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Home , American lobster, Procambarus clarkii

Elias Kane Science Fair Final Draft I. Problem:

Which environmental factor: pH, or the presence of the pesticide methoprene most inhibits the American ’s ( americanus) growth rate as modeled by the Red Swamp ( clarkii)?

II. Collected Information

Long Island Sound serves as a prime habitat for thousands of due to its relatively protected waters and stable environmental conditions. The (Homarus americanus) is one of the most integral scavengers of . In addition, the American lobster is a backbone of much of northeastern . Prior to 1999, in combined Connecticut and New York waters, the total lobster catch was between 7-11.7 million pounds. In 2004, the total lobster catch had fallen to 1.6 million pounds (Balcom &Howell, 2006, p. 1). This is due to a large American lobster die-off in late fall of 1999. Long Island Sound is in the southern extent of the American lobster’s range. Due to this fact, the temperature is considered likely to cause the organisms stress. Die-offs of the American lobster population have happened in the past, just never in the same magnitude as that of 1999 (Balcom & Howell, 2006, p. 5). Temperature as well as many other factors worked together to cause this particularly massive die-off. Several harmful variables in Long Island Sound led to the death of millions of . Climate change, in the form of temperature rise and , pesticide, shell disease, and parasitic amoebae which cause paramoebiasis, all led to this die-off (Balcom & Howell, 2006, p. 2). Paramoebiasis is a lethal disease that infects susceptible lobsters and eventually kills them. While the cause of death of the majority of the lobsters was proven to be paramoebiasis, there is still contention and debate over what was the most influential factor in its spread. Ocean acidification is a process in which our oceans absorb carbon dioxide from the air and store it as carbonic acid. This can cause basic shells to take longer to grow and develop in an acidic environment (“How to Take Care of Crayfish”, 2014). and thrive in basic or neutral waters due to the composition of their shells. The lobster and crayfish’s hard are made of calcium carbonate, a basic compound. The pH of ocean waters across the world are falling due to increased levels of carbon dioxide in the atmosphere. As the ocean Elias Kane Science Fair Final Draft becomes more acidic, its inhabitants are forced to migrate, adapt or die. Ocean acidification causes a basic to deteriorate. The summer of 1999 was riddled with cases of West Nile virus, which is transferable through mosquitoes. In an effort to abate the spread of disease, the government sprayed copious amounts of pesticide. In mid-September, Hurricane Floyd washed the pesticides and other lethal chemicals into Long Island Sound (Dellinger, 2012, p. 581). Reports of dead and dying lobsters surfaced just days later. Methoprene, the active ingredient in much of the sprayed pesticide, is a known . It is supposed to target pests in their larval stage, but is truly indiscriminate in which species it kills. It is lethal to lobsters at one part per billion (Dellinger, 2012, p. 581). Lobstermen often blame methoprene and other pesticides for the fishery tragedy of 1999. Scientists, on the other hand, are split on the cause of this mysterious die-off. Some blame climate change, while others point fingers at pesticide, and several others blame an insurgence of epizootic bacteria and parasitic amoebae into Long Island Sound. Epizootic bacteria, the bacteria that causes lobster shell disease, thrives in warmer climates. In this way, climate change and shell disease are linked. Lobster shell disease is not a cause of death in lobsters. Instead, it opens up lesions in a shell and allows for the infection of opportunistic diseases. The warmer climate also allows for a heightened rate of spread of disease (Dellinger, 2012, p. 581). The contention over the cause of death in the die-off is still present to this day. Both the American lobster (Homarus Americanus) and the Red Swamp crayfish () are members of the subphylum Crustacea. Due to their common ancestry, they have similar physical and metabolic characteristics. In addition, they have similar reactions to environmental stressors (Reiber & McMahon, 1998, p. 168). They also possess analogous cardiovascular and respiratory systems. In environments with stressful conditions, both lobsters and crayfish at first start to hyperventilate. After getting used to the stressors, they go into lessened metabolic states (Reiber & McMahon, 1997, p. 168). The American lobster and the Red Swamp crayfish have many physiological and metabolic similarities. Both crustaceans react similarly to environmental stressors.

