Category Archives: Ocean Sustainability

5.4 The Precautionary Principle

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This is a realistic tool in our Choice of Futures.

Item 6 of The Earth Charter recognizes the importance of “preventing harm as the best method of environmental protection and when knowledge is limited, and applying a precautionary principle. (reference in the Earth Charter:).

Daily, individuals and governments are faced with making decisions for which there is very little research to support that human modification of an ecosystem can proceed witout a negative effect. In the past, in a drive to maximize economic profits, a decision would be made without knowing the effects on ecosystems or balancing economic profits with environmental profits. Now it is recognized that if there is any doubt about the outcome for the ecosystem, the project should not proceed.

If a marina is to be built in an intertidal mudflat, and if no studies have been done that would show the environmental impact, and the steps necessary to mitigate this projected impact, then decisions on such a project would be put on hold until the science is available.

The FAO has summarized its recommendations on this subject in its report: FAO Technical Guidelines for Responsible Fisheries – Precautionary Approach to Capture Fisheries and Species Introductions – http://www.fao.org/docrep/003/w3592e/w3592e00.htm

Fisheries Management, fisheries research , fisheries technology and species Introductions are all examined from the point of view of the Precautionary Approach.

In the reference below, three examples in relation to fisheries are discussed :

THE PRECAUTIONARY PRINCIPLE..MAKING IT WORK FOR FISH AND FISHERMEN
By Molly Thomas and Zeke Grader http://www.pcffa.org/fn-jun00.htm

  • “The first is habitat. With salmon and a number of other commercially-valuable fish stocks, particularly those that are riparian or wetland dependent, merely restricting harvest on a precautionary approach may do little to help stocks unless there is a concomitant use of the principle for the protection of habitat.
  • The second area where the precautionary approach is needed now is with aquaculture. Pollution, nutrient loading, habitat destruction (e.g., mangrove deforestation in shrimp aquaculture), spread of disease, and escaped fish into the wild are all prevalent problems in many forms of aquaculture
  • Third, the precautionary principle has to be applied to genetically-engineered fish or “GMOs” (genetically modified organisms).

The precautionary principle is really just about common sense. As individuals we use the precautionary principle in any situation that involves our own personal safety, at least most of the time. Usually, the ability to weigh these situations increases with age and experience. It is time in this society that we start to use our common sense a little bit more often. Who better to lead this movement than one of the oldest industries on the earth? We have seen it work in the past on discrete stocks of fish, maybe it is time that we insist that we use it universally.”

Other references on the Precationary Approach are included below:

A Canadian Perspective on the Precautionary Approach/Principle
http://www.ec.gc.ca/econom/pamphlet_e.htm

An Australian reference
http://jnevill.customer.netspace.net.au/Precautionary_principle.htm

The Precautionary Principle:
Where the possibility exists of serious or irreversible harm, lack of scientific certainty should not preclude cautious action by decision-makers to prevent such harm. Management needs to anticipate the possibility of ecological damage, rather than react to it as it occurs.
Jon Nevill                                                                                                                2004
There are many definitions of the precautionary principle.  They all have two key elements.  The first is an expression of a need by decision-makers to anticipate harm before it occurs. Within this element lies an implicit reversal of the onus of proof: under the precautionary approach it is the responsibility of an activity proponent to establish that the proposed activity will not result in significant harm. The second key element is the establishment of an obligation, if the level of harm may be high, for cautious action to prevent such harm even in the absence of scientific certainty.
The precautionary principle rests on history and ethics rather than logic or science.  It incorporates the concept that a person or agency should take responsibility for unintentional damage which may (directly or indirectly) result from actions taken by this person or agency. It is also a principle based on experience.  According to Ludwig et al. 1993: “Although there is considerable variation in detail, there is remarkable consistency in the history of resource exploitation: resources are inevitably overexploited, often to the point of collapse or extinction.”  Even though the medium and long-term costs far outweigh short-term benefits, resource over-exploitation continues today. The need for caution is a clear message from recent history (Harremoës et al. 2002).

http://www.ids.org.au/~cnevill/LawlinkNSWStein.htm

Are Decision-makers Too Cautious With The Precautionary Principle?

5.5 Ocean Food: whats in your diet?

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5.3 Fishing Down Food Webs

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The following reference is presented in its entirety as it summarizes the unsustainable
practice of many global fisheries.

The research of Dr. Pauly of UBC is an example here of our Marine people profiles.

The problem of by-catch is essential in dealing with sustainable fisheries.
1. Fishing Down Marine Food Webs http://naturalscience.com/ns/cover/cover6.html
2. Marine Food Webs
http://oceanworld.tamu.edu/resources/oceanography-book/marinefoodwebs.htm
This is an online textbook with several graphics illustrating the point. See the
“fishing down marine food web” diagram at the end of page.2.
Fishing Down Marine Food Webs, Daniel Pauly, * Villy
Christensen, Johanne Dalsgaard, Rainer Froese, Francisco Torres Jr.

Science: 6 February 1998 Vol. 279. no. 5352, pp. 860- 863
The mean trophic level of the species groups reported in Food and Agricultural
Organization global fisheries statistics declined from 1950 to
1994. This reflects a gradual transition in landings from long-lived,
high trophic level, piscivorous bottom fish toward short-lived, low
trophic level invertebrates and planktivorous pelagic fish. This effect,
also found to be occurring in inland fisheries, is most pronounced in the
Northern Hemisphere. Fishing down food webs (that is, at lower trophic
levels) leads at first to increasing catches, then to a phase transition
associated with stagnating or declining catches. These results indicate
that present exploitation patterns are unsustainable.
D. Pauly and J.& Dalsgaard, Fisheries Centre, 2204 Main Mall, University
of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
V. Christensen, R.Froese, F.Torres Jr.,
International Center for Living Aquatic Resources Management, M.C. Post
Office Box 2631,0718 Makati, Philippines.

