Category: Post 3: Ongoing Field Observations

The organism that I plan to study is the bullfrog (Lithobates catesbeianus) present at the Champlain Lake south wetland/swamp site chosen for observation. I had taken note that the stationary presence of a Lithobates catesbeianus in stagnant water appeared to be dependent on its location featuring sub-merged aquatic vegetation. None of the seven total observed Lithobates catesbeianus were present in an area of water that had no aquatic vegetation beneath the organism.

The three locations I have chosen to observe the organism of interest is the interior small channel flowing south, the main open body, and the lake mouth channel running into the wetland body (see photo for location references).

1. Location 1: Interior small channel (south flowing)
   The water in the wetland had dropped approximately 1 foot, leaving the channel to be very shallow and featured minimal room for aquatic vegetation. The channel was very stagnant and I did not observe any bullfrogs (Lithobates catebeianus) present in this area. I assume their absence in this channel was due to low water levels causing restriction for travel along the channel.
2. Location 2: Main Open Body
   The main open body of the wetland also had signs of lower water levels along the shoreline, exposing previously submerged rocks and some dried up aquatic vegetation. This location had the majority of Lithobates catebeianus present and featured ample aquatic vegetation beneath each organism. I noted in my field journal the surrounding areas lacking visible aquatic vegetation, also lacked the presence of a Lithobates catebeianus. The water was very stagnant in this location as well.
3. Location 3: Lake Mouth Channel (running southbound into wetland body)
   The lake mouth channel had a few sections of submerged aquatic vegetation and featured one smaller Lithobates catebeianus on the interior side of the channel. This channel had slight/low flow entering southbound into the wetland body and I predict the lack of Lithobates catebeianus presence throughout the lake mouth channel location is due to minimal aquatic vegetation coverage and difference in water velocity.

I postulate that the presence of a stationary Lithobates catebeianus is dependent on ample (>50%) coverage of submerged aquatic vegetation beneath the organism. Based on the postulate hypothesis, one potential response variable could be the Lithobates catesbeianus and one potential explanatory variable being the percentage of submerged aquatic vegetation coverage. The response variable would be categorical in this case, being the presence/absence of the Lithobates catesbeianus, and the predictor variable would be continuous, being the percentage of aquatic vegetation coverage. I expect the Lithobates catebeianus is stationary in water with ample aquatic vegetation beneath the organism to evade other predators present in the wetland.

I had a few images to accompany this post, however, are too large to include.

 

I plan to study the tidal pools at McNeil Bay in Victoria BC. The organisms that live in these pools are both biotic and abiotic. Examples are barnacles, fish, brown and green algae. The abundance of these organisms varies depending on the zones of the pool from high tide to low tide. The three locations I chose to observe the changes in were low tide, intermediate tide and high tide. Below is some notes that I recorded on the locations:

1. Low tide: Greater biodiversity, the organisms here do not need to be well adapted to drying out and extreme temperatures. Organisms such as anemones, brown seaweed crabs and fish live here.
2. Intermediate tide: At this point there is a mixture of both species in the low and high tide but mostly it looks like there are a few invertebrates (chiton) but lots of seaweed.
3. High tide: Organism here have to survive drying out, currents and wave action. A larger abundance of barnacles, seaweed with only a few invertebrates can be observed.

These patterns could be due to the very different environments that they live in varying with elevation. I hypothesize that low tide zones will have greater abundance than high tide for (species) due to the less harsh conditions for it to live in. I predict larger biotic organisms are only in low tidal zones. Based on my hypothesis one potential response variable would be the total number of each species in the tidal pools which is categorical. A continuous variable would be the percentage of cover of each pool with seaweed. One explanatory (predictor) variable would be the unique environment the tide pool provides for the species. This variable would be categorical since there are 3 distinct locations of the pools.

I am not very good at drawing so I only sketched a few things but mostly I have chosen to take pictures and document my field observations all electronically.

 

1. Identify the organism or biological attribute that you plan to study.

After visiting my study site several times over the last week, I am eager to focus my research project on bird species in some way.  Over the last couple days, my ideas for study subjects have been wide ranging. Amongst some of my ideas:

• attempting to sample the abundance of all individual bird species I encounter  at various points in the park (an unrealistic idea for someone with little to no working knowledge of bird identification, especially by song)

• Measuring the abundance of bird species at different times of day, to see when activity is highest. (an appealing idea, but again with little knowledge of various bird species this study would likely have a large bias due to my own inaccuracies)

• I then thought about grouping birds into groups (ie: songbirds, water birds, birds of prey) and sampling throughout the park at various times of day.  (Better, as I’m confident I can accurately tell the difference between these 3 groups, however the studies I looked at still put considerable emphasis on using bird songs to count species that have low visibility.)

