Biodiversity And The Revitalization Of The LA River

Overview & Background

For this assignment, we will be focusing on one of the goals of the Los Angeles River Revitalization Master Plan: to revitalize the river by improving water quality and restoring a functional ecosystem.

For this assignment, you will again focus on the animal species you selected for LA River Species Selection discussion. Some of you have been researching a native species that is found along the Los Angeles River, while others have been researching a Introduced species. As such, you are going to approaching revitalization of the river from different perspectives.

There are two parts to this assignment. First, to better understand the ecological impacts of the concrete channelization of the river, you will explore iNaturalist and look at the distribution of your species in channelized areas. Second, you will provide an analysis of the revitalization. The instructions below will walk you through each part.

Links to iNaturalist places for the two channelized stretches of the Los Angeles River that we will focus on:

Links to iNaturalist places for soft-bottom stretches of the Los Angeles River:

Assignment Requirements

Part 1: Exploring the your species distribution using iNaturalist and graphing

Use the links for the channelized locations in the LA River Los Angeles River – Universal City and Los Angeles River – Downtown. Type the name of your species into the species box to see the number of observations of your species found in these two locations. Record the following information for EACH location:
- How many observations are there of your species in the channelized sections of the river?
- Save a picture or screenshot of a map of iNaturalist observations in the two channelized stretches of the Los Angeles river.
Use the links for the soft-bottom locations in the LA River Los Angeles River – Elysian Valley and Los Angeles River – Sepulveda Basin Wildlife Reserve. Type the name of your species into the species box to see the number of observations of your species found in these two locations. Record the following information for EACH location:
- How many observations are there of your species in the soft-bottom sections of the river?
- Save a picture or screenshot of a map of iNaturalist observations in the two soft-bottom stretches of the Los Angeles river.
Create a column graph that compares the number of observations of your species in the two channelized stretches of the LA River with the number of observations of your species in the two soft-bottom stretches of the LA river. Be sure to properly label the x- and y-axes.
- Based on these data, do you think your species is common or rare in the concrete channels?
- Based on these data, do you think your species is common or rare in the soft-bottom sections?
- Do you see a difference in the number of observations of your species in the soft-bottom vs. channelized sections? If so, propose an explanation for why that difference might exist, or if there is not one why might this be? In your explanation, consider factors like, the quality of the habitat, the number of observation-collecting visitors to each of these locations, etc.
- Is the pattern of observations for your species in the soft-bottom and channelized sections similar to that for other species in your taxonomic group – mammals, birds, insects, fish or reptiles/amphibians (type this into the ‘Species’ box, see Species Selection assignment from last week for more detailed directions). Is the pattern for the total number of observations (of ALL species) for each of these sections similar? Propose an explanation for why the pattern for the number of observations might be similar or different for other species in your taxonomic group or for all species.

Part 2A: Planning for revitalization

Very important: Complete Part 2A if your species is NATIVE to the LA River. Skip this section if your species is INTRODUCED to the LA River

From the list below, choose the two restoration actions that you believe would have the largest positive impact on your species.
- Planting more native plants and trees
- Increasing habitat connectivity by connecting smaller patches of habitat
- Removal of invasive plant species, including trees, shrubs, and weeds
- Installation of boulders, rocks, and logs to create microhabitats
- Installation of more trash screens on storm drains to reduce trash flowing into the river
For each of the restoration actions that you chose, write a 3-5 sentence explanation of how this action would benefit your species. You should reference specific aspects of the species’s biology and ecology from your Individual Species Research. The explanation for each restoration action must include at least one in-text citation.

Remember to cite all sources fully, including in-text citations and a properly formatted reference list at the end, for full credit. Please make sure that your sources are credible and that you properly cite all sources.

Part 2B – Planning for revitalization

Very important: Complete Part 2B if your species is INTRODUCED to the LA River. Skip this section if your species is NATIVE to the LA River

Should your species be eradicated from the LA River?
- What would be two benefits for the LA River ecosystem if your species would be removed? Write a 3-5 sentence explanation of how your species could be damaging the LA River ecosystem. As an example, think back to the crayfish paper we read. Does your species feed on native species? Does it compete with it?
- What would be two costs to the LA River ecosystem if your species would be removed? Write a 3-5 sentence explanation of how the removal of your species would hard the LA River ecosystem. As an example, many native predators may now eat Introduced species or Introduced species may actually improve the habitat along the river.
You should reference specific aspects of the species’s biology and ecology from your Individual Species Research. The explanation for each must include at least one in-text citation.

Submission Guidelines

Upload your answers for Part 1 and Part 2 of this assignment (including maps and graph) as a Word document or as a pdf. Please clearly number your answers.

Grading

To see how this assignment will be graded, scroll down to view the grading rubric. If no rubric is visible, click on the three dots in the upper right corner of this page, then click “Show Rubric”. If you’re reviewing this assignment using the Canvas mobile app, the rubric is included in the Grade tab.

Note: While I am not specifically grading you on your spelling or grammar, scientific communication is an important skill. Please proofread and spellcheck before submitting to ensure that your ideas come across clearly. Up to 10% may be deducted for excessive grammar and spelling errors that affect the readability of your work.

Helpful Resources

Image credit: USDA National Agroforestry Center. Accessed from Conservation Buffers, https://www.fs.usda.gov/nac/buffers/guidelines/2_biodiversity/3.html (Links to an external site.). This image is in the public domain.