Exploitation of the ocean for fish and marine invertebrates, both wholesome and valuable
products, ought to be a prosperous sector, given that capture
fisheries–in contrast to agriculture and aquaculture–reap harvests that
did not need to be sown. Yet marine fisheries are in a global crisis,
mainly due to open access policies and subsidy-driven over-capitalization(1) It may be argued, however, that the global crisis is mainly one of economics or of governance, whereas the global resource base itself fluctuates naturally. Contradicting this more optimistic view, we show here that landings from global fisheries have shifted in the last 45 years from large piscivorous fishes toward smaller invertebrates and planktivorous fishes, especially in the Northern Hemisphere. This may imply major changes in the structure of marine food webs. Two data sets were used. The first has estimates of trophic levels for 22 different species or groups of fish and invertebrates, covering all statistical categories included in the official Food and Agricultural Organization (FAO) landings statistics(2). We obtained these estimates from 60 published mass-balance trophic models that covered all major aquatic ecosystem types(3, 4). The models were constructed with the Ecopath software(5) and local data that included detailed diet compositions(6). In such models, fractional trophic levels (7) are estimated values, based on the diet compositions of all ecosystemcomponents rather than assumed values; hence, their precision and accuracy
are much higher than for the integer trophic level values used in earlierglobal studies (8). The 22 trophic levels derived from these6 Ecopath applications range from a definitional value of 1 forprimary producers and detritus to 4.6 (± 0.32) for snappers(family Lutjanidae) on the shelf of Yucatan, Mexico (9). The second dataset we used comprises FAO global statistics (2) of fisheries landings forthe years from 1950 to 1994 which are based on reportssubmitted annually by FAO member countries and other states and wererecently used for reassessing world fisheries potential (10). By combiningthese data sets we could estimate the mean trophic level of landings,presented here as time series by different groupings of all FAO statistical areas and for the world (11). For all marine areas,
the trend over the past 45years has been a decline in the mean trophic level of the fisheries landings, from slightly more than 3.3 in the early 1950s to less than 3.1 in 1994 (Fig. 1A). A dip in the 1960s and early 1970s occurred because of extremely large catches
(106 metric tons (t) per year) of Peruvian anchoveta with a low trophic level (12) of 2.2(±0.42). Since the collapse of the Peruvian anchoveta fishery in 1972-1973, the global trend in the trophic level of marine fisheries landings has been one of steady
decline. Fisheries in inland waters exhibit, on the global level, a similar trend as for the marine areas (Fig. 1B): A clear decline in average trophic level is apparent from the early 1970s, in parallel to, and about 0.3 units below, those of marine catches. The previous
plateau, from 1950 to 1975, is due to insufficiently detailed fishery statistics for the earlier decades (10).Fig. 1. Global trends of mean trophic level of fisheries landings, 1950 to 1994. (A) Marine areas; (B) inland areas. [View Larger Version of this Image (13K GIF file)] In northern temperate areas where the fisheries are most developed, the mean trophic level of the landings has declined steadily over the last two decades. In the North Pacific (FAO areas 61 and 67; Fig. 2A), trophic levels peaked in the early 1970s and have since then
decreased rapidly in spite of the recent increase in landings of Alaska
pollock, Theragra chalcogramma, which has a relatively high trophic level
of 3.8 (±0.24). In the Northwest Atlantic (FAO areas 21and 31; Fig. 2B), the fisheries were initially dominated by planktivorous menhaden, Brevoortia spp., and other small pelagics at low trophic levels. As their landings decreased, the average trophic level of
the fishery initially increased, then in the 1970s it reversed to a steep
decline. Similar declines are apparent throughout the time series for the
Northeast Atlantic (FAO area 27; Fig. 2C) and the Mediterranean (FAO area
37; Fig. 2C), although the latter system operates at altogether lower trophic levels.
Fig. 2. Trends of mean
trophic level of fisheries landings in northern temperate areas,
1950 to 1994. (A) North Pacific (FAO areas 61and 67); (B)
Northwest and Western Central Atlantic (FAO areas 21 and 31); (C)
Northeast Atlantic (FAO area 27); and (D) Mediterranean (FAO area 37).
[View Larger Version of this Image (13K GIF file)]

