Something Fishy

Commercial, and even hobby fishing, changes the environment in which we dive. Some of this, in all probability, has rather limited impact - such as divers collecting food for their own table or the marine angler catching a few fish over a wreck. If this hobby side increases to taking larger numbers, particularly of specific species, the impact increases proportionately. This has happened with some of the spearfishing competitions of old or extensive collection, such as the abalone off the California coast or large yachts filling holds in the Bahamas. But the diving community can and do help a lot in conservation. It's the commercial side which is mostly causing problems of fish depletion, and potentially complete destruction of whole ecosystems.

Some of these commercial practices target slowly-maturing or rare animals: sharks, whales, turtles, Patagonian toothfish (Chilean seabass) and many others. Other practices simply take such large numbers that even animals which reproduce relatively quickly, such as cod which reach maturity within 3-5 years, can't keep up with the depletion. Some practices cause problems as a side effect, such as that of bycatch, habitat destruction, pollution or genetic contamination.

There are two aspects to this.

Chilean seabass live at least 40 years, orange roughy at least 100. Large grouper are thought to live about 30 years. A Pacific rockfish caught in 2001 was 205 years old? But generally we know little about the life expectancy of fish.

1st - People need food
2nd - Some products have a status beyond food; from folk medicines to a show of wealth

Both of these aspects will and do claim to be legitimate, depending on the culture (country) making the claim. The fishermen and the communities they supply will also argue for the jobs created. Fishing provides a significant proportion of necessary protein and micro nutrients, particularly for some of the most vulnerable populations in poorer island and coastal communities. Is it a bit of cultural imperialism to prevent a market we don't like on moral grounds?

Less of a debating topic but still controversial are regulations to insure :
1st - Sustainability
2nd - Efficient use of anything caught
3rd - Minimising habitat destruction
4th - Maintaining biodiversity

As divers we are in a unique position to do some really positive things to bring about changes. In other areas we are only part of the general population, but hopefully on the more informed side.

The Seabed
Dragging heavy fishing gear over the seabed might be likened to hunting for rabbits with a bulldozer. As we know from first-hand experience as divers, the seabed has a multitude of organisms living in a complex landscape, its not a flat monoculture.

Even a sandy bed with scallops has rocks with sea fans, anemones, etc. while on and under the sand itself starfish, crabs, worms, eels, sea cucumbers and numerous small fish can be found. Dragging a scallop dredge over this destroys organisms by crushing, it stirs the sand which is resorted with finer particles settling after larger ones, the contours of the bed are flattened. Fishing trawl doors can penetrate up to 15 cm, beam trawls by 8 cm. Many areas of seabed are more varied than just sand (thankfully), but rocks can be moved even crushed (and animals under them crushed and exposed); gullies slowly filled, mounds levelled off and modern rock hopping fishing gear can work in these rocky areas. The habitats for many organisms will be disrupted or destroyed if the seabed is disturbed.

Lower-energy fishing techniques, such as lobster or crab pots, cause less bottom damage than heavy trolling gear but pots can have the problem of "ghost" fishing if lost. Scallops can even be collected by divers, as evidenced by Scotland's professional scallop divers; selective with minimal incidental damage.

In deeper water the same occurs, but out of sight, and even more out of mind. It wasn't till 1998, at a depth of 300 m off the north west tip of Scotland, some 185km out of Cape Wrath, that cold water coral reefs were discovered in the UK, now named the Darwin Mounds. This very slow-growing hard coral forms clumps up to 5 m high and 100 m long occurring in an area of about 100 square km. Similar areas have been discovered off Norway, Portugal, Ireland and the Azores. Like their tropical counterparts the reefs are complex and thought to form important nursery areas, even for commercially-valuable species. The main coral species in these cold waters, Lophelia pertusa, also occurs in warmer tropical waters such as the Indian Ocean, Pacific and Mediterranean but relatively little is know about these cold-water reefs. What has been discovered are deep scars and broken corals from bottom-trawling fishing vessels. Its now estimated that nearly half of these cold water coral areas have damage.

The UK environment secretary, Margaret Beckett, promised protection of these UK cold water corals at the 2002 WWF by designating them as a "Special Area of Conservation". This hasn't happened specificaly, but the good news is that in August 2003 the European Commission, working with this intention, introduced emergency fishing restrictions to protect the Darwin Mounds and stop the bottom trawling for 6 months. It's the first use of these EC emergency powers and proposals to permanently ban bottom trolling will be tabled under the EU Common Fisheries Policy. Norway has had such a ban on bottom trawling to protect cold-water reefs for some time now.

Further information can be found within the sites under marine at:
www.panda.org/ for the WWF
www.jncc.gov.uk/ The UK's Joint Nature Conservation Committee

Little protection for shallower sea beds in the UK is yet in place, but on an informal basis some areas such as Lyme Bay are at least considering the issue.

