Learning Target

• Investigate the technologies that have changed the way humans influence the inheritance of desired traits in organisms. 

Success Criteria

• Students gather information about a technology that has changed the way humans influence the inheritance of desired traits in oysters

• Students use their understanding of genes and heredity to identify ways in which humans influence the inheritance of organisms.

Oyster Management Plan

Spend Your Money Wisely!

Introduction

• You are part of a team that has been tasked with the job of increasing the population of Eastern Oysters in Chesapeake Bay.  You have been given a total of $35,000,000 to spend as you see fit.  You have 6 options as detailed below.

• Read the options and decide how you will use your money.  You may spend as much of the money as you would like.  You may only use each option once.

• Prepare a brief presentation to explain what your team will do and why you chose each course of action.

Options

1. Plant and Move (cost - 3 million) Seed oysters are moved from public grounds to leased grounds with higher salinity waters favorable for growth.  Then, before reaching marketable size, the oysters are moved again from the higher salinity waters in order to inhibit mortality rates from either MSX or Dermo.  Method works fairly well in the short term, depending on climate changes and timing of the moves.  However, this method does little to either eliminate the diseases or increase the oyster’s resistance.

2. Breeding for Resistance (cost – 9 million) Researchers breed specific strains of oysters in hatcheries, which are then planted in the Bay.  Method is showing some success against MSX in particular, but still in its infancy against Dermo.  In the long term, should solve the disease problem, depending on how other factors, such as ecosystem stress in general, affect the oyster’s immune system.

3. Reducing Ecosystem Stress (cost – 7 million) Factors that are negatively affecting the ecosystem in general are addressed.  For instance, reducing nutrient loads to the Bay, and thus reducing problems caused by eutrophication, will increase the ability of the oyster to resist disease because the oyster’s immune system is stronger in a high-oxygen environment.  Reducing ecosystem stress will benefit many other resources.  Determining all the causes of the stress and establishing appropriate legislation and policies is difficult.

4. Raise Disease Free Oysters in Hatcheries (cost – 15 million) The difficulties with this method are making sure the oysters are indeed disease free, and raising a significant number of oysters in this manner.  Keeping a healthy population of disease free oysters may be important to re-establishing healthy population in the Bay.  (The difference between this and #2 is that the oysters would be kept at the hatcheries.

5. Finding a cure for the Dermo and MSX (cost 11 million) Researchers are learning more about the working of MSX and Dermo at the molecular level.  If this method is successful there may be no need for breeding programs in the long term.  Difficulties will be in practical applications of the cure, whatever it may be.

6. Harvesting Regulations (cost – 3 million) If the harvesting of oysters is severely restricted over a significant number of years, the oyster population may rebound.  However, the oyster industry, and those who depend on it, will be very significantly and negatively impacted.