The Central Eastern Pacific (FAO area 77; Fig. 3A), Southern
and Central Eastern Atlantic (FAO areas 41,47,and 34; Fig.
3B), and the Indo-Pacific (FAO areas 51,57,and 71; Fig. 3C)
show no clear trends over time. In the southern Atlantic this is probably
due to the development of new fisheries, for example, on the Patagonian
shelf, which tends to mask declines of trophic levels in more developed
fisheries. In the Indo-Pacific area, the apparent stability is certainly
due to inadequacies of the statistics, because numerous accounts exist
that document species shifts similar to those that occurred in northern
temperate areas (13)
Fig. 3. Trends of mean trophic levels of fisheries landings in the intertropical belt and
adjacent waters. (A) Central Eastern Pacific (FAO area 77); (B) Southwest,
Central Eastern, and Southeast Atlantic (FAO areas 41,34,and
47); and (C) Indo (west)- Pacific (FAO areas 51,57,and 71).
[View Larger Version of this Image (10K GIF file)] The South Pacific areas (FAO areas 81and 87; Fig. 4A) are
interesting in that they display wide-amplitude fluctuations of trophic
levels, reflecting the growth in the mid-1950s of a huge industrial
fishery for Peruvian anchoveta. Subsequent to the anchoveta fishery
collapse, an offshore fishery developed for horse mackerel, Trachurus
murphyi, which has a higher trophic level (3.3 ± 0.21) and whose
range extends west toward New Zealand (14). Antarctica (FAO areas
48 58 and 88; Fig. 4B) also exhibits high-amplitude variation
of mean trophic levels, from a high of 3.4 due to a fishery that
quickly depleted local accumulations of bony fishes, to a low of
2.3 due to Euphausia superba (trophic level 2.2;±0.40), a
large krill species that dominated the more recent catches.
Fig. 4. High-amplitude changes of mean trophic
levels in fisheries landings. (A) South Pacific (FAO areas 81and
87); (B) Antarctica (FAO areas 48,58,and 88). [View Larger
Version of this Image (8K GIF file)]
The
gross features of the plots in Figs. through 4 while consistent with
previous knowledge of the dynamics of major stocks, may provide new
insights on the effect of fisheries on ecosystems. Further interpretation
of the observed trends is facilitated by plotting mean trophic levels
against catches. For example, the four systems in Fig. 5 illustrate
patterns different from the monotonous increase of catch that may be
expected when fishing down food webs (15). Each of the four systems in
Fig. 5 has a signature marked by abrupt phase shifts. For three of the
examples, the highest landings are not associated with the lowest trophic
levels, as the fishing-down-the-food-web theory would predict. Instead,
the time series tend to bend backward. The exception (where landings
continue to increase as trophic levels decline) is the Southern Pacific
(Fig. 5C), where the westward expansion of horse mackerel fisheries is
still the dominant feature, thus masking more local effects.
Fig. 5. Plots of mean trophic levels in fishery
landings versus the landings (in millions of metric tons) in four marine
regions, illustrating typical backward-bending signatures (note variable
ordinate and abcissa scales). (A) Northwest Atlantic (FAO area 21); (B)
Northeast Atlantic (FAO area 27); (C) Southeast Pacific (FAO area 87); (D)
Mediterranean (FAO area 37). [View Larger Version of this Image (18K GIF
file)] The backward-bending feature of
the plots of trophic levels versus landings, which also occurs in areas
other than those in Fig. 5, may be due to a combination of the following:
(i) artifacts due to the data, methods, and assumptions used; (ii) large
and increasing catches that are not reported to FAO; (iii) massive
discarding of bycatches (16) consisting predominantly of fish with low
trophic levels; (iv) reduced catchability as a result of a decreasing
average size of exploitable organisms; and (v) fisheries-induced changes
in the food webs from which the landings were extracted. Regarding item
(i), the quality of the official landing statistics we used may be seen as
a major impediment for analyses of the sort presented here. We know that
considerable under- and misreporting occur (16). However, for our
analysis, the overall accuracy of the landings is not of major importance,
if the trends are unbiased. Anatomical and functional considerations
support our assumption that the trophic levels of fish are conservative
attributes and that they cannot change much over time, even when ecosystem
structure changes (17). Moreover, the increase of young fish as a
proportion of landings in a given species that result from increasing
fishing pressure would strengthen the reported trends, because the young
of piscivorous species tend to be zooplanktivorous (18) and thus have
lower trophic levels than the adults. Items (ii) and (iii) may be more
important for the overall explanation. Thus, for the Northeast Atlantic,
the estimated (16) discard of 3.7 106 t year1 of bycatch would
straighten out the backward-bending curve of Fig. 5B. Item (iv)
is due to the fact that trophic levels of aquatic organisms are inversely
related to size (19). Thus, the relation between trophic level and catch
will always break down as catches increase: There is a lower size limit
for what can be caught and marketed, and zooplankton is not going to be
reaching our dinner plates in the foreseeable future. Low catchability due
to small size or extreme dilution (<1 g m3) is, similarly, a major
reason why the huge global biomass (109 t) of lanternfish (family
Myctophidae) and other mesopelagics (20) will continue to remain latent
resources. If we assume that fisheries tend to switch from
species with high trophic levels to species with low trophic levels in
response to changes of their relative abundances, then the
backward-bending curves in Fig. 5 may be also due to changes in ecosystem
structure, that is, item (v). In the North Sea, Norway pout, Trisopterus
esmarkii, serves as a food source for most of the important fish species
used for human consumption, such as cod or saithe. Norway pout is also the
most important predator on euphausiids (krill) in the North Sea (3). We
must therefore expect that a directed fishery on this small gadoid
(landings in the Northeast Atlantic are about 3 ? 105 t year1)
will have a positive effect on the euphausiids, which in turn prey on
copepods, a much more important food source for commercial fish species
than euphausiids. Hence, fishing for Norway pout may have a cascading
effect, leading to a build-up of nonutilized euphausiids. Triangles such
as the one involving Norway pout, euphausiids, and copepods, and which may
have a major effect on ecosystem stability, are increasingly being
integrated in ecological theory (21), especially in fisheries biology
(22). Globally, trophic levels of fisheries landings appear to
have declined in recent decades at a rate of about 0.1 per decade,
without the landings themselves increasing substantially. It is likely
that continuation of present trends will lead to widespread fisheries
collapses and to more backward-bending curves such as in Fig. 5, whether
or not they are due to a relaxation of top-down control (23). Therefore,
we consider estimations of global potentials based on extrapolation of
present trends or explicitly incorporating fishing-down-the-food-web
strategies to be highly questionable. Also, we suggest that in the next
decades fisheries management will have to emphasize the rebuilding of fish
populations embedded within functional food webs, within large “no-take”
marine protected areas (24)
2. Sequential
megafaunal collapse in the North Pacific Ocean: An ongoing legacy of
industrial whalingfrom:http://www.pnas.org/cgi/content/full/100/21/12223
Published online , 2003,
Abstract:
Populations of seals, sea lions, and sea otters have
sequentially collapsed over large areas of the northern North Pacific
Ocean and southern Bering Sea during the last several decades. A bottom-up
nutritional limitation mechanism induced by physical oceanographic change
or competition with fisheries was long thought to be largely responsible
for these declines. The current weight of evidence is more consistent with
top-down forcing. Increased predation by killer whales probably drove the
sea otter collapse and may have been responsible for the earlier pinniped
declines as well. We propose that decimation of the great whales by
post-World War II industrial whaling caused the great whales’ foremost
natural predators, killer whales, to begin feeding more intensively on the
smaller marine mammals, thus “fishing-down” this element of the marine
food web. The timing of these events, information on the abundance, diet,
and foraging behavior of both predators and prey, and feasibility analyses
based on demographic and energetic modeling are all consistent with this
hypothesis.
The abrupt decline of the
western stock of Steller sea lions (Eumetopias jubatus) across most of
the northern North Pacific Ocean and southern Bering Sea is one of the
world’s most well known yet poorly understood marine conservation
problems. For years, scientists attributed this decline to nutritional
limitation, the presumed consequence of a climate regime shift and/or
competition with regional fisheries (1). Although fisheries and regime
shifts undoubtedly influenced both the fishes and their associated food
webs (2–5), several recent reviews of the available information on sea
lions and their environment, including an assessment by the National
Research Council, cast doubt on the nutritional limitation hypothesis (6,
7), notwithstanding evidence from field and laboratory studies that diet
quality is a factor in sea lion energetics (8). The doubt stems from three
main findings. First, most measures of behavior, physiology, and
morphology from surviving adult sea lions and pups in the western Gulf of
Alaska and Aleutian Islands are inconsistent with nutritional limitation.
These animals have better body condition, reduced foraging effort, and
reduced field metabolic rates relative to similar measures from the
increasing sea lion population in southeast Alaska (7). Second, sea lion
prey is abundant in most areas of the decline (9). Known changes in prey
availability and other features of the oceanic ecosystem are particularly
incongruous with the most precipitous phase of the decline, which occurred
during the mid- to late 1980s, and can be accounted for only by greatly
increased adult mortality (6). Third, populations of piscivorous sea
birds, many of which feed on earlier life stages of the same fish species
consumed by sea lions, have remained stable or increased in the same area
and over the same period that the sea lions have declined (10). Top-down
forcing now appears to have been an important contributor to declines of
Steller sea lions and other marine mammal populations in the region (6).
Likely top-down forcing factors include purposeful shooting, incidental
mortality in fishing gear, and predation. We will suggest that increased
predation was paramount among these factors, and that altered food web
dynamics brought about by human overharvesting initiated the
change.
In the
report “Progress Towards Environmental Sustainability in British
Columbia’s Seafood Sector., May 2001” there are a number of excellent
graphics which present a framework for sustainable fisheries.
http://www.bcseafoodalliance.com/BCSA/AMRSummitReport.pdf
5.4 The Precautionary Principle:

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5.0 Humans as a Part of Ocean Systems:

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5.1 FISHERIES POLICIES FOR SUSTAINABILITY:

If Seafood fisheries in British Columbia are to remain sustainable then there must be adherence to a regime of regulations . Management of fisheries in the past has often led to depletion of resources. Examples can be drawn from herring and salmon resources in BC, the anchovy and sardine examples of Pacific Coast of North and South America, and the Atlantic Cod. The unsustainable practises of Drift net fisheries, bottom trawling, and by-catch are examples of why there are problems.(see reference No.5 below).

