After the previous outing I decided to no longer spend any time sampling the back 15 acres of my property. This is because it is a heavily dense forest, therefore the crown cover is much to dense and cannot support the growing of Giant Hogweed as it is shade intolerant. That was the difficulty I found in my previous outings, too much time spent in the higher elevation and dense forest plots that would throw the results off of the findings. It is evident that they grow in disturbed sites and with lots of sun.
In the bottom portion of the property (disturbed site) I continued to use the random sampling method, as well as built a 1 m2 quadrant . Using a larger quadrant is appropriate for this study as the plants are much larger, so having a larger sampling plot will give a better representation of the 15 acre disturbed site. At each site I take 3 sample plots 5m apart in a random direction. This allows for more area being sampled.
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Blog Post #5 – Design Reflections
This weekend I returned to my study sight to test out the data collection method I’d designed (outlined in Blog Post #3). Saturday was a bust due to poor weather conditions, but Sunday afternoon looked a lot better. I brought along the data collection tables I’d designed with the plan of collecting data on 3 individuals from each of my 4 species (Cormorant, Canada Goose, Franklin’s Gull and Mallard) for a total of 12 birds. For each bird, I recorded their behavior at 15 second intervals for a total of 5 minutes, noting the location of each behavior along my gradient (Shore→ Shallows → open water).
Replicate: individual birds
Response variables: behaviors (categorical)
Predictor variables: species (categorical), time of day (categorical: AM/Midday/PM), point on gradient (categorical)
A few limitations and problems I noticed when I got to my site and started collecting data:
- I hadn’t planned HOW I was going to select individuals to study in order to avoid bias. Naturally, I was drawn to the most active birds who would be interesting to watch for 5 minute intervals. I was also drawn to the birds closets to my location on the pond.
- I realized that my lofty goal of trying to record the behaviours of multiple individuals from 4 different species over 3 different daily time periods might have been a bit over-enthusiastic for this project. The Franklin’s Gulls, for example, DO NOT HOLD STILL! This species was frequently in flight, touching down for only brief periods. The range of their flight paths made it impossible to ensure I was watching the same individual over the course of 5 minutes.
- I realized that the pond is actually quite a bit bigger than I realized when I needed to identify a Mallard from other similar looking duck species from a distance.
- My observations led me on a full loop around the pond, stopping to collect data when I saw birds of interest. Again, this isn’t a very standardized procedure and could lead to bias when large groups catch my eye.
- 3x 5 minutes of behaviour observation is not a very significant period of time over the course of a 24 hour day. Will this be truly reflective of behaviour patterns?
- The larger birds (Cormorants, Canada Goose) seemed to each have claimed specific territory around the pond. There were no observation sites that allowed me to view both species at the same time.
Reflecting on my trial run this weekend, I’ve come up with a few modifications to my research project:
- I plan to keep using the data tables I created as I found them easy to use and well laid out for the data I was collecting.
- I’m going to narrow my focus from 4 species to 1, the Mallard. This species was found at many locations around the pond, and at all points along my gradient. They were present in the highest numbers as well, giving me plenty of subjects to sample from.
- I’m going to use a randomized number generator (ie: 1-10) to select my subjects: I’ll count to the random number, starting from left to right across the pond, and collect data on that individual. This should eliminate bias in choosing subjects.
- I’m going to select one observation point to work from, in order to prevent bias from wandering around looking for birds.
- Now that I’m going to be observing 1 species instead of 4, I will increase my number of subjects sampled each visit from 3 to 5, and increase my observation time for each individual from 5 minutes to 10 minutes. Doubling my observation time should provide slightly better behavior data.
- I’ve ordered a pair of binoculars off Amazon Prime, they’ll be here Wednesday! This should help me identify Mallards from other similar looking ducks and allow me to record data across the pond from a fixed location.
Based on these modifications, my hypothesis requires some adjustment as well. I will keep the hypothesis that the water bird species studied will display increased levels of higher-energy activities (flight, feeding, etc) in dusk/dawn periods due to cooler temperatures, and increased display of lower energy activities (comfort, resting) mid-day when temperatures are higher.
Again, the null hypothesis would be that time of day has no effect on the time-activity budgets of water bird species.
