Our group had to conduct this field visit to a freshwater habitat to get hands-on experience about local habitats and the animals and plants around it. We think that going to the site and observing the animals, plants and the habitat will make it a interesting learning experience since we are allowed to actually here and everything is real-life not just pictures or words in a textbook. Also, our group wants to learn the proper methods to observe and examine the habitat without causing any damage to the area.
During the field trip, we saw a variety of organisms along and in the stream. There was difference in what we found in the upper and lower stream. The upper stream had fishes, more lichen, insects, snails and crabs. In the lower stream, we only saw snails under the rocks, comparatively less lichen and crab holes in the sand along the coast of the stream so we deduced that crabs can also be found in the lower stream.
After doing some research, we have found out more about each kind of organism found in the stream.
Lichen is found everywhere along the stream, especially concentrated in an end of a branch extended from the upper stream. It usually sinks and stays on, but not stick to the rocks under and around the water.
Lichen produces nutrients through photosynthesis. In this process, what they need from the atmosphere will be the moisture provided by the water, minerals from the rocks and organic fragments. This rocky river stream becomes a very ideal habitat to the lichen. At the end of the extended water branch, as some organic nutrients like dead body of other organs accumulate there, lichen is particularly abundant.
Freshwater snail is found in both upper stream and lower stream. Their size is rather tiny, which is only a diameter of around 1cm. They are found under water, in very dark colors similar to the rocks they lie on.
The living condition of freshwater snails is a shallow and rocky river stream. Their dark protective colors makes them invisible on rocks enable them to hide from their predators. By eating vegetables like lichen along this river stream, the nutrients from lichen allow them to grow. Their tiny size is probably due to the nutrition competition in between the large amount of freshwater snails existing there.
The freshwater snails found in the lower stream tends to have white nicks and scratches on their shells, while those in the upper stream are more intact. We believe that when the freshwater snails from the upper stream flow with the water, as they are pushed, their shells and the rocks under water keep milling. Their shells are inevitably nicked and scratched by the rough surfaces of the rocks. Therefore, freshwater snails found in the lower stream are usually no longer intact.
During the field visit, we discovered insect eggs on the underside of the rocks. This meant that insects laid eggs in the stream. We also saw a long insect between the rocks.