Here is an opportunity to emphasize best practices for ecologically sustainable fisheries. The Precautionary Principle is at the base of a requirement for sustainable fisheries.
Resource references:
1. In the report “Progress Towards Environmental Sustainability in British Columbia’s Seafood Sector., May 2001″ there are a number of excellent graphics which present a framework for sustainable fisheries.
http://www.bcseafoodalliance.com/BCSA/AMRSummitReport.pdf

The topics below are dealt with in length and provide excellent examples of displays and interactive presentations which could be set up on sustainable fisheries.

Sustainable Fishing and Aquaculture
Sustainable Harvest of Target species and Stocks
Limiting the impacts of Fisheries on Non-Target species,
Limiting Impacts on Habitats and Ecosystems
Ensuring effective management and regulation.

2. The Geoduck Fishery: has established a Code of Conduct for responsible Fishing.

http://www.geoduck.org/pdf/UHA_Code_Report.pdf

3. 2006 BC Seafood Industry report http://www.env.gov.bc.ca/omfd/reports/YIR-2006.pdf

4. Seafood Statistics:

http://www.env.gov.bc.ca/omfd/fishstats/index.html

5. FIsheries Issues:
http://oceanworld.tamu.edu/resources/oceanography-book/fisheriesissues.htm

Go to the sustainable aquaculture section

5.2 The Ecosystem Approach

From: http://www.worldwatch.org/node/5352 Oceans in Peril: Protecting Marine Biodiversity publ 2007

An ecosystem approach promotes both conservation and the sustainable use of marine resources in an equitable way. It is a holistic approach that considers environmental protection and marine management together, rather than as two separate and mutually exclusive goals. Paramount to the application of this approach is the establishment of networks of fully protected marine reserves, in essence, “national parks” of the sea. These provide protection of whole ecosystems and enable biodiversity to both recover and flourish. They also benefit fisheries by allowing for spillover of fish and larvae or eggs from the reserve into adjacent fishing grounds.
Outside of the reserves, an ecosystem approach requires the sustainable management of fisheries and other resources. Demands on marine resources must be managed within the limits of what the ecosystem can provide indefinitely, rather than being allowed to expand as demographic and market forces dictate. An ecosystem approach requires protection at the level of the whole ecosystem. This is radically different from the current practice, where most fisheries management measures focus simply on single species and do not consider the role of these species in the wider ecosystem.
An ecosystem approach is also precautionary in nature, meaning that a lack of knowledge should not excuse decision-makers from taking action, but rather lead them to err on the side of caution. The burden of proof must be placed on those who want to undertake activities, such as fishing or coastal development, to show that these activities will not harm the marine environment. In other words, current presumptions that favor freedom to fish and freedom of the seas will need to be replaced with the new concept of freedom for the seas.”

Reference:

1.Canessa, R., Conley, K., and Smiley, B. 2003. Bowie Seamount Marine Protected Area: an ecosystem overview report. Can. Tech. Rep. Fish. Aquat. Sci., 2461. …
http://www.seaaroundus.org/…/ASynthesisResearchActivitiesFCEcosystemBaseFish.pdf –

2. http://archive.nafo.int/open/sc/2008/scs08-10.pdf.

Northwest Atlantic Fisheries Organization Serial No. N5511 NAFO SCS Doc. 08/10 SCIENTIFIC COUNCIL MEETING – JUNE 2008 Report of the NAFO Scientific Council Working Group on Ecosystem Approach to Fisheries Management (WGEAFM) NAFO Headquarters, Dartmouth, Canada 26-30 May 2008.

In recognition of an amended NAFO Convention (currently awaiting ratification) which has principles of an Ecosystem
Approach to Fisheries Management, Scientific Council established a Working Group on the Ecosystem Approach to
Fisheries Management in September 2007. Terms of Reference (ToR1) for this WG relate to the identification of eco-
regions within the NAFO Convention Area (NCA) and the development of ecosystem health indicators.

3. A synthesis of Research Activities at the Fisheries Centre on Ecosystem-based Fisheries Modelling and Assessment with emphasis on the Northern and Central Coast of BC..2007,
S.Guenete,V.Christiansen,C. Hover,M.Lam D.Preikshot, D. Pauly

5.3 Fishing Down Food webs

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4.3 Ocean Pollutants

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4.3 Ocean Pollutants:

A major problem with maintaining sustainable oceans is the global contaminations from atmospheric and direct point source pollution.

Probably the greatest single issue that needs to be dealt with here is that of the possibility of opening up the Coastal areas for offshore drilling. Our ability to debate this is a good test of how serious we are about thinking about marine resource sustainability for the future.

As theSierra Club puts it:
http://www.sierraclub.ca/bc/programs/marine/issue.shtml?x=550&als[URL_ITEM]=24ad1fd0ec90a1265449091eeba17b55

  • “The ecological risks are too great.
    One oil spill like the 1989 Exxon Valdez spill in Alaska would spell disaster for B.C.’s marine life. Exploration techniques like seismic testing have serious ecological consequences.
  •  Current environmental regulations are inadequate.
    Our provincial environmental regulations have been gutted. Federal legislation such as the Species at Risk Act is toothless. We lack a regime that can protect the natural environment.
  • B.C. needs to look beyond fossil fuel energy sources.
    Developing B.C.’s offshore oil and gas will mean committing to an energy source that has proven to be unsustainable. Canada has to reduce its greenhouse gas emissions to meet Kyoto targets. We need to invest in alternative energy sources now.”

