Group Title: Environmental teaching plans
Title: What's at the bottom of a bay?
ALL VOLUMES CITATION PDF VIEWER THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/CA01300920/00040
 Material Information
Title: What's at the bottom of a bay?
Series Title: Environmental teaching plans
Physical Description: Archival
Language: English
Creator: St. Croix Environmental Education Team
Publisher: Division of Fish and Wildlife
Place of Publication: Frederiksted, VI
 Record Information
Bibliographic ID: CA01300920
Volume ID: VID00040
Source Institution: University of the Virgin Islands
Holding Location: University of the Virgin Islands
Rights Management: All rights reserved by the source institution and holding location.

Downloads

This item has the following downloads:

00040BottomofaBay ( PDF )


Full Text







E.T A LOCAL WAY OF LEARNING


Title:

Author:


Grade Level:

Concepts:
2. Ecosystem
9. Change


WHAT'S AT THE BOTTOM OF A BAY?

Eulalie R. Rivera Elementary School
Environmental Education Team


3-5


Disciplines:
1.Language Arts
2.Science


Objective:

Students will become familiar with the basic components of a bay marine
ecosystem by the completion of the word puzzle.

Rationale:

The challenge of a word puzzle in language arts can supplement the science
approach to marine plant life in the bays of the Virgin Islands.

Directions:

1. Distribute the activity sheet, allow 10 minutes for completion.

2. Discuss or- distribute the DCCA Fact Sheet No. 9, and have students check
their words for the correct answer to the activity question.

3. Discuss or have students write a short paragraph on the general value of
sea grasses to a marine ecosystem.


Resources:

Coastal Habitats. Grass Beds, DCCA Environmental Fact Sheet No. 9.


E-40














KEY



WHAT'S AT THE BOTTOM OF A BAY?

The statements below are clues or definitions for the words you must identify in
order to solve the word puzzle. This will answer the question "What's at the
bottom of a bay?"



1.One of the types of soil in a bay or beach, sometimes used for masonry.

2.A chemical component that- all living things need.

3.One of the types of marine plants sometimes found in a bay.

4.A word that describes animals or sea creatures feeding on green plants.

5.A name for a very common type of marine plant, as well as that of a sea
creature.

6.One of the fairly abundant/common types of marine plants.



7.A word that means keeping things the same; under control.


8. A word that is the opposite of to save or conserve.

Key


E.T.


E-40











E-40


Name:
School:
WHAT'S AT THE BOTTOM OF A BAY?

The statements below are clues or definitions for the words you must identify
in order to solve the word puzzle. This will answer the question "What's at
the bottom of a bay?"



1.One of the types of soil in a bay or beach, sometimes used for masonry.

2.A chemical component that all living things need.

3.One of the types of marine plants sometimes found in a bay.

4.A word that describes animals or sea creatures feeding on green plants.

5.A name for a very common type of marine plant, as well as that of a sea
creature.

6.One of the fairly abundant/common types of marine plants.

7.A word that means keeping things the same; under control.

8. A word that is the opposite of to save or conserve.



















What Lives There?

These areas are not really barren. They usually support scattered algae (marine
plants) and the flowering plant Halophila. Occasional sponges and small solitary
corals are present, especially where there is some solid object -- usually a
piece of debris -- for attachment. Bottom fishes are few, but lizard fish and
file fish are not uncommon. Conch, especially the small fighting conch, and
hermit crabs may sometimes be numerous. The preponderance of animals in this
habitat is infauna-- burrowing or tube dwelling forms in the sand. Among the
most numerous are several kinds of worms which may occur in densely packed beds.
A large variety of mollusks, crabs and shrimp live in the sand. Many are
nocturnal feeders and when they emerge at night, fish, lobsters, rays, sharks,
and other predators from adjacent areas move in to feed on them.


Major Attributes


Use Limitations


These large
good source
materials.


sand deposits may be a
of sand for construction


These areas are relatively
tolerant of development and
human activities.