Elias Kane Science Fair Final Draft III. Hypotheses a. If Procambarus clarkii is exposed to more acidic conditions, its growth will be the most stunted because it will slow down the growth of a crayfish’s basic shell. b. If Procambarus clarkii is exposed to methoprene, its growth will be the second most stunted and there will be a heightened mortality rate because it is lethal at small doses. c. If Procambarus clarkii is exposed to either environmental stressor, its growth rate will be lowered, relative to the control, because of the effects of methoprene and acid on crustaceans. IV. Experimental Design

V. Procedure a. Collect materials i. 12 Procambarus clarkii specimens ii. 3 small tanks with space for 4 specimens marked one for each variable, and the control Elias Kane Science Fair Final Draft iii. Food for 12 crayfish for 1 month iv. Methoprene diluted to 1 ppb v. Carbonic acid vi. Caliper vii. Electronic balance viii. pH paper ix. micropipette x. micropipette tips xi. jar for toxic methoprene waste xii. 4.5 liters of dechlorinated water every other day b. Fill the tanks with 1.5 liters of dechlorinated water. c. Dilute methoprene to 1 part per 2 billion and add into a marked tank d. Add carbonic acid to the water of one of the marked tanks until the pH falls to 6, as determined by the pH paper. e. Leave one tank with pure dechlorinated water. f. Mass the crayfish in grams. g. Measure their length with calipers in centimeters (from eye to end of tail). h. Record the data. i. Feed each crayfish one sinking food pellet per day. j. Change the water in the tanks every two days, but maintain the environmental conditions. k. Mass and measure each crayfish at the zero, one, two, three, and four week marks. l. Record all data and graph.

Elias Kane Science Fair Final Draft

VI. Variables a. Independent Variables i. Methoprene ii. Acidity b. Dependent variable i. Growth of the crayfish per week c. Constants i. Dechlorinated water environment ii. Food amount iii. Food iv. Shape and size of environment v. Water change frequency vi. Stage of life (juvenile) that the crayfish is in vii. The measurements used to determine growth d. Control i. The experiment conducted on crayfish without environmental stressors

Elias Kane Science Fair Final Draft VII. Data Tables

Table 1 Week Week Week Week Week

Week # Control 0 1 2 3 4 Organism 1 .85 g .83 g .93g .90g .96g

(Weight(g)/ 3cm 3.25 3.5cm 3.5cm 3.8cm length(mm) cm Organism 2 .48g .49g .49g .56g .58g

2.5cm 2.75cm 3cm 3.2cm 3.5cm Organism 3 .96g .93 1.01g 1.13g 1.13g 3.25cm 3.5 cm 4cm 4cm 4cm Organism 4 1.47g 1.38g 1.42g 1.65g 1.79g

4.2cm 4.2 cm 4.5cm 4.8cm 5cm

Table 2 Week Week Week Week Week

Week # Acid 0 1 2 3 4 Organism 1 1.60g 1.86g 1.93g 1.91g 1.85g

(Weight(g)/carapace 4cm 4.2cm 4.5cm 4.5cm 4.5cm length(mm) Organism 2 1.33g 1.28g 1.30g 1.31g 1.33g

4cm 4cm 4.5cm 4.5cm 4.5cm Organism 3 1.84g 1.76g 1.84g 1.83g 1.78g 4.5cm 4.5cm 4.5 4.5cm 4.5cm cm

Organism 4 0.79g .77 g .77g .84 g .76g 2.8cm 3.2cm 3.5cm 3.5cm 3.5cm

Elias Kane Science Fair Final Draft

Table 3 Week Week Week Week Week Week # Methoprene 0 1 2 3 4 Organism 1 2.49g 2.43g 2.49g 2.48g 2.47g (Weight(g)/carapace 5cm 5 cm 5cm 5cm 5cm length(mm) Organism 2 1.76g 1.83g 1.85g 1.77g 1.78g 4cm 4.2cm 4.5cm 4.5cm 4.7cm Organism 3 0.11g .17g .15g .12g .12 g 1.6cm 1.8cm 1.7cm 1.8cm 1.7cm Organism 4 1.22g 1.27g 1.33g 1.24g 1.23cm 3.8cm 4cm 4cm 4cm 4.2cm Elias Kane Science Fair Final Draft

VIII. Graphs

Fig. 1: Total Mass Growth of P. clarkii 0.2

0.18

0.16

0.14

0.12

0.1

0.08 Growth in Grams 0.06

0.04

0.02

0 1 Control Growth in Grams 0.175 Acid Growth in Grams 0.04 Methoprene Growth in 0.005 Grams Environmental Condion

Elias Kane Science Fair Final Draft Fig. 2 Weekly Mass Growth (gm) of P. clarkii

0.12

0.1

0.08

0.06

0.04

0.02

0

-0.02

-0.04 Weekly Growth (gm) -0.06 1 2 3 4 Control Growth in Grams -0.0325 0.055 0.0975 0.055 Acid Growth in Grams 0.0275 0.0425 0.0125 -0.0425 Methoprene Growth in 0.03 0.03 -0.0525 -0.0025 Grams

Week # Elias Kane Science Fair Final Draft Fig. 3 Total Growth in Length (cm) of P. clarkii

) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1

Length Growth (cm 0 1 Control Growth in 0.8375 Cenmeter Acid Growth in Cenmeters 0.425 Methoprene Growth in 0.3 Cenmeters Environment Elias Kane Science Fair Final Draft Fig. 4 Weekly Length Growth (cm) of P. clarkii 0.35

