A Guide for Teachers and Students

History: Queen conch are found in the Florida Keys, the Bahamas, Bermuda and throughout the Caribbean region. In the summer, planktonic conch larvae settle into shallow coastal habitats to graze amoung seagrass blades. Three years later, the animals reach maturity and lay egg masses in sandy, near-reef habitats.

Countless generations have relied on queen conch as a food source, tribal tool, sounding horn, building material, and decorative ornament. Fishing pressure has reduced natural populations of conch resulting in a moratorium on collection of queen conch in Florida since 1986. Quotas, size limits, and closed seasons have been implemented in many Caribbean countries.

Vocabulary:

    • 1. Fisheries species: An animal or plant harvested from the water (fresh or salt) and usually used for food.

    • 2. Queen conch: Stombus gigas. An important commercial and subsistence fisheries specie in Florida and throughout the Caribbean.

    • 3. Fisheries regulations: Series of rules designed to protect a fisheries species:
    a. Moratorium: A ban on the fishing or collection of a specie (Queen conch moratorium in Florida waters since 1986).
    b. Quota: Limit on the number of animals allowed to be harvested per day/week/season for each fisherman or country.
    c. Bag Limit: Limit on the number of animals collected per day
    d. Closed season: Amount of time a particular fishery is closed to fishermen. Usually occurs during the reproductive season.

    • 4. Convention of the International Trade of Endangered Species: CITES, regulation that helps protect a fishery by insuring that the animal is being harvested at a level consistent with its natural population growth. The queen conch was listed to Appendix II of CITES in 1992

    • 5. Mollusca: Phylum of animals that animals that consists of gastropods (with shells that twirl), bivalves (with shells that close), and cephalopods (octopus, squid, cuttlefish, and nautiluses).

    • 6. Siphonal length: The shell length of a conch as measured from the apex of the spire to the end of the siphonal canal.

    • 7. Calipers: Tool used for measuring siphonal length

    • 8. Plantotrophic larvae: Animals that ned to feed during their larval cycle versus lecitrophic larvae that do not.

    • 9. Veligers: Term used for larval conch.

    • 10. Aquaculture: The farming of marine and freshwater organisms for food, recreation, and research purposes.

Setting up Conch in the Classroom:

The first step in bringing conch into your classroom is to decide why. Do you want to run an experiment, observe their behavior, or just enjoy the sight of the animals. If you would like to run an experiment, you will need to establish which parameters you would like to test. Some of the scientists in the Conch Heritage Network have conducted research on density, feed types, and feed conversion ratios. The research you choose to do will determine what equipment is required, however, here is a list of some basic supplies that can be help you put conch in the classroom

Supplies:

    • 1. Aquarium (depending on your experiment, a 10 gallon aquarium (which can hold up to 10 conch) can be used for one replicate or divided in half or thirds if the space is limited)

    • 2. Under-gravel filter system with sand (1-3 mm diameter) or charcoal cartridge filter

    • 3. Air pump

    • 4. Water quality kit (temperature, salinity, pH, ammonia, and dissolved oxygen if available)

    • 5. Calipers

    • 6. Scale (if weighing the animals or food)

    • 7. Calculator

    • 8. Food

    • 9. Conch

    • 10. Salt water (Instant Ocean will work)

Water Quality:

The following is a guideline for your aquarium:

    • 1. Temperature: 68-93° F (20-33 °C), Optimal: 27-29 °C

    • 2. Salinity: 30-37 ppt, Optimal: 32-36ppt

    • 3. pH: 8.0-8.8, Optimal: 8.0-8.4

    • 4. Ammonia: 0.1-0.5 ppm

    • 5. Dissolved Oxygen: 5.0-8.0 ppm

Purchasing Conch and Conch Food:

You will need to determine the stocking density in the system: Other than the density experiment, we recommend a stocking density of 75 conch per sq. meter (8 conch per square foot). For one ten gallon aquarium (20" x 10.5" x 12") you would need 10 conch. The current price for conch and food is as follows:

CONCH • Varies - please contact Amber Shawl
FOOD • 1 lb juvenile food = $5.00 (tax exempt for schools)

Please contact Amber Shawl for initial purchasing requests:
Harbor Branch Ocenaographic Institution, 5600 US 1 North
Ft. Pierce, FL 34946
P: (772) 465.2400 (x578) • F: (772) 466.6590 • ashawl@hboi.edu

Suggested Experiments:

1. Density. -- The aquarium is divided into three parts or there are three aquariums for each density. The experiment should be run in triplicate for statistical purposes. The juvenile queen conch can be placed in varying densities and the students can observe their growth rate.

2. Substrate. -- Similar to the density experiment, the students can observe the effects of sand versus other substrates (pebbles, glass, plastic) on the shell growth of the juveniles.

3. Food Types. -- The juvenile queen conch can be fed several different types of food. The animals can be weighed at the beginning and end of the experiment, and the amount of food fed to the animals should be weighed daily. This way the students can determine the Feed Conversion Ratio (FCR) for the different types of food. If the length of the animals is measured as well (on a weekly basis) the students can compare the growth rates with the different diets. Contact the CHN headquarters for information about purchasing conch food.

4. Water quality parameters. -- The students can adjust the temperature or salinity in their aquariums and compare growth rates to those in a well-conditioned tank. You will need at least two aquariums for this.