In my ongoing field research, I’ve chosen to study the distribution of the common raven (Corvus corax) along an elevation gradient in the Golden area. Ravens are fascinating birds known for their intelligence and adaptability, and I’m interested in understanding how their distribution varies with elevation.
Field Journal Observations:
- Downtown Golden (Kicking Horse Bridge Area):
- Date: March 25, 2024
- Time: 10:00 AM – 12:00 PM
- Weather: Clear skies, mild temperature
- Observations: In this urban setting, I observed a moderate presence of ravens. They were often seen perched on lamp posts and rooftops, as well as scavenging for food in open areas and along the riverbank.
- Golden Golf Club:
- Date: March 27, 2024
- Time: 8:00 AM – 10:00 AM
- Weather: Overcast, cool temperature
- Observations: At the golf club, which is situated at a slightly higher elevation compared to downtown, the presence of ravens was less frequent. However, I still observed a few individuals flying overhead and perching on trees near the golf course.
- Kicking Horse Mountain Resort Area:
- Date: March 30, 2024
- Time: 1:00 PM – 3:00 PM
- Weather: Sunny, warm temperature
- Observations: As I ascended to higher elevations at the mountain resort, the presence of ravens became scarce. Although I spotted one or two individuals soaring at higher altitudes, they were not as abundant as at lower elevations.
Underlying Processes and Hypothesis:
Based on these observations, I hypothesize that the distribution of common ravens is influenced by elevation, with higher elevations exhibiting lower raven abundance compared to lower elevations. One underlying process that may contribute to this pattern is the availability of food resources. Lower elevations, such as downtown areas, may provide more abundant food sources for ravens in the form of human waste and discarded food. Conversely, higher elevations may have fewer food resources available, leading to reduced raven abundance.
Prediction and Variables:
Hypothesis: The abundance of common ravens decreases with increasing elevation.
Prediction: As elevation increases, the number of common ravens observed will decrease.
Response Variable: Number of common ravens observed per hour of observation (continuous).
Explanatory Variable: Elevation (continuous).
By collecting data on raven abundance at different elevations, I aim to test this hypothesis and gain a better understanding of how environmental factors influence bird distribution in the Golden area.
Sounds like a great start to your study. Remember to consider what elevation you are starting at (i.e. already in the mountains) and how high up you are when you finish. Also, the ecosystems associated with those areas and how those change with elevation which will help you as you interpret your data. For instance, in Kamloops I tend to observe ravens at higher elevations in the city, but I have a different elevation gradient than you.
This is a super interesting topic! Given the information on your gradient, your hypothesis and variables make a lot of sense to me. I was wondering if you have considered the way human activity and urbanization may affect your results. It may be possible that the population is denser in certain areas due to food sources, nesting opportunities, or lack of competition. This may be an interesting confounding variable to consider when analyzing your results!