Critique on Myers et. al.

In my article titled "Great Sharks"  I introduced a case of top down forcing that occured on the United States Atlantic coast.  In it I discussed a report titled "Cascading Effects of the Loss of Apex Predatory Sharks from a Coastal Ocean" written by world renowned marine biologist Ransom A. Myers and his research team at Dalhousie University.  It synthesized seventeen different surveys of large shark populations beginning before 1990 including UNC's continuous shark survey reported annually from 1972 to 2005 (Myers 2007).  This chart provides a quick summary:

 My Personal Contribution

Looking into this matter further, I feel as though numerous other occurrences over the past 20 years could have lead to the huge decline of bay scallops and the closure of the numerous scallop industries.  The ocean is an extremely complex system with thousands of inputs and outputs.  Also, through my research on top down forcing, I have definitely noticed that terrestrial ecosystems have explored much further when it comes to the subject of trophic cascades.  This could be for a number of reasons.  I want to investigate possible other occurrences along the Atlantic coast that could provide further explanation and new understanding as to how scallop populations declined so dramatically.

Red tide is a well understood type of algal bloom in which the marine dynoflagellate, Karenia brevis, undergoes rapid growth creating coastal waters with a red or brown color ("Harmful Algal Blooms").  K. brevis produces a powerful nuerotoxin called brevatoxin that have been shown to have negative impacts on the health of many marine species.  Filter feeders, scallops included, are very sensitive to toxicity levels and can acumulate toxic levels in their tissues and can subsequently die (Red Tide Research Center).  When humans consume shellfish that has high enough levels of brevatoxin, Paralytic Shellfish Poisoning can result.

I have found a report to stakeholders written by the Red Tide Control and Mitigation Program in Florida.  It combines data from a information from fisheries surveyed from 2007 to 2009 in an attempt to illustrate the harmful effects of algal toxin on shellfish, such as the Bay Scallop.  Below is a personal contribution.

Red tide has occured periodically throughout U.S.'s Atlantic coast, with far reaching and devastating effects.  I have shown below that these events have increased during the same time  of Bay Scallop decline.  Also I have compiled data of Atlantic hurricanes and tropical storms from the National Oceanic and Atmospheric Administration.  After placing the data in a graph, one can see the increased abundance of these weather events.  I believe that this could be another possible explanation for the decrease abundance of the Bay Scallop.  Bellow I have constructed an chart that synthesizes research from the Atlantic coast for one of my personal contributions.