 

I finally decided that water bird observations would be the direction I took as there are fewer species and each is fairly easy to accurately identify, even for an inexperienced bird watcher like myself.  They are also highly visible given their propensity for water and shore-based activities, so the need to identify based on song is eliminated. I will focus my observations on the 2 ponds in the park as I have not observed water birds outside of the immediate area of the ponds.

I knew I wanted to look at behavior patterns throughout the course of the day to see if I could discern any differences.  Once I thought more about bird behavior, I realized I would need to find a way to quantify these activities in a way that I could then interpret as data.  My admittedly limited experience in ecology prior to this course led me on a clumsy search through the library resources where I eventually stumbled upon the term “Time-activity budgets”.  This describes perfectly what I was hoping to sample and I’ve found several good papers describing techniques that would be feasible for the scope of this project.

I finally settled on measuring the time-activity budgets of 4 common waterfowl species at 3 different times of day (dawn, midday, dusk)

• • • Mallard
    • Canada Goose
    • Franklins Gull
    • Spotted Sandpiper

Note: This species list is still subject to change as I had not taken note of specific species abundance of waterfowl during my previous visits. I plan to use the 4 most common species present in the park and will finalize my list during a trial data collection period this weekend!

1. Use your field journal to document observations of your organism or biological attribute along an environmental gradient. Choose at least three locations along the gradient and observe and record any changes in the distribution, abundance, or character of your object of study.
   • I’ve noticed that some species (ie: the Gulls) spend a lot of time on the shore while others (ie: Mallards and Canadian Geese) are often found swimming in the open water. Therefore, the gradient I am using in my observations:  Shoreline (land) → shallows (estimated < 5 m from shore or visible foliage above waterline) →  open water
   • Sample Times: Dawn/midday/Dusk
   • Using the “Rule of 10” suggestion from the tutorials, I plan to collect data at my site on 10 different days (10 replicates).
     • 10 days x 3 times of day = 30 total sample periods
   • I plan to sample 3 individuals from each species at each visit
     • 4 bird species x 3 individuals/species = 12 individual birds/period x 30 sample periods = 360 individual birds analyzed.
   • I will be recording bird activities in a categorical nature (ie: Feeding, Resting, Comfort care, Locomotion, etc) every 15 seconds for 5 minutes, for each subject analyzed.
     • 5 minutes/bird, recording behavior every 15 seconds = 20 data points/bird
     • Each sample period: record data for 1-3 members (depending on abundance, goal=3) of each target species = 4-12 birds x 5 minutes each = 20-60 minutes= 80-240 data points/sample period
     • 10 days of sampling at 3 periods/day = 30 total sample periods = 2400-7200 data points collected
2. Think about the underlying processes that may cause any patterns that you have observed. Postulate one hypothesis and make one formal prediction based on that hypothesis. Your hypothesis may include the environmental gradient; however, if you come up with a hypothesis that you want to pursue within one part of the gradient or one site, that is acceptable as well.

I predict 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.

The null hypothesis would be that time of day has no effect on the time-activity budgets of water bird species.

In studying 4 different species, I also hope to detect differences in activity patterns between them. I predict that the larger species (ie: Canada Geese) will spend more time feeding than their smaller comparators due to the increased energy demands required by larger organisms.

The null hypothesis here would be that the size of bird has no effect on behavior patterns throughout the day.

 

1. Based on your hypothesis and prediction, list one potential response variable and one potential explanatory variable and whether they would be categorical or continuous. Use the experimental design tutorial to help you with this.
   • Response variable: behavior patterns (categorical)
   • Explanatory variable: time of day (categorical)

Based on the tutorial on experimental design, my study would be classified as a tabular design.

 

 

Sample data collection table that I have designed and will test this weekend:

L=land S=Shallows O= Open water

 

I plan on studying the amount of paper birch in the area surrounding disturbance in my site. Disturbed areas consists of two large areas in which trees were removed in order to accommodate for housing to be developed. I plan on surveying along the edge of the disturbed area in 5m,10m and 20m intervals( this variable is classified as continuous )  . I predict that due to paper birch being a shade intolerant species it will only be found on the edge of the disturbed area due to the fact that without adequate sunlight it does not thrive. One potential explanatory variable that could affect the growth of paper birch in this area could be percipitation.