OTHER CHEMICAL CONTAMINANTS harmful in the Marine Environment

Below are portrayed the records of some countries with good news stories. Find as many of these as possible to show that it is possible to do things right. Also see the section on types of demos and take aways for related ideas.
Reference: From:” WATER” http://www.unep.org/geo/geo4/report/04_Water.pdf

“Persistent organic pollutants (POPs) are synthetic organic chemicals that have wide-ranging human and environmental impacts (see Chapters 2, 3 and 6). In the late 1970s, studies of the North American Great Lakes highlighted the existence of older, obsolete chlorinated pesticides (so-called legacy chemicals) in sediments and fish (PLUARG 1978). As regulations curtailing their use were implemented, chemical levels have declined in some water systems since the early 1980s (see Chapter 6) (see Box 6.28). Similar declines have since been observed in China and the Russian Federation (see Figure 4.10). The estimated production of hazardous organic chemical-based pollutants in the United States by industry alone is more than 36 billion kilogrammes/ year, with about 90 per cent of these chemicals not being disposed of in an environmentally responsible manner (WWDR 2006). The chemicals in pesticides can also contaminate drinking water through agricultural run-off. There is growing concern about the potential impacts on aquatic ecosystems of personal-care products and pharmaceuticals such as birth-control residues, painkillers and antibiotics. Little is known about their long-term impacts on human or ecosystem health, although some may be endocrine disruptors. Some heavy metals in water and sediments accumulate in the tissues of humans and other organisms. Arsenic, mercury and lead in drinking water, fish and some crops consumed by humans have caused increased rates of chronic diseases. Marine monitoring conducted since the early 1990s in Europe indicates decreasing cadmium, mercury and lead concentrations in mussels and fish from both the northeast Atlantic Ocean and Mediterranean Sea. Most North Sea states achieved the 70 per cent reduction target for these metals, except for copper, and tributyltin (EEA 2003). Although occurring in some inland locations, such as the Upper Amazon, oil pollution remains primarily a marine problem, with major impacts on seabirds and other marine life, and on aesthetic quality. With reduced oil inputs from marine transportation, and with vessel operation and design improvements, estimated oil inputs into the marine environment are declining (UNEP-GPA 2006a) (see Figure 4.11), although in the ROPME Sea Area about 270 000 tonnes of oil are still spilled annually in ballast water. The total oil load to the ocean includes 3 per cent from accidental spills from oil platforms, and 13 per cent from oil transportation spills (National Academy of Sciences 2003). Despite international efforts, solid waste and litter problems continue to worsen in both freshwater and marine systems, as a result of inappropriate disposal of non- or slowly degradable materials from land-based and marine sources (UNEP 2005a).”

4.5 Beach or Coastal Modification and Implications

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4.3 Oxygen Depletion in the Ocean

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OXYGEN DEPLETION: A harmful algal bloom of the dinoflagellates Noctiluca scintillans, known as a red tide Organic materials, from such sources as algal blooms and discharges from domestic wastewater treatment plants and food-processing operations, are decomposed by oxygen-consuming microbes in waterbodies. This pollution is typically measured as the biochemical oxygen demand (BOD). High BOD levels can cause oxygen depletion, jeopardizing fish and other aquatic species. Lake Erie’s oxygen- depleted bottom zone, for example, has expanded since 1998, with negative environmental impacts. Some coastal areas also undergo oxygen depletion, including the eastern and southern coasts of North America, southern coasts of China and Japan, and large areas around Europe (WWAP 2006).

  • From: Research Document – 2012/072

State of physical, biological, and selected fishery resources of Pacific Canadian marine ecosystems in 2011

By J.R. Irvine and W.R. Crawford

Scientists have reported alarmingly low oxygen concentrations in near-shore waters of the Oregon coast in summer, being in 2002 and most severely in 2006. High crab mortalities on the ocean bottom took place in these summers. Low oxygen concentrations (less than 1 ml/L) have also been observed on off southwest Vancouver Island since 2002, with concentrations of 0.7 ml/L at 150 metres depth recorded in 2006 and 2009, the lowest in the 50-year record. Concentration was 1.0 and 1.1 ml/L in 2010 and 2011, respectively. Hypoxia on the Canadian shelf is much less severe than off Oregon and Washington, and mortality of bottom life has not been reported.

  • From swissinfo.ch : Oceans could run out of oxygen

by Isobel Leybold-Johnson, swissinfo.ch
Feb 11, 2012 – 14:03

Global warming could lead to more of the world’s oceans becoming “dead zones” – where a lack of oxygen leads to marine life dying out.

This was the conclusion of recent analysis of marine oxygen conditions over the past 20,000 years, co-authored by the Federal Institute of Technology Zurich (ETHZ).

Oceans are already oxygen-starved in places: every summer some areas of the northeastern Pacific see huge numbers of dead fish, shrimp or molluscs washed up on beaches.

This is caused by marine animals suffocating because the water contains too little of the vital O2 they need to breathe – or none at all. It is not only an ecological problem, the local fishing industry is affected as well.

Currently around 15 per cent of oceans are considered oxygen-depleted or anoxic “dead zones”.

“There’s been a very longstanding debate about the influence of global warming on the concentration of oxygen in the ocean, basically because the ocean oxygen concentration measurements of the past decades have not been very conclusive,” Samuel Jaccard from the ETHZ’s Geological Institute told swissinfo.ch.

This is why Jaccard and Eric Galbraith from McGill University in Canada decided to go back in time and reconstruct how the oxygen content has changed in oceans in the past 20,000 years, with the focus on the Pacific and Indian Oceans.

Temperature rise

Their study, published in Nature Geoscience, showed that the average global temperature rise of around at least two degrees Celsius between the peak and the end of the last Ice Age (between about 10,000-20,000 years ago) had a massive effect on the oxygen content of seawater.

“The warmer the global average temperature, the more extended the oxygen minimum zones are, so the volume of these oxygen-poor water bodies is more extended during warm periods than in cold periods,” Jaccard said.

What is worrying is that, currently, global average temperature is predicted to rise by at least two degrees in the coming century due to climate change. This is of a similar magnitude to the warming the planet has undergone since the last Ice Age 20,000 years ago.

“So we would assume that if, indeed, temperatures are increasing in the next 100 years, these oxygen minimum zones would also increase in volume and that the general oxygen concentration of the ocean will decrease,” Jaccard said.

And what is more: “our analysis has shown that not only was absolute temperature important, but also the rate of change, so the faster the warming, the more expanded these zones are”.

Oxygen in seawater mainly comes from gas exchange between the water’s surface and the atmosphere. As temperatures at the surface increase, the dissolved oxygen supply below the surface gets used up more quickly. It’s a little like turning down the oxygen pump in a fish tank, says Jaccard.

Suffering oceans

Dead zones are a topic well known to green campaigners and are not just limited to the biodiversity-rich deep oceans, explains Jochen Lamp, a marine expert at WWF in Germany.
 
They also affect the shallow seas like the Baltic Sea, which are subject to eutrophication: when nutrients from the land and agriculture cause over-enrichment of the water and the growth of algal blooms. These blooms then deplete the water’s oxygen.

But whereas it is easier to tackle shallow seas dead zones by controlling nutrient input, such as by having low nutrient agriculture, climate change adaptation is “a much more long lasting and complicated process”, said Lamp.

Even if countries such as Switzerland can agree on measures – the Rio+20 conference on sustainable development is scheduled for June – the change in the trend may not be seen for 50-70 years, he added.

Overall the world’s oceans are suffering: there is also overfishing and the other effects of climate change like the acidification of the waters.

Oceans are a delicately balanced ecosystem. “We hope that the balance will re-establish, but there is a lot of human impact in this imbalance and we do not yet know what will happen in reality during the next decades,” warned Lamp.

