2013
Artificial Habitats
Debanhi Jimenez
8°B Netherlands
01/11/2013
Index
Introduction
Methods
The “Animalization of Humankind”
Habitat Structures
Conclusion
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Introduction
Artificial habitats in marine ecosystems are employed on a limited basis to restore
degraded natural habitats and fisheries, and more extensively for a broader variety of
purposes including biological conservation and enhancement as well as social and
economic development. Included in the aims of human-made habitats classified as
artificial reefs are: Aquaculture/marine ranching; promotion of biodiversity; mitigation of
environmental damage; enhancement of recreational scuba diving; eco-tourism
development; expansion of recreational fishing; artisanal and commercial fisheries
production; protection of benthic habitats against illegal trawling; and research.
Structures often are fabricated according to anticipated physical influences or life history
requirements of individual species. For example, many of the world’s largest reefs have
been deployed as part of a national fisheries program in Japan, where large steel and
concrete frameworks have been carefully designed to withstand strong ocean currents. In
addition, the differing ecological needs of porgy and sea bass for shelter guided the design
of the Box Reef in Korea as a device to enhance productivity of marine ranching. The
effect of these and other structures on fisheries catch is positive. But caution must be
exercised to avoid using reefs simply as fishing devices to heavily exploit species attracted
to them. No worldwide database for artificial habitats exists.
The challenge to any ecological restoration effort is to define the condition or possibly
even the historic baseline to which the system will be restored; in other words, to answer
the question: “Restoration to what?” Examples of aquatic ecosystem restoration from
Hong Kong (fisheries), the Pacific Ocean (kelp beds), Chesapeake Bay (oysters) and the
Atlantic Ocean (coral reefs) are discussed. The degree to which these four situations
consider or can approach a baseline is indicated and compared (e.g., four plants per 100
m2 are proposed in one project). Measurement of performance is a key factor in
restoration planning. These situations also are considered for the ecosystem and fishery
contexts in which they are conducted. All use ecological data as a basis for physical design
of restoration structures. The use of experimental, pilot and modeling practices is
indicated.
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A context for the young field of marine restoration is provided by reviewing major factors
in ecosystem degradation, such as high stress on 70% of commercially valuable fishes
worldwide. Examples of habitat disruption include an extensive hypoxic/anoxic zone in the
Gulf of Mexico and nutrient and contaminant burdens in the North Sea. Principles of
ecological restoration are summarized, from planning through to evaluation. Alternate
approaches to facilitate ecological recovery include land-use and ecosystem management
and determining levels of human population, consumption and pollution.
It has long been known that greater numbers and kinds of fishes inhabit rocky coasts,
reefs, and banks than smooth, unbroken sandy or muddy bottoms, and that shipwrecks
provide excellent fishing in otherwise non-productive areas.
On this basis, various state and private agencies have placed old automobile bodies and
other objects in areas generally barren of sportfish. Reports have indicated greatly
increased sportfish yields in these areas, but to our knowledge, no full-scale scientific
evaluation of artificial reefs has been made. The Japanese have done some work in this
field, but their results are unpublished. With these facts in mind, the California
Department of Fish and Game instituted a study of artificial reefs in April 1958.
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FIGURE 1. Biologist-diver Jeremy C. Sexsmith studies encrusting organisms and fishes on a
shipwreck. Photograph by Charles H. Turner, August 1959.
Many flat, sandy or muddy areas occur along the southern California coast, often near
small-boat harbors. While large party, charter, and private boats can travel long distances
to offshore islands and productive headlands, these fishing grounds are beyond the range
of small-boat fishermen. The chief value of artificial reefs is to provide owners of small
boats with good fishing near a harbor (Carlisle 1962).
With California's population increasing at a tremendous rate each year and recreation
needs multiplying at an unprecedented pace, coastal fishing assumes an ever more
important role. Pollution of these same waters, especially by industrial wastes, is
constantly decreasing the yield of once productive areas. Kelp beds, of great importance
in the ecology of the region, have diminished or virtually disappeared in the path of these
pollutants, with consequent decreases in suitable fish habitat.
In addition, several successive years of above average water temperatures drastically
reduced vast areas of kelp beds along our shores. Sea urchin predation on the reduced
beds has been widely observed by divers.
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FIGURE
2. Sea
urchins, starfish, and gorgonians on devastated portion of kelp bed. Photograph by
Charles H. Turner, September 1960.
To determine the true value of artificial reefs, we carried out routine diving so we could
observe and obtain as much information as possible on the numbers and kinds of fishes
occurring around artificial habitat (Figures and). Kelp growth, numbers and species of
invertebrates, animal behavior, and many other observations also have been made.
The theory of attraction of fishes to solid objects (thigmotropism) is discussed by Breder
and Nigrelli (1938), and probably explains some of the success of artificial reefs in
attracting and holding fishes. Observations made during the Department's Kelp
Investigations Program at Scripps Institution of Oceanography (Quarterly Progress
Reports), and our observations of fishes following a young giant kelp plant, Macrocystis
pyrifera, drifting across a semi-barren sand bottom, and of fishes attracted to artificial
reefs and offshore oil installations definitely support this theory.