Based on my research on Mallards thus far, I also suspect that typical behavior patterns will vary across my gradient, with resting/comfort behaviours being observed on land, feeding in the shallows, and locomotion/alert behavior taking place in open water. Mallards are considered “dabbling” ducks and feed by grazing on underwater plants indicating that I predict that I will see these behaviours most often in the portion of the gradient I have designated at “Shallows” (< 5 m from shore or visible plant matter appearing on/near the surface)
Blog Post 4: Sampling Strategies
The three sampling strategies used in the virtual forest were haphazard, random, and systematic. Haphazard was the fastest of the three methods (estimated time of 5 hours and 17 minutes), random being moderate in terms of time (estimated 5 hours and 44 minutes), and systematic being the slowest of the methods (estimated 14 hours and 33 minutes). It is safe to assume that haphazard sampling has the fastest sampling time due the limited travel between sample points.
The two most common species in my sampling scenario where the Red Maple and the Chestnut Oak. These two species accuracy (in terms of percent error) were greater than the species that were less commonly sampled.
While doing trying multiple sampling techniques, it was relevant that the use of random sampling posed the least amount of percent error, and this could be do to the fact that there is very little/no overlapping in the sampling plots.
Blog Post 4
The different sampling techniques did not have very much variation for me. The most common species was Red Maple and the rarest was Sweet Birch. The sampling error was similar in all three techniques but the time it took to do a random sampling was the shortest at 5.5 hours. The accuracy did however change with the abundance of each species, the more abundant the less accurate.
Blog Post 3: Ongoing Field Observations
Prior to heading into the field on May 26, 2019 I came up with a rough plan of action. I decided to split my 2 15 acre sections into 3 plots per 15 acres. All plots being roughly 5 acres apart. I randomly selected a number (5 meters) as a radius to survey per plot. This allows for a very wide span of the 30 acre property. I have attached photos of my three pages of field notes, and a few photos of some of the plots found. Based on my little research on the Giant Hogweed before my field work I would hypothesize that I will only find them in the bottom 15 acres of my property, as it is a ‘disturbed’ site, where as the back 15 acres are a higher elevation as well as it is heavily forested. It is very possible that my hypothesis could be wrong, as the seeds of the Giant Hogweed can travel hundreds of meters, and with enough light could potential begin to grow in the forest.
Blog Post 2: Sources of Scientific Information
To obtain information on the Giant Hogweed I was required to do some research. I will be reviewing information on Giant Hogweed in Canada as an invasive species. This information came from ‘The Biology of Invasive Alien Plants in Canada. 4. Heracleum mantegazzianum,” Sommier and Levier. It reviews on how it takes over including its effects on the environment and human health. It also speaks on the identification and nature of the plant, as well as give possible management options, etc.
This is an academic, peer-reviewed material. https://www.nrcresearchpress.com/doi/pdf/10.4141/P05-158
In the last 3 pages of their review is a long list of sources sited in the text. They do not run their own tests, but rather review many others.
Blog Post 1: Observations
I have decided to my project on my own private property, located in Southbank, British Columbia, Canada. Southbank is a small remote rural area, about 24 km from Burns Lake, BC. There you will reach the ferry terminal of the Francois Forester that crosses Francois Lake to Southbank. Francois Lake is the 2nd largest natural lake in British Columbia. Our property is on the first street bordering the lake (we are on the upper side of the street, so our land does not sit directly on the lake shore). For the purpose of this study I have split the 30 acres into 2 separate sections to study and observe.To make things simple, I divided the property in half. The first 15 acres (Section 1) is the home front. It is mostly grass land and was select logged around 10 years ago. To break down section 1 there is around 1 acre of mature birch and aspen stand, 3 acres cleared (home, yard, etc.), 5 acres new immature growth (aspen, birch, cottonwood), and the remaining 6 acres is grassland. The second section is a mature mixed forest stand (birch, pine, spruce). 1/4 of the back property is made up of a steep gully. The entire property is on around a 30% slope. The first site visit was May 25, 2019, spring/summer time. The temperature was around 20 degrees Celsius, at 1015. It was sunny with a slight breeze. I began to notice the abundance of young Giant Hogweed (Heracleum mantegazzianum). Giant Hogweed (also known as cow parsnip), is a prennial plant and often grows around roadsides, ditches, and streams. It is an invasive plant and is know to commonly invade old fields and native habitats (woodlots). Their seeds remain viable in the soil for 15 years and each plant can produce up to 120000 winged seeds, which helps them travel long distances in the wind and streams. Once I obtained this information I began to thing of 1.) How does Giant Hogweed impact the environment (Natural Resource Impacts)? 2.) Pre-Cautions? How does it affect human health? and 3.) How do we prevent further growth as well as safe removal and management?
