I took a Wetlands Ecology course during my graduate studies at the University of Wisconsin-Madison and one of our semester-long projects was to visit the same wetland at least once a week and record observations. We could do this by drawing pictures, taking photographs, making written notes, taking measurements, etc. Our task was to observe the changes in the wetland, who was using it for food or shelter, what was growing there and when it began coming up in the spring, how had it changed since the land was settled?
I found phenology journaling to be very useful and could help us to track the impacts of climate change on both our native and invasive flora and fauna. Check out the higher education resources available online from the National Phenology Network: https://www.usanpn.org/education