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Breder and
(1938)
Nigrelli
described
thigmotropism as the "desire" of fishes to be close to a solid object. The attraction of
fishes to each other (schooling behavior) also becomes a necessary explanation of reef
success. Finally, availability of shelter and food help explain the attractiveness of artificial
habitat.
As part of our investigation of man-made marine environment, we also undertook a study
to evaluate the effects of offshore oil drilling installations.
FIGURE 3. Biologist-divers Jeremy C. Sexsmith (left) and Charles H. Turner descend for
diving observations. Photograph by John G. Carlisle, Jr., 1958.
FIGURE 4.
divers
Turner
John G.
take
record data
installed
reef.
by Gene
1958.
BiologistCharles H.
(left) and
Carlisle, Jr.
photos and
on newly
artificial
Photograph
Daniels,
METHODS
Selecting
Reef Sites
Artificial
reef sites
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were selected in flat, sandy areas where fishing for semi-resident sportfishes such as kelp
bass, sand bass, and sheephead was generally poor. These species, abounding in rocky
areas and kelp beds, might be expected to associate with artificial reffs.
Depths between 50 and 60 feet are considered suitable for many fishes we hoped to
attract and these depths are also within the optimum range for giant kelp plants which
would further enhance the value of artificial habitat. Another important consideration is
that fairly prolonged diving surveys can be made at these depths without employing stage
decompression (stops of several minutes duration at specific depths, to allow release of
excess nitrogen from the diver's system). U.S. Navy Standard Air Decompression Tables
are followed in determining these diving limits. To disregard these decompression tables
can result in caisson disease (bends), a serious diving illness.
The “Animalization of Humankind”
A brave new world is rising, and with it the dehumanization of humanity is accelerating.
One reader of Huxley’s timeless 1931 book Brave New World describes the society of
Huxley’s future: “The pleasure-seeking society pursues no spiritual experiences or joys,
preferring carnal ones. The lack of a religion that seeks a true transcendental understanding
helps ensure that the masses of people, upper and lower classes, have no reason to rebel.”
Love and marriage are separated from reproduction in Huxley’s world. Babies are grown in
labs while the sterilized masses are encouraged to embrace promiscuity.
In our present world, projections from Deutsche bank state that due to falling fertility rates,
“…the human race will no longer be replacing itself by the early 2020s.” Sperm counts are
also falling world-wide. Following these trends is what some call the “animalization” of
humankind through the increasing prevalence of porn. Brave New World is no longer
science fiction.
Roger Howard writes in the Futurist magazine,
“…the animalization of humankind will inevitably have consequences that stretch well
beyond the screens upon which we view internet porn. Not only will those who participate
in online action be labeled with such terms, but those labels will shape how we see each
other. If each of us increasingly sees others more as “animal” than “human,” then it follows
that our mutual respect is similarly eroded. Human well-being is traditionally protected by a
framework of morals and manners that simply does not protect animals… and human life is
sacred in a way that animal life is not.”
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Habitat Structures
The artificial habitat structures outlined below represent truly remarkable innovations. The
space-age material used allows for ease of contruction and installation and provides a
remarkably long, useful life. With life estimates ranging from 30-50 years, the cost
effetiveness of these structures far surpasses that for conventional structures such as brush
piles, etc. Developed and constructed to provide specific habitat needs for targeted fish
species, these structures help bring warmwater fisheries management into the 21st century.
Anglers United is proud of the role we played in contributing to the develpment and testing
of these structures. For more information concerning the availability, cost, or other
information about these habitat structures, or the possibility of finanacial assistance for
habitat projects, contact Anglers United. for contact information.
FISH-N-TREE
Purpose: The broad leaves of the Fish-N-Tree provide
excellent overhead cover for various fish. The Fish-N-Tree has
been found extremely successful, especially when eight to
twelve have been “planted” together to form a Fish-N -Forest.
Forests are placed near natural weedbeds, Crappie Condos,
Bass Bungalows, brush piles, droppoffs, and ledges.
Description: A plastic Fish-N-Tree unti consists of a threefoot stalk with six leaves. They are modular and can be
connected to form trees of any length. Stalks from three to
twenty-seven feet long have been used. Anchoring can be
achieved using duck bill earth anchors, cement blocks, or other heavy objects.
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http://link.springer.com/article/10.1007%2Fs10750-006-0457-9?LI=true
http://content.cdlib.org/view?docId=kt929006q1&doc.view=entire_text
http://www.infowars.com/the-artificial-habitat-for-mankind-this-isnt-the-end-of-theroad/
http://www.anglersunited.org/habitat_structures.html
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Conclusion
I think that the artificial habitats are in some ways good and in some ways bad. Because
you can help the extending animals but you intervene in the habitat that’s why a lot of
animals are disappearing.
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