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In some countries attached algae belong to the coastal landowner (e.g., France).

Where concessions are given, e.g., in South Africa, New Zealand, the concept is that the enterprise works without competition, and the State benefits financially through the concession fee. Formerly, in New Zealand, the system worked as a monopoly. The buyer introduced his own system to protect the resource: he lowered the price until it was not feasible to collect other than the rich resources. The system had to be abandoned.

Apart from Chile, the only country in which concessions are known to be given to the fishermen is the People's Republic of China. Here a concession consists of a certain part of the coastline (as the natural substrates are unsuitable) and is given to a cooperative which practises mariculture in the area. The “marine farmers” have not only a fixed territory, but also fixed production quotas are set which have to be sold to the local administration at a fixed price. Additional taxes are imposed upon marine farmers who fail to join a cooperative.

In the Philippines, the concession of a certain area to a certain company includes wild crops as well as the right to cultivate.

In Japan, there is a complex and diversified system of concessions and fees, even for the right to cultivate Porphyra conchospores in tanks.


In Canada, research on harvesting methods for Chondrus crispus showed that these were of great importance for the regrowth. A hand rake was invented which detached only the fully developed fronds without harming the smaller ones, which then developed very quickly. This decreased the regrowth period to less than half, and thus doubled the potential of a bed. The Canadian hand rake is not directly adaptable to the Chilean species at present harvested, but the principle is of essential importance.

The Canadian Sea Plant Harvesting Act (Statutes of Nova Scotia 1959 Chapter 9) refers to the brown algae Ascophyllum and Laminaria but not to the red algae Chondrus and Palmaria. It states the following:

  1. A cutting instrument must be used

  2. The holdfast must not be damaged intentionally

  3. At least 5 inches of upright shoot must remain above the holdfast after harvesting

  4. Not more than 95 yd2 in any area of 100 yd2 can be cut

  5. A licence to harvest is required and will cost not less than Can. $ 50 or more than Can. $ 500

  6. A royalty of Can. $ 0.10/wet ton harvested shall be paid

  7. If the royalty exceeds the licence fee, the latter shall be deductible for the total payment

  8. Each licencee shall keep a record of the quantity collected and shall report the quantities annually.

The first point, that cutting instruments must be used, may seem surprising to anybody familiar with Chilean conditions, where handcutting is allowed and cutting instruments in principle not. However, both regulations are aiming at the same objective: to promote vegetative regrowth. In Gracilaria, a cutting instrument takes more of the basal parts than hand-cutting. In Canadian rock-weed and kelp the basal parts are extremely strong and cannot be torn away from the holdfast by hand. With a strong pull, however, the holdfast may come loose from the substrate. A cutting instrument, on the other hand can be adjusted to cut 15 cm from the rock, which will ascertain fastest possible regrowth?

In Norway, a similar study on Ascophyllum nodosum, a rock-weed of about 1 m height, showed that if 15 cm were left above the holdfast, re-growth time was essentially shorter than by harvesting a greater length. If the whole holdfast was extracted, there was also a risk that other species would colonize the rock before new Ascophyllum specimens grew from the spores.

Another harvesting method of economic interest (although not included in the legislation) is the Chinese tip-cutting of Laminaria. As in Durvillea, old parts of the fronds deteriorate in quality and are torn away by wave action or covered by epiphytes. If at a certain time-interval as much as one third of the frond is cut off and harvested, its loss is avoided and the remaining plant is given more space, light and nutrients for final growth (Tseng, 1981).

With a Lessonia harvest of about 50 000 t, very large gains can be made by using the harvesting method which allows the fastest regrowth. Having seen the plant only and not the harvesting the author estimates that the easiest way to collect it would be to cut immediately over the holdfast, and possibly the biologically correct way would be to leave some of the meristeme. Such a study has been carried out by Santelices and co-workers and showed that, if the stipe was left with a small part of the meristeme, it did not grow but was covered by bacteria as it did not sway with wave motions in its natural way. Another study could be carried out to determine if tip-cutting is feasible and economical.


In France a certain date is given as the first to harvest Laminaria in order to give the kelp a chance to form spores before being harvested.

In India consideration is given to quantity and quality. The first and last dates for harvesting are indicated in the legislation. Data on Hypnea from the Kathiawar peninsula give useful biological and chemical background:

Reproduction monthOct.     
Biomass high only in Dec.Jan.Feb.  
Hypnean content high only in  (Jan.)Feb.Mar. 
Gel strength high only in    Mar.Apr.

It can thus be reasonbly concluded that in this case Hypnea should be collected only from mid-February to mid-March.

It is recommended that similar studies are made on Chile's commercial species.

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