home | marine biotoxins program | ccehbr

Resources

Ocean Literacy Standards

Ocean Literacy Standards (note: opens in a new window)

Ocean Literacy Definition
Ocean literacy is an understanding of the oceans influence on you and your influence on the ocean.
An ocean-literate person understands:

• the essential principles and fundamental concepts
• can communicate about the oceans in a meaningful way
• is able to make informed and responsible decisions regarding the oceans and its resources.

Seven Essential Principles

1. Earth has one big ocean with many features.
2. The ocean and life in the ocean shape the features of Earth.
3. The ocean is a major influence on weather and climate.
4. The ocean makes Earth habitable.
5. The ocean supports a great diversity of life and ecosystems.
6. The ocean and humans are inextricably linked.
7. The ocean is largely unexplored.

Species Spotlight: Ceratium furca

Found solitary or in pairs, Ceratium furca is a dinoflagellate characteristically found worldwide in temperate and tropical waters. Ranging in size from 70-200 μm long and 30-50 μm wide, C. furca's body is straight and triangular in shape with an epitheca that tapers gradually into three anterior horns, two of which are paired. If viewed from its backside, C. furca is distinctively concave in shape.

Like many dinoflagellates, C. furca reproduces asexually and obtains energy through photosynthetic pathways utilizing light from the sun. However, under adverse conditions C. furca is known to reproduce sexually and obtain energy through phagocytosis, ingesting external energy sources such as ciliates and tintinnids. This ability to obtain energy internally (photosynthesis) and externally (phagocytosis) is known as mixotrophy.

The entire genus of Ceratium is not known to produce toxins, however, blooms are contributing to ever-increasing ecological damage to coastal areas with serious impacts on the ecosystem. During large blooms, the three horns can cause damage to fish gills that eventually leads to large fish kills. Fish kills have also been a result of suff ocation induced by mucus production in C. furca that clogs the gills of fish. Interestingly, the decay of a red tide of C. furca caused large marine mortalities in March 1994 in St. Helena Bay on the South African west coast, a result of hydrogen sulphide poisoning caused by anaerobic bacteria present in the absence of dissolved oxygen in the water.

species spotlight archive

Ask the Scientist: Are there any toxic freshwater species?

submitted by: Jordan Walton, Burke HS

Answer: Yes, there are freshwater algae that produce secondary metabolites (compounds not used in metabolic processes) that have toxic effects on humans and other animals. The phylum that contain these freshwater organisms are called cyanobacteria (or blue-green algae). The toxin concentrations produced by these organisms are normally very low and do not have an effect on us except in heavy bloom situations. The genuses that are known to be toxic include Aphanizomenon, Anabaena, and Lyngbya which produce neurotoxins. Liver toxin species include Microcystis, Cylindrospermopsis, Nodularia. Lyngbya may also produce compounds that can cause skin rashes. We still don't fully understand or know all the toxic organisms out there.

Wesley C. Jackson, Jr., MSc.
Ph.D. Student at the Medical University of South Carolina