Isobel Leybold-Johnson, swissinfo.ch

Jaccard SL & Galbraith ED. Large climate-driven changes of oceanic oxygen concentrations during the last deglaciation.

The article was published online in Nature Geoscience on December 18, 2011. The research was highlighted in the ETH Life journal in January 2012.

Deep water in the North Pacific Ocean already has the most acidic water in the global ocean and the British Columbia continental shelf might see negative impacts of this feature sooner than most oceanic waters.

Oxygen depletion in the Gulf of Mexico has created a huge ‘dead zone,’ with major negative impacts on biodiversity and fisheries (MA 2005) (see Chapter 6).

4.4 Ocean Pollutants

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4.2 The Importance of pH

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The Importance of pH:
The issue of ocean Acidification linked to Climate Change now has a a serious implication for Shellfish Producers. Their website reflects these concerns: http://bcsga.ca/ocean-acidification/

oceanprofileA few physical factors have a disproportionate effect on the distribution of organisms and the fact that humans play a large role in their modification means that their effects on the sustainability of ecosystems is rather importantaragonite, ph
Canadian Science Advisory Secretariat Research Document – 2008/013 State of physical, biological, and selected fishery resources of Pacific Canadian marine ecosystems(Page 37 of pdf file) Ocean acidification off the West Coast by Debby Ianson, Fisheries and Oceans Canada “Global oceans are becoming more acidic due to increasing carbon dioxide (Orr et al. 2005). Much of the extra CO2 released by burning fossil fuels ends up in the oceans, increasing the dissolved inorganic carbon concentration (DIC). As DIC increases, the relative proportions of carbon species shift (specifically from the carbonate ion to the bicarbonate ion), resulting in an increase in acidity and a decrease in pH (Strum and Morgan, 1981).

At present the pH of seawater has decreased by about 0.1 due to oceanic uptake of anthropogenic carbon and is projected to decrease by 0.4 by the year 2050 (Orr et al. 2005). The decrease in pH (and concurrent decrease in carbonate ion) means that organisms that produce calcite and aragonite shells or structures, such as pteropods, corals and shellfish, are threatened (The Royal Society, 2005).” “Very few data from the carbonate system have been collected on the Canadian west coast; however these few observations show that Juan de Fuca Strait and the Vancouver Island Coastal Current experience high pCO2 water due to tidal mixing in the Strait, which brings water high in DIC and low in pH to the surface (Ianson et al. 2003). An additional study with high spatial resolution confirms the high surface pCO2 (400 — 800 ppm; Nemcek et al, in press) in this area estimated by Ianson et al. (2003) but has no complimentary measurements (such as DIC) with which to determine pH in the Strait.”

From “WATER: http://www.unep.org/geo/geo4/report/04_Water.pdf Rainwater and ocean acidification Acidity in rainwater is caused by the dissolution of atmospheric CO2, as well as by atmospheric transport and deposition of nitrogen and sulphur compounds (see Chapters 2 and 3). This is important because biological productivity is closely linked to acidity (see Chapter 3). The box on acidifying cycles in Chapter 3 describes some of the impacts of acid deposition on the world’s forests and lakes. The oceans have absorbed about half of the global CO2 emissions to the atmosphere over the past 200years (see Chapter 2), resulting in the increasing acidification of ocean waters (The Royal Society 2005). Acidification will continue, regardless of any immediate reduction in emissions. Additional acidification would take place if proposals to release industrially produced and compressed CO2 at or above the deep sea floor are put into practice (IPCC 2005). To date, injection of CO2 into seawater has been investigated only in small-scale laboratory experiments and models. Although the effects of increasing CO2 concentration on marine organisms would have ecosystem consequences, no controlledecosystem experiments have been performed in the deep ocean nor any environmental thresholds identified. The impacts of ocean acidification are speculative, but could be profound, constraining or even preventing the growth of marine animals such as corals and plankton. They could affect global food security via changes in ocean food webs, and, at the local scale, negatively affect the potential of coral reefs for dive tourism and for protecting coastlines against extreme wave events. It is presently unclear how species and ecosystems will adapt to sustained, elevated CO2 levels (IPCC 2005). Projections give reductions in average global surface ocean pH (acidity) values of between 0.14and 0.35units over the 21st century, adding to the present decrease of 0.1 units since pre-industrial times(IPCC 2007). Managing water issues related to climate change Global-scale changes to the water environment associated with climate change include higher sea surface temperatures, disruption of global ocean currents, changes in regional and local precipitation patterns, and ocean acidification. These issues are typically addressed through global efforts, such as the UN Framework Convention on Climate Change and its Kyoto Protocol (see Chapter 2). Management at the global level involves numerous actions at regional, national and local scales. Many global conventions and treaties are implemented on this basis, with their effectiveness depending on the willingness of individual countries to contribute to their achievement. Because these changes are linked to other environmental issues (for example, land use and biodiversity), they must also be addressed by other binding or non-binding treaties and instruments (see Chapter 8). Major responses to the drivers of climate change – primarily the increased burning of fossil fuels for energy – are analysed in Chapter 2. These responses are generally at the international level, and require concerted action by governments over the long-term, involving legal and market- driven approaches. Focus is on responses to climate change-related impacts affecting the water environment that involve regulation, adaptation and restoration

Pacific Ocean acid levels jeopardizing marine life

Vancouver Island researchers use artificial tide pools to study threat
From CBC News
Posted: Jul 17, 2012 2:17 AM PT
Last Updated: Jul 17, 2012 12:19 PM PT

Very few data from the carbonate system have been collected on the Canadian west coast; however these few observations show that Juan de Fuca Strait and the Vancouver
Island Coastal Current experience high pCO2 water due to tidal mixing in
the Strait, which brings water high in DIC and low in pH to the surface
(Ianson et al. 2003).

