Baby Billfish – Figuring Out Who’s Who

An important part of any fishery management plan is the definition of “essential fish habitat”.  For many coastal fishes there are specific environments critical for spawning, nurseries, feeding, etc., and these areas need to be protected if the species are to remain at healthy levels.  The question is, do open ocean fishes such as tunas and billfish also have specific essential habitats?”   

“In the case of billfishes, the bottom line is that we don’t know enough about their life histories, facts like where and when they spawn or where their larvae and juveniles live, to enable us to define essential habitats,” said Dr. John Graves, Head of the Fisheries Genetics Laboratory at the Virginia Institute of Marine Science (VIMS).  A major impediment to studying the early life histories of billfish is that it is extremely difficult to identify larval and juvenile billfish.  The larval forms don’t look at all like adults, and most larval fish biologists agree that the physical characters currently used to distinguish among the species are suspect.

Fortunately, fish biologists have a whole new arsenal of molecular characters to help with identifications.  For several years, researchers in the Fisheries Genetics Laboratory at VIMS have been developing molecular markers to identify the different billfishes.  Ph.D. student, Jan McDowell determined that the molecular techniques for identifying billfishes would most likely work with larval billfish.  To pursue this research, McDowell began working with colleagues at the Rosensteil School of Marine and Atmospheric Sciences (RSMAS) of the University of Miami and has now developed molecular markers to identify billfish larvae.  This definitive identification will give scientists information about when and where billfish spawn.

 Spawning information will provide one piece of the habitat puzzle, putting scientist closer to determining if specific habitats are critical for billfish.  Still, there is a lot that is not known about the early life history stages.   “We don’t have a good idea where they live, what they eat and how fast they grow. This is essential information for developing management plans for a sustainable fishery,” said Graves.

VIMS Named World Reference Laboratory For Shellfish Diseases 

The Virginia Institute of Marine Science has been designated as the only world-wide
reference laboratory for two groups of pathogens, (Perkinsus and Haplosporidium), that cause diseases in shellfish all over the world. Dr. E.M. Burreson, VIMS Director of Research and Advisory Service, was named the Reference Expert. The designation was announced by the Office International des Epizooties (OIE), a Paris based international advisory organization on infectious animal diseases. OIE is the official arbiter of the World Trade Organization for issues involving living animal products, including wild or aquacultured marine animals. 

Species of Perkinsus and Haplosporidium are responsible for the oyster diseases Dermo and MSX that continue to cause tremendous mortality in oysters in Chesapeake Bay. Native and cultured abalone in Australia and New Zealand are affected by diseases caused by species of Haplosporidium while species of Perkinsus are causing diseases in oysters and clams in Japan, Korea, France and Spain and in cockles in New Zealand. While these diseases have no affect on humans, they can decimate shellfish populations and cause economic havoc in both fisheries and aquaculture industries. 

OIE recruited VIMS for reference laboratory status based on the Institute's long history of research on Perkinsus and Haplosporidium and because of current research and international collaboration on diagnosis of diseases caused by these organisms. Molecular diagnostic (DNA) tools for identifying these disease agents developed at VIMS by Burreson, Dr. Kimberly Reece and Ms. Nancy Stokes, are being used world-wide. 

"This is a real honor, in recognition of the significant breakthroughs we have made at VIMS in the diagnosis of these shellfish pathogens that occur world wide", Burreson said. "It will also mean some additional work, but we have a great team in shellfish pathology and we are glad to be of service to the international community." 

Reference laboratories serve as an advisory resource for the OIE and as an identification resource for researchers around the world. The labs are also obligated to develop and standardize diagnostic protocols for relevant disease agents and to provide a diagnostic service for researchers around the world. OIE has been responsible for promoting and coordinating research into the surveillance and control of animal diseases throughout the world since 1924. 

Serious diseases that should be contained from accidental geographic spread are designated "notifiable" by OIE. This designation can restrict the export of animal products from a country that has the disease. Perkinsus and Haplosporidium are found worldwide and cause notifiable diseases. "We are already receiving requests and samples from around the world," Burreson said. 

To learn more about OIE see their web site at www.oie.int

VIMS Environmental Scientists Author New Risk Assessment Book

Risk assessment is the cornerstone of contemporary environmental protection. Despite recent progress, implementation of the ecological risk assessment paradigm to coastal and estuarine ecosystems still lags behind that for freshwater and terrestrial systems. This book was developed to eliminate this imbalance. Written by Dr. Morris Roberts, Chair, Department of Environmental Sciences, Dr. Michael Newman, Dean of Graduate Studies and Associate Professor Robert Hale, the book discusses the development of fundamental concepts related to chemical risks from the molecular to the landscape level.  It also covers early recognition and evaluation of exposure to new use chemicals before they reach critical levels.

“Understanding and assessing these risks is essential to sound environmental policy and management,” said Newman who has also authored other books on risk assessment.  The team drew examples from their varied career experiences as well as from diverse North American and European ecosystems.

Newman is also the author of the very well known and widely acclaimed “Fundamentals of Ecotoxicology,” which is considered to be the most comprehensive textbook or working reference in the new science of toxicants in the environment. The book is available through Lewis Publishers