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Food Preferences Among the Crab Species at Elkhorn Slough

Student(s):Alejandra Castro, Paloma Espiritu, Crystal Gallardo, and Elsy Romero
Grade Level:Secondary School (grades 9-12, ages 14-18)
GLOBE Educator(s):Satina Ciandro
Report Type(s):Standard Research Report, U.S. Student Research Symposia (SRS)
Protocols:Dissolved Oxygen, Salinity
Date Submitted:06/17/2020
Taking Water Sample
● With our background research, our group addressed the impact of invasive species on the Elkhorn Slough ecosystems. ● European Green Crab is an invasive species originally from the northeastern coast of Europe that was accidentally transported to the East coast of the U.S. ● The European Green Crab, like other invasive species, have shown signs of killing off native species such as the Yellow Mud Crab, Striped Shore Crab, and the Pacific Rock Crab because of the lack of predator threats that they receive. ● Our group researched food preference among crab species with the intention of finding the preference of the invasive European Green Crab. ● Testable Question: Does food preference affect the abundance and richness of crabs at Elkhorn Slough? ● Hypothesis:We think the anchovies or the white fish cat food would be the bait of choice because both baits are aquatic species which could resemble the fish species within the slough. ● Our research was meant to help scientists with the removal of invasive species from the infested areas due to the harm they might cause and ensure the safety of ecosystems within the slough.


Hi, my name is Z and I currently work on wetland habitat restoration. I received my masters in biological oceanography from UCSC. You organized your poster well and your figures are clear. I especially enjoyed seeing pictures of you working on your project. You briefly mention that salinity and tidal cycle may affect crab abundance. Did those factors affect all species? What other factors might influence crab abundance and species richness? For future work, I suggest testing with other food types. By removing invasive green crabs, you would be influencing subsequent catches. It is great that you were already accounting for this by considering spread traps further apart in the future if you were to continue your study. Great job overall!
Hello Alejandra Castro, Paloma Espiritu, Crystal Gallardo, Elsy Romero,

My name is Acy Wood and I am a Masters student at Moss Landing Marine Laboratories and a Research Fellow for the Smithsonian Environmental Research Center. My background is in phycology, the study of algae, but I love crabs and had a great time reading your work! I appreciated how you walked us through the though process as to why you selected the food you did and how you highlighted a species that warrents monitoring by local stewards, like yourselves. If you ever planned on redoing this study, I would suggest finding some way to investigate or explain how the environmental conditions you recorded, the O2 and salinity, may have affected the data you gathered for the day. Maybe one kind of crab is more active than another on a rainy day? Overall, you should be proud of the work you accomplished. You had a great layout for your poster as well. Great job, team!
Hi Alejandra, Paloma, Crystal, and Elsy,
My name is Eliza Balch and I am a master's student and the University of New Hampshire. I studying water chemistry and water resources. My research focuses on nitrogen pollution in freshwater and where, when, and how the nitrogen is processed. I also work at Great Bay National Estuarine Research Reserve, which is part of the same network of estuary reserves as Elkhorn Slough!
I really enjoyed reading about your research on food preference of crabs. Your poster was well-organized and easy to follow, outlining your research question and hypothesis and following up on them in your reselts and discussion. I found your research to be very interesting and you did a great job explaining the necessary details. You did well communicating the significance of your research project to the reader, that understanding food preference of the different crab species can help manage and trap the invasive green crab. My favorite part of your poster is all of the visuals you used, of all of you at work, the trap, and the map of all of your traps. They really helped me visualize your location and methods. One improvement you could make in future posters would be to make a legend with the names of the species, since your reader may not be familiar with the abbreviations your used. It would also be interesting to hear why you separated your crabs by sex, and if you noticed any trends in the sex data. Overall, I found your poster visually appealing and your story to be very detailed and informative, contributing to a very positive and effective research presentation. Great Job!
My name is Melody Keena and I am a Research Entomologist working for the Forest Service in Hamden, CT. My web page is I read your poster and enjoyed it. You had a good study design and as you mention spacing of the traps could help. Your photos are great at telling your story. I would encourgae you to continue studing nature and to learn statisitics since they are very important to scientific studies.