Island Resources Foundation, V.I. Marine Environments, VICZM Program, Tech.
Supplement No. 1, 1976.

(Editor: Marsha McLaughlin, Policy and Planning Unit, DCCA). Further info:
Environmental Specialist, DCZM).


E.T.


E-40











What Happens There ?


Marine pastures produce a significant amount, perhaps most, of the
oxygen generated in local inshore waters. On a bright day, dissolved oxygen
over a healthy grass. Bed will exceed the saturation value (i. e. the water
becomes supersaturated), and small bubbles rise from the leaves to the
surface.

Several species of small fish live in the pastures and a larger
variety of others come here to feed on the plants and myriad creatures that
live here. This is the habitat of the queen conch and feeding, grounds of the
sea turtles. A diverse group of animals live in the sand between the plants,
and the bottom is often heaped into mounds marking the burrow entrances of
large worms and shrimp.

There is a very close knit relationship between the plants and
animals in this habitat, both spatially and physiologically. The pasture is a
low profile environment. The plants usually do not exceed eight inches in
height, and all but a few of the associated animals live within this zone or
in the sediment. Thus, except for visiting foragers and predators, the majority
of community energy cycling goes on in close quarters. Wastes from the animals
are utilized by the plants which produce oxygen and forage. Mild enrichments of
t@ water as by small continuous sewage discharges can cause affected areas of
grass to grow extremely rapidly and produce long leaves. Prolonged enrichment
usually encourages a typical species of algae, indicative of pollution.

Grass beds help to stabilize the sand, and where they front a beach
it has been postulated that they act as a "footing" to retard seaward loss of
sand from the beach.

For unexplained reasons, patches of grass removed by various means
(dredging, boat anchors) may not be replaced for years. In most bays which
have been dredged, the marine pasture has not become re-established in the
dredged areas for many years. In the case of Lindberg Bay, St. Thomas 40
years have elapsed, -and a barren hole remains off the western portion of the
beach. Even small swatches cut by an anchor, a dredge, or a boat's propeller
may remain bare for a year or longer.



Major Attributes Use Limitations
High oxygen and biological Once destroyed, marine pastures
productivity, usually require a long time to recover Deep
holes may never recover. Anchoring, and
dredging should be avoided
Usually are associated with clear Since the community is dominated by plants,
water, but can tolerate some a certain minimum amount of light is
increased turbidity needed. Can't tolerate heavy turbidity.
Associated animals can remove silt
from periodic flooding, incorporate
it in sediment and "cleanse" the
bottom.Some ability to assimilate
other wastes stabilizes sandy bottoms
and absorbs wave energy.
Protects beaches.


E-40











DCCA ENVIRONMENTAL FACT SHEET NO. 9
COASTAL HABITATS: GRASS BEDS




What Are They?

Grass beds are frequently referred to as marine pastures or meadows.
This is because they areas of think growth of sea grasses and algae resembling
pastures on land and serving essentially the same purpose. Most inshore (near
to shore) bay bottoms are covered with such pastures, as are some extensive
areas outside of bays.

The location of grassbeds is controlled by a number of factors
including the character and stability of the bottom, depth, water clarity,
currents, and grazing by herbivores. Grasses prefer sand bottoms to hard ones,
but do not do well in areas of high wave energy where sand movement is great.
Their growth is also interrupted in channels or other areas with swift current.
Since the grasses require a lot of light, they usually do not grow below 60-70
feet deep. There is usually a band of bare sand between grass beds and a
coral reef or rubble pile. This is because the fish and sea urchins that live
there forage on the edge of the pasture.


The dominant plant in local marine pastures is turtle grass. The second
most abundant is manatee grass, a grass with thin cylindrical blades. A third,
less frequently encountered grass, is called shoal grass or eel grass. On some
shallow banks with fine sand, shoal grass may form large beds, as on the south
coast of St. Croix. The three plants are usually referred to as sea grasses.
They are unlike the majority of marine plants, which are algae, in that they are
true flowering plants. Annually, they produce flowers and seeds.




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs