Overview
Download PDF of this PageThis goal assesses the
ability of regions to maximize the sustainable harvest of non-food living marine resources. It does not include bioprospecting, whose potential is largely unknowable, or mineral products such as oil and gas or mining products which cannot be considered sustainable in the absence of appropriate limits on their extraction.
The
Ocean Health Index measured six commodities to calculate Status and Trend for the
Natural Products goal. They were: Ornamental Fish, Seaweed and
Plants, Sponges, Shells, Fish Oil, and Coral. These are the only products for which global databases exist.
Other natural products may be harvested in some countries, but since they are not harvested everywhere, they could not be included in the global assessment. Such products could be included in a regional assessment.
Scroll down the page to see descriptions of each category and how it was measured.
How Was It Measured?
Imagine the difficulty of describing and distinguishing
all of the world’s products for record keeping, taxes, tariffs, monitoring
controlled goods, trade statistics and other purposes! The World Customs Organization (WCO) does
that by assigning a unique six digit code to more than 5,000 commodity groups
as part of the Harmonized Commodity Description and Coding System ("Harmonized
System" or simply "HS"). HS, which is updated about every 5
years, captures over 98 percent of the merchandise in international trade.
HS is linked with the International Standard
Statistical Classification of Fishery Commodities (ISSCFC), which the UN Food
and Agriculture Organization (FAO) uses to categorize its marine data. ISSCFC covers products derived from fish,
crustaceans, molluscs and other aquatic animals, plants and residues caught for
commercial, industrial or subsistence uses, by all types of fishing units
operating in all aquatic environments, in inshore, offshore or high seas
fishing. Commodities produced from the raw materials supplied by all kinds of
aquaculture are also included. Data for
the six non-food marine commodities assessed in the Natural Products goal are
obtained from the FAO database and used to evaluate how how sustainably countries harvest those resources.
The Ocean Health Index used FishstatJ 2.0.0 to obtain FAO data on the export amount (metric tons) and monetary value (US
dollars) for each of the six types of products evaluated. In any years when a country reported either export value or tonnage for a product but not both, the missing amount
was gap-filled using a smoothed linear relationship between amounts and value
for this product-region through time.
The
reference point for harvest of each product in each region is its peak export
across all years. Sustainability of that peak is unknown so a (presumably sustainable) reference point
is defined at 35% below the peak. That value is set at 1.0 and all lower values
are rescaled to it. Products never
harvested in a region are excluded.
Status for
the goal is the geometric average of the relative contribution of each product multiplied
by its sustainability factor. The relative contribution of each product to a region's status score for Natural Products is calculated as the
maximum US dollar value for that product (from the smoothed, gap-filled data)
across all years of data divided by the sum of maximum values for all products
harvested in the country.
Sustainability for habitat-based harvest is determined
by ‘Exposure’ and, where applicable, ‘Risk.’ A product’s sustainability is (1- Exposure) if
it has no risk factor; or (1 – [Exposure + Risk]) ÷ 2 if it does.
Exposure. Exposure is calculated as the (log-transformed)
intensity of harvest per km2, relative to the global maximum.
Risk. For
all corals, risk is set at 1 since species in both subclasses and multiple
orders are listed in CITES Appendices II and III. Risks for sponges, algae or marine
plants and shells were set at 0, because none are listed in CITES except for giant
clams (Tridacnidae spp.) and date clams (Lithophaga lithophaga) (CITES Appendix II). Risk for ornamental fish was set based on
assessments of cyanide or dynamite fishing by Reefs at Risk Revisited assuming that most ornamental
fishes are harvested from coral reefs.
To calculate sustainability for Fish Oil, each fish
stock is assigned an exploitation status based on its biomass relative to its
calculated biomass at maximum sustainable yield (B/BMSY) and multiplied by a
penalty factor when B deviates from BMSY by more than 5%. Overharvesting is penalized by successively greater penalties the smaller B is relative to BMSY. Underharvesting is also penalized when B > BMSY, but only half as severely as overharvesting. The sustainability of
a country’s Fish Oil exports is expressed as the yield-weighted sustainability of
its fishery stocks. See Fisheries: Status for details on how stock status is calculated.
For overall score calculation, Trend is the
slope of the Status scores for each product for the previous five years; and a
unique Pressure and Resilience score is calculated for each product.
Scroll down to get further information on each Natural Product that was assessed, including the HS/FAO categories used for each.
Ornamental Fish
'Ornamental
fish’ are species harvested and marketed for use primarily in home aquariums,
but also in commercial aquariums. Every
year, more than one billion ornamental fish are traded globally, 15 to 20
million of which are members of marine species (Weiner 2005). The number of
marine species traded has been estimated at between 1,400 and 8,000, most of
which are wild caught, unlike traded freshwater fish species, 90% of which are
farmed (FAO 2005-2012; Whittington 2007).
How Was It Measured?
Export
data are drawn from the Food and Agriculture Organization of the United
Nations (FAO) Global Commodities database for the most recent years available for ornamental fish. Data for the subcategories ‘Fish for
culture including ova, fingerlings, etc.’ and ‘Ornamental freshwater fish’ are excluded. The two categories used are “Ornamental Salt Water Fish” and
“Ornamental Fish Not Elsewhere Indicated (NEI).” For the
monetary value data, nominal dollars ("observed measure unit - US
Dollar"), as reported by the FAO, were converted into constant 2008 USD
using CPI adjustment data (Sahr 2011).
What Are The Impacts?
ECOLOGICAL IMPACT
Ornamental
fish that are traded on a global basis can introduce pathogens to a new
environment. Contact with wild populations could be harmful if native species
have no resistance to the foreign disease.
The
unsustainable harvest of ornamental fish can lead to habitat and/or ecosystem
damage (e.g., coral reefs) if fish species are over-harvested or if destructive
methods are used to collect them (e.g., cyanide, blast fishing).
Cultivation of some species, such as clownfish, has produced spectacular new color patterns and could reduce the demand for wild specimens and aquarium fishing pressure on reefs.
HUMAN HEALTH IMPACT
No
direct impacts known. Unsustainable fishing methods, such as use of dynamite or cyanide, could reduce reef health and food fish supply for local populations.
ECONOMIC IMPACT
The
market for ornamental reef fish and coral has increased by 12-13% annually, and
the US comprises 80% of the importing market (Weiner 2005).
Two
thirds of ornamental fish exports are derived from developing countries where
fisheries often have an important economic role. However, certain fish stocks
are often depleted due to overfishing and/or growing human population needs.
Efforts are currently being made to minimize the harmful impacts of harvesting,
as well as to replace wild caught species with farmed fish.
Ornamental specimens for aquariums are expensive, often costing
10 times or even 100 times as much as comparable organisms used for food or
other purposes. For example, in 2000,
one kilogram of aquarium fish from the Maldives was valued at nearly US $500,
compared to only US $6 for one kilogram of reef fish harvested for food
(Wabnitz et
al. 2003).
The high
value of ornamental specimens translates into significant revenue for exporting
countries. For example, approximately
50,000 people in Sri Lanka are directly involved in the export of marine
ornamental reef fish to 52 countries, earning the country approximately US $5.6
million per year (Wabnitz et al. 2003).
Seaweed and Plants
Various
brown, green and red algae as well other marine plants are used to make
stabilizers and thickeners for foods, cosmetics and industrial products as well
as nutritional supplements and condiments. Seaweeds
and other marine algae can be harvested in their natural habitat or cultivated
in coastal waters or in tanks on land.
In
the mid 1980s, seaweed farming became increasingly popular (vs. harvest from
wild stocks) due to a significant rise in demand (Crawford
2002).
How Was It Measured?
Information used by the
Ocean Health Index to determine harvest and value for seaweed and plants is
from the Food and Agriculture Organization of the United Nations (FAO) Global
Commodities Database, which contains data on exports of
natural products by each country. The most recent data available are used.
Data categories used were: Agar
agar in blocks, Agar agar in powder, Agar agar in strips, Agar agar nei,
Carrageen (Chondrus crispus),
Green laver, Hizikia fusiforme (brown
algae), Kelp, Kelp meal, Laver dry, Laver nei, Laver smoked, Other brown algae (Laminaria,
Eisenia/ Ecklonia), Other edible seaweeds, Other green
algae (Ulva, Enteromorpha),
Other inedible seaweeds, Other red algae, Other seaweeds and aquatic plants and
products thereof, Rock laver, and Undaria
pinnafitida (brown algae).
Sustainability of the harvest was
measured as the intensity of harvest per km2 of a country’s potentially
harvestable habitat. Exposure values were rescaled to
between 0-1 using the global maximum intensity of harvest as the maximum value
and 0 as the minimum value.
For
the monetary value data, nominal dollars as reported by FAO ("observed
measure unit - US Dollar") were converted into constant 2008 USD using CPI
adjustment data (Sahr 2011).
What Are The Impacts?
ECOLOGICAL IMPACT
Wild seaweeds and other marine plants provide shelter and food for many species, so intensive
harvest can damage intertidal habitats if not properly
managed.
The methods used to cultivate seaweed
are relatively low impact, especially if they are done off-bottom.
Seaweed cultivation can have a
positive effect on fisheries by increasing local populations of herbivorous
fish. However, it can have a negative impact on neighboring ecosystems (e.g.
mangroves, coral reefs) by altering water flow and depleting nutrient sources.
HUMAN HEALTH IMPACT
Seaweeds
and other marine algae are used as additives in animal feed, compost and
fertilizer, and as stabilizers, thickeners, emulsifiers, and supplements for
nutritional health or taste enhancement in food for human consumption (e.g. ice cream,
yogurt, mayonnaise). They are also used in cosmetics, toothpaste and other body
products.
ECONOMIC IMPACT
The
genus Porphyra includes approximately
70 species of intertidal red algae
used for human food or nutritional supplement and may be the most harvested and
cultivated type of seaweed worldwide. In
Japan alone, the cultivation of Porphyra
is said to be worth US $1 billion each year (Blouin et al. 2010).
Sponges
Sponges are primarily harvested for use as bath sponges. Some are also
used medically, to dress wounds, as contraceptives or to absorb menstrual flow. Chemical compounds found in marine sponges, probably made by the bacteria that inhabit their tissues, have provided important medicines for cancer, HIV/AIDS and other illnesses.
Sponges
are a diverse aquatic invertebrate phylum, with over 7000 living species found
in a wide range of marine environments. A few species (~150) live in
freshwater and brackish water, but the vast majority are marine, with different
species found from tropical coral reefs to arctic waters, and from coastal,
shallow waters to the deepest parts of the ocean (Lavrov 2009; Hogg et al.
2010).
Sponges are essential components
for a healthy ecosystem in terms of their high biomass and water filtration and
nitrification abilities. They also contribute to the biodiversity of habitats
by providing shelter and breeding grounds for numerous marine species and
microorganisms.
Although
the increased use of artificial sponges has led to a significant decrease in
commercial fishing for sponges, overfishing, disease and rising sea
temperatures have all contributed to declines in local sponge populations over
the past century.
How Was It Measured?
The
Ocean Health Index measurements are based on data for the number of tons of
sponges exported on a per country basis. The intensity of harvest per
km2 of potential habitat for a country was determined according to export
data (1976-2008) from the FAO Global Commodities database using the categories Natural
Sponges Not Elsewhere Indicated (nei), Natural Sponges other than raw, Natural
Sponges raw, and coral and rocky reef extent data from Halpern
et al. 2008.
For the monetary value data, nominal
dollars ("observed measure unit - US Dollar"), as reported by the
Food and Agriculture Organization of the United Nations (FAO), were converted
into constant 2008 USD using CPI adjustment data (Sahr 2011).
What Are The Impacts?
ECOLOGICAL IMPACT
Bottom trawling fishing
methods damage or destroy sponge habitats and result in large amounts of
bycatch.
Sponges provide shelter, structural habitat, and water filtration for numerous species.
Deep sea sponge communities
are not harvested commercially and are not included in the Ocean Health Index
since global data are not available. Deep sea sponge communities are
susceptible to damage by deep sea fish trawling. These communities are oases of
biodiversity and shelter large populations of fish that are of commercial
interest, but that are difficult to harvest sustainably, because the sponges and cold water corals that form their intricate architecture are very fragile, slow growing and may
take a century or more to recover from damage (Hogg et al. 2010).
HUMAN HEALTH IMPACT
Marine sponges yield many chemical compounds that are being used or tested to treat cancer, HIV/AIDS and as antibiotics. Many of the compounds appear to be produced by bacteria that live within the sponges' tissues.
ECONOMIC IMPACT
The
most commercially important sponges are those that consist of soft fibers of
spongin protein (Demospongeae). Overfishing has depleted populations of soft
sponges and prices have increased substantially. As a result, commercial sponge fishing has
suffered as more affordable synthetic substitutes now dominate the market for
human use.