An additional study with high spatial resolution
confirms the high surface pCO2 (400 — 800 ppm; Nemcek et al, in press) in
this area estimated by Ianson et al. (2003) but has no complimentary
measurements (such as DIC) with which to determine pH in the Strait.”
The foillowing is taken from the publication:”WATER”
“http://www.unep.org/geo/geo4/report/04_Water.pdf”

Rainwater and ocean acidification : Acidity in rainwater is caused by the dissolution
of atmospheric CO2, as well as by atmospheric transport and deposition of
nitrogen and sulphur compounds (see Chapters 2 and 3). This is important
because biological productivity is closely linked to acidity (see Chapter
3). The box on acidifying cycles in Chapter 3 describes some of the
impacts of acid deposition on the world’s forests and lakes. The oceans
have absorbed about half of the global CO2 emissions to the atmosphere
over the past 200years (see Chapter 2), resulting in the increasing
acidification of ocean waters (The Royal Society 2005). Acidification will
continue, regardless of any immediate reduction in emissions. Additional
acidification would take place if proposals to release industrially
produced and compressed CO2 at or above the deep sea floor are put into
practice (IPCC 2005). To date, injection of CO2 into seawater has been
investigated only in small-scale laboratory experiments and models.
Although the effects of increasing CO2 concentration on marine organisms
would have ecosystem consequences, no controlled ecosystem experiments have
been performed in the deep ocean nor any environmental thresholds
identified. The impacts of ocean acidification are speculative, but could
be profound, constraining or even preventing the growth of marine animals
such as corals and plankton. They could affect global food security via
changes in ocean food webs, and, at the local scale, negatively affect the
potential of coral reefs for dive tourism and for protecting coastlines
against extreme wave events. It is presently unclear how species and
ecosystems will adapt to sustained, elevated CO2 levels (IPCC 2005).
Projections give reductions in average global surface ocean pH (acidity)
values of between 0.14and 0.35units over the 21st century, adding to the
present decrease of 0.1 units since pre-industrial times(IPCC 2007).

Managing water issues related to climate change Global-scale changes to the water
environment associated with climate change include higher sea surface
temperatures, disruption of global ocean currents, changes in regional and
local precipitation patterns, and ocean acidification. These issues are
typically addressed through global efforts, such as the UN Framework
Convention on Climate Change and its Kyoto Protocol (see Chapter 2).
Management at the global level involves numerous actions at regional,
national and local scales. Many global conventions and treaties are
implemented on this basis, with their effectiveness depending on the
willingness of individual countries to contribute to their achievement.
Because these changes are linked to other environmental issues (for
example, land use and biodiversity), they must also be addressed by other
binding or non-binding treaties and instruments (see Chapter 8). Major
responses to the drivers of climate change – primarily the increased
burning of fossil fuels for energy – are analyzed in Chapter 2. These
responses are generally at the international level, and require concerted
action by governments over the long-term, involving legal and market-
driven approaches. Focus is on responses to climate change-related impacts
affecting the water environment that involve regulation, adaptation and
restoration .

4.3 Oxygen depletion

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4.0 Physical or Abiotic Factors

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4.0 Physical or Abiotic Factors

Part of the structure of an ecosystem is its physical factors. The opportunity in the Marine Centre to demonstrate the close dependence of organisms on physical factors cannot be missed. It is a good way to emphasize to the public that one cannot seperate the physical and the living world and therefore one has to recognize that changing physical factors will have a direct impact on biodversity and the integrity of marine ecosystems. It is also an opportunity to break down the artificial barriers between biology, physics, chemistry and geology.

An approach which I have used on the racerocks.com website has been to treat all physical factors in terms of how they affect life organisms. Measuring the factor is one aspect , but recognizing the impact that those factors have on organisms presents a more interesting aspect. See examples on the links from the data page index at: http://www.racerocks.com/racerock/eco/ecodata.htm

So much of how we interact with Marine environments may influence the physical factors in which organisms have evolved to live for millions of years. Present the wide array of factors, with sensor feeds from a number of ecosystems.. Have specific examples of how the distribution of organisms is determined by those factors and how humans are changing some of those factors too quickly. A few summary points follow:

  • Successional changes caused by changes of abiotic factors.
  • The Physical Story. The marriage of the physical and life sciences.
  • How geology-topography affects the distribution of life.
  • A display of life zones and biodiversity connected to physical factors.
  • Live remote camera control station. Available on Kiosk mode computers access to several remote control cameras. Some can be located nearby in a secure area ( maybe one of the ponds at James Island.)
  • The marine industries of the Georgia Strait.. the positive things that are happening.
  • How marine industry can be sustainable without contamination and alteration of the physical factors of the environment.
  • Energy budget of a disturbed seabird or mammal video streaming on walls of boats and human activity impacting.
  • Storm drains and implication of runoffs in altering physical factors.
  • Agriculture and the sea… use of fertilizers pesticides on ocean ecosystems. Tie into interconnectivity of ecosystems.
  • Climate change and its effects on the oceans.
  • Part of the Structure and Function of Ecosystems: Role in energy flow and material cycles. Reference: Structure and Function of Ecosystems:http://www.racerocks.com/racerock/education/curricula/projects/structfunct.htm

4.1 Sensors and Data Collection for research.

I have listed here a number of ways to monitor physical factors of ecosystems at various levels and locations..

  • Local monitors of all exhibit tanks to show different parameters.
    • oxygen levels of aerated vs bottom muds
    • ph change as photosynthesis changes in a green pool
    • set up a green tank highly enriched with nutrients for this
    • have a “convertible tank” where automatic changes can be introduced which then can register abiotic changes on the instruments. This provides great opportunities for schools to do research. For instance a tank may have a screen barrier seperating two populations of fish or invertebrates. Oxygen, Co2 pH and other sensors monitors the whole tank. At periodic intervals, a gate is lowered seperating the water bodies of the two tanks, on the monitors, digital or graphics show a timeline and the change in physical factors contrasting the opposing sides.
    • demo of currents feeding barnacles.. ie dependence on that factors
  • Remote site monitors.
    • interactive modelling with temperature data from Race Rocks.. and implications for global change.
    • atmospheric and oceanographic sensors monitoring at Race Rocks.
    • Links and interpretations to physical measurements in real time from the Venus sub-sea research program.
    • Links and interpretations to physical measurements in real time from the Neptune sub-sea research program.
    • Links to the Victoria weather network… school contribution a part of this

4.1 Sensors and the Collection of Physical Data

4.2 The Importance of pH.

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3.2 Integration and Interconnectivity of Marine Ecosystems.

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The three themes to be emphasized here overlap into many other aspects of this report as well. We are talking about Ecosystems that by definition are interrelated. I think it is important to point them out as themes however since they may get overlooked otherwise.

1. Marine ecosystems and the organisms living within them are highly interconnected and interdependant.

2. The ecosystems people  live in and the activities they do in everyday life have a close connection with the welfare of marine ecosystems and their organisms.

3. We manage the resources and activities of different ecosystems in isolated jurisdictions of our governments and if change is to be effected, there are implications here.

—————————————————————————————-

1. A problem with defining the model of any marine system is that we have to draw boundaries which immediately restrict the reality of that system. We have a tendency to want to compartmentalize in order to make sense of things but nature doesn’t really work that way. This point should be made clear when modelling any ecosystem in an exhibit, and at every opportunity, the interactions with other ecosystems should be acknowledged.

  • The anadromous fish story is probably the classic one to show interactions . Not only marine and fresh water systems, but the interconnections with surrounding forests as well.
  • Marine mammals which may haul out on our rocky island ecosystems or swim in our local waters, but may within their lifetime traverse thousands of miles of coastal and open oceans.
  • Plankton distribution and migrations across ecosystems, the foam wind swept onto a beach carrying bits of ocean planktonic debris which is gleaned by a migrating shorebird, probably originated in the open ocean or as larvae in distant rocky intertidal zones.

