test whether certain pan colour(s) attract more insects than other coloured pan(s) in their respective locations (grassland or woodlot). The number of different recognizable taxonomic units (RTUs) within each pan was observed visually and counted while the insects were dead in the soapy water solution in the pan to test whether certain pan colour(s) attract more of a certain species of insects than other coloured pan(s) in their respective locations (grassland or woodlot). An insect guide was also consulted to aid in the process of discriminating the number of different RTUs present per coloured pan. The pans that were placed in the grassland area were in an area fully exposed to the sun and none were in the shade; the grassland vegetation in the areas we placed the pans was below 0.5 m, i.e., below knee level, and had some moisture in its soil but in neighboring grassland areas to our area (of which we did not put any pans but is being described to depict the details of the location overall) contained other plant species and its grassland vegetation height increased to around 1-1.5 m, i.e., above knee level. Insects like lady bugs, bees, and flies flew around the grassland, while some flies and birds flew in the woodlot area. The pans that were placed in the woodlot area were in a shaded area as all the trees prevented direct sunlight from reaching the pans but the area overall was still somewhat light up as it was during the day where we conducted this observational study. The woodlot contained more soil, which had some moisture, and few plant species on the ground. The grassland pans were placed from 3:00 pm to 3:07 pm and we then observed the abundance of insects and number of different RTUs per pan in the grassland from 4:00 pm to 4:10 pm, i.e., ~1 hour after the pans were initially placed in the grassland so this is how long the insects had to reach the bowl. The woodlot pans were placed from 3:10 pm to 3:15 pm and we then observed the abundance of insects and number of different RTUs per pan in the woodlot from 4:10 pm to 4:20 pm, i.e., ~1 hour after the pans were initially placed in the woodlot so this is how long the insects had to reach the bowl. At both locations, the grassland and woodlot, the atmosphere temperature was 15 degrees Celsius, the weather was sunny with a few clouds, wind speed was 19 km/h blowing from the North-East, humidity level was 32%, pressure level was 102.8 kPa, and visibility was 16 km. Hence, overall these factors provided adequate conditions for viewing the insects within each pan and recording data from it.