Sustainability
In August 2003 Iceland announced it would kill 38 of the small minke whales and has proceeded to do so. Norway also kills in excess of 500 minke whales each year. Japan has been killing a range of whales, dolphins and other cetaceans. Many countries are involved in "shark-finning". The UK and other European countries have depleted the cod, plaice, whiting, herring and haddock stocks. In Canada over-fishing of cod has resulted in a complete collapse of cod stocks. Abalone in California became endangered, and Atlantic swordfish, Atlantic bluefin tuna are over fished. The list can go on.

Fishing is one of the oldest endeavours known to man and some people, even as late as the 1950's, thought the seas could go on supplying us endlessly. Between 1950 and 1994 ocean catches increased by 400% by a doubling in the number of boats and increased efficiency. But by 1984 the actual tonnage caught had started to level off at 82 million metric tons per year and more people started listening to scientists who were warning that this couldn't go on. We were catching more than was sustainable. Species which had been plentiful were becoming scarce, species which earlier were considered "trash" became sought after (monkfish, sharks).

To move fishing into a sustainable endeavour is a huge political nightmare. Fishing is traditionally a hunter/gatherer activity, its an important or even main source of protein in some regions, and it's BIG money and jobs. About 200 million people are estimated to earn a living from some aspect of fishing, with about half of these in developing countries. Many different approaches from many levels are needed to keep fishing sustainable.

1st - The politics, the economics need to be recognised and dealt with
2nd - The biology, the ecology, now know need to be appreciated and used
3rd - Much more behavioural and ecological research is needed
4th - We are going to have to accept that some hunting needs replacement with farming
5th - Education, education, education is needed; of fisherman, of politicians of the general public
6th - Regulation and enforcement of of regulations

A modern factory ship can now haul in as much cod in an hour as a sixteenth century fishing boat would land in a year.

Control often hasn't worked. Just think of Europe's Common Fisheries Policy and individual countries squabbling over quotas! But controls are needed and they need to be developed in ways that allow them to work. They need to be supplemented with concerned individuals taking an active interest. I've seen illegal drift netting in Ireland when diving, I didn't do anything, maybe I should have!

1. Tourism can help
- whale watching can be as or more economically important than killing
- divers wanting to see sharks can generate more revenue than a dead shark
- divers wanting to see coral reefs without dynamite damage
- divers wanting to see fish and marine life, not just an empty seabed

2. Responsible consumer purchasing of fish Food, we all need it, but

3. The controls need to
- take an ecosystem approach, not just single species
- be tailored for the specific region, even specific boats
- treat bycatch as important
- adapt at least some of the precautionary attitude talked of by scientists

4. More baseline information is needed
- divers can help in marine surveys Eco Tours Table

5. Many activist organisations can use your support to see that controls are in place Environmental Organisations Table

6. Protected areas without any fishing do seem to work to replenish stocks


Bycatch
Most fishing methods are at least partly non-selective. What is caught and the resultant animals not wanted are referred to as the "Bycatch". Some of this may still have economic value and will be landed, but the majority is normally simply discarded, so we have economic and regulatory discards. This may include targeted fish which are too small or simply over quota limits, and it often includes other species. Recent estimates by the UN Food and Agriculture Organisation put the quantity of bycatch near 20 million metric tonnes, or 25% of all fish caught.

Particularly of interest to divers is "shark-finning", where the fins are cut off live sharks for sale in the Far East for shark fin soup and medicinal remedies, leaving the rest of the shark as bycatch which is thrown overboard to die. Marine mammals are another group of high profile casualties. Sea birds, sea turtles and many invertebrates all end up in the net or on the hook as bycatch.

Bycatch does make a difference - as its wasted.

1. It can be part of the food chain for other fish
2. It can be the juveniles which never get the chance to grow up
3. It can be endangered species (dolphins, sharks, sea birds)

1. A kilo of Shrimp caught in trawl nets can have up to 10 kilo of bycatch. This has lead the USA to ban the import of shrimp caught in some countries, particularly those which don't use methods to reduce turtle kills. Other shrimping methods, such as live traps, reduce bycatch to small numbers.
   
2. Long-lining, where many miles of line are put out using automated machines which bate the hooks along its length as it's deployed can have high bycatch. They catch birds, sharks, fish, seals and other fish going after both the bait and the caught fish. Some management techniques can reduce the bycatch, such as fishing only at night when birds are not feeding, staining the bait to discourage birds, setting the lines below the surface again to protect birds. Correct hook sizes can limit the "wrong" size catch.
   
3. Beam-trawling in the North Sea is estimated to have about 30% bycatch, mainly of unwanted fish. Otter trawlers also have a high rate of bycatch.

• what is the habitat
• what animals and plants exist in a location
• what are the numbers, i.e. density of different species
• what seasonal changes occur
• and what changes occur over time (years)