Shells
‘Seashells’ are the hard outer casings (exoskeletons) made by marine animals for the protection and support of
internal organs. Although a number of marine groups, including Crustaceans
(e.g. crabs, lobsters), Echinoderms (e.g. starfish, sea urchins), Polychaete
worms, and others make exoskeletons, the term seashell typically refers to the
shells produced by marine Molluscs (e.g. clams, mussels, snails, conchs etc.);
this is how the term was used in the Ocean Health Index.
Seashells have been traded and collected for
centuries for use in jewelry, decoration, religious ceremonies, and currency.
Today, trade in shells, pearls, and shell products remain an important part of
many local economies.
How Was It Measured?
The
Ocean Health Index measured the harvest of shells in terms of tons exported per
country according to the Food and Agriculture Organization of the United
Nations (FAO) Global Commodities database (1976-2010), using the listings for
Miscellaneous Corals and Shells, Abalone Shells, Mother of Pearl shells, Oyster
shells, Sea snail shells, Trochus shells and ‘Shells not otherwise listed’.
The intensity of harvesting (exposure) was
calculated as tons exported per km2 of potential habitat. Potential
habitat was estimated as area of coral reef and rocky reef using data from Halpern
et al. (2008). Exposure values were rescaled to between 0-1 using the global
maximum intensity of harvest as the maximum value and 0 as the minimum value.
For
the monetary value data, nominal dollars, as reported by FAO ("observed
measure unit - US Dollar"), were converted into constant 2008 USD using
CPI adjustment data (Sahr 2011).
What Are The Impacts?
ECOLOGICAL IMPACT
The shells of living and/or dead mollusks provide
habitats for plants, invertebrates, small fish, and crustaceans (e.g. Hermit Crab). Vital habitats can be destroyed when disturbed by harvesters and/or
collectors in search of shell species.
Populations of some important shell species are in
decline in certain areas, due to anthropogenic pressures such as overfishing,
habitat destruction, and pollution.
Shells and shell fragments are an important
component of some sandy beaches.
HUMAN HEALTH IMPACT
Certain species of molluscs that are prized for
their shells can also produce clinically important toxins that are harvested
for medicinal use (e.g. Cone Snail).
ECONOMIC IMPACT
The harvest of shell species, and the subsequent
transformation into craftwork for the shell trade, provides a significant
source of jobs and livelihoods for coastal communities, particularly in
developing countries.
Fish Oil
Fish oil is a product of the fishing industry that is most commonly derived from
small, pelagic species of fish that have low market value for direct
consumption (e.g. anchovies, herring, sardines) (Tacon 2006). The oil can be
produced either from the whole fish or from its liver, and it is most often
sold as an ingredient for aquaculture feed, but is also used for human dietary
supplements.
The
fish species that are used to produce fish oil are primarily wild-caught, and
in many cases their stocks are being depleted due to unsustainable fishing
practices. Countries do not specify the species they use to produce fish oil, so sustainability is estimated based on the overall stock status for the species harvested in each country, as detailed above in the main 'How Was It Measured?' section.
Rising costs for fish, energy, fish processing and fishery
resources have led to a decrease in the amount of
fish oil and fishmeal used worldwide. As a result, some nations are currently
exploring alternate methods of producing fish oil, which include utilizing
krill populations. Since krill themselves are a primary food source for many
marine species, depleting their populations could affect ecosystem and food web
structure. Certain types of algae, yeast and plants are also being considered
as alternative sources for human dietary supplements and for possible for use
as aquaculture feed.
Total
production of fish oil in 2006 was 0.943 million tonnes, of which 88.5% was
used as an additive to industrially compounded feed for aquaculture of shrimp
and fish (FAO, cited in Tacon and Metian 2008).
How Was It Measured?
Data
were drawn from the United
Nations Food and Agriculture Organization (FAO) Global
Commodities database for 1976-2010, using the following categories: Alaska
pollock oil nei, Anchoveta oil, Capelin oil, Clupeoid oils nei, Cod liver oil,
Fish body oils nei, Fish liver oils nei, Gadoid liver oils nei, Hake liver oil,
Halibuts liver oils, Herring oil, Jack mackerel oil, Menhaden oil, Pilchard
oil, Redfish oil, Sardine oil, Shark liver oil, Shark oil, Squid oil.
