Distance Sampling for Abundance and Distribution of Mobile Species - Sweep net dataset 4

The following data set was collected in the Danby Grasslot area at York University on September 29th, 2015 at approximately 3:30 to 4:30 PM. Sampling conditions included cloudy weather, rain and a temperature of 18°C. My group members, Amanda, Phenil, Tonia, and I were assigned four different sets of data to obtain. I was assigned to obtain the sweep net dataset with my partner Tonia. Tonia and I then headed to the Danby Grasslot area and began to collect such data. A transect measuring tape was unwound and extended twenty meters long. The transect was then placed on the floor, in a straight line, at a random location in the Grasslot area. The twenty-meter straight line was walked over a time interval of two minutes; the equivalent of walking ten meters a minute or fifteen centimeters a second. A net was used to continuously sweep the plants and grass that were located along the transect line during the walk. At the end of the sweep walk, the number of insects found within the net was counted and recorded. Among those insects present within the net, the number of different recognizable taxonomic units, RTU’s, was also recorded. RTU’s were used in this experiment to distinguish between the different types of insects that were found within the net. Insects that contained similar features were grouped together and given a general group name, the number of different groups present within the net was recorded. Such group names included flies, spiders, ladybugs, beetles and snails. The transect was then picked up, moved to another random location and the process was repeated for another nine trials. On the field, this distance sampling method allows BIOL2050 students to estimate the abundance and distribution of a mobile species population over a large surface area in a relatively short time period. Off the field, this laboratory gives students the opportunity to better describe their metadata as well as share their data findings with the greater scientific world.