Below are photos of the site, both section 1 and 2.
References: http://www.invadingspecies.com/giant-hogweed/
Post 6: Data Collection: Cates Park
The first collection of viable field data was collected on Sunday May 19 at Cates Park in North Vancouver. Separating the park between east and west, north (inland) and south (next to shore), I have four areas to collect data to ensure independence and to account for variables (see Image 1). I sampled 20 replicates of 80 that I plan to sample, and noted the presence of absence of common species. Ten replicates were west and close to shore, ten were west and inland. These were nurse logs, and I will repeat this in the two eastern sections of the park as my data collection continues, and with forest plots of the same size as the circumference of the nurse logs in all four defined regions.
I have revised my experimental design and sampling strategies from previously posted attempts, as initial data collected was solely distance-based counts of conifers from the centre of nurse logs, and this seemed an inadequate representation of the species that grow within nurse logs. The difficulties I now face include sampling randomly selected forest plots, as they may contain dense growth and be more inaccessible.
Patterns observed include differences in mosses, lichens and berry species between the regions close to shore and further inland. However, Western Hemlock, or Tsuga heterophylla, has been the most frequent conifer studied within nurse log units, regardless of the distance from shore. These patterns continue to support my hypothesis, however studying forest plots that are not nurse logs will aid in determining how common Tsuga heterophylla are versus other conifers in the region, and will aid to prove or falsify my hypothesis.
Blog Post 6: Data Collection
I sampled 5 replicates during my initial round of field sampling. I didn’t have much trouble implementing my sampling procedure. I did lots of prep in the office before going out to site which made the field work efficient. The only difficult thing was travel in between sites. There was still snow on the ground so I used skis for most of the travel. Some sites did not have enough snow for ski travel (the more south facing slopes) so I was taking off and putting on skis during sampling. The partial snow cover added an additional slipping/falling hazard while sampling on some of the steeper sites.
While sampling I noticed that the different tree species seem to be growing in clusters. For instance, if my sampling site is in predominately birch stand, that may not reflect the stand characteristics 200m away. Additional sampling will help to get a more accurate measurement of the composition of the forest. I plan on sampling another 5 replicates soon and the snow is gone now so sampling should be easier.
Post Five: Design Reflections: Cates Park
My sampling strategy had a few difficulties, and therefore I decided to attempt another, hoping to redeem my first effort.
The first sampling strategy used a transect with alternating quadrats. Using my roommate’s measuring tape was the first challenge, since it only had imperial measurements, so I had to convert data into centimetres. I’m grateful I had a willing assistant who could help lay the measuring tape along the necessary gradients. The data collected was surprising as it revealed low numbers, and I realized that my next similar attempt should be on a more grand scale. I will need to be creative with data collection along points that are steep or heavily forested. One other difficulty was creating a data sheet template that would work for my purposes. I improvised and moved the data to a new spreadsheet that was more organized.
The second set of data collected was haphazard and distance based, and I believe, more successful. Five trees were selected haphazardly for ease of access in this forested region. These were the centre point where I measured neighbouring species. Again, the tape measure was not an ideal tool, and I benefited from having someone to assist. After the data collection, I realized I should have created a map, image or layout of where each tree was situated in relation to the midpoint. This data was predicted but I’m looking forward to more sampling.
I will likely continue to collect data with the second approach, and add another kind of sampling strategy to assist in the bigger picture of my hypothesis. By adding varied sampling techniques, replicates and variables, I will likely be able to prove or disprove my prediction and hypothesis. Modifications to data collection will also include appropriate measuring techniques and recruiting more volunteers!