0.3

0.25

0.2

0.15

0.1 Length Growth (cm)

0.05

0 1 2 3 4 Control Growth in 0.1875 0.325 0.125 0.2 Cenmeter Acid Growth in Cenmeters 0.15 0.275 0 0 Methoprene Growth in 0.15 0.05 0.025 0.075 Cenmeters Week #

IX. Observations & Analysis a. Throughout the experiment, the results indicate that methoprene, and a more acidic environment both consistently stunt the growth rates of Procambarus clarkii. Methoprene most affects the growth rate, with both the lowest mass and length growths being exhibited in the methoprene environment. A more acidic environment, affected the growth rates of the crayfish to a lesser extent than methoprene. Growth rates observed in the acidic environment were higher than that of methoprene, but still considerably lower than the control environment. With the exception of the first week, when the crayfish were still becoming acclimated to their environments, the control group outgrew both those exposed to Elias Kane Science Fair Final Draft an acidic environment, and methoprene. No deaths occurred in any of the treatment groups during the experiment, and the mortality rate was zero. There was significantly more growth in the control group as opposed to the acidic group and the methoprene group. X. Conclusion

The produced results did not confirm all of my hypotheses. I hypothesized that the growth rate of those exposed to an acidic environment would be most affected. In addition, I hypothesized that the growth rate of those exposed to methoprene would be the second most affected. It was also hypothesized that the mortality rate of those exposed to methoprene would be higher. Due to the results, in which those exposed to methoprene had a more stagnant growth rate, my hypothesis was not verified. As well, I had a mortality rate of zero, which goes against my hypothesized heightened mortality rate. However, both methoprene and acid lowered growth rates in P. clarkii. These results are consistent with my third hypothesis. I hypothesized that the environmental stressors would lower the growth rates of P. clarkii. The growth observed in my experiment confirmed my third hypothesis.

This experiment went relatively smoothly, however there are still changes that would have been beneficial. Prior to the experiment taking place, I set up my tanks, and practiced changing the water, to make sure that the experiment would run easily. Looking back, however, I wish I had set up the actual organisms in the tanks, at least one week earlier, as to acclimate and adjust them to their respective, new, environments. After only three days of experimentation, I realized that water quality became very poor just after the feeding time. In order to account for this, I changed the water on an as needed basis. Typically, the water was changed on a daily basis, on week days, and not changed on weekends, as the tanks were inaccessible on these days. Likewise, the crayfish were only able to be fed on weekdays.

At the beginning of my experiment, I planned to investigate two other variables, temperature, and the presence of a shell disease causing bacteria known as Elias Kane Science Fair Final Draft epizootic bacteria. Unfortunately, due to safety issues, and a much more complex setup, I was unable to investigate these variables. If I were to repeat this experiment, I would look forward to investigating the effects of these variables on growth.

This experiment was designed to take a look at two of the leading environmental stressors that have, in the past, led to massive lobster die offs in Long Island Sound. The two independent variables investigated link directly to ocean acidification, caused by increased carbon dioxide in the waters, and pollution, caused by an assortment of chemicals and pesticides similar in nature to methoprene. Procambarus clarkii was used as a model organism, with a metabolic reaction mirroring that of the American lobster. Due to all of these facts, we can extrapolate the results of these experiments to the lobster population in Long Island Sound. Although methoprene affected the growth rates the most, both similar pesticides and the falling pH are dangerous to the growth and development of crustaceans. Lowered growth rates can affect all parts of an organism’s life. Lowered growth can lead to heightened predation as well as higher mortality rates. It can cause the organisms to be less effective predators. In addition, these environmental changes affect all species, such as prey and food sources, in the lobster’s habitat. Environmental change can hurt food webs and ecosystems.

In our pollutant producing society, and during a time of changing climate that is making aquatic environments more acidic, both of these variables are increasingly important to our neighboring ecosystem. Long Island Sound is the life of this region, and my experiment shows that the presence of methoprene and an acidic environment will lead to its death.

Elias Kane Science Fair Final Draft References: Dellinger, L. (2012). A Fishermen’s Perspective. Journal of Shellfish Research, Volume 31 (2), 581-582. Balcom, Nancy, and Penelope Howell.(2006) Responding to a Resource Disaster: American Lobsters in Long Island Sound. 2-15. Reiber, C.L. and B.R. McMahon. (1998). Progressive hypoxia effects on the cardiovascular system: a comparison of the freshwater crayfish (Procambarus clarkii) and the lobster (Homarus americanus). Journal of Comparative Physiology B., 168: 168- 176. Pierce, J. (n.d.). Crayfish Basics. Retrieved October 19, 2014, from http://www.wetwebmedia.com/ca/volume_5/volume_5_3/crayfish_basics.htm How to Take Care of Crayfish. (n.d.). Retrieved October 19, 2014, from http://www.wikihow.com/Take-Care-of-Crayfish