The purpose of my lab was to find the preferred habitat of the Asian shore crab. I collected data on Asian shore crabs from Vital Signs and graphed it in to multiple histograms including the pH, dissolved oxygen, salinity, temperature, and landscape of the water they were found in. I found an average pH of 7.7, an average dissolved oxygen of 9.2 ppm, an average salinity of 30.6 ppt, and a landscape majority of rocky intertidal. This shows
Asian shore crabs prefer a low pH and a high temperature.
Certain species are adapted to thrive in certain habitats, and we must know what these species are in order to protect them. The Asian shore crab has been invasive to the United States since 1988. “Because this species has a very broad diet, it has the potential to affect populations of native species such as crabs, fish, and shellfish by disrupting the food web,” an article from the South East Ecological Center stated. I have decided to study the type of habitat that Asian Shore Crabs prefer in the Maine coast. This will help correlate changes in the ocean with the changes in the Asian shore crab population. It also might answer the question of why they came to Maine. For example, if global warming caused their native habitat to become uncomfortable, they might have moved to Maine to avoid it.
Question: What type of habitat do Asian shore crabs prefer in coastal
Maine?
Hypothesis: I predict that the Asian shore crabs will prefer the typical
Maine climate because an invasive species invades a coastline because it’s comfortable there. So I, predict that they will like up to seventy degrees
Fahrenheit water temperature, an average pH of 8.1, and a rocky intertidal landscape.

My method was to collect as much data on Asian shore crabs as possible from the GMRI’s Vital Signs website. I recorded the water temperature, pH, dissolved oxygen, salinity, and landscape of the site where it was found. I made this data into separate histogram charts to show where the data clustered so I could see what the most popular habitat.
The average temperature was higher than I expected: about 15.6 degrees
Celsius, which is 60.08 degrees Fahrenheit. The average PH was fairly low: from 6 to 8.2. The dissolved oxygen and salinity were normal: with averages of 9.2 and 30.6 respectively.
Results:
Average water temperature— 15.6 degrees Celsius (60.08 degrees
Fahrenheit)

Average PH— 7.7 (typically 8.1)
Average dissolved oxygen— 9.2 ppm.

Average salinity— 30.6 ppt.
Landscape majority— rocky intertidal, minority: beach/dune

What type of habitat do Asian shore crabs prefer? I hypothesized that they would prefer the typical Maine climate because an invasive species invades a coastline because it’s comfortable there. That includes a PH of 8.1, a water temperature up to seventy degrees Fahrenheit, and a rocky intertidal landscape. I was surprised to find that my average water temperature and average PH did not support my hypothesis.
Average water temperature— 15.6 degrees Celsius (higher than the typical
Maine water temperature)
Average pH— 7.7 (typically at 8.1)
Average dissolved oxygen— 9.2 ppm.
Average salinity— 30.6 ppt.
Landscape— majority: rocky intertidal, minority: beach or dune
Problems: The reason that the pH might be high is that shallow, coastal water evaporates more making the water more acidic. The water

temperature being high might have to do with the time of year that it was measured. If it was fall, the water would be warmer.
Application: Many scientists wonder why Asian shore crabs are invasive in
Maine. My theory is that they came on boats to New Jersey, but as global warming caused the ocean temperature to rise, they migrated to Maine, as the waters warmed too much in the south.
Further studies: If they Asian shore crab population in Maine suddenly decreases, scientists can look to this data to find any correlation between climate change and Asian shore crab populations. For example, if the temperature decreases and Asian shore crab populations drop, we will know why. We also know that they are currently damaging Maine’s biodiversity, so we should make sure not to cause global warming that forces them to migrate from their native climate.