2. A very constructive public education role can be served by any educational curriculum  in providing viewers with the evidence that the ecosystems in which they live and the activities they do in everyday life have a close connection with the welfare of marine ecosystems and their organisms. Just a few of the areas which can be included are as follows

  • coastal cities and the materials they shed into the water.
  • Agriculture runoff and the influence on eutrophication in marine systems.
  • Introduction of exotic species which compromises the ecological integrity of natural ecosystems
  • marine transportation and its effect
  • marine recreation and its effect on organisms and ecosystems.
  • Marine harvesting activities
  • The activities we do that affect climate change.

The point to make in all of this is that all these activities can have a range of impact from severe to non-significant in terms of how ecosystems are effected. Here again the proposal must be made that this is part of our choice of futures for the ocean.

3. The implications for management of the resources in these overlapping ecosystems becomes clear when one can appreciate that we have allowed different levels of governments to deal with different ecosystems without considering their interactions. It points to the need for a holistic model of ecosystem management, rather than a compartmentalized one. This was one of the intents of the Oceans Act.. to break down that conflict in jurisdictions and have a new way of looking at and ensuring sustainability of the marine environment. The fact that agriculture, forestry, parks, military and fisheries are all managed separately with little appreciation of the ecosystems of their overlapping jurisdictions must be presented in all its absurdity for the public to perhaps start an open dialogue on how sustainability can be insured if we can’t get it right.

As part of biodiversity, the ways that organisms themselves have interdependencies provides a number of opportunities to illustrate interesting interrelationships.

 So how can this be portrayed?

  • Start by finding ( if there are any) some positive examples of ecosystem management which takes into account the interrelated aspects of ecosystems.
  • Present best-case scenarios for marine sustainability issues.
  • In the take-aways section, provide constructive acts for visitors to follow up on in order to try to affect change that recognizes the need for a new method of marine ecosystem management.

3.3 Ecosystem Services and Natural Capital

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3.1.1 Key Species

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Although all parts of an ecosystem are important for its long term sustainability, several species can be selected out which are essential to the operation of the whole system.

  • herring
    need for controls on over-harvesting

Ways these can be impacted:

  • overharvesting,
  • competition from introduced species
  • habitat loss.
  • toxic materials

How to mitigate this..

  • increase in research, baseline standards
  • moratorium on marine system development,
  • need to restore lost habitat
  • need for large areas to be set aside as parks or reserves for habitat now while it is available, later it may diminish.
  • complete detoxification of all run-off waters.
  • “a no negative impact” is the only option for marine developments.
  • recognition of interconnectivity in management of resources.

3.2 Integration and interconnections of Marine Ecosystems

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3.1.0 Ecosystem Integrity

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The values of maintaining ecosystems that function in an unaltered and interconnected way are paramount. The importance of controlling introduced species and the controls that must be placed on fishing have to be emphasized. Habitat loss is a major problem. Without secure habitats, the ecosystem services are degraded. Ecosystems have structure and function . If one sees the many facets that make up a well functioning ecosytem with negative feedback loops keeping it in a steady state, then they may have a better idea about how impacts on the ecosystem can have far-reaching effects.

Reference FROM:” WATER” http://www.unep.org/geo/geo4/report/04_Water.pdf

Ecosystem integrity

Since 1987, many coastal and marine ecosystems and most freshwater ecosystems have continued to be heavily degraded, with many completely lost, some irreversibly (Finlayson and D’Cruz 2005, Argady and Alder 2005) (see Box 4.3). It has been projected that many coral reefs will disappear by 2040 because of rising seawater temperatures (Argady and Alder 2005). Freshwater and marine species are declining more rapidly than those of other ecosystems (see Figure 5.2d). Wetlands, as defined by the Ramsar Convention, cover 9–13 million km2 globally, but more than 50 per cent of inland waters (excluding lakes and rivers) have been lost in parts of North America, Europe, and Australia (Finlayson and D’Cruz 2005). Although data limitations preclude an accurate assessment of global wetland losses, there are many well- documented examples of dramatic degradation or loss of individual wetlands. The surface area of the Mesopotamian marshes, for example, decreased from 15 000–20 000 km2 in the 1950s to less than 400 km2 around the year 2000 because of excessive water withdrawals, damming and industrial development (UNEP 2001) but is now recovering (see Figure 4.12). In Bangladesh, more than 50 per cent of mangroves and coastal mudflats outside the protected Sunderbans have been converted or degraded.

Reclamation of inland and coastal water systems has caused the loss of many coastal and floodplain ecosystems and their services. Wetland losses have changed flow regimes, increased flooding in some places, and reduced wildlife habitat. For centuries, coastal reclamation practice has been to reclaim as much land from the sea as possible. However, a major shift in management practice has seen the introduction of managed retreat for the marshy coastlines of Western Europe and the United States. Although limited in area compared to marine and terrestrial ecosystems, many freshwater wetlands are relatively species-rich, supporting a disproportionately large number of species of certain faunal groups. However, populations of freshwater vertebrate species suffered an average decline of almost 50 per cent between 1987 and 2003, remarkably more dramatic than for terrestrial or marine species over the same time scale (Loh and Wackernagel 2004). Although freshwater invertebrates are less well assessed, the few available data suggest an even more dramatic decline, with possibly more than 50per cent being threatened (Finlayson and D’Cruz 2005). The continuing loss and degradation of freshwater and coastal habitats is likely to affect aquatic biodiversity more strongly, as these habitats, compared to many terrestrial ecosystems, are disproportionately species-rich and productive, and also disproportionately imperiled.

The introduction of invasive alien species, via ship ballast water, aquaculture or other sources, has disrupted biological communities in many coastal and marine aquatic ecosystems. Many inland ecosystems have also suffered from invasive plants and animals. Some lakes, reservoirs and waterways are covered by invasive weeds, while invasive fish and invertebrates have severely affected many inland fisheries. Declines in global marine and freshwater fisheries are dramatic examples of large-scale ecosystem degradation related to persistent overfishing,

http://www.maweb.org/documents/document.358.aspx.pdf

Mitigation of climate change. Sea level rise and increases in
storm surges associated with climate change will result in the
erosion of shores and habitat, increased salinity of estuaries and
freshwater aquifers, altered tidal ranges in rivers and bays,
changes in sediment and nutrient transport, and increased coastal
flooding and, in turn, could increase the vulnerability of some
coastal populations. Wetlands, such as mangroves and flood-
plains, can play a critical role in the physical buffering of climate
change impacts.

3.1.1 Key Species

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