The
Status of fish oil production was calculated as the current harvest level
relative to its (buffered) peak reference point, multiplied by the
sustainability of the harvest.
To calculate sustainability for Fish Oil, each fish stock is assigned an exploitation status based on its biomass relative to its calculated biomass at maximum sustainable yield (B/BMSY) and multiplied by a penalty factor when B deviates from BMSY by more than 5%. Overharvesting is penalized by successively greater penalties the smaller B is relative to BMSY. Underharvesting is also penalized when B > BMSY, but only half as severely as overharvesting. The sustainability of a country’s Fish Oil exports is expressed as the yield-weighted sustainability of its fishery stocks. See Fisheries: Status for details on how stock status is calculated.
Trend was calculated as the change of Status
over the five most recent years of data.
What Are The Impacts?
ECOLOGICAL IMPACT
The
fish species that are used to produce fish oil are primarily wild-caught, and
in many cases their stocks are being depleted due to unsustainable fishing
practices. As these small, pelagic species tend to be a primary food source for
many marine species, depleting their populations could affect ecosystem and
food web structure.
HUMAN HEALTH IMPACT
Fish
oil is often used as a human dietary supplement because the oil derived from
certain species tend to be rich in omega-3 fatty acids, which are believed by
many to promote a healthy cardio-vascular system. These cardiovascular
benefits are attributed to the fact that the presence of omega-3s in the blood
inhibits the formation of blood clots and reduces inflammation in the blood
vessels.
These supplements should be taken with doctor’s
approval and may have side effects.
ECONOMIC IMPACT
The
fact that costs for fish, energy, fish processing and fishery resources are
continuing to rise has led to a decrease in the amount of fish oil and fishmeal
used worldwide.
Corals
The corals assessed in the Natural Products goal all come from tropical coral reefs, which live in warm, clear water at relatively shallow depths. ‘Hard’ corals use calcium carbonate from seawater to synthesize a hard, mineral protective shell around each polyp. These exoskeletons, along with shells formed by coralline algae, mollusks and tubeworms, spicules made by sponges, and shells of other calcifying species form the structural foundation of coral reefs. Corals catch plankton with their tentacles, but most of their nutrition comes from photosynthetic algae that live in their tissues, using the coral’s waste products for their own nutrition and feeding the corals with sugars and other nutritious compounds that leak through their cell membranes.
When healthy, these reefs are intricately patterned carpets of life containing countless nooks and crannies inhabited by representatives of nearly every major taxonomic group. These tightly integrated systems providing food and shelter to a spectacular variety of fish and invertebrate species, including many of commercial value.
How Was It Measured?
Most of the trade in corals is classified under ISSCFC codes 291.1.5.10, ‘Coral and the like’ and 291.1.5.90, ‘Miscellaneous corals and shells.’ Explanatory HS notes define coral is the calcareous skeleton of a marine polyp that is generally used for articles of jewelry and indicated that the category includes coral that is ‘unworked’ (that is, only the outer crust has been removed) or ‘simply prepared’ (that is, not having undergone processes extending beyond simple cutting). This category does not include live corals exported for aquarium use and, in fact, no data on that trade are available.
What Are The Impacts?
Ecological Impact
Overharvesting for coral as a natural product probably may not be extensive enough to destroy reef structure, but can harm target species.
Populations of rare precious corals used for jewelry, such as black coral, gold coral and red coral, can easily be extirpated by overharvesting, especially because most grow very slowly.
Coral reefs are affected by many other pressures, including rising sea temperature, ocean acidification (lowered pH), destructive fishing practices (dynamite and cyanide), breakage by natural causes (hurricanes) or carelessness (boat anchors, trampling by snorkelers), pollution and sedimentation.
Human Health Impact
Harvesting coral for Natural Product purposes may not be sufficiently extensive to impact human health. The products made from coral are mainly ornamental.
Economic Impact
The very high economic value of tropical coral reefs derives from their environmental services, primarily food production, coastal protection and biodiversity. The economic benefit from coral harvests for jewelry or other Natural Products use is comparatively small, though it may be locally important. Such harvests are not likely to reduce the ability of tropical coral reefs to deliver ecosystem services, though they have the potential to